Variation in in vitro Morphogenic Response to Growth Regulators in Soybean Genotypes from India and Bulgaria

Soybean (Glycinae max (L.) Merrill.) is receiving great global importance due to its nutraceutical value but its cultivation suffers the problems of biotic/abiotic stress. To improve soybean germplasm biotechnological approach can be applied. The objectives of the experiments were to study the possibilities for establishment of in vitro cultures which can be used for genetic manipulations and modelling of stress. In vitro morphogeneic response of two Indian (Hardee and JS 335), one Bulgarian (Daniela) and one american (Hodson) soybean cultivars were studied using plant growth regulators. Using cotyledonary nodes as explants, high organogenic response was observed for cv Daniela and cv Hodson on media containig BAP and IBA. TDZ induced multiple shoot buds in all the cultivars, with varying degree of response and it was found to be genotype specific. A maximum of 8 shoot buds were obtained from cotyledonary node explants in presence of TDZ (0.5 mg/l) for the cv. Hardee. A negative correlation was observed between bud number and size for the Bulgarian cultivars. The results indicate the stimulating effect of TDZ on organogenesis and the interaction of genotype and culture media, which can be utilized for crop improvement using tissue culture techniques.