The purpose of the study was to determine the farmers' perceptions of management measures aga... more The purpose of the study was to determine the farmers' perceptions of management measures against insect and disease pests and the profitability of five winter vegetables grown in Bangladesh's Sirajganj area. The highest incidences of fungal infections, including curd rot of cauliflower and early blight of tomato, were discovered. One of the most destructive diseases of brinjal and tomato was wilt, which was caused by both fungi and bacteria. Farmers took the necessary steps to control aphids (40-150 insects m–2 or 20-50 infected shoots m–2), brinjal shoot and fruit borer (10-50 insects 10m–2 or 20-60 infected shoots or fruits 10m–2), and other insects at the threshold level. They employed physical, chemical, and Integrated Pest Management (IPM) techniques to manage the disease and insect pests. The greatest amount of insecticide spraying (35-45 times) was performed to control brinjal shoot and fruit borer insects. The entire manufacturing cost followed the pattern tomato &g...
Bangladesh Journal of Scientific and Industrial Research, 2020
Based on the 36 quantitative morphological descriptors, agglomerative hierarchical clustering (AH... more Based on the 36 quantitative morphological descriptors, agglomerative hierarchical clustering (AHC) and principal component analyses (PCA) were conducted to identify 106 diverse Sesbania accessions. The AHC analysis identified three major clusters with 11 sub-clusters. In PCA, the first and second PCs explain 72.48% and 12.72% of total variations with high Eigen value 9.1 and 1.7, respectively. Sesbania accessions occupied four distinct positions in the PCA graph. Based on multivariate analyses and qualitative descriptors, Sesbania accessions have been identified as S. bispinosa (90 accessions), S. cannabina (9 accessions), S. sesban (6 accessions) and the known S. rostrata. The AHC dendrogram has detected the close similarities between S. rostrata and S. cannabina. However, the PCA has emerged to be better than the AHC as a species identification tool. Among these four species, the highest discriminating distance (23.69%) was observed between S. sesban and S. bispinosa, and the low...
The need for a characterization of germfree life in some detail can be justified in different way... more The need for a characterization of germfree life in some detail can be justified in different ways. First, now that germfree animals have been reared for generations and on a larger scale, we need current information about the general characteristics of the germfree stock. More specifically, we must ask ourselves whether various germfree species, as they are available today, truly represent the standardized biological tool of our long-standing anticipation. A second reason, stressing the need for descriptive work on the germfree animal, concerns its broad use in the field of experimentation. The germfree host, differing from normal stock not only by its absence of the bacterial flora but also by its lack of systemic responses to that flora, is an animal that is considerably different from the conventional one. The average worker who wishes to use the germfree tool occasionally cannot possibly gauge for himself the details of this broader background, yet it is clear that these details will affect his results. Therefore, it appears that there is need for the elaboration of a limited but comprehensive parameter in this field. A third justification for descriptive work in the germfree animal concerns the environmental physiologist. A study of the germfree host in comparison to the normal stock, including animals exposed to controlled bacterial contamination, portrays the effects of the normal flora on the animal with great clarity. Finally, there is genuine appeal in the exploration of this largely unknown form of life. In view of these considerations, the questions raised in this presentation may be defined as: (1) What are the conspicuous characteristics of the germfree animal as it is reared today in comparison to the normal stock? (2) Are these characteristics indeed caused by the lack of bacterial stimulation, or can it be conjectured that they are the result of other, accidentally introduced) nonbacterial variables) such as the highly artificial environment or diets? Before taking up the results of our work, a brief review of the history of this problem is needed. The origin of this discipline is unusual in that the man who conceived it thought that its essence, normal germfree life, was not possible. Pasteur,' formulated in 1885 what he himself called a preconceived idea, that life would become probably impossible in animals deprived of their normal flora. In saying this, it was pointed out by some of his contemporaries, Pasteur expressed his belief in the principle of the survival of the fittest. The normal bacterium-haboring animal in nature must necessarily represent some form of * The work reported in this paper was supported in part by Contract NR 131-067 between the Office of Naval Research, Department of the Navy, Washington, D. C., and the University of Notre Dame.
