Agriculture

18 pages, 4803 KiB

Open AccessArticle

Fermentation Optimization, Fungistatic Effects and Tomato Growth Promotion of Four Biocontrol Bacterial Strains

by Yao Zhang, Xingyuan Wang, Sibo Liang, Yuying Shi, Xiuling Chen, Jiayin Liu and Aoxue Wang

Agriculture 2021, 11(7), 686; https://doi.org/10.3390/agriculture11070686 - 20 Jul 2021

Cited by 6 | Viewed by 4119

Abstract

Tomato is a widely cultivated crop that is important for its nutritional value and genetic diversity. Tomato production is seriously challenged by pests and diseases, among which tomato gray mold and leaf mold are particularly serious. Biological control is one of the most [...] Read more.

Tomato is a widely cultivated crop that is important for its nutritional value and genetic diversity. Tomato production is seriously challenged by pests and diseases, among which tomato gray mold and leaf mold are particularly serious. Biological control is one of the most preferred methods for disease management in tomato production. At present, the fungi used to control tomato gray mold are mainly Trichoderma and yeast. Bacillus and actinomycetes are the most effective microorganisms for controlling tomato leaf mold. Tomato gray mold and leaf mold often occur at the same time during the production process, yet there are fewer strains for controlling both diseases at the same time. Biocontrol bacteria Pseudomonas azotoformans WXCDD51, Bacillus sp. WXCDD105, Bacillus subtilis BS and Bacillus amyloliquefaciens BS WY-1, which were isolated and screened in the previous stage, can prevent both tomato gray mold and leaf mold. Here, we optimized liquid fermentation for the four biocontrol bacterial strains together. We obtained the best fermentation medium formula and fermentation conditions for the four biocontrol bacteria. The broad-spectrum properties of the four biocontrol bacteria were tested, and, on this basis, compound strains were constructed. The control effect of single and compound strains on tomato gray mold and leaf mold was evaluated. Their potential effects on the growth of tomato seeds and seedlings were also studied. This research provides a foundation for the development and use of compound bacteria for growth promotion and disease management in tomato production. Full article

► Show Figures

Figure 1

Figure 1
Germination rate of tomato seeds under the treatment of single and compound combined bacterial solutions. Full article ">Figure 2
Growth-promoting effect of single and compound combination bacterial liquids on the growth of tomato seed radicles. Full article ">Figure 3
Effects of biocontrol bacteria with different concentrations and treatments on the growth of tomato seedlings. (a) Effects of WXCDD51 fermentation broth on the growth of tomato seedlings with different concentrations (1) and different treatments (2). (b) Effects of WXCDD105 fermentation broth on the growth of tomato seedlings with different concentrations (1) and different treatments (2). (c) Effects of Ba fermentation broth on the growth of tomato seedlings with different concentrations (1) and different treatments (2). (d) Effects of Bs wy-1 fermentation broth on the growth of tomato seedlings with different concentrations (1) and different treatments (2). Full article ">Figure 4
(a) Effects of combination S-1 fermentation broth on the growth of tomato seedlings with different concentrations (1) and different treatments (2). (b) Effects of combination S-2 fermentation broth on the growth of tomato seedlings with different concentrations (1) and different treatments (2). (c) Comparison of effects of single and mixed fermentation broths on the growth of tomato seedlings. Full article ">Figure 5
Effects of single and compound strains on the in vitro fruits of tomato gray mold (a) and leaf mold (b). Full article ">Figure 6
Therapeutic effects of single and complex strains on tomato seedlings infected with gray mold. Full article ">Figure 7
Therapeutic effects of single and complex strains on tomato seedlings infected with leaf mold. Full article ">Figure 8
(a,b) Detection of secretory substances in strains WXCDD51 and WXCDD105. (c) Antibacterial activity of antibacterial crude protein. (d) Determination of antibacterial activity of lipopeptide antibiotics. Full article ">

15 pages, 2628 KiB

Open AccessArticle

Coronatine Modulated the Generation of Reactive Oxygen Species for Regulating the Water Loss Rate in the Detaching Maize Seedlings

by Haiyue Yu, Yubin Wang, Jiapeng Xing, Yushi Zhang, Liusheng Duan, Mingcai Zhang and Zhaohu Li

Agriculture 2021, 11(7), 685; https://doi.org/10.3390/agriculture11070685 - 20 Jul 2021

Cited by 8 | Viewed by 2782

Abstract

Coronatine (COR), a structural and functional mimic of jasmonates, is involved in a wide array of effects on plant development and defense response. The present study aims to investigate the role of COR, in counteracting drought stress by modulating reactive oxygen species (ROS) [...] Read more.

Coronatine (COR), a structural and functional mimic of jasmonates, is involved in a wide array of effects on plant development and defense response. The present study aims to investigate the role of COR, in counteracting drought stress by modulating reactive oxygen species (ROS) homeostasis, water balance, and antioxidant regulation in detached maize plants. Our results showed that COR can markedly decrease the water loss rate, but the antioxidants diphenyleneiodonium chloride (DPI) and dimethylthiourea (DMTU) eliminate the effect of water loss induced by COR. Using the dye 2′,7′-dichlorofluorescein diacetate (H2DCF-DA) loaded in the maize epidermis guard cells, it is observed that COR could increase ROS production, and then antioxidants DPI and DMTU decreased ROS production induced by COR. In addition, the expression of ZmRBOHs genes, which were associated with ROS generation was increased by COR in levels and ZmRBOHC was highly expressed in the epidermis guard cells. Moreover, COR-treated plants increased H₂O₂ and O₂⁻· accumulation, antioxidant enzyme activities in control plants, while COR relieved the ROS accumulation and antioxidant enzyme activities under PEG treatment. These results indicated that COR could improve maize performance under drought stress by modulating ROS homeostasis to maintain water loss rate and antioxidant enzyme activities. Full article

(This article belongs to the Special Issue Applications of Plant Growth Regulators and Hormones on Crop Resistance)

► Show Figures

Figure 1

Figure 1
Water loss rates of detached maize plants treated with gradient concentration of COR under PEG treatment. Plants were pre-treated with 0, 0.1, 0.01, 0.001, 0.0001 μM COR for 12 h, then water loss of isolated detached plants was monitored every 1 h over 8 h with 10% PEG treatment. Values are the mean ± SD (n = 8), asterisks indicate significant differences (p < 0.05) between 0 and 0.001 μM using Student’s t-test. Full article ">Figure 2
H2O2 and O2−· accumulation in leaves of maize plants after treatments with COR in well-watered and drought plants. (A) Histochemical detection of H2O2 and (B) O2−· with nitroblue tetrazolium (NBT) in maize leaves. The second leaves were homogenized, and (C) H2O2 content and (D) O2−· were assayed by spectrophotometry. CK and COR indicated the well-watered plants and well-watered plants treated with COR, respectively. PEG and PEG+COR indicate the water-stressed plants and water-stressed plants in presence of COR, respectively. Values are the mean ± SD (n =3), and different letters indicate significant differences (p < 0.05) among the treatments. Bars = 2 cm. Full article ">Figure 3
Activities of SOD (A), POD (B), CAT (C) in leaves of maize seedlings under 10% PEG treatment. CK and COR indicated the well-watered plants and well-watered plants treated with COR, respectively. PEG and PEG+COR indicate the water-stressed plants and water-stressed plants in presence of COR, respectively. Values are the mean ± SD (n = 3), and different letters indicate significant differences (p < 0.05) among the treatments. Full article ">Figure 4
Expression analysis of ZmDREB2A (A), ZmcAPX (B), and ZmCAT1 (C) in leaves of COR-treated and control plants under well-watered conditions and PEG treatment. The gene expression levels of COR-treated and control plants are shown relative to the expression of control plants grown under well-watered conditions at the corresponding time. CK and COR indicated the well-watered plants and well-watered plants treated with COR, respectively. PEG and PEG+COR indicate the water-stressed plants and water-stressed plants in presence of COR, respectively. One hour CK-treatment as calibrator samples. Values are the mean ± SD (n = 3), and different letters indicate significant differences (p < 0.05) among the treatments. Full article ">Figure 5
Expression patterns of ZmRBOHA (A), ZmRBOHB (B), and ZmRBOHC (C) in maize leaves exposed to COR. Relative expression levels of ZmRBOHA (A), ZmRBOHB (B), ZmRBOHC (C) genes, analyzed by real-time quantitative PCR, are presented as values relative to CK at 0 h, defined as 1, after normalization to β-tubulin transcript levels. Values are means ± standard error (n = 3), and different letters indicate significant differences (p < 0.05) among the treatments. Full article ">Figure 6
Water loss rate in antioxidants-treated detached maize plants. (A) Water loss rate of the pre-treated maize plants with distilled water and COR, subsequently exposed to dimethylthiourea (DMTU) and (B) diphenyleneiodonium chloride (DPI) for 8 h. Then subjected to 10% (w/v) polyethylene glycol (PEG 6000) solution. WS and COR indicated the distilled water-treated and COR-treated plants under PEG treatment conditions, respectively. DMTU/DPI and DMTU+COR/DPI+COR indicate the DMTU/DPI-treated and DMTU+COR/DPI+COR-treated plants under PEG treatment, respectively. The experiments were repeated three times with similar results. Each data point represents mean ± SE (n = 6), asterisks indicate significant differences (p < 0.05) between COR and DMTU/DPI treatment using Student’s t-test. Full article ">Figure 7
Effect of COR on the stomatal aperture in maize leaves treated with DMTU (A) and DPI (B). The experiments were repeated three times with similar results. Values are means ± standard error (n = 10), and different letters indicate significant differences (p < 0.05) among the treatments. Full article ">Figure 8
ROS production induced by COR in maize leaves and protoplasts. Effect of COR-induced ROS production in maize epidermal cells (A) and protoplasts (C) with DMTU and DPI. Values are means ± standard error, and different letters indicate significant differences (p < 0.05) among the treatments. (B) Dynamic accumulation of COR-induced ROS production in maize protoplasts. Data was collected every 2 min from 0 to 14 min. Values are the mean ± SD, asterisks indicate significant differences (p < 0.05) between CK and COR treatment using student’s t-test. Full article ">

17 pages, 4228 KiB

Open AccessEditor’s ChoiceArticle

Urease Inhibitors Effects on the Nitrogen Use Efficiency in a Maize–Wheat Rotation with or without Water Deficit

by Raúl Allende-Montalbán, Diana Martín-Lammerding, María del Mar Delgado, Miguel A. Porcel and José L. Gabriel

Agriculture 2021, 11(7), 684; https://doi.org/10.3390/agriculture11070684 - 20 Jul 2021

Cited by 18 | Viewed by 5252

Abstract

The use of urease inhibitors in irrigated systems decreases both soil ammonium (NH₄⁺) and nitrate (NO₃⁻) availability, and, thus, could be an easy tool to reduce N loss due to ammonia volatilization and NO₃⁻ leaching. [...] Read more.

