CN116491378B - A method for cultivating summer corn in mild to moderate saline-alkali soil - Google Patents

Abstract

The invention discloses a method for cultivating summer corn in mild to moderate saline-alkali soil, which includes crushing wheat straw and spreading it evenly on cultivated land, spreading fertilizer, subsoiling and rotary tilling the soil, turning all the fertilizer into the soil, and then forming ridges; The fertilizer includes humic acid compound fertilizer and microbial inoculants; summer corn seeds and sorghum seeds are coated or seed-dressed, summer corn seeds are sown in furrows, and sorghum ridges are sown; field management is performed after sowing, and summer corn and sorghum seeds are sown. Harvested separately at maturity. The cultivation method of the present invention can prevent the return of salt in the root zone of crops, promote the healthy development of the root system of summer corn, increase the photosynthetic rate of the plant, increase the accumulation of dry matter, and increase the yield of summer corn in saline-alkali soil.

Description

A method for cultivating summer corn in mild to moderate saline-alkali soil

Technical field

The invention relates to the technical field of summer corn planting, and specifically relates to a summer corn cultivation method in mild to moderate saline-alkali soil.

Background technique

Saline soil is widely distributed in China, and the current salinized area of cultivated land reaches 9.209 million hm ² , accounting for 6.62% of the national cultivated land area. The efficient use of saline-alkali land resources is of great significance to increasing my country's cultivated land area, improving my country's agricultural production capacity, and ensuring my country's food security. Summer corn has a wide planting area in mild to moderate saline-alkali land. When corn is exposed to a saline-alkali environment, osmotic stress occurs in the root system, and ABA accumulates in large quantities, inhibiting multiple metabolic processes such as cell expansion, cell wall synthesis, protein synthesis, and stomatal conductance. Secondly, It is the balance between the production and removal of reactive oxygen species (ROS) that is broken and causes oxidative stress. Both of them jointly affect the normal function of the root system. This results in weak summer corn seedlings, poor root development, and poor water nutrient absorption in saline-alkali lands, which in turn affects the yield of summer corn in saline-alkali lands. The response measures in the existing technology are mainly soil improvement, large-scale salt washing and the selection of salt-alkali tolerant varieties. These saline-alkali land improvement methods have problems such as high investment costs, slow improvement speed, taking 3-5 years to be effective, and difficulty in comprehensive promotion. . Improved planting methods are simple and easy to promote. Therefore, according to the salt stress characteristics of the root zone of saline-alkali soil, it is particularly important to develop efficient and low-cost planting methods to alleviate the salt-alkali stress of summer corn. It has great industrial practical value for the summer corn industry.

Therefore, there is an urgent need for a cultivation method for summer corn in mild to moderate saline-alkali soil that promotes root development, prevents salt return in the root zone, and increases yield. It is of great significance for increasing the planting area and yield of summer corn in saline-alkali soil.

Contents of the invention

In view of the above-mentioned prior art, the purpose of the present invention is to overcome the poor root development, reduced plant photosynthetic performance, reduced biomass and yield loss of summer corn caused by salt stress in the current saline-alkali land, and provide a summer corn cultivation method in mild to moderate saline-alkali land.

In order to achieve the above objects, the present invention adopts the following technical solutions:

A method for cultivating summer corn in mild to moderate saline-alkali soil, which is characterized by including the following steps:

(1) Crush the wheat straw and spread it evenly on the cultivated land, spread the fertilizer, deep loosen and rotary till the soil, turn all the fertilizer into the soil, and then make ridges; the fertilizer includes humic acid compound fertilizer and microbial inoculant ;

(2) Coat or dress summer corn seeds and sorghum seeds, sow summer corn seeds in furrows and sow sorghum seeds on ridges;

(3) Field management is carried out after sowing, and summer corn and sorghum are harvested at the maturity stage respectively.