Research in Agriculture Livestock and Fisheries, 2022
Plant spacing ensures uniform and optimum plant population and facilitates sufficient natural res... more Plant spacing ensures uniform and optimum plant population and facilitates sufficient natural resources for crop growth which, in turns influences the crop yield positively. An investigation was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University, during July to December 2017 to study the influence of plant spacing on the yield of double grained rice cultivar. The study comprised five spacing viz. 25 cm × 15 cm, 25 cm × 10 cm, 20 cm × 15 cm, 20 cm × 10 cm and 15 cm × 15 cm and two rice cultivars viz. a double grained rice cultivar and BRRI dhan49 and a double grained rice cultivar. It was laid out in a randomized complete block design with three replications. The double grained rice cultivar produced taller plant (155.65 cm), longer panicle (23.93 cm), higher 1000-grain weight (25.96) and higher straw yield (6.90 t ha-1), though the higher grain yield (3.68 t ha-1) was found in the test cultivar (BRRI dhan49). Planting at 20 cm × 15 cm produced the highest...
An experiment was conducted at the Field Laboratory, Department of Crop Botany, Bangladesh Agricu... more An experiment was conducted at the Field Laboratory, Department of Crop Botany, Bangladesh Agricultural University during Aman season 2018 primarily to describe agro-morphological descriptors of a purple rice cultivar and to evaluate the effect of spacing on morphological traits, yield contributing characters and yield. The experiment comprised four rice cultivars; Purple rice and three other check cultivars viz. BR22, BRRI dhan34 and BRRI dhan46, and three spacing viz. 15 cm× 15 cm, 20 cm× 15 cm and 25 cm× 15 cm. The experiment was laid out in randomized complete block design with three replications. All the studied morphological traits, yield contributing characters and yield were significantly differed among the cultivars and planting densities. Purple rice cultivar was 101.8 cm in height; the number of total tillers hill−1 12.88, number of non-effective tiller hill−1 1.37; leaf vertical and straight, purple in colour; panicle length 23.63 cm, number of primary and secondary bran...
Seed and seedling morphology of 110 dhaincha accessions were studied to search new characters tha... more Seed and seedling morphology of 110 dhaincha accessions were studied to search new characters that could add information pertinent to their species identification. Four seed coat colours red, brown, grey and black, and two seed shapes cylindrical and rectangular, were observed. Grey coloured, rectangular seeds produced seedlings with swollen radical with violet coloured hypocotyls. Wide variations were observed in the values of other morphological descriptors. Agglomerative hierarchical cluster analysis using quantitative descriptors showed that 110 accessions clustered in to four groups. The first two components (Factor 1 and 2) of principal component analysis explained 62.01% of the total variance of the collected dhaincha accessions. Seedlings with swollen radical and violet coloured hypocotyls, produced from grey coloured and rectangular seeds, were constantly positioned together in a cluster. Seed coat colour, shape of seed and radical, and hypocotyls colour may be used as impo...
An experiment was conducted at Field and Plant Systematics Laboratories of the Department of Crop... more An experiment was conducted at Field and Plant Systematics Laboratories of the Department of Crop Botany, Bangladesh Agricultural University, Mymensingh, to study the phenology and to search for new descriptors from reproductive morphology for convenient field identification of Sesbania species. Seeds of one hundred and five accessions from three Sesbania species viz. S. bispinosa, S. cannabina and S. sesban, were collected and used as experimental materials. Seeds were sown at the spacing 50 cm (row–row) × 15 cm (plant–plant). Ratoon, the regrowth of shoot from previous year’s harvest, was observed only in S. sesban and also used as experimental material. Results revealed that the days required for 50% inflorescence bearing, flower & pod initiation and pod maturation were higher in S. sesban ratoon and lowest in S. sesban; S. sesban ratoon also produces the largest flowers and the smallest in S. bispinosa. Pollen grains are monad, tricolporate, prolate and exine sculpture reticulat...
