COMPARATIVE STUDY ON GROWTH AND YIELD RESPONSES OF FOUR SOYBEAN VARIETIES

Abstract

This field study was conducted to find out the phenology, growth and yield performances of soybean. Four soybean varieties viz. Bangladesh soybean-4, Sohag, BARI soybean-5 and BARI soybean-6 were used as study materials. The experiment was laid out in Randomized Complete Block Design with four replications at the research field of Crop Physiology and Ecology Department, HSTU, Dinajpur, Bangladesh. Results showed that phenology of four soybean varieties differed significantly from one another. The maximum days were required to attain vegetative and reproductive stages in the variety Bangladesh soybean-4 and the minimum days required to attain vegetative stage in the variety BARI soybean-S. In growing degree days (GDD) Bangladesh soybean-4 required statistically highest heat unit (GDD) to attain both the vegetative and reproductive stages, whereas BARI soybean-5 had the lowest GDD in both the vegetative and reproductive stages. Therefore, maximum heat use efficiency was found in the variety BARI soybean6 which was at par with BARI soybean-5 and Sohag whereas the minimum heat use efficiency was found in the variety of Bangladesh soybean-4 (In the present study, plant height, number of leaf and leaf area of all varieties started from a lower value and increased gradually with the advanced of the growth stage (DAS) and reached their peak at certain stage of growth). The highest plant height was observed in Bangladesh soybean-4 at 80 DAS. On the other hand the lowest plant height was observed in BARI soybean-5 at 80 DAS(The number of leaves plant 0 * and leaf area of four soybean varieties started from a lower value and increased gradually with the advanced of the growth stage (DAS) and reached their peak at certain stage of growth). The highest values of these parameters were observed in BARI soybean-6 at 80 DAS. On the other hand the lowest values of number of leaves and leaf area were observed in Bangladesh Soybean-4 at 80 DAS. Variations in total dry weight, leaf dry weight, pod dry weight, root dry weight, shoot length and root length among four soybean varieties were significant. Result showed that, the variety BARI soybean-6 showed highest values of these parameters, whereas the variety of Bangladesh soybean-4 showed lowest values. In yield and yield components viz. number of pods per plant, number of seeds per pod, 100- seed weight, seed yield per plant and grain yield (kg/ha) were highest with BARI Soybean-6, whereas Bangladesh Soybean-4 attained the lowest values of those important parameters. Finally, from the overall performances BARI soybean-6 may be considered as best variety among four tested varieties.