Preferably, in step (1), the straw chopping qualification rate is ≥90%, the throwing unevenness rate is ≤10cm, and the crushed straw length is ≤10cm.

Preferably, in step (1), the dosage _of the humic acid compound fertilizer is 750kghm ^-2 , wherein N: _P2O5 : _K2O =26:10:12; the dosage of the microbial inoculant is 150Lhm ^-2 .

Preferably, in step (1), the number of effective viable bacteria in the microbial agent is ≥3 billion/ml, fulvic acid ≥60g/L, organic matter ≥100g/L, N≥30g/L, P ₂ O ₅ ≥ 20g/L, K ₂ O≥10g/L, B≥2g/L.

Preferably, in step (1), the ridge specifications include a ridge height of 15 cm, a ridge width of 40 cm, and a furrow width of 20 cm.

Preferably, in step (1), the depth of subsoiling is 30cm ~ 35cm, the depth of rotary tillage is ≥ 10cm, the quality of subsoiling needs to comply with the regulations of DB37/T3562 and DB37/T3563, the particle size of the soil after rotary tillage is ≥ 4cm, and the quality of soil blocks ≤0.5%. If the rotary tillage effect does not meet the technical requirements, the rotary tillage can be repeated until it meets the sowing requirements.

Preferably, in step (2), the summer corn seeds are summer corn seeds with a germination rate of ≥85% when the soil salt content is 0.3%.

Preferably, in step (2), the sorghum seeds are selected from varieties with short stalks and a growth period similar to the summer corn seeds.

Preferably, in step (2), when the moisture is insufficient, the supplementary irrigation amount is 30mm.

Preferably, in step (2), when the summer corn variety is compact, the planting density is 60,000 plants hm ^-2 to 75,000 plants hm ^-2 ; when the summer corn variety is semi-compact, the planting density is 52,500 plants. hm ^-2 ~ 60,000 plants hm ^-2 .

Preferably, in step (2), the coating technical requirements should comply with the regulations of GB/T15671, and the use of seed dressing agents should comply with the regulations of NY/T1276.

Preferably, in step (3), the herbicide is sprayed after sowing and before emergence to seal the weeds.

Preferably, in step (3), pesticides are sprayed to prevent pests and diseases during the trumpet period.

Preferably, in step (3), the use of herbicides should comply with the regulations of NY/T1997, and safe and efficient power spraying machinery should be used.

Preferably, in step (3), the pesticide is mixed with 1000 times liquid of 10% difenoconazole water-dispersible granules and 3000 times liquid of 200gL ^-1 chlorantraniliprole suspension.

Beneficial effects of the present invention:

1. Utilize the characteristics of salt accumulation on the soil surface and the water and salt migration law of "salt climbs to high places" to make the salt in the ditch accumulate on the ridges, reduce the soil salt content in the planting area, and at the same time receive more rainwater. Strengthen salt leaching to promote root development and increase yield. At the same time, sorghum is planted on the ridges to absorb salt and transfer salt out of the field.

2. The cultivation method of the present invention is easy to operate, can be mechanized, has low cost, stabilizes production and increases efficiency, and is of great significance to the development of the summer corn industry in saline-alkali soils.

3. The cultivation method of the present invention can prevent the return of salt in the root zone of crops, promote the healthy development of the root system of summer corn, increase the photosynthetic rate of the plant, increase the accumulation of dry matter, increase the yield of summer corn in saline-alkali soil, and has the characteristics of cost saving, efficiency improvement, and ecological environmental protection. , simple and easy to implement, stable production and increased efficiency, etc., are of great significance to the development of my country's summer corn industry.

Description of the drawings

Figure 1 shows the field planting model;

Figure 2 shows the impact of planting methods on soil moisture content in planting rows (A) and between rows (B) during the silking period of summer corn;

Figure 3 shows the effect of planting methods on the vertical distribution characteristics of Na ⁺ during the silking stage of summer corn;

Figure 4 shows the influence of planting methods on the vertical distribution characteristics of HCO ₃ ^- during the silking stage of summer corn;

Figure 5 shows the effect of planting methods on the vertical distribution characteristics of summer corn root length density;

Figure 6 shows the impact of planting methods on summer corn biomass.