The effect of regional diversity on 12 agro-morphological descriptors of Sesbania bispinosa (Jacq... more The effect of regional diversity on 12 agro-morphological descriptors of Sesbania bispinosa (Jacq.) W. Wight was studied. The mean sum of square varied significantly for six of these traits viz., plant height, branch number/plant, pod number/plant, pod length, seed number/pod and seed width. Among the ten regions, plants grown from seeds of Tangail, Chuadanga and Sirajganj districts of Bangladesh performed better in terms of plant height, number of branches/plant, number of pods/plant, pod length, number of seeds/pod and seed width. In principal component analysis, first six principal components (PC1, PC2, PC3, PC4, PC5 and PC6) showed Eigen value >1 and accounted for 85.6% of the total variance. In cluster analysis based on the studied agro-morphological descriptors, the cluster 1 consists of three regions (Chuadanga, Tangail and Jhinaidah), cluster 2 of six regions (Khulna, Mymensingh, Rangpur, Sunamganj, Gaibandha and Faridpur) and cluster 3 of only one district (Sirajganj). C...
An experiment was carried out at Plant Systematics Laboratory of the Department of Crop Botany, B... more An experiment was carried out at Plant Systematics Laboratory of the Department of Crop Botany, Bangladesh Agricultural University, Mymensingh to find out the effect of seed size on germination and seedling growth of three Sesbania species. Seed size was graded as small (3.1–3.5 mm), medium (3.6–4.0 mm) and large (4.1–4.5 mm); and three Sesbania species viz. S. bispinosa, S. cannabina and S. sesban, were used as experimental materials. The treatments were arranged in factorial experiment laid in completely randomized design having four replications. Though the effect of seed size on germination and seedling growth parameters followed similar trend, significant differences were observed among these three Sesbania species. Medium-sized seed produced the highest percentage of emergence and germination, and large-sized seed produced the highest seedling length, vigour index, and total biomass; although the numerical values did not differ statistically. The small-sized seeds were poor pe...
The purpose of the study was to determine the farmers' perceptions of management measures aga... more The purpose of the study was to determine the farmers' perceptions of management measures against insect and disease pests and the profitability of five winter vegetables grown in Bangladesh's Sirajganj area. The highest incidences of fungal infections, including curd rot of cauliflower and early blight of tomato, were discovered. One of the most destructive diseases of brinjal and tomato was wilt, which was caused by both fungi and bacteria. Farmers took the necessary steps to control aphids (40-150 insects m–2 or 20-50 infected shoots m–2), brinjal shoot and fruit borer (10-50 insects 10m–2 or 20-60 infected shoots or fruits 10m–2), and other insects at the threshold level. They employed physical, chemical, and Integrated Pest Management (IPM) techniques to manage the disease and insect pests. The greatest amount of insecticide spraying (35-45 times) was performed to control brinjal shoot and fruit borer insects. The entire manufacturing cost followed the pattern tomato &g...
Bangladesh Journal of Scientific and Industrial Research, 2020
Based on the 36 quantitative morphological descriptors, agglomerative hierarchical clustering (AH... more Based on the 36 quantitative morphological descriptors, agglomerative hierarchical clustering (AHC) and principal component analyses (PCA) were conducted to identify 106 diverse Sesbania accessions. The AHC analysis identified three major clusters with 11 sub-clusters. In PCA, the first and second PCs explain 72.48% and 12.72% of total variations with high Eigen value 9.1 and 1.7, respectively. Sesbania accessions occupied four distinct positions in the PCA graph. Based on multivariate analyses and qualitative descriptors, Sesbania accessions have been identified as S. bispinosa (90 accessions), S. cannabina (9 accessions), S. sesban (6 accessions) and the known S. rostrata. The AHC dendrogram has detected the close similarities between S. rostrata and S. cannabina. However, the PCA has emerged to be better than the AHC as a species identification tool. Among these four species, the highest discriminating distance (23.69%) was observed between S. sesban and S. bispinosa, and the low...