The use of urease inhibitors in irrigated systems decreases both soil ammonium (NH₄⁺) and nitrate (NO₃⁻) availability, and, thus, could be an easy tool to reduce N loss due to ammonia volatilization and NO₃⁻ leaching. The main goal of this experiment was to assess the effect of urease inhibitors on N use efficiency, N losses, and their economic impact in a maize-wheat field experiment. In this study, 10 treatments were compared, combining the urea fertilizer with or without urease inhibitor, applied in one or two dressings, and under optimal or sub-optimal irrigation. A single application of urease inhibitor (IN_1d), coupled with the conventional urea, helped to reduce the nitrate leaching risk both during the maize period (even when compared to the two dressing treatment) and after harvest. In addition, this improvement was achieved together with an increase in economic benefit, even when compared with the application of the same amount of regular urea split into two dressings. Under low water availability systems, the benefits of applying urease inhibitors increased with respect to the application of regular urea, making this technique a very promising strategy for adaptation to climate change in arid and semiarid regions. Full article

(This article belongs to the Special Issue Effects of Fertilizer and Irrigation on Crop Production)

► Show Figures

Figure 1

21 pages, 10409 KiB

Open AccessArticle

Microbiological Effectivity Evaluation of New Poultry Farming Organic Waste Recycling

by Edit Gorliczay, Imre Boczonádi, Nikolett Éva Kiss, Florence Alexandra Tóth, Sándor Attila Pabar, Borbála Biró, László Renátó Kovács and János Tamás

Agriculture 2021, 11(7), 683; https://doi.org/10.3390/agriculture11070683 - 19 Jul 2021

Cited by 9 | Viewed by 4666

Abstract

Due to the intensification of the poultry sector, poultry manure is being produced in increasing quantities, and its on-site management is becoming a critical problem. Animal health problems can be solved by stricter the veterinary and environmental standards. The off-site coupled industrial chicken [...] Read more.

Due to the intensification of the poultry sector, poultry manure is being produced in increasing quantities, and its on-site management is becoming a critical problem. Animal health problems can be solved by stricter the veterinary and environmental standards. The off-site coupled industrial chicken manure recycling technology (Hosoya compost tea) fundamentally affects the agricultural value of new organic-based products. Due to the limited information available on manure recycling technology-related microbiological changes, this was examined in this study. A pot experiment with a pepper test plant was set up, using two different soils (Arenosol, slightly humous Arenosol) and two different doses (irrigation once a week with 40 mL of compost tea: dose 1, D1; irrigation twice a week with 40 mL of compost tea: dose 2, D2) of compost tea. Compost tea raw materials, compost tea, and compost tea treated soils were tested. The products (granulated manure, compost tea) and their effects were characterized by the following parameters: aerobic bacterial count (log CFU/g), fluorescein diacetate activity (3′,6′-diacetylfluorescein, FDA, µg Fl/g soil), glucosidase enzyme activity (GlA; PNP/µmol/g), and identification of microorganisms in compost tea with matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Furthermore, we aimed to investigate how the microbiological indicators tested, and the effect of compost tea on the tested plant, could be interpreted. Based on our results, the microbiological characteristics of the treated soils showed an increase in enzyme activity, in the case of FDA an increase +0.26 μg Fl/g soil at D1, while the GlA increased +1.28 PNP/µmol/g with slightly humous Arenosol soil and increased +2.44 PNP/µmol/g at D1; and the aerobic bacterial count increased +0.15 log CFU/g at D2, +0.35 log CFU/g with slightly humous Arenosol and +0.85 log CFU/g at W8. MALDI-TOF MS results showed that the dominant bacterial genera analyzed were Bacillus sp., Lysinibacillus sp., and Pseudomonas sp. Overall, the microbial inducers we investigated could be a good alternative for evaluating the effects of compost solutions in soil–plant systems. In both soil types, the total chlorophyll content of compost tea-treated pepper (Capsicum annuum L.) had increased as a result of compost tea. D1 is recommended for Arenosol and, D2 for slightly humous Arenosol soil. Full article

(This article belongs to the Special Issue Poultry: Breeding, Health, Nutrition, and Management)

► Show Figures

Figure 1

21 pages, 7071 KiB

Open AccessArticle

High Accuracy Pre-Harvest Sugarcane Yield Forecasting Model Utilizing Drone Image Analysis, Data Mining, and Reverse Design Method

by Bhoomin Tanut, Rattapoom Waranusast and Panomkhawn Riyamongkol

Agriculture 2021, 11(7), 682; https://doi.org/10.3390/agriculture11070682 - 19 Jul 2021

Cited by 13 | Viewed by 4351

Abstract

This article presents a new model for forecasting the sugarcane yield that substantially reduces current rates of assessment errors, providing a more reliable pre-harvest assessment tool for sugarcane production. This model, called the Wondercane model, integrates various environmental data obtained from sugar mill [...] Read more.

This article presents a new model for forecasting the sugarcane yield that substantially reduces current rates of assessment errors, providing a more reliable pre-harvest assessment tool for sugarcane production. This model, called the Wondercane model, integrates various environmental data obtained from sugar mill surveys and government agencies with the analysis of aerial images of sugarcane fields obtained with drones. The drone images enable the calculation of the proportion of unusable sugarcane (the defect rate) in the field. Defective cane can result from adverse weather or other cultivation issues. The Wondercane model is developed on the principle of determining the yield not through data in regression form but rather through data in classification form. The Reverse Design method and the Similarity Relationship method are applied for feature extraction of the input factors and the target outputs. The model utilizes data mining to recognize and classify the dataset from the sugarcane field. Results show that the optimal performance of the model is achieved when: (1) the number of Input Factors is five, (2) the number of Target Outputs is 32, and (3) the Random Forest algorithm is used. The model recognized the 2019 training data with an accuracy of 98.21%, and then it correctly forecast the yield of the 2019 test data with an accuracy of 89.58% (10.42% error) when compared to the actual yield. The Wondercane model correctly forecast the harvest yield of a 2020 dataset with an accuracy of 98.69% (1.31% error). The Wondercane model is therefore an accurate and robust tool that can substantially reduce the issue of sugarcane yield estimate errors and provide the sugar industry with improved pre-harvest assessment of sugarcane yield. Full article

(This article belongs to the Special Issue Internet of Things (IoT) for Precision Agriculture Practices)

► Show Figures

Figure 1

14 pages, 3309 KiB

Open AccessCommunication

Factors Affecting Tolerance to Low Night Temperature Differ by Fruit Types in Tomato

by Eun-Young Yang, Sherzod Nigmatullayevich Rajametov, Myeong-Cheoul Cho, Hyo-Bong Jeong and Won-Byoung Chae

Agriculture 2021, 11(7), 681; https://doi.org/10.3390/agriculture11070681 - 19 Jul 2021

Cited by 6 | Viewed by 3476

Abstract

Tolerance to low night temperature (LNT) can be a practical and economical target in tomato breeding programs for energy saving in greenhouses. This study was conducted to investigate the physiological and biochemical responses to LNT using four tomato accessions with cherry or large [...] Read more.

Tolerance to low night temperature (LNT) can be a practical and economical target in tomato breeding programs for energy saving in greenhouses. This study was conducted to investigate the physiological and biochemical responses to LNT using four tomato accessions with cherry or large fruit types having LNT tolerance or sensitivity. The accessions were grown in two polyethylene film greenhouses with night temperature set-points of 10 and 15 °C for heating. LNT significantly reduced the plant height, and photosynthetic parameters were also lower in 10 than 15 °C among all accessions. Photosynthetic rate in 10 °C during the early growth period was reduced more in LNT-tolerant than -sensitive accessions. The numbers of flowers in 10 °C were significantly reduced in cherry but not in large fruit types. Fruit set in 10 °C significantly decreased in LNT-sensitive accessions of both fruit types, which was due to abnormal flower morphology. Proline accumulation patterns between 10 and 15 °C significantly differed between cherry and large fruit types as well as between LNT-tolerant and -sensitive accessions. Chlorophyll content at later growth stages in 10 °C was significantly higher in LNT-tolerant than -sensitive accessions in both fruit types. These results suggest that different tomato fruit types may have different mechanisms for LNT tolerance, possibly due to different proline accumulation patterns between cherry and large fruit types. Full article

► Show Figures

Figure 1

14 pages, 714 KiB

Open AccessArticle

Phenotypic Characterisation for Growth and Nut Characteristics Revealed the Extent of Genetic Diversity in Wild Macadamia Germplasm

by Thuy T. P. Mai, Craig M. Hardner, Mobashwer M. Alam, Robert J. Henry and Bruce L. Topp

Agriculture 2021, 11(7), 680; https://doi.org/10.3390/agriculture11070680 - 19 Jul 2021

Cited by 11 | Viewed by 3240

Abstract

Macadamia is a recently domesticated Australian native nut crop, and a large proportion of its wild germplasm is unexploited. Aiming to explore the existing diversity, 247 wild accessions from four species and inter-specific hybrids were phenotyped. A wide range of variation was found [...] Read more.

Macadamia is a recently domesticated Australian native nut crop, and a large proportion of its wild germplasm is unexploited. Aiming to explore the existing diversity, 247 wild accessions from four species and inter-specific hybrids were phenotyped. A wide range of variation was found in growth and nut traits. Broad-sense heritability of traits were moderate (0.43–0.64), which suggested that both genetic and environmental factors are equally important for the variability of the traits. Correlations among the growth traits were significantly positive (0.49–0.76). There were significant positive correlations among the nut traits except for kernel recovery. The association between kernel recovery and shell thickness was highly significant and negative. Principal component analysis of the traits separated representative species groups. Accessions from Macadamia integrifolia Maiden and Betche, M. tetraphylla L.A.S. Johnson, and admixtures were clustered into one group and those of M. ternifolia F. Muell were separated into another group. In both M. integrifolia and M. tetraphylla groups, variation within site was greater than across sites, which suggested that the conservation strategies should concentrate on increased sampling within sites to capture wide genetic diversity. This study provides a background on the utilisation of wild germplasm as a genetic resource to be used in breeding programs and the direction for gene pool conservation. Full article

(This article belongs to the Special Issue Development and Cultivar Improvement of Nut Crops)

► Show Figures

Figure 1

21 pages, 9138 KiB

Open AccessArticle

Design and Experiment of the Automatic Laying System for Rice Seedling Tray

by Qiaojun Zhou, Xudong Xia, Jian Wang, Yun Zhou and Jianneng Chen

Agriculture 2021, 11(7), 679; https://doi.org/10.3390/agriculture11070679 - 19 Jul 2021

Cited by 1 | Viewed by 3626

Abstract

In the process of raising rice seedlings, it is necessary to manually place the seedling trays one by one in the seedling field, which is labor intensive and low in efficiency. In order to solve this problem, according to the actual conditions of [...] Read more.