Detailed ways

It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present application. Unless otherwise defined, all technical and scientific terms used herein have the same meanings commonly understood by one of ordinary skill in the art to which this application belongs.

In order to enable those skilled in the art to understand the technical solutions of the present application more clearly, the technical solutions of the present application will be described in detail below with reference to specific embodiments.

The test materials used in the examples of the present invention are all conventional test materials in this field and can be purchased through commercial channels.

The humic acid compound fertilizer used in the present invention is purchased from Shandong Agricultural University Fertilizer Technology Co., Ltd., with the _trade name of controlled release blended fertilizer, in which N: _P2O5 : _K2O =26:10:12, humic acid ≥3%, silicon ≥2%, zinc ≥0.02%, low chlorine.

The common compound fertilizer used in the present invention is a compound of urea, superphosphate and potassium sulfate, so that N:P ₂ O ₅ :K ₂ O=26:10:12.

The microbial inoculant used in the present invention is purchased from Shandong Agricultural University Fertilizer Technology Co., Ltd., and the trade name is the drip irrigation type compound microbial inoculant, in which the number of effective viable bacteria is ≥3 billion/ml, and the fulvic acid is ≥60g/L. Organic matter ≥ 100g/L, N ≥ 30g/L, P ₂ O ₅ ≥ 20g/L, K _{2 O ≥} 10g/L, B ≥ 2g/L.

The 40% acetonitrile suspension used in the present invention was purchased from Binzhou Zhongxiang Agricultural Chemical Co., Ltd., and its trade name is Yuxingxing.

Both the examples and comparative examples were planted in: Wudi County, Binzhou City, Shandong Province (38°06′N, 117°61′E).

Planting time: Sow on June 18, 2021, harvest on October 9.

The summer corn variety is: JNY658

The sorghum variety is: Jinza No. 37

The planting density of summer corn is 67,500 plants hm ^-2 , the row spacing is 60cm, and the plant spacing is 24.7cm. The planting density of sorghum is 70,000 plants hm ^-2 , the row spacing is 60cm, and the plant spacing is 23.8cm.

One plot is planted in each embodiment or comparative example, and the area of each plot is 150m ² . Each embodiment or comparative example is repeated 3 times, and there is a 1m buffer zone between each plot. The soil properties in this area remain basically the same. The soil nutrient content in the 0-20cm tillage layer before sowing is: organic matter 7.83gkg ^-1 , total nitrogen 0.90gkg ^-1 , available phosphorus 12.4mgkg ^-1 , and available potassium 169.69mgkg ^-1 . The total salt content of the soil in the cultivated layer is 0.25%. The ionic composition of the soil in the experimental field is shown in Table 1.

Table 1 Composition of soil ions in the experimental field

Example 1

A method for cultivating summer corn in mild to moderate saline-alkali soil, including the following steps:

(1) Straw return to the field: crush the wheat straw and spread it evenly on the cultivated land. The passing rate of straw chopping is ≥90%, the uneven scattering rate is ≤10cm, and the length of the crushed straw is ≤10cm;

(2) Fertilization: Spread 750kghm ^-2 of humic acid compound fertilizer on the surface as base fertilizer, of which N:P ₂ O ₅ :K ₂ O = 26:10:12; 150Lhm ^-2 of microbial inoculant, in which the carrier is a water-soluble organic small Molecular amino acids and polysaccharide solutions, effective viable bacterial count ≥ 3 billion/ml, fulvic acid ≥ 60g/L, organic matter ≥ 100g/L, N ≥ 30g/L, P ₂ O ₅ ≥ 20g/L, K ₂ O ≥ 10g /L, B≥2g/L; use a combined subsoiling and soil preparation machine to till the soil, with a subsoiling depth of 30cm to 35cm and a rotary tilling depth of ≥10cm. Pour all humic acid compound fertilizers and microbial inoculants into the soil, leaving no traces on the surface. residue; residue

