Large variability exits in phytase levels among Indian wheat varieties and synthetic hexaploids

Four hundred wheat genotypes including released varieties in India, advanced lines and synthetic hexaploids were used in the present investigation to assess the variability in phytase and phytate levels. Three different extraction processes such as direct, syringe and spin column methods were used for assessing phytase levels. The direct assay method showed greater potential for use in assaying enzyme activity in large numbers of samples over other methods and gave reproducible results (R2 = 0.87). The extraction and assay of the enzyme was faster and more cost effective compared to other methods. There were 3.4 fold variations in phytase levels among varieties and 5.9 fold among synthetic hexaploids. In contrast, lower variability (1.6 fold in varieties and 2.2 fold in synthetic hexaploids) was observed in phytate levels. Ten varieties grown in 4 locations in India were used to assess the genotypic and environmental effect on phytase and phytate levels. There were significant effects of both genotype and environment on phytate and phytase levels; it was more genetic with heritability of 0.98 and 0.82 for phytase and phytate, respectively. Higher variability in phytase levels and more genotypic effect on the enzyme activity demonstrated the potential of improving phytase levels through breeding.