In the process of raising rice seedlings, it is necessary to manually place the seedling trays one by one in the seedling field, which is labor intensive and low in efficiency. In order to solve this problem, according to the actual conditions of the rice seedling field, this paper designs and develops an automatic rice tray laying system, which consists of a gantry truss moving unit, a tray laying trolley unit, a tray laying mechanism unit and a sensor control unit. Through the movement and timing coordination of the cams in the laying mechanism unit, four actions of holding, clamping, laying and restoring are designed to realize the orderly and automatic laying of the stacked seedling trays one by one. In order to meet the agronomic requirements of the horizontal and vertical spacing of seeding trays, especially the efficiency of rice tray laying, the control strategies of the key parts of the system were simulated, selected and optimized. For the longitudinal movement of the gantry truss, the cross-coupling control strategy is adopted to realize the detection and compensation correction of the synchronous position error of the two driving motors. As for the drive motor of the laying trolley and the laying mechanism, the optimized master-slave follow-up control method is adopted to improve the efficiency and accuracy. The results of simulation and field experiment show that when the tray trolley moves on the gantry truss at the speed of 7.5 cm/s, the gantry truss moves at the speed of 35 cm/s in the longitudinal direction, and when the height of the tray laying mechanism is 100 mm from the ground and the motor speed is 375 rpm, the horizontal spacing of the tray can be maintained at 25 ± 5 mm and the vertical spacing at 15 ± 5 mm. The efficiency of tray laying can be increased by 35.7%, up to 380 trays/h, meeting the technical requirements of mechanized field tray laying. Full article

(This article belongs to the Section Agricultural Technology)

► Show Figures

Figure 1

14 pages, 1047 KiB

Open AccessArticle

Rhizobium Inoculation and Chemical Fertilisation Improve Faba Bean Yield and Yield Components in Northwestern Ethiopia

by Getenesh Genetu, Markku Yli-Halla, Mekonnen Asrat and Mihiret Alemayehu

Agriculture 2021, 11(7), 678; https://doi.org/10.3390/agriculture11070678 - 19 Jul 2021

Cited by 7 | Viewed by 3479

Abstract

The productivity of the faba bean has declined in Ethiopia, owing to poor management practices, such as blanket fertilisation. In 2018, a field experiment was conducted in a Nitisol soil during the main cropping season in Northwestern Ethiopia, to determine the amount of [...] Read more.

The productivity of the faba bean has declined in Ethiopia, owing to poor management practices, such as blanket fertilisation. In 2018, a field experiment was conducted in a Nitisol soil during the main cropping season in Northwestern Ethiopia, to determine the amount of chemical fertiliser and Rhizobium inoculant to be used for the optimum yield within economic feasibility. The experiment consisted of a factorial combination of five rates of blended NPSZnB fertiliser (0, 60, 121, 180 and 240 kg ha⁻¹) and three rates of inoculant (0, 500 and 750 g ha⁻¹). Sole chemical fertilisation, as well as inoculation, individually produced a seed yield of 2.3–2.5 t ha⁻¹, about 1.0–1.2 t ha⁻¹ more than the control. However, the maximum seed yield (3.3 t ha⁻¹) was recorded from the combined application of both the chemical fertiliser and the inoculant. The seed yield correlated closely with the number of active nodules (R² = 0.78 **), suggesting a substantial contribution of symbiotic N₂ fixation. Inoculation increased the N content of the seed yield by at least 30 kg ha⁻¹. Chemical fertilisation, containing at least 44 kg ha⁻¹ of mineral N does not appear to have an adverse effect on N₂ fixation. The combined use of 180 kg ha⁻¹ blended fertiliser with 750 g ha⁻¹ inoculant, producing a maximum net profit of 72,918 birr ha⁻¹ (EUR 2232), is recommended for the study area. This study emphasises that (1) inoculation alone can produce as much seed as the maximum rate of chemical fertilisation, but (2) the maximum yield was produced with a combined use of inoculant and chemical fertiliser, by promoting the vigour of the nodules and N₂ fixation. Full article

(This article belongs to the Section Crop Production)

► Show Figures

Figure 1

20 pages, 2268 KiB

Open AccessArticle

An Analysis of Mushroom Consumption in Hungary in the International Context

by Bernadett Bringye, Maria Fekete-Farkas and Szergej Vinogradov

Agriculture 2021, 11(7), 677; https://doi.org/10.3390/agriculture11070677 - 18 Jul 2021

Cited by 10 | Viewed by 7876

Abstract

It is hardly an exaggeration to state that producing and consuming mushrooms may provide an answer to several of the challenges facing mankind. This research is related to the UN sustainable development goals relative to different issues. First of all, mushroom production uses [...] Read more.

It is hardly an exaggeration to state that producing and consuming mushrooms may provide an answer to several of the challenges facing mankind. This research is related to the UN sustainable development goals relative to different issues. First of all, mushroom production uses agricultural and industrial byproducts as inputs and being labor intensive contributes to the job and income creation for undereducated people in less developed areas. In addition, as mushrooms have high protein content and they are a suitable alternative for meat for populations with a diet lacking in variety; at the same time, they also have the potential for food connoisseurs and consumers who make conscious and educated choices to improve their diet by using healthful and environmentally friendly methods. The nutritional value of mushrooms means that consumption could be an important supplementary therapy for several illnesses. The key issue of sector development is the increasing demand. In order to address this, investigation and research related to consumer behavior is needed. The aim of this research was to explore the dimensions of Hungarian mushroom consumer behavior and to segment Hungarian consumers. An online questionnaire survey was conducted between December 2019 and February 2020 and the final sample of 1768 respondents was considered for the purposes of analysis. Exploratory factor analysis was used to identify groups of correlating variables describing mushroom consumption. The authors identified four dimensions of Hungarian mushroom consumer behavior: (1) medicinal and functional properties, (2) consumption for enjoyment, (3) supplementary food source, and (4) negative assessment of the product range. Using cluster analysis, three consumer groups were identified: (1) health-conscious consumers, (2) indifferent consumers, and (3) average consumers. The research results indicated that consumers’ sociodemographic characteristics (age, educational level, marital status, and place of residence) have a significant impact on mushroom consumption behavior. The results of this paper can have implications for policy makers and business management in diversifying their production and selecting marketing tools. Full article

(This article belongs to the Special Issue Agricultural Food Marketing, Economics and Policies)

► Show Figures

Figure 1

Figure 1
Research framework for examining factors influencing consumer behavior towards mushrooms in Hungary. Full article ">Figure 2
Word cloud of word associations related to mushrooms (source: own research, N = 598). Full article ">Figure 3
Standardized solution for the model with four factors based on Confirmatory factor analysis (N = 884). Full article ">Figure 4
Characteristics of the clusters generated based on level of consciousness in consumption. Full article ">Figure 5
Age distribution within clusters generated based on the level of consciousness in mushroom consumption. Full article ">Figure 6
Distribution by educational level within clusters generated based on level of consciousness in mushroom consumption. Full article ">Figure 7
Distribution of family status within clusters generated based on level of consciousness in mushroom consumption. Full article ">Figure 8
Distribution by location within clusters generated based on level of consciousness in mushroom consumption. Full article ">

7 pages, 4674 KiB

Open AccessCommunication

A Facile and Modified Scheme for Synchronization and Isolation of Nematode Eggs

by Satish Kumar Rajasekharan, Chaitany Jayprakash Raorane and Jintae Lee

Agriculture 2021, 11(7), 676; https://doi.org/10.3390/agriculture11070676 - 18 Jul 2021

Cited by 5 | Viewed by 3109

Abstract

Nematodes are common pests that damage agricultural crop plants. Some of them are beneficial while others are parasitic and harmful to plants, animals and humans. Several in vitro studies have aimed to develop chemicals to kill parasitic nematodes, while others have been conducted [...] Read more.

Nematodes are common pests that damage agricultural crop plants. Some of them are beneficial while others are parasitic and harmful to plants, animals and humans. Several in vitro studies have aimed to develop chemicals to kill parasitic nematodes, while others have been conducted to use beneficial nematodes as biocontrol agents. However, the preparation of large quantities of nematode eggs in a laboratory setting is challenging. Traditional egg isolation protocols involve the use of sieves to filter eggs or the use of chemicals that can be harmful to nematodes while isolating the eggs. Our method utilizes 1.5 × 1.5 cm sized chunks of bacterial or fungal feed to lure nematodes. A subsequent gentle washing of the consumed chunk with distilled water provides a rapid and straightforward method of collecting eggs in 6-well polystyrene plates and removing unwanted nematodes. Approximately 4000 Bursaphelenchus xylophilus eggs from a fungal chunk and 2400 Caenorhabditis elegans eggs from a bacterial chunk were obtained when tested. This study shows a protocol for the isolation of eggs and synchronization of nematode stages that is relatively straightforward, rapid, eco-friendly, and efficient. The protocol also provides a chemical-free and a reliable, simple means of separating eggs from adults and induces the synchronization of nematodes based on the simple concept that gravid nematodes can be provoked to lay eggs by providing additional feed. Full article

(This article belongs to the Section Crop Protection, Diseases, Pests and Weeds)

► Show Figures

Figure 1

8 pages, 1477 KiB

Open AccessCommunication

Detecting Dairy Cow Behavior Using Vision Technology

by John McDonagh, Georgios Tzimiropoulos, Kimberley R. Slinger, Zoë J. Huggett, Peter M. Down and Matt J. Bell

Agriculture 2021, 11(7), 675; https://doi.org/10.3390/agriculture11070675 - 17 Jul 2021

Cited by 23 | Viewed by 4816

Abstract

The aim of this study was to investigate using existing image recognition techniques to predict the behavior of dairy cows. A total of 46 individual dairy cows were monitored continuously under 24 h video surveillance prior to calving. The video was annotated for [...] Read more.

The aim of this study was to investigate using existing image recognition techniques to predict the behavior of dairy cows. A total of 46 individual dairy cows were monitored continuously under 24 h video surveillance prior to calving. The video was annotated for the behaviors of standing, lying, walking, shuffling, eating, drinking and contractions for each cow from 10 h prior to calving. A total of 19,191 behavior records were obtained and a non-local neural network was trained and validated on video clips of each behavior. This study showed that the non-local network used correctly classified the seven behaviors 80% or more of the time in the validated dataset. In particular, the detection of birth contractions was correctly predicted 83% of the time, which in itself can be an early warning calving alert, as all cows start contractions several hours prior to giving birth. This approach to behavior recognition using video cameras can assist livestock management. Full article

(This article belongs to the Special Issue Enhancing Farm-Level Decision Making through Innovation)

► Show Figures

Figure 1

8 pages, 6358 KiB

Open AccessArticle

Identification and Quantification of Olive Oil Quality Parameters Using an Electronic Nose

by Nawaf Abu-Khalaf

Agriculture 2021, 11(7), 674; https://doi.org/10.3390/agriculture11070674 - 16 Jul 2021

Cited by 16 | Viewed by 3979

Abstract

An electronic nose (EN), which is a kind of chemical sensors, was employed to check olive oil quality parameters. Fifty samples of olive oil, covering the four quality categories extra virgin, virgin, ordinary virgin and lampante, were gathered from different Palestinian cities. The [...] Read more.