(3) Riding: Use a ridging machine to perform ridge work. The ridge height is 15cm, the ridge width is 40cm, and the furrow width is 20cm;

(4) Sowing: Use seed coating agents containing difenoconazole, thiamethoxam, tebuconazole and other ingredients to coat summer corn seeds and sorghum seeds. Sow summer corn seeds in furrows and sow sorghum ridges; sow in a timely manner after sowing Irrigation, the irrigation volume is 30mm.

(5) After sowing and before seedling emergence, use a plant protection drone to spray 40% B·Herbaceous Suspension Agent 200-250g/acre for closed weeding;

(6) Prevention and control of pests and diseases: Use 10% difenoconazole water-dispersible granules 1000 times liquid and 200gL ^-1 chlorantraniliprole suspension 3000 times for mixed spraying during the large trumpet period to prevent and control summer corn prone to disease in the later period. pests and diseases;

(7) Summer corn and sorghum are harvested at the maturity stage respectively.

Comparative example 1

The difference from Example 1 is that there is no ridge, summer corn is grown conventionally, microbial inoculants and humic acid compound fertilizer are not spread, and 750kghm ^-2 ordinary compound fertilizer is spread as the base fertilizer.

Comparative example 2

The difference from Example 1 is that no microbial inoculant is applied.

Comparative example 3

The difference from Example 1 is that humic acid compound fertilizer is not spread, and 750kghm ^-2 ordinary compound fertilizer is spread as the base fertilizer.

Test example 1

1.Test method

1.1 Sampling: Sample the root system and soil during the silking stage (R1), select plants with the same growth size, and use a three-dimensional root soil sampling method, with the plant as the center and a soil block with a volume of 10×10× ^10cm3 . The unit is that every 10cm is a soil layer, the depth is taken to 60cm, and the width is taken to 120cm. Then put the root-soil mixture into a 40-mesh small mesh bag, rinse it repeatedly under low water pressure until it is rinsed clean, pick out all the roots, and finally put it into a ziplock bag and store it in a -20°C refrigerator at low temperature. Take soil water and salt samples, every 10cm is a soil layer, and take them to a depth of 60cm. In the flat farming method, soil samples are taken at the planting rows and in the center of the plot (between rows). In the furrow farming method, soil samples of different depths are taken at the bottom of the ditch (planting rows) and on the ridge platform (between rows).

1.2 Measurement items and indicators:

1.2.1 Soil moisture content

Soil was collected during the silk spinning stage (R1), and each treatment was repeated 3 times. The fresh weight of soil samples was weighed immediately after collection and then dried at 75°C to constant weight. The formula for calculating soil moisture content is as follows:

Soil moisture content (%) = (fresh weight - dry weight)/dry weight × 100%

1.2.2Soil pH

Using a water-to-soil ratio of 5:1, add deionized water into a 150ml Erlenmeyer flask with a pipette. Then place the Erlenmeyer flask on the oscillator, and set the oscillation time to 10 minutes. Soil leachate was measured with a pH meter.

1.2.3 Soil ion content

K ⁺ and Na ⁺ are measured using the flame photometer method (K ⁺ has a low concentration in water, so it is calculated as Na ⁺ ); HCO ₃ ^- neutralization titration method using bromophenol blue as the indicator (Bao Shidan, 2000).

1.2.4 Root system morphology

Six plants with even growth were selected and the roots were rinsed repeatedly, and the images were scanned with an EpsonPerfectionTMV700Photo color image scanner (600dpi). The scanned results were obtained using the WinRhizoPro (Régent Instruments, Québec, Canada) root system analysis system to obtain the total root length, total root surface area, and total root length. volume. After scanning, the roots were dried at 80°C to constant weight, and the dry matter weight was weighed.

