Department of Botany, Punjab University, Chandigarh - 160 014, India.
Experiments were conducted to study the nodular metabolism, in order to draw comparisons between nitrogen fixation, carbon fixation and ammonia assimilation in nodule cytosol of desi (CSG 8962, DCP 92-3) and kabuli (CSG 9651, BG 267) genotypes of chickpea. Maximum acetylene reduction activity (ARA) was observed in CSG 9651 and minimum in DCP 92-3.The specific activity of ammonia assimilating enzymes GS, GDH, GOGAT was less affected in the CSG 9651, CSG 8962 as compared to BG 267, DCP 92-3. GS activity was more tolerant of salinity than GOGAT and it limits ammonia assimilation under saline stress. Nodule phosphoenol pyruvate carboxylase (PEPC) activity wasenhanced by salt stress and was clearly related to salt concentration. Chickpea genotypes tolerant to salt stress have better enzyme activities responsible for higher nodule nitrogen fixation.