An electronic nose (EN), which is a kind of chemical sensors, was employed to check olive oil quality parameters. Fifty samples of olive oil, covering the four quality categories extra virgin, virgin, ordinary virgin and lampante, were gathered from different Palestinian cities. The samples were analysed chemically using routine tests and signals for each chemical were obtained using EN. Each signal acquisition represents the concentration of certain chemical constituents. Partial least squares (PLS) models were used to analyse both chemical and EN data. The results demonstrate that the EN was capable of modelling the acidity parameter with a good performance. The correlation coefficients of the PLS-1 model for acidity were 0.87 and 0.88 for calibration and validation sets, respectively. Furthermore, the values of the standard error of performance to standard deviation (RPD) for acidity were 2.61 and 2.68 for the calibration and the validation sets, respectively. It was found that two principal components (PCs) in the PLS-1 scores plot model explained 86% and 5% of EN and acidity variance, respectively. PLS-1 scores plot showed a high performance in classifying olive oil samples according to quality categories. The results demonstrated that EN can predict/model acidity with good precision. Additionally, EN was able to discriminate between diverse olive oil quality categories. Full article

(This article belongs to the Special Issue Applications of Sensor Technology to Agri-Food Systems)

► Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
The prototype electronic nose (EN) used in the measurements. It is composed of eight metal-oxide semiconductors (MOS) sensors. Full article ">Figure 2
Steps for samples measurements by the electronic nose (EN) after chemical tests had been carried out. Full article ">Figure 3
Responses the sensors for two samples according to the different groups of olive oil quality. Least significant differences (LSD; p < 0.05) test showed that there were five groups of sensors according to their signal’s significance: A, MQ-2 and MQ-5; B, MQ-3; C, MQ-4; D, MQ-6 and MQ-135; E, MQ-8; and F, MQ-138. Full article ">Figure 4
Acidity partial least squares-1 (PLS-1) models using electronic nose (EN) signals (X-matrix) and acidity (Y-matrix) using a test set validation. (A) Calibration set (35 samples) and (B) validation set (15 samples). E, extra virgin; V, virgin; OV, ordinary virgin; and L, lampante. Full article ">Figure 5
Scores plot of the partial least squares-1 (PLS-1) model between electronic nose (EN) (X-matrix) and acidity (Y-matrix) for all 50 samples of olive oil using full cross-validation. Two principal components (PCs) explained 86% and 5% of the variance of EN signals and acidity values, respectively. Full article ">

15 pages, 3828 KiB

Open AccessEditor’s ChoiceArticle

Nondestructive Testing Model of Tea Polyphenols Based on Hyperspectral Technology Combined with Chemometric Methods

by Xiong Luo, Lijia Xu, Peng Huang, Yuchao Wang, Jiang Liu, Yan Hu, Peng Wang and Zhiliang Kang

Agriculture 2021, 11(7), 673; https://doi.org/10.3390/agriculture11070673 - 16 Jul 2021

Cited by 22 | Viewed by 3704

Abstract

Nondestructive detection of tea’s internal quality is of great significance for the processing and storage of tea. In this study, hyperspectral imaging technology is adopted to quantitatively detect the content of tea polyphenols in Tibetan teas by analyzing the features of the tea [...] Read more.

Nondestructive detection of tea’s internal quality is of great significance for the processing and storage of tea. In this study, hyperspectral imaging technology is adopted to quantitatively detect the content of tea polyphenols in Tibetan teas by analyzing the features of the tea spectrum in the wavelength ranging from 420 to 1010 nm. The samples are divided with joint x-y distances (SPXY) and Kennard-Stone (KS) algorithms, while six algorithms are used to preprocess the spectral data. Six other algorithms, Random Forest (RF), Gradient Boosting (GB), Adaptive boost (AdaBoost), Categorical Boosting (CatBoost), LightGBM, and XGBoost, are used to carry out feature extractions. Then based on a stacking combination strategy, a new two-layer combination prediction model is constructed, which is used to compare with the four individual regressor prediction models: RF Regressor (RFR), CatBoost Regressor (CatBoostR), LightGBM Regressor (LightGBMR) and XGBoost Regressor (XGBoostR). The experimental results show that the newly-built Stacking model predicts more accurately than the individual regressor prediction models. The coefficients of determination

R_{c}^{2}

and

R_{p}^{2}

for the prediction of Tibetan tea polyphenols are 0.9709 and 0.9625, and the root mean square error RMSEC and RMSEP are 0.2766 and 0.3852 for the new model, respectively, which shows that the content of Tibetan tea polyphenols can be determined with precision. Full article

► Show Figures

Figure 1

Figure 1
Schematic diagram of the hyperspectral imaging system. Full article ">Figure 2
Prediction results of GBR model with different inputs. (a) Modeling results based on KS partition data set; (b) Modeling results based on SPXY partition data set. Full article ">Figure 3
Tibetan tea spectrum curve. (a) Raw data; (b) Data preprocessed by SG algorithm; (c) Enlarged view of the red frame in Figure (a); (d) Enlarged view of the red frame in Figure (b). Full article ">Figure 4
Prediction results of tea polyphenols after pretreatment of raw spectra by SG algorithm, and “%” indicates the percentage of tea polyphenols in the dry matter of the tea sample. Full article ">Figure 5
Feature bands selected by different algorithms. (a) GB; (b) AdaBoost; (c) RF; (d) CatBoost; (e) LightGBM and (f) XGBoost. Full article ">Figure 5 Cont.
Feature bands selected by different algorithms. (a) GB; (b) AdaBoost; (c) RF; (d) CatBoost; (e) LightGBM and (f) XGBoost. Full article ">Figure 6
Flow chart depicting the stacking regressor model used for tea polyphenols prediction. Full article ">Figure 7
Prediction results of tea polyphenols based on CatBoost + Stacking model, “%” indicates the percentage of tea polyphenols in the dry matter of tea sample. (a) The modeling results before replacing the samples. (b) The modeling results after replacing the samples. Full article ">

14 pages, 1150 KiB

Open AccessEditor’s ChoiceArticle

Impact of Packing Density on the Bacterial Community, Fermentation, and In Vitro Digestibility of Whole-Crop Barley Silage

by Lin Sun, Na Na, Xiaomei Li, Ziqin Li, Chao Wang, Xiaoguang Wu, Yanzi Xiao, Guomei Yin, Sibo Liu, Zhiping Liu, Yanlin Xue and Fuyu Yang

Agriculture 2021, 11(7), 672; https://doi.org/10.3390/agriculture11070672 - 15 Jul 2021

Cited by 22 | Viewed by 3601

Abstract

Packing density has a significant influence on the outcome of ensiling forage. In this study, we aim to investigate the effect of packing density on the ensiling properties, microbiome, and in vitro digestibility of barley silages. Barley was ensiled in polyethylene drum silos [...] Read more.

Packing density has a significant influence on the outcome of ensiling forage. In this study, we aim to investigate the effect of packing density on the ensiling properties, microbiome, and in vitro digestibility of barley silages. Barley was ensiled in polyethylene drum silos (30 L) with respective densities of 600, 650, 700, and 750 kg/m³ fresh matter (FM), and stored for 60 days. The bacterial communities, fermentation quality, and in vitro digestibility were analyzed. Fresh barley had a low count of lactic acid bacteria (LAB, 10⁴ cfu/g of FM), and Lactobacillus was nearly undetectable (<1%). Increasing the packing density decreased the pH and the content of ammonia nitrogen (NH₃-N), ethanol, neutral detergent fiber (NDF), and acid detergent fiber (ADF) of barley silage (p < 0.05), and increased in vitro digestibility of dry matter, NDF, ADF, and DM recovery (p < 0.05). A higher packing density decreased the abundances of Enterobacter (from 47.4% to 35.4%) and Clostridium (from 13.5% to 3.8%), and increased the abundance of Lactobacillus (from 1.8% to 17.0%). Thus, packing density positively correlated with Lactobacillus (p < 0.05) but negatively correlated with Enterobacter (p < 0.05). The pH and the content of ethanol were positively correlated with Enterobacter (p < 0.05) but negatively correlated with Lactobacillus (p < 0.05). In conclusion, the density of 750 kg/m³ FM resulted in the highest silage quality of the densities tested. Full article

(This article belongs to the Special Issue Forage Quality, Conservation and Evaluation in Ruminant Production Systems)

► Show Figures

Figure 1

12 pages, 3262 KiB

Open AccessArticle

Effect of Colour of Light on Rooting Cuttings and Subsequent Growth of Chrysanthemum (Chrysanthemum × grandiflorum Ramat./Kitam.)

by Anita Schroeter-Zakrzewska and Faisal Anggi Pradita

Agriculture 2021, 11(7), 671; https://doi.org/10.3390/agriculture11070671 - 15 Jul 2021

Cited by 10 | Viewed by 4032

Abstract

A closed system for plant production with artificial light is an innovative method of plant cultivation. The objective of this study was to investigate the effect of light colour on rooting cuttings and subsequent growth of chrysanthemum (Chrysanthemum × grandiflorum Ramat./Kitam.) During [...] Read more.

A closed system for plant production with artificial light is an innovative method of plant cultivation. The objective of this study was to investigate the effect of light colour on rooting cuttings and subsequent growth of chrysanthemum (Chrysanthemum × grandiflorum Ramat./Kitam.) During the experiments, the following conditions were maintained: photoperiod 16 h or 10 h, temperature 22 °C, relative humidity of 65–70%. LED lamps emitted the following light colours: white, blue, white + blue (50:50), and red + blue (75:25). For all light spectra, the photosynthetic photon flux density (PPFD) was 50 μmol m⁻² s⁻¹. The effectiveness of exposure to different light colours was measured with parameters: cutting weight (g), cutting length (cm), length of roots, and index of leaf greenness (SPAD). The measurements referred to plant features determining plant quality, i.e., the number of flower buds and flower head, the diameter of the flower head, height of plants, index of leaf greenness (SPAD), the number of leaves, and the fresh and dry weights of aboveground parts of plants. The rooting of cuttings and subsequent growth are integral processes in the cultivation of potted chrysanthemums. Both were differently affected by the colour of light from LED lamps. The exposure to red + blue light resulted in the highest leaf greenness index (SPAD) value and the shortest cuttings with the longest roots. White + blue light significantly influenced most of the growth parameters, except the height of the plants and the number of leaves. Full article

(This article belongs to the Special Issue Impact of Light on Horticultural Crops)

► Show Figures

Figure 1

23 pages, 795 KiB

Open AccessArticle

The Organisational Resilience (OR) of Rural Non-Profits (RNPOs) under Conditions of the COVID-19 Pandemic Global Uncertainty

by Grzegorz Tadeusz Paluszak, Joanna Alicja Wiśniewska-Paluszak, Joanna Schmidt and Jarosław Lira

Agriculture 2021, 11(7), 670; https://doi.org/10.3390/agriculture11070670 - 15 Jul 2021

Cited by 9 | Viewed by 4249

Abstract

The study investigated the organisational resilience (OR) levels of rural non-profit organisations (RNPOs) in the areas of activity or non-activity to adapt under the global uncertainty conditions of the COVID-19 pandemic. To this end, in April/May 2020, the managers of 35 RNPOs located [...] Read more.

