Regulatory effect of ethyl-methane-sulfonate on chlorophyll metabolism in Triticum aestivum L.

The regulatory effect of EMS on chlorophyll metabolism was studied in two hexaploid wheat genotypes. Presoaked seeds were treated with EMS 0.2%, 0.4% and 0.6% at 3½ hr., 7 hr. and 9 hr. durations respectively. Leaf extracts from treated as well as from control plant were compared spectrophotometrically to determine Chl. a, Chl. b and total chlorophyll contents, and its relationship to grain weight was established, using plants grown in pot conditions. Total chlorophyll content of treated plants demonstrated significant increase over their parents (control). Maximum increase (93.87%) in toatl chlorophyll content was recorded in variety Al-Samma at EMS 0.4% with 7 hr. duration, with subsequent increase of 35.89% in seed weight, indicating this treatment can effectively be exploited to evolve mutants with enhanced chlorophyll metabolism.Chlorophyll content was correlated to 100-seed weight on plant basis. Significant positive relationship between chlorophyll content and seed weight was detected in most of the EMS treatments. The improvement of genotypes with high chlorophyll content might result in the improvent of photosynthesis in wheat plants leading to the improvement of grain yield.