Changes in endogenous gibberellic acid (GA) levels were determined in developing seeds and pods of pigeon pea (Cajanus cajan). Antibodies against GA3 were raised in rabbits and indirect ELISA developed to estimate GA level. Two varieties, black seeded variety (V1) and B.D.N2 (V2), were selected on the basis of their seed index value. The pod length and number of seeds per pod were significantly different for the two varieties. Dry weight, water content (WC), rate of water accumulation, rate of dry matter accumulation (DMA), and GA content in pod and seed were all larger in V1 than in V2. In both varieties, higher GA content was observed during cell elongation and DMA phases, respective to their varietal differences in growth traits. Relationships between WC and rate of DMA, and WC and GA differed significantly between the two varieties. The results suggest a role of GA and WC in sink-size development in both varieties studied.
Cajanus cajan; dry matter accumulation; endogenous gibberellic acid; seed development; water content