The study investigated the organisational resilience (OR) levels of rural non-profit organisations (RNPOs) in the areas of activity or non-activity to adapt under the global uncertainty conditions of the COVID-19 pandemic. To this end, in April/May 2020, the managers of 35 RNPOs located in Poland were queried. The Spearman’s rank correlation coefficient (

ρ_{S}

), the coefficient of determination (

R^{2})

and a transformation coefficient (d) were primarily used to verify the hypotheses and interpret the relationships studied. The study revealed four OR descriptive levels—progressive (PR), sustainable (SR), regressive (RR), and downward (DR). The findings also show that the undertaken activities are related to the OR descriptive levels. RNPOs realised one of two adaptations: passive adaptation aimed at returning to the pre-pandemic original state with no changes may lead to a bounce backwards and an uncertain survival, whilst active adaptation leads to a transformation process between OR levels to move forward and thrive in adapting to post-pandemic changes. This study confirmed that building OR requires understanding the ways of transformations among OR levels to undertake activities in strategic areas, i.e., activity scope (AS), cooperation (CO), and finance (FI), to adapt and transform RNPOs’ in an environment of post-pandemic uncertainty. Full article

(This article belongs to the Special Issue Challenges of Contemporary Agriculture, Rural Areas and Agri-Food Supply Chain under Conditions of Uncertainty)

► Show Figures

Figure 1

22 pages, 2458 KiB

Open AccessArticle

Scheduling Regulated Deficit Irrigation with Leaf Water Potential of Cherry Tomato in Greenhouse and its Effect on Fruit Quality

by Leontina Lipan, Hanán Issa-Issa, Alfonso Moriana, Noemí Medina Zurita, Alejandro Galindo, María José Martín-Palomo, Luis Andreu, Ángel A. Carbonell-Barrachina, Francisca Hernández and Mireia Corell

Agriculture 2021, 11(7), 669; https://doi.org/10.3390/agriculture11070669 - 15 Jul 2021

Cited by 19 | Viewed by 3723

Abstract

The tomato cultivated surface is one of the most important surfaces in the world. This crop needs a sufficient and continuous supply of water during vegetative growth. Therefore, production may be at risk in warm and water-scarce areas. Therefore, the implementation of irrigation [...] Read more.

The tomato cultivated surface is one of the most important surfaces in the world. This crop needs a sufficient and continuous supply of water during vegetative growth. Therefore, production may be at risk in warm and water-scarce areas. Therefore, the implementation of irrigation alternatives such as regulated deficit irrigation (RDI) is of great importance to reduce the use of water and improve the production of the quality of tomatoes. The objective of this work was to evaluate the deficit irrigation scheduling using plant water status as a tool in deficit irrigation. Experimental design was a randomized design with four replications per treatment. Two irrigation treatments were applied: Control (125% of crop evapotranspiration (ETc)) and Regulated Deficit Irrigation (RDI). This latter treatment considered different threshold values of midday leaf water depending on crop phenological stage. No differences were observed in yield, with RDI treatment being more efficient in the use of irrigation water than the control. Besides, RDI tomatoes presented, in general, greater weight, size, Total soluble solids (TSS), sugars, antioxidant activity, lycopene, β-Carotene, and redder color with more intense tomatoes flavor. Finally, it might be said that RDI strategy helped to reduce 53% of irrigation water and to improve the nutritional, functional, and sensory quality of tomatoes. Full article

(This article belongs to the Special Issue Future of Irrigation in Agriculture)

► Show Figures

Figure 1

Figure 1
Climatic conditions in the greenhouse. (a): Maximum (brown) and minimum (yellow) temperature; (b): Evapotranspiration (ETo) (blue) and vapor pressure deficit (VPD) (grey). Full article ">Figure 2
Quadratic correlation between: Sugars (glucose and fructose) and total soluble solids (TSS). Four repetitions per treatment were used for the correlation. Full article ">Figure 3
Quadratic correlation between β-carotene and lycopene content. Four repetitions per treatment were used for the correlation. Full article ">Figure 4
Descriptive sensory analysis in cherry tomato samples * p < 0.05, ** p < 0.01 and *** p < 0.001. Full article ">Figure 5
(a) PCA and (b) cluster maps prepared using, (◆) Stress Integral, (●) color, (−) TSS, pH, titratable acidity, maturity index, organic acids, and sugars, (■) antioxidant activity, lycopene¸ β-Carotene and total polyphenol content, (Δ) sensory profile, and (◆) volatile compounds in cherry tomato samples. Full article ">Figure 6
Quadratic correlation between: (a) Total phenolic content (TPC) and stress integral (SI) and (b) Antioxidant activity content (FRAP). Four repetitions per treatment were used for the correlation. Full article ">

12 pages, 1068 KiB

Open AccessArticle

Evaluation of Potato Varieties Grown in Hydroponics for Phosphorus Use Efficiency

by Wei-Chieh Lee, Lincoln Zotarelli, Diane L. Rowland and Guodong Liu

Agriculture 2021, 11(7), 668; https://doi.org/10.3390/agriculture11070668 - 15 Jul 2021

Cited by 3 | Viewed by 2738

Abstract

Global phosphate mineral resources are nonrenewable and are inevitably depleting. Exploiting elite varieties has become imperative for the efficient use of phosphorus (P) for sustainable crop production. Three potato varieties were hydroponically evaluated for P mobilization, uptake, and utilization efficiencies at different P [...] Read more.

Global phosphate mineral resources are nonrenewable and are inevitably depleting. Exploiting elite varieties has become imperative for the efficient use of phosphorus (P) for sustainable crop production. Three potato varieties were hydroponically evaluated for P mobilization, uptake, and utilization efficiencies at different P levels and sources during 28 d seedling growth. ‘Harley Blackwell’, ‘La Chipper’, and ‘Red LaSoda’ were selected from a previous study and grown in modified Hoagland solution, with different P concentrations of soluble high P as NaH₂PO₄ (10 mg L⁻¹ P), soluble low P (1 mg L⁻¹ P), and 286 mg L⁻¹ sparingly soluble P as tri-calcium phosphate [TCP, Ca₃(PO₄)₂] with 2286 mg L⁻¹ CaSO₄. ‘Harley Blackwell’ and ‘La Chipper’ had significantly greater biomass than ‘Red LaSoda’ in the low P or TCP treatments. In low-P stress, P utilization efficiency was significantly greater for ‘Harley Blackwell’ than that of the other two varieties. ‘Red LaSoda’ was more efficient in P mobilization from TCP as compared to the other two cultivars. The holistic score analysis indicated that ‘Harley Blackwell’ was the most P-efficient while ‘Red LaSoda’ was the least P-efficient. The results of this study show that the TCP solution was successful for screening P-efficient potato varieties. Full article

► Show Figures

Figure 1

Figure 1
Total biomass of potato seedlings grown in modified Hoagland solution with different P bioavailabilities for 28 days. Histograms with different letters in the same treatment are different at p < 0.05. Control: 10 mg L−1 P water soluble P as NaH2PO4; Low P: 1 mg L−1 P water soluble P as NaH2PO4; and 286 mg L−1 sparsely soluble P as TCP, tri-calcium phosphate, Ca3(PO4)2 with 2286 mg L−1 laboratory grade. HB: ‘Harley Blackwell’; LC: ‘La Chipper’; RL: ‘Red LaSoda’. The bars are the values of LSD0.05, 2 for the plant biomass of the control, low P and TCP, respectively. Full article ">Figure 2
Phosphorus uptake in 28-days old potato seedlings grown in modified Hoagland solution with different P bioavailabilities. Histograms with different letters in the same treatment are different at p < 0.05. Control: 10 mg L−1 P as water soluble P, NaH2PO4; Low P: 1 mg L−1 P as water soluble P, NaH2PO4; and 286 mg L−1 TCP, tri-calcium phosphate, Ca3(PO4)2 as sparsely soluble P with 2286 mg L−1 laboratory grade Ca3(PO4)2. HB: ‘Harley Blackwell’; LC: ‘La Chipper’; RL: ‘Red LaSoda’. The bars are the values of LSD0.05, 2 for the plant biomass of the control, low P and TCP, respectively. Full article ">Figure 3
Phosphorus utilization efficiency of 28-days old potato seedlings grown in modified Hoagland solution with different P bioavailabilities. Histograms with different letters in the same treatment are different at p < 0.05. Control: 10 mg L−1 P as water soluble P, NaH2PO4; Low P: 1 mg L−1 P as water soluble P, NaH2PO4; and 286 mg L−1 TCP, tri-calcium phosphate, Ca3(PO4)2 as sparsely soluble P with 2286 mg L−1 laboratory grade Ca3(PO4)2. HB: ‘Harley Blackwell’; LC: ‘La Chipper’; RL: ‘Red LaSoda’. The bars are the values of LSD0.05,2 for the plant biomass of the control, low P and TCP, respectively. Full article ">Figure 4
Root–shoot ratio of potato seedlings grown in modified Hoagland solution with different P bioavailabilities for 28 days. Histograms with different letters in the same treatment are different at p < 0.05. Control: 10 mg L−1 P as water soluble P, NaH2PO4; Low P: 1 mg L−1 P as water soluble P, NaH2PO4; and 286 mg L−1 TCP, tri-calcium phosphate, Ca3(PO4)2 as sparsely soluble P and 2286 mg L−1 laboratory grade Ca3(PO4)2. HB: ‘Harley Blackwell’; LC: ‘La Chipper’; RL: ‘Red LaSoda’. The bars are the values of LSD0.05, 2 for the plant biomass of the control, low P and TCP, respectively. Full article ">Figure 5
Holistic scores for the low-P tolerance of the potato varieties based on the measurements of P uptake, P utilization efficiency, and biomass produced by the individual varieties grown in hydroponics for 28 days. Low P: 1 mg L−1 P as water soluble P, NaH2PO4; and 286 mg L−1 TCP, tri-calcium phosphate, Ca3(PO4)2 as sparsely soluble P with 2286 mg L−1 laboratory grade Ca3(PO4)2. HB: ‘Harley Blackwell’; LC: ‘La Chipper’; RL: ‘Red LaSoda’. The bars are the values of LSD0.05, 2 for the plant biomass of the control, low P and TCP, respectively. Full article ">

15 pages, 2079 KiB

Open AccessArticle

Multi-Allelic Haplotype-Based Association Analysis Identifies Genomic Regions Controlling Domestication Traits in Intermediate Wheatgrass

by Prabin Bajgain and James A. Anderson

Agriculture 2021, 11(7), 667; https://doi.org/10.3390/agriculture11070667 - 15 Jul 2021

Cited by 11 | Viewed by 3334

Abstract

Intermediate wheatgrass (IWG) is a perennial forage grass undergoing a rigorous domestication as a grain crop. As a young grain crop, several agronomic and domestication traits need improvement for IWG to be relevant in current agricultural landscapes. This study genetically maps six domestication [...] Read more.