The need for a characterization of germfree life in some detail can be justified in different way... more The need for a characterization of germfree life in some detail can be justified in different ways. First, now that germfree animals have been reared for generations and on a larger scale, we need current information about the general characteristics of the germfree stock. More specifically, we must ask ourselves whether various germfree species, as they are available today, truly represent the standardized biological tool of our long-standing anticipation. A second reason, stressing the need for descriptive work on the germfree animal, concerns its broad use in the field of experimentation. The germfree host, differing from normal stock not only by its absence of the bacterial flora but also by its lack of systemic responses to that flora, is an animal that is considerably different from the conventional one. The average worker who wishes to use the germfree tool occasionally cannot possibly gauge for himself the details of this broader background, yet it is clear that these details will affect his results. Therefore, it appears that there is need for the elaboration of a limited but comprehensive parameter in this field. A third justification for descriptive work in the germfree animal concerns the environmental physiologist. A study of the germfree host in comparison to the normal stock, including animals exposed to controlled bacterial contamination, portrays the effects of the normal flora on the animal with great clarity. Finally, there is genuine appeal in the exploration of this largely unknown form of life. In view of these considerations, the questions raised in this presentation may be defined as: (1) What are the conspicuous characteristics of the germfree animal as it is reared today in comparison to the normal stock? (2) Are these characteristics indeed caused by the lack of bacterial stimulation, or can it be conjectured that they are the result of other, accidentally introduced) nonbacterial variables) such as the highly artificial environment or diets? Before taking up the results of our work, a brief review of the history of this problem is needed. The origin of this discipline is unusual in that the man who conceived it thought that its essence, normal germfree life, was not possible. Pasteur,' formulated in 1885 what he himself called a preconceived idea, that life would become probably impossible in animals deprived of their normal flora. In saying this, it was pointed out by some of his contemporaries, Pasteur expressed his belief in the principle of the survival of the fittest. The normal bacterium-haboring animal in nature must necessarily represent some form of * The work reported in this paper was supported in part by Contract NR 131-067 between the Office of Naval Research, Department of the Navy, Washington, D. C., and the University of Notre Dame.
Research in Agriculture Livestock and Fisheries, 2022
Plant spacing ensures uniform and optimum plant population and facilitates sufficient natural res... more Plant spacing ensures uniform and optimum plant population and facilitates sufficient natural resources for crop growth which, in turns influences the crop yield positively. An investigation was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University, during July to December 2017 to study the influence of plant spacing on the yield of double grained rice cultivar. The study comprised five spacing viz. 25 cm × 15 cm, 25 cm × 10 cm, 20 cm × 15 cm, 20 cm × 10 cm and 15 cm × 15 cm and two rice cultivars viz. a double grained rice cultivar and BRRI dhan49 and a double grained rice cultivar. It was laid out in a randomized complete block design with three replications. The double grained rice cultivar produced taller plant (155.65 cm), longer panicle (23.93 cm), higher 1000-grain weight (25.96) and higher straw yield (6.90 t ha-1), though the higher grain yield (3.68 t ha-1) was found in the test cultivar (BRRI dhan49). Planting at 20 cm × 15 cm produced the highest...
An experiment was conducted at the Field Laboratory, Department of Crop Botany, Bangladesh Agricu... more An experiment was conducted at the Field Laboratory, Department of Crop Botany, Bangladesh Agricultural University during Aman season 2018 primarily to describe agro-morphological descriptors of a purple rice cultivar and to evaluate the effect of spacing on morphological traits, yield contributing characters and yield. The experiment comprised four rice cultivars; Purple rice and three other check cultivars viz. BR22, BRRI dhan34 and BRRI dhan46, and three spacing viz. 15 cm× 15 cm, 20 cm× 15 cm and 25 cm× 15 cm. The experiment was laid out in randomized complete block design with three replications. All the studied morphological traits, yield contributing characters and yield were significantly differed among the cultivars and planting densities. Purple rice cultivar was 101.8 cm in height; the number of total tillers hill−1 12.88, number of non-effective tiller hill−1 1.37; leaf vertical and straight, purple in colour; panicle length 23.63 cm, number of primary and secondary bran...