1.2.5 Leaf area index

At the trumpet stage (V12), silking stage (R1), milk stage (R3), wax stage (R5) and full maturity stage (R6), 6 representative plants were selected for each treatment and the leaves were measured. Length and width, calculate the leaf area of a single plant.

Leaf area of a single plant = leaf length × leaf width × 0.75

Leaf area index = (leaf area of a single plant × number of plants in the plot)/plot area

1.2.6 Net photosynthetic rate of leaves at ear position

A CIRAS-III portable photosynthesis instrument (PPSystems, Hitchin, UK) was used to measure the photosynthetic rate of ear leaves at the R1 stage.

1.2.7 Biomass

Six plants were sampled at V12, R1, R3 and R6. In the R1 stage, the plants were divided into stems, leaves, ears, tassels and bracts. In the R6 stage, the plants were divided into stems, leaves, cobs, tassels and bracts. and grains, first cured at 105°C for 30 minutes, and then dried at 80°C to constant weight.

1.2.8 Grain yield and yield components

In the R6 phase, 9 m ² of summer corn strips were selected from each plot, all ears were harvested, dried in the sun for seed testing, and yield and yield components were measured. Each treatment was harvested in 3 replicates.

2.Test results

2.1 Effect of planting methods on soil moisture and pH distribution characteristics of summer corn fields in saline-alkali land

As the soil depth increases, the soil moisture content gradually increases. The soil layer in the planting row is 0-60cm, and the soil moisture content in furrow cultivation is higher than that in flat cultivation (Figure 2). Soil pH is an important indicator of the degree of soil acidity and alkalinity. As soil depth increases, soil pH gradually increases. The pH values between different soil layers in the planting rows in the 0-40cm soil layer in the R1 and R6 phases are all lower than those in Example 1, and the pH value of the planting rows is lower than that between the rows, indicating that soil salts are transferred from the bottom of the ditch to the top of the ridge (Table 2 ).

Table 2 Changes in pH value of summer corn planting rows and 0-40cm soil layer between rows during silking stage and mature stage

2.2 Effect of planting methods on soil Na ⁺ and HCO ₃ ^- distribution characteristics in summer corn fields in saline-alkali lands

It can be seen from the vertical distribution characteristics of Na ⁺ in the soil that the Na ⁺ content gradually increases with the depth of the soil layer. The difference in Na ⁺ content between planting methods is mainly distributed in the 0-40cm soil layer. From the horizontal direction, the Na + content distribution is significantly reduced where the distance between the furrow and the plant is -10cm to 10cm (the main distribution area of the root system), while the ^{Na + content} in the ridge platform is higher (Figure 3). It can be seen from the vertical distribution characteristics of HCO ₃ ^- in the soil that the HCO ₃ ^- content gradually increases as the depth of the soil layer deepens. From the horizontal direction, the distribution of HCO ₃ ^- in flat cultivation is relatively uniform, while the HCO ₃ ^- content in the main distribution area of the root system in furrow cultivation is lower, and the HCO ₃ ^- content in the ridge platform is higher (Fig. 4).

2.3 Effects of planting methods on root morphology and distribution of summer corn in saline-alkali soil

As can be seen from Figure 5, the root system is mainly distributed in the 0-40cm soil layer. Where the distance from the plant is -10cm to 10cm (the main space for root distribution) in the 0-40cm soil layer, the root length density of trench cultivation is higher than that of flat cultivation. Compared with Comparative Example 1, the root dry weight of Example 1, Comparative Example 2, and Comparative Example 3 increased by 16.51%, 2.79%, and 2.04% respectively, and the root system length increased by 16.29%, 5.02%, and 1.45% respectively; the root system surface area increased respectively. 22.61%, 3.92%, 3.39%; root volume increased by 59.62%, 15.01%, 11.64% (Table 3).