Intermediate wheatgrass (IWG) is a perennial forage grass undergoing a rigorous domestication as a grain crop. As a young grain crop, several agronomic and domestication traits need improvement for IWG to be relevant in current agricultural landscapes. This study genetically maps six domestication traits in the fourth cycle IWG breeding population at the University of Minnesota: height, seed length, seed width, shattering, threshability, and seed mass. A weak population structure was observed and linkage disequilibrium (r²) declined rapidly: 0.23 mega base pairs at conventional r² value of 0.2. Broad-sense heritabilities were overall high and ranged from 0.71–0.92. Association analysis was carried out using 25,909 single SNP markers and 5379 haplotype blocks. Thirty-one SNP markers and 17 haplotype blocks were significantly associated with the domestication traits. These associations were of moderate effect as they explained 4–6% of the observed phenotypic variation. Ten SNP markers were also detected by the haplotype association analysis. One SNP marker on Chromosome 8, also discovered in haplotype block analysis, was common between seed length and seed mass. Increasing the frequency of favorable alleles in IWG populations via marker-assisted selection and genomic selection is an effective approach to improve IWG’s domestication traits. Full article

(This article belongs to the Special Issue Trait Genetics and Molecular Mapping of Genes in Food and Forage Crops)

► Show Figures

Figure 1

Figure 1
Scatter plots showing principal component 1 (PC1) plotted against principal component 2 (PC2) (Panel A) and squared allele-frequency correlations (r2) plotted against physical distance (mega base pairs, Mbp) in the UMN_C4 intermediate wheatgrass population (Panel B). The decline of linkage disequilibrium is shown by plotting the LOWESS curve in blue color. To improve the visibility of the curve, the x-axis shows LD decline within 20 Mbp only; a plot with a full range of genome-wide distances is shown in <a href="#app1-agriculture-11-00667" class="html-app">Figure S1</a>. Full article ">Figure 2
Histogram distributions of six domestication traits in the UMN_C4 intermediate wheatgrass population. Dashed red line is the trait median and solid red line is mean. Full article ">Figure 3
Manhattan plots showing significant SNP markers discovered for each trait by association analysis. Dashed red line indicates the Bonferroni threshold at α = 0.05. Full article ">Figure 4
Comparison between the cumulative phenotypic variance explained (R2) by significant SNP markers and haplotype blocks domestication traits in the UMN_C4 intermediate wheatgrass population. Error bars represent standard deviations. Full article ">

17 pages, 278 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

The Effects of Soil Compaction and Different Tillage Systems on the Bulk Density and Moisture Content of Soil and the Yields of Winter Oilseed Rape and Cereals

by Krzysztof Orzech, Maria Wanic and Dariusz Załuski

Agriculture 2021, 11(7), 666; https://doi.org/10.3390/agriculture11070666 - 14 Jul 2021

Cited by 25 | Viewed by 6724

Abstract

Progressive soil compaction is a disadvantage of intensive tillage. Compaction exerts a negative impact on the physical properties of soil and decreases crop performance. The adverse effects of soil compaction can be mitigated by replacing conventional tillage with simplified tillage techniques. Simplified tillage [...] Read more.

Progressive soil compaction is a disadvantage of intensive tillage. Compaction exerts a negative impact on the physical properties of soil and decreases crop performance. The adverse effects of soil compaction can be mitigated by replacing conventional tillage with simplified tillage techniques. Simplified tillage exerts a protective effect on soil, reduces production costs and preserves agricultural ecosystems. The aim of this study was to determine the influence of compaction and different tillage methods on the bulk density and moisture content of soil. The experimental factors were as follows: Soil compaction before sowing (non-compacted control treatment and experimental treatments where soil was compacted after the harvest of the preceding crop) and four different methods of seedbed preparation in a three-field rotation system (winter oilseed rape, winter wheat, spring barley). The influence of compaction on the bulk density and moisture content of soil varied across the rotated crops and their developmental stages. Soil compaction had no significant effect on the analyzed parameters in the cultivation of winter oilseed rape. In treatments sown with winter wheat, soil compaction resulted in significantly lower soil density and significantly higher soil moisture content. In plots sown with spring barley, soil compaction led to a significant increase in the values of both parameters. The average bulk density of soil after various tillage operations in the examined crop rotation system ranged from 1.49–1.69 g·m⁻³ (winter oilseed rape), 1.47–1.59 g·m⁻³ (winter wheat), 1.47–1.61 g·m⁻³ (spring barley). The bulk density and moisture content of soil were lowest after conventional tillage (control treatment) and higher after simplified tillage. Regardless of soil compaction, the greatest reduction in winter oilseed rape yields was noted in response to skimming, harrowing and the absence of pre-sowing plowing. Spring barley yields were higher in non-compacted treatments, whereas the reverse was observed in winter wheat. Chisel plowing and single plowing induced the greatest decrease in wheat yields relative to conventional tillage. Single plowing significantly decreased the grain yield of spring barley relative to the tillage system that involved skimming and fall plowing to a depth of 25. Full article

(This article belongs to the Section Agricultural Soils)

11 pages, 2557 KiB

Open AccessArticle

Design and Experimental Research on Soil Covering Device with Linkage and Differential Adjustment of Potato Planter

by Zhiqi Zheng, Zuoli Fu, Chenyang Wang, Yuxiang Huang and Jinpu He

Agriculture 2021, 11(7), 665; https://doi.org/10.3390/agriculture11070665 - 14 Jul 2021

Cited by 5 | Viewed by 3187

Abstract

When the potato planter works on sloping field, it will cause problems such as poor film mulching quality due to the difference in volume of soil covering both sides of the discs and the inconvenient adjustment of the soil covering disc. The soil [...] Read more.

When the potato planter works on sloping field, it will cause problems such as poor film mulching quality due to the difference in volume of soil covering both sides of the discs and the inconvenient adjustment of the soil covering disc. The soil covering device with linkage and differential adjustment was designed to improve the mulching quality. The main research content includes explaining the structure and principle of the soil covering device and analyzing the structural parameters of the adjustment mechanism. The field experiment was completed to verify the performance of soil covering device, which takes the stability coefficient and uniformity coefficient of the volume of covering soil as factors. The result shows the following: (1) The volume of covering soil changes exponentially with the angle of the disc through data fitting, which can standardize the angle of covering disc; and (2) when the angle of disc is 30° and 60°, respectively, the uniformity coefficient of volume of covering soil is lower than 1.4, which has premium soil covering quality. When the angles of the discs on both sides differ greatly, the stability coefficient of volume of covering soil is 0.41, which can meet the requirements of the mulching quality of potato planter. This research provides the technical support for high-quality potato planting. Full article

(This article belongs to the Special Issue Agricultural Structures and Mechanization)

► Show Figures

Figure 1

13 pages, 571 KiB

Open AccessArticle

Economic Returns from Cereal and Cereal/Vetch Forage Crops Grown as Fodder Conservation Options for Beef and Sheepmeat Production

by John W. Piltz, Craig A. Rodham, John F. Wilkins, Belinda F. Hackney and Colin G. Brown

Agriculture 2021, 11(7), 664; https://doi.org/10.3390/agriculture11070664 - 14 Jul 2021

Cited by 6 | Viewed by 2193

Abstract

The economic return from cereal or cereal/vetch crops was determined using previously published and new agronomic and herbage quality data from experiments conducted at four sites across southern New South Wales, Australia, over four years (2008 to 2011), to evaluate the agronomic and [...] Read more.

The economic return from cereal or cereal/vetch crops was determined using previously published and new agronomic and herbage quality data from experiments conducted at four sites across southern New South Wales, Australia, over four years (2008 to 2011), to evaluate the agronomic and quality parameters of two wheat (Triticum aestivum L.), two barley (Hordeum vulgare L.), two oat (Avena sativa L.), and one triticale (x Triticosecale) variety, grown as monocultures or in combination with purple vetch (Vicia benghalensis L.). The crops (n = 193) were harvested at different stages of cereal maturity and ranged in metabolisable energy (ME) from 6.9 to 13.1 MJ/kg DM and crude protein (CP) content from 49.8 to 215.4 g/kg DM. Individual crop ME and CP content was used to predict dry matter intake and liveweight gain using Grazfeed decision support tool, assuming the forages were fed as the sole diet to either crossbred lambs or British breed steers, with initial liveweights of 30 or 300 kg respectively. Animal parameters and yield were used to estimate gross margins (GM) for each crop based on estimated fixed and variable costs, including sowing and fertiliser costs, and harvesting and feedout costs. Feed quality determined animal production and potential income per animal, while yield determined potential income per hectare for any given level of animal production. Across the three years GM ranged from −$1489 to $5788 in sheep and from −$1764 to $647 in cattle. Reducing costs or increasing livestock value improved the GM. The highest GM were for lambs fed crops with high ME, adequate CP, and good yields. Increasing yield reduced the GM when growth rates were low, and costs exceeded the value of liveweight gain. Full article

(This article belongs to the Special Issue Forage Quality, Conservation and Evaluation in Ruminant Production Systems)

► Show Figures

Figure 1

14 pages, 6033 KiB

Open AccessArticle

Establishment of a Bivector Genetic Transformation System in Recalcitrant Maize Inbred Lines

by Yajing Gu, Xuan Chen, Rentao Song and Weiwei Qi

Agriculture 2021, 11(7), 663; https://doi.org/10.3390/agriculture11070663 - 14 Jul 2021

Cited by 3 | Viewed by 2966

Abstract

Maize is an important grain crop with high nutritional value. An effective transformation system is crucial for the genetic improvement of maize traits, but many important maize inbred lines remained recalcitrant to transformation. In this study, we developed a bivector transformation system that [...] Read more.