Seed and seedling morphology of 110 dhaincha accessions were studied to search new characters tha... more Seed and seedling morphology of 110 dhaincha accessions were studied to search new characters that could add information pertinent to their species identification. Four seed coat colours red, brown, grey and black, and two seed shapes cylindrical and rectangular, were observed. Grey coloured, rectangular seeds produced seedlings with swollen radical with violet coloured hypocotyls. Wide variations were observed in the values of other morphological descriptors. Agglomerative hierarchical cluster analysis using quantitative descriptors showed that 110 accessions clustered in to four groups. The first two components (Factor 1 and 2) of principal component analysis explained 62.01% of the total variance of the collected dhaincha accessions. Seedlings with swollen radical and violet coloured hypocotyls, produced from grey coloured and rectangular seeds, were constantly positioned together in a cluster. Seed coat colour, shape of seed and radical, and hypocotyls colour may be used as impo...
An experiment was conducted at Field and Plant Systematics Laboratories of the Department of Crop... more An experiment was conducted at Field and Plant Systematics Laboratories of the Department of Crop Botany, Bangladesh Agricultural University, Mymensingh, to study the phenology and to search for new descriptors from reproductive morphology for convenient field identification of Sesbania species. Seeds of one hundred and five accessions from three Sesbania species viz. S. bispinosa, S. cannabina and S. sesban, were collected and used as experimental materials. Seeds were sown at the spacing 50 cm (row–row) × 15 cm (plant–plant). Ratoon, the regrowth of shoot from previous year’s harvest, was observed only in S. sesban and also used as experimental material. Results revealed that the days required for 50% inflorescence bearing, flower & pod initiation and pod maturation were higher in S. sesban ratoon and lowest in S. sesban; S. sesban ratoon also produces the largest flowers and the smallest in S. bispinosa. Pollen grains are monad, tricolporate, prolate and exine sculpture reticulat...
The effect of regional diversity on 12 agro-morphological descriptors of Sesbania bispinosa (Jacq... more The effect of regional diversity on 12 agro-morphological descriptors of Sesbania bispinosa (Jacq.) W. Wight was studied. The mean sum of square varied significantly for six of these traits viz., plant height, branch number/plant, pod number/plant, pod length, seed number/pod and seed width. Among the ten regions, plants grown from seeds of Tangail, Chuadanga and Sirajganj districts of Bangladesh performed better in terms of plant height, number of branches/plant, number of pods/plant, pod length, number of seeds/pod and seed width. In principal component analysis, first six principal components (PC1, PC2, PC3, PC4, PC5 and PC6) showed Eigen value >1 and accounted for 85.6% of the total variance. In cluster analysis based on the studied agro-morphological descriptors, the cluster 1 consists of three regions (Chuadanga, Tangail and Jhinaidah), cluster 2 of six regions (Khulna, Mymensingh, Rangpur, Sunamganj, Gaibandha and Faridpur) and cluster 3 of only one district (Sirajganj). C...
An experiment was carried out at Plant Systematics Laboratory of the Department of Crop Botany, B... more An experiment was carried out at Plant Systematics Laboratory of the Department of Crop Botany, Bangladesh Agricultural University, Mymensingh to find out the effect of seed size on germination and seedling growth of three Sesbania species. Seed size was graded as small (3.1–3.5 mm), medium (3.6–4.0 mm) and large (4.1–4.5 mm); and three Sesbania species viz. S. bispinosa, S. cannabina and S. sesban, were used as experimental materials. The treatments were arranged in factorial experiment laid in completely randomized design having four replications. Though the effect of seed size on germination and seedling growth parameters followed similar trend, significant differences were observed among these three Sesbania species. Medium-sized seed produced the highest percentage of emergence and germination, and large-sized seed produced the highest seedling length, vigour index, and total biomass; although the numerical values did not differ statistically. The small-sized seeds were poor pe...
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