Genetic diversity and heritability of chlorophyll content and photosynthetic indexes among some Iranian wheat genotypes

Genetic diversity and heritability of Chlorophyll (Chl) content and some photosynthetic indexes were studied in thirty wheat genotypes through randomized complete block design with three replications at 2009. The maximum and minimum heritability were obtained for chlorophyll (0.75-0.89) and stomatal conductance (0.2), respectively. The least phenotypic and genotypic coefficients of variation were observed for CO2 levels in boundary layer. Phenotypic and genotypic correlation coefficients between Chl a, Chl b and total Chl were similar and between SPAD Chl and Chl b were significantly high. Chl b content and transpiration rate, stomatal conductance and H2O levels in boundary layer had positive and significant genotypic correlation. CO2 levels in boundary layer and stomatal conductance were significantly and linearly associated with photosynthesis rate. 78.62% of data variation was explained by two factors. Genotypes in first group showed appropriate photosynthetic characters for resistance to drought and heat. Genotypes in third group have high chlorophyll content and photosynthesis rate. Maximum (103.19) and minimum (0.98) genetic distance was found between Moghan 3 and Kavir and between star and Tajan, respectively.