Maize is an important grain crop with high nutritional value. An effective transformation system is crucial for the genetic improvement of maize traits, but many important maize inbred lines remained recalcitrant to transformation. In this study, we developed a bivector transformation system that worked well in two recalcitrant maize inbred lines. This system included an induction vector (ZmBBM-ZmWUS) and an indicator vector (GFP), using microprojectile bombardment technology combined with Agrobacterium-mediated transformation. We found that the Zheng58 and Mo17 recalcitrant inbred lines could be transformed with this system. The whole transformation cycle lasted only 52 days, 38 days less than the traditional transformation cycle. Additionally, it was possible to eliminate inference of the induction vector and obtained progenies with only the target gene. Our results suggested that the bivector system was an optimization of the current maize transformation methods and could potentially be used in genetic improvement of maize inbred lines. Full article

► Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
Gene expression level of ZmCTA1 and ZmPLTP in various maize tissues. (a,b) RT-qPCR confirmed the expression level of ZmCTA1 and ZmPLTP in the root, stem, leaf, silk, ear, anther, immature seed, embryo and calli of maize. Actin was used as an internal control. Date are the mean values with standard error of mean (SEM), n = 3 individuals. Full article ">Figure 2
Vector maps for the genetic transformation system. BBM, BABY BOOM; WUS, WUSCHEL; GFP, Green fluorescent protein; NOSpro, Nopaline synthase promoter; CTA1pro, maize Chitinase A1 promoter; Axig1pro, Auxin-inducible promoter; PLTPpro, Phospholipid transferase protein promoter; 35Spro, the cauliflower mosaic virus 35S promoter; TNOS, Nopaline synthase terminator; TRbst, Rbst terminator; T35S, cauliflower mosaic virus 35S terminator; BAR, Bialaphos resistance; HPT, Hygromycin phosphotransferase; LB, left border; RB, right border. A summary of the primers is given in <a href="#app1-agriculture-11-00663" class="html-app">Table S2</a>. (a) T-DNA composition for the pHB-CB-NW vector. This vector shows that ZmCTA1pro drives ZmBBM and that NOSpro drives ZmWUS. (b) T-DNA composition for the pHB-CB-AW vector. In this vector, ZmCTA1pro drives ZmBBM and ZmAxig1pro drives ZmWUS. (c) T-DNA composition for the pHB-PB-AW vector. This vector shows that ZmPLTPpro drives ZmBBM and that ZmAxig1pro drives ZmWUS. (d) T-DNA composition for the pCA-GFP vector. This vector is a directive reporting pCAMBIA3301 vector including GFP driven by the 35S promoter (35Spro::GFP). (e) T-DNA composition for the pHB-CB-NW-GFP vector. In this vector, ZmCTA1pro drives ZmBBM, 35Spro drives GFP, and NOSpro drives ZmWUS. (f) T-DNA composition for the pHB-CB-NW-GFP vector. In the pHB-CGA vector, ZmCTA1pro drives ZmBBM, 35Spro drives GFP, and ZmAxig1pro drives ZmWUS. (g) T-DNA composition for the pHB-PB-AW-GFP vector. This vector shows that PLTPpro drives ZmBBM, 35Spro drives GFP, and ZmAxig1pro drives ZmWUS. Full article ">Figure 3
Culture process of the bivector maize genetic transformation system. Embryos were isolated from the seeds of the Zheng58 inbred line at 14–16 DAP. The length of immature embryos was 1.8–2.2 cm. The pHB-CB-NW vector was transformed into immature embryos by microprojectile bombardment technology. The pCA-GFP vector was integrated into the maize genome via Agrobacterium infection. There are a series of culture media and conditions to obtain transgenic plants. Full article ">Figure 4
Development of transgenic plants. (a) The calli were sprouted on the pre-regeneration medium. (b) Most embryos initially induced roots on dark regeneration medium. (c) Embryos absorbed light to grow plants on light regeneration medium and were cultured in growth chambers. (d) Transgenic plants were successfully obtained from immature maize embryos of Zheng58 in a greenhouse. Full article ">Figure 5
Progeny analysis of transgenic Zheng58 plants. Zheng58 (Z58) served as a negative control. (a) PCR identification concerning the 4 lines of transgenic Zheng58. The plasmid of the pCA-GFP vector was treated as a positive control. (b) Genomic DNA of transgenic Zheng58 plants digested with HindIII for Southern blot analysis. (c) Genomic DNA of transgenic Zheng58 plants digested with EcoRI for Southern blot analysis. Red arrows identify the gene copies. (d) Comparison of the GFP expression level in the leaf tissue of Z58 and transgenic Zheng58. The transcript levels were normalized according to Actin. Values are the means with SEM; n = 3 individuals. See <a href="#app1-agriculture-11-00663" class="html-app">Table S2</a> for primers. Full article ">Figure 6
Progeny segregation of the transgenic Zheng58 lines. Progeny transgenic Zheng58 of lines 1#, 2#, 3#, and 4# contained ZmCTA1pro::BBM-NOSpro::WUS or 35Spro::GFP. Seeds were recognized by amplifying GFP and HPT in the descendants of each line. The pCA-GFP vector and pHB vector were treated as positive controls. Zheng58 (Z58) was served as a negative control. See <a href="#app1-agriculture-11-00663" class="html-app">Table S2</a> for primers. Full article ">

19 pages, 1313 KiB

Open AccessArticle

Effects of Rocket Seed Oil, Wheat Germ Oil, and Their Mixture on Growth Performance, Feed Utilization, Digestibility, Redox Status, and Meat Fatty Acid Profile of Growing Rabbits

by Sabrin Abdelrahman Morshedy, Ahmed M. Abdelmodather, Mohamed M. Basyony, Soliman A. Zahran and Mohamed A. Hassan

Agriculture 2021, 11(7), 662; https://doi.org/10.3390/agriculture11070662 - 14 Jul 2021

Cited by 11 | Viewed by 3991

Abstract

Vegetable oils are a source of natural antioxidants, including tocopherols, sterols, phenolic compounds, coenzymes, and polyunsaturated fatty acids that provide nutritional value, organoleptic properties, and significantly delay or prevent lipid oxidation. Eighty-four V-line rabbits at 5 weeks of age with an initial body [...] Read more.

Vegetable oils are a source of natural antioxidants, including tocopherols, sterols, phenolic compounds, coenzymes, and polyunsaturated fatty acids that provide nutritional value, organoleptic properties, and significantly delay or prevent lipid oxidation. Eighty-four V-line rabbits at 5 weeks of age with an initial body weight (BW) of 535.60 ± 13.48 g were assigned randomly to four experimental groups (seven replicates in each group with three rabbits each). The first group served as a control and received 0.3 mL/kg BW of distilled water (CON), while the second and third groups received 0.3 mL/kg BW of rocket seed oil (RSO) and wheat germ oil (WGO), respectively. The fourth group received a mixture of oils consisting of 0.15 mL of RSO and 0.15 mL of WGO/kg BW (MOs). The experiment lasted 7 weeks. The study investigated the effects of RSO, WGO, and their mixture on growth performance, feed utilization, antioxidant status, and immune response of growing rabbits. The results indicated that the rabbits that were administered orally with RSO and WGO or their mixture had higher (p ≤ 0.05) final BW, weight gain, and average daily gain when compared to the control group. In addition, the feed conversion ratio improved significantly with RSO, WGO, and MOs treatments. Different oil treatments improved nutrient digestibility, nutritive value, and nitrogen balance. Moreover, the rabbits that received RSO, WGO, and their mixture had an improvement the meat fatty acid composition compared to the control rabbits. Oral administration of RSO, WGO, and their mixture significantly improved serum protein fractions, decreased blood urea nitrogen, and had a positive effect on serum total lipids, HDL-c, and LDL-c. Furthermore, the treatments of RSO, WGO, and MOs had a significant improvement in the antioxidative status and immune response. Full article

(This article belongs to the Special Issue Safety and Efficacy of Feed Additives in Animal Production)

► Show Figures

Figure 1

Figure 1
Body weight of V-line growing rabbits (5–12 weeks of age) that were administered orally with rocket seed oil, wheat germ oil, and their mixture. Columns marked with different superscripts are significantly different at p ≤ 0.05. Full article ">Figure 2
Nutritive value and digestible energy of experimental diets of V-line growing rabbits (5–12 weeks of age) that were administered orally with rocket seed oil, wheat germ oil, and their mixture. Columns marked with different superscripts are significantly different at p ≤ 0.05. TDN: Total digestible nutrients; DCP: Digestible crude protein; NR: Nutritive value; DE: Digestible energy. Full article ">Figure 3
Meat fatty acid profile and lipids content of V-line growing rabbits (5–12 weeks of age) that were administered orally with rocket seed oil, wheat germ oil, and their mixture. Columns marked with different superscripts are significantly different at p ≤ 0.05. SFA: Saturated fatty acids; UFA: Unsaturated fatty acids; MUFA: Monounsaturated fatty acids; PUFA: Polyunsaturated fatty acids; n-3: Omega-3; n-6: Omega-6. Full article ">Figure 4
Serum thiobarbituric acid reactive substances and antioxidants status of V-line growing rabbits (5–12 weeks of age) that were administered orally with rocket seed oil, wheat germ oil, and their mixture. Columns marked with different superscripts are significantly different at p ≤ 0.05. CAT: Catalase; SOD: Superoxide dismutase; TAC: Total antioxidant capacity; TBARs: Thiobarbituric acid reactive substances. Full article ">

14 pages, 2974 KiB

Open AccessArticle

The Study of Chicken Manure and Steel Slag Amelioration to Mitigate Greenhouse Gas Emission in Rice Cultivation

by Muhammad Iqbal Fauzan, Syaiful Anwar, Budi Nugroho, Hideto Ueno and Yo Toma

Agriculture 2021, 11(7), 661; https://doi.org/10.3390/agriculture11070661 - 13 Jul 2021

Cited by 3 | Viewed by 3453

Abstract

Organic matter, fertilizers, and soil amendments are essential for sustainable agricultural practices to guarantee soil productivity. However, these materials can increase the emission of greenhouse gases (GHGs) such as CH₄ and N₂O. Thus, technologies for reducing GHG emissions in concert [...] Read more.

Organic matter, fertilizers, and soil amendments are essential for sustainable agricultural practices to guarantee soil productivity. However, these materials can increase the emission of greenhouse gases (GHGs) such as CH₄ and N₂O. Thus, technologies for reducing GHG emissions in concert with the increase in rice production from rice fields are needed. The objectives of this study were to determine the best chicken manure (CM) and steel slag (SS) combination to mitigate CH₄, N₂O, and CO₂ emissions in an incubation experiment, to identify the best CM:SS ameliorant mixture to mitigate CH₄ and N₂O, and to evaluate dry biomass and grain yield in a pot experiment. A randomized block design was established with four treatments, namely conventional (chemical fertilizer only) and three combinations of different ratios of CM and SS (1:1, 1:1.5, and 1:2.5), with five replications in a pot experiment. CM:SS (1:2.5) was identified as the best treatment for mitigating CH₄, N₂O, and CO₂ in the incubation experiment. However, CM:SS (1:1.5) was the best CM and SS ameliorant for mitigating CH₄ and N₂O in the pot experiment. The global warming potential of CH₄ and N₂O revealed that CM:SS (1:1.5) had the lowest value. None of the combinations of CM and SS significantly increased dry biomass and grain yield. Full article

(This article belongs to the Special Issue Sustainable Rice Farming and Greenhouse Gas Emissions)