Table 3 Effects of planting methods on individual plant root length, root surface area and root volume during silking stage of summer corn in saline-alkali soil

2.4 Effects of planting methods on leaf area index and photosynthetic performance of summer corn in saline-alkali soil

Changing planting patterns significantly increased leaf area index. Compared with Comparative Example 1, the leaf area index of Example 1, Comparative Example 2 and Comparative Example 3 during the spinning stage increased by 11.14%, 4.35% and 2.99% respectively, and the net photosynthetic rate increased by 18.88%, 12.72% and 5.58% respectively (Table 4).

Table 4 Effects of planting methods on leaf area index and net photosynthetic rate of summer corn in saline-alkali soil

2.5 Effects of planting methods on dry matter accumulation, grain yield and sorghum yield of summer corn in saline-alkali soil

By optimizing planting methods, the biomass of plants during the maturity stage and after silking can be significantly increased. Compared with Comparative Example 1 (T1), the total biomass of Example 1 (T4), Comparative Example 2 (T2), and Comparative Example 3 (T3) increased by 40.80%, 29.04%, and 17.14% (Figure 6). Compared with Comparative Example 1, the corn yields of Example 1, Comparative Example 2 and Comparative Example 3 significantly increased by 43.58%, 19.25% and 14.63%, the number of kernels per ear increased by 6.90%, 1.14% and 0.71% respectively, and the thousand-kernel weight increased by 25.06% respectively. , 13.63%, 10.84% (Table 5).

Table 5 Effects of planting methods on the yield and composition of summer corn and sorghum in saline-alkali soil

The above descriptions are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application shall be included in the protection scope of this application.

Claims (5)

1. A method for cultivating summer corn in mild to moderate saline-alkali soil, which is characterized by comprising the following steps: (1) Crush the wheat straw and spread it evenly on the cultivated land, spread the fertilizer, deep loosen and rotary till the soil, turn all the fertilizer into the soil, and then make ridges; the fertilizer includes humic acid compound fertilizer and microbial inoculant ; (2) Coat or dress summer corn seeds and sorghum seeds, sow summer corn seeds in furrows and sow sorghum seeds on ridges; (3) Field management is carried out after sowing, and summer corn and sorghum are harvested at the maturity stage respectively; In step (1), the ridge specifications are ridge height of 15 cm, ridge width of 40 cm, and furrow width of 20 cm; In step (1), the dosage of the humic acid compound fertilizer is 750 kg hm ^-2 , wherein N:P ₂ O ₅ :K ₂ O=26:10:12; the dosage of the microbial inoculant is 150 L hm ^-2 ; In step (1), the number of effective viable bacteria in the microbial agent is ≥3 billion/ml, fulvic acid ≥60g/L, organic matter ≥100g/L, N≥30g/L, P ₂ O ₅ ≥20g/L , K ₂ O≥10g/L, B≥2g/L; In step (2), when the summer corn variety is compact, the planting density is 60,000 plants hm ^-2 to 75,000 plants hm ^-2 ; when the summer corn variety is semi-compact, the planting density is 52,500 plants hm ^-2 ~ 60 000 plants hm ^-2 . 2. The cultivation method according to claim 1, characterized in that, in step (2), the summer corn seeds are summer corn seeds with a germination rate of ≥85% when the soil salt content is 0.3%; the sorghum Select seeds with short stalks and a growth period similar to the summer corn seeds. 3. The cultivation method according to claim 1, characterized in that, in step (3), herbicide is sprayed to seal the weeds after sowing and before emergence. 4. The cultivation method according to claim 1, characterized in that, in step (3), pesticides are sprayed during the large trumpet period to prevent diseases and insect pests. 5. The cultivation method according to claim 4, characterized in that, in step (3), the pesticide is 1000 times liquid of 10% difenoconazole water dispersible granules and 200 g L ^-1 chlorantraniliprole. Mix amide suspension agent 3000 times.