Ratio of stable carbon and oxygen isotope discrimination ( Delta 13C/ Delta 18O) reflects variability in leaf intrinsic carboxylation efficiency in plants.

摘要

We describe a time-integrated approach based on stable isotope ratios of carbon and oxygen ( Delta 13C/ Delta 18O) to determine the variability in the mesophyll carbon assimilatory capacity of plants. Identifying crop genotypes with high mesophyll capacity for carbon assimilation has specific advantage in crop improvement, since such genotypes besides sustaining productivity under water-limited conditions can also save substantial amounts of irrigation water. We believe that this approach would provide a strong impetus to plant breeding efforts with assured success to improve productivity. The evaluation of the method using cowpea (APC-123-V683, APC 4125, V585, APC-121-P132 and APC 40-GC 20) and groundnut (NCAC-17090, VR1-4, ICGS-11 and SenNghean) genotypes is presented..