► Show Figures

Figure 1

Figure 1
CH4 (a), N2O (b), and CO2 (c) flux during the incubation experiment. SO: soil only, CM: chicken manure, SS: steel slag. CM:SS is the weight given ratio between chicken manure and steel slag. Error bars represent standard error. Full article ">Figure 2
Soil pH (a), NH4+-N (b), NO3−-N (c), and Fe2+ (d) concentrations of soil in each treatment during the pot experiment. All values are expressed as mean. SO: soil only, CM: chicken manure, SS: steel slag. Error bars represent standard error. Full article ">Figure 3
CH4 flux (a) and N2O flux (b) in each treatment during the pot experiment. All values are expressed as means. Conv: conventional, CM: chicken manure, SS: steel slag, SF: supplementary fertilization, D: time when the pot was dried. Error bars represent standard error. Full article ">Figure 4
Cumulative CH4 (a) and N2O (b) emissions in each treatment during the pot experiment. All values are expressed as mean. Conv: conventional, CM: chicken manure, SS: steel slag. Error bars represent standard error. Different letters among the treatments indicate a significant difference (p < 0.05). Full article ">Figure 5
Soil temperature (a), Soil water pH (b), NH4+-N (c) and NO3−-N (d) concentrations, and Eh (e) in each treatment during the pot experiment. All values are expressed as mean. Conv: conventional, CM: chicken manure, SS: steel slag, SF: supplementary fertilization, D: the time when the pot was dried. Error bars represent standard error. Full article ">Figure 6
Plant height (a), chlorophyll content (b), number of tillers (c) in each treatment during the pot experiment. All values are expressed as mean. Conv: conventional, CM: chicken manure, SS: steel slag, SF: supplementary fertilization, D: the time when the pot was dried. Error bars represent standard error. Full article ">

10 pages, 1563 KiB

Open AccessArticle

Pilot Study to Evaluate Performance of Frost-Yuzu Fruit Trees under Protected Cultivation

by Byeong-Sam Kim, Bo-Bae Lee, Seok-Kyu Jung and Hyun-Sug Choi

Agriculture 2021, 11(7), 660; https://doi.org/10.3390/agriculture11070660 - 13 Jul 2021

Cited by 1 | Viewed by 3131

Abstract

This study was initiated to observe the performance of yuzu (Citrusjunos Sieb. ex Tanaka) fruit trees when affected by a late freezing in 2018 and to evaluate the recovery of frost-damaged trees during post management under protected cultivation. A—4.9 °C of [...] Read more.

This study was initiated to observe the performance of yuzu (Citrusjunos Sieb. ex Tanaka) fruit trees when affected by a late freezing in 2018 and to evaluate the recovery of frost-damaged trees during post management under protected cultivation. A—4.9 °C of minimum daily temperature and 40-day drought occurred during dormancy, which then received heavy precipitation between early- and mid-March, with 15 m s⁻¹ more than maximum instantaneous wind speeds frequently observed. This resulted in observed decreases in height, width and volume as well as in fruiting, fruit weight and yield, as well as yield index in 60–90% defoliated yuzu trees, in addition to higher rates of shoot dieback compared to trees that experienced only 0–30% defoliation. Lower performance and recovery rates of trees grown on flat land compared to trees on sloped land were also observed. Tree and net windbreaks did not significantly affect tree vegetative growth and fruit productivity but were found to have lowered shoot mortality in 2018 and 2019. Mulch with an irrigation after freezing or foliar urea application was shown to effectively increase vegetative tree growth and fruit productivity and reduce shoot mortality. Full article

(This article belongs to the Special Issue Organic Management and Productivity of Tree Crops)

► Show Figures

Figure 1

12 pages, 2396 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Phenolic Response to Walnut Anthracnose (Ophiognomonia leptostyla) Infection in Different Parts of Juglans regia Husks, Using HPLC-MS/MS

by Aljaz Medic, Anita Solar, Metka Hudina and Robert Veberic

Agriculture 2021, 11(7), 659; https://doi.org/10.3390/agriculture11070659 - 13 Jul 2021

Cited by 15 | Viewed by 3756

Abstract

This study compares the individual phenolic response of husk tissues of Juglans regia L., infected to different degrees of severity with walnut anthracnose, which is one of the most serious and widespread walnut diseases worldwide. A comparison among three differently susceptible cultivars, ‘Franquette’, [...] Read more.

This study compares the individual phenolic response of husk tissues of Juglans regia L., infected to different degrees of severity with walnut anthracnose, which is one of the most serious and widespread walnut diseases worldwide. A comparison among three differently susceptible cultivars, ‘Franquette’, ‘Milotai 10’ (‘M10’), and ‘Milotai intenziv’ (‘M10-37’), is made. In our methodology, high performance liquid chromatography coupled with mass spectrometry is used to identify and quantify the compounds. Our results show that flavanols, flavonols, and naphthoquinones account for more than 95% of the phenolic compounds identified in the walnut husk. The higher total analyzed phenolic content in tissues is more affected by walnut anthracnose confirmed that phenolics play a major role in the plant’s response against pathogens. A difference between cultivars is observed, since French cultivar ‘Franquette’ responds differently to walnut anthracnose infection than Hungarian cultivars ‘M10’ and ‘M10-37’. Naphthoquinones and flavanols have a very similar response to walnut anthracnose infection. The resistance of cultivars may be due to the reaction time of the plant and the speed with which it recognizes the pathogen and responds quickly to the infection by containing it while it has not yet spread. Flavonols may be the most important phenolic compounds in disease control, since they respond more rapidly to infection than flavanols and naphthoquinones. They also play an inhibitory role in the early stages of viral and bacterial infections. Full article

(This article belongs to the Special Issue Development and Cultivar Improvement of Nut Crops)

► Show Figures

Figure 1

Figure 1
Different parts of walnut tissue were sampled. Red circle (S): inner spot of infected tissue; blue circle (AI): outer margin of infected tissue; yellow circle (AH): healthy tissue surrounding the infection. Full article ">Figure 2
Contents of three major groups of phenolics identified in different severity of walnut anthracnose-affected tissues of J. regia husk, between three cultivars: Susceptible ‘M10-37’, semi-susceptible ‘M10’ and least susceptible ‘Franquette’ (in mg/g dry weight). S: inner spot of infected tissue; AI: outer margin of infected tissue; AH: healthy tissue surrounding the infection; H: healthy tissue. Full article ">Figure 3
Dendrogram showing the grouping of naphthoquinones (A) and flavanols (B) between the severities of walnut anthracnose-affected tissues of three cultivars, using Ward’s method (squared Euclidean distance) based on total phenolic compounds. Data are standardized (µ = 0, σ = 1). S: inner spot of infected tissue; AI: outer margin of infected tissue; AH: healthy tissue surrounding the infection; H: healthy tissue. Full article ">Figure 4
Heat map showing relative content of the phenolic compound identified between cultivars from highest to lowest content between columns. Red: highest concentration; green: lowest concentration. S: inner spot of infected tissue; AI: outer margin of infected tissue; AH: healthy tissue surrounding the infection; H: healthy tissue. Full article ">Figure 5
Contents of flavonols identified in different severity of walnut anthracnose-affected tissues of J. regia husk, between three cultivars: susceptible ‘M10-37’, semi-susceptible ‘M10’ and least susceptible ‘Franquette’ (in mg/g dry weight). S: inner spot of infected tissue; AI: outer margin of infected tissue; AH: healthy tissue surrounding the infection; H: healthy tissue. Full article ">Figure 6
Contents of selected naphthoquinones and flavanols identified in different severity of walnut anthracnose-affected tissues of J. regia husk, between three cultivars: susceptible ‘M10-37’, semi-susceptible ‘M10’ and least susceptible ‘Franquette’ (in mg/g dry weight). S: inner spot of infected tissue; AI: outer margin of infected tissue; AH: healthy tissue surrounding the infection; H: healthy tissue. Full article ">

23 pages, 5661 KiB

Open AccessArticle

Prediction of Key Crop Growth Parameters in a Commercial Greenhouse Using CFD Simulation and Experimental Verification in a Pilot Study

by Subin Mattara Chalill, Snehaunshu Chowdhury and Ramanujam Karthikeyan

Agriculture 2021, 11(7), 658; https://doi.org/10.3390/agriculture11070658 - 13 Jul 2021

Cited by 7 | Viewed by 3717

Abstract

Controlled crop growth parameters, such as average air velocity, air temperature, and relative humidity (RH), inside the greenhouse are necessary prerequisites for commercial greenhouse operation. Frequent overshoots of such parameters are noticed in the Middle East. Traditional heating ventilation and air-conditioning (HVAC) systems [...] Read more.

Controlled crop growth parameters, such as average air velocity, air temperature, and relative humidity (RH), inside the greenhouse are necessary prerequisites for commercial greenhouse operation. Frequent overshoots of such parameters are noticed in the Middle East. Traditional heating ventilation and air-conditioning (HVAC) systems in such greenhouses use axial fans and evaporative cooling pads to control the temperature. Such systems fail to respond to the extreme heat load variations during the day. In this study, we present the design and implementation of a single span, commercial greenhouse using box type evaporative coolers (BTEC) as the backbone of the HVAC system. The HVAC system is run by a fully-automated real time feedback-based climate management system (CMS). A full-scale, steady state computational fluid dynamics (CFD) simulation of the greenhouse is carried out assuming peak summer outdoor conditions. A pilot study is conducted to experimentally monitor the environmental parameters in the greenhouse over a 20-h period. The recorded data confirm that the crop growth parameters lie within their required ranges, indicating a successful design and implementation phase of the commercial greenhouse on a pilot scale. Full article

(This article belongs to the Special Issue Future Development Trends of Intelligent Greenhouses)

► Show Figures

Figure 1

10 pages, 1261 KiB

Open AccessArticle

Profit Efficiency of Rice Farms in Wet-Season Lowlands in Champhone District, Savannakhet Province, Lao PDR

by Sengphachan Khounthikoumane, Jae Bong Chang and Yoonsuk Lee

Agriculture 2021, 11(7), 657; https://doi.org/10.3390/agriculture11070657 - 12 Jul 2021

Cited by 2 | Viewed by 3842

Abstract

This study analyzed factors affecting profit efficiency of rice farms in wet-season lowlands in the Champhone District of Savannakhet Province in the Lao People’s Democratic Republic based on a farmer’s decision to maximize profits. The profit efficiency approach has an advantage in that [...] Read more.

This study analyzed factors affecting profit efficiency of rice farms in wet-season lowlands in the Champhone District of Savannakhet Province in the Lao People’s Democratic Republic based on a farmer’s decision to maximize profits. The profit efficiency approach has an advantage in that it provides insights into both inputs and outputs. To analyze profit efficiency, the stochastic production frontier model with assumptions about the time period and types of inputs was applied in the study. The study found similar results to previous studies related to efficiency measurements using a stochastic frontier analysis. Rice production and selling prices have positive signs with respect to the rate of return; however, costs of labor, seed, irrigation, fertilizers, and maintenance have negative signs with respect to the rate of revenue. However, the results from the inefficiency model showed the different role of education. The previous studies found that education level did not play an important role in improving rice productivity in Laos, however, the present study found that education level played a significant role in increasing profits. Full article

(This article belongs to the Special Issue Agricultural Policy and Farmer Behavior)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Agriculture, Volume 11, Issue 7 (July 2021) – 115 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI