Determination and inheritance of phytic acid as marker in diverse genetic group of bread wheat

Abstract

Phytic acid (Myo-inositol 1,2,3,4,5,6 hexa-kisphophate) is a storage form of phosphorus and can accumulate to the levels as high as 35% in the wheat kernel. Phytic acid acts as an inhibitor for macronutrients as well as micronutrients and located in the bran of wheat kernel. Due to its inhibitory role, a high con-centration of phytic acid is undesirable as it hinders the bio-availability of some essential nutrients such as Fe, Mg, Ca, Zn and Cu, etc. In order to check the in-heritance of phytic acid in wheat kernels, phytic acid concentration was initially determined in kernels of 10 wheat genotypes to identify two contrasting genetic groups for diallel analysis. Based on pre-screening results of 10 wheat genotypes, five wheat genotypes (3 with high and 2 with low phytic acid concentration) were crossed in all possible combinations during 2007-2008 by 5 × 5 full diallel mating fashion to in-sight the inheritance of phytic acid and other yield contributing traits. All 20 F 1 hybrids and five paren-tal genotypes revealed significant differences statisti-cally, except plant maturity. The narrow and broad sense heritability estimates varied widely among traits for spike length (0.17, 0.62), spikelets spike −1 (0.35, 0.74), tillers plant −1 (0.05, 0.52) and phytic acid con-centration (0.01, 0.86). The values for phytic acid con-centration ranged from 0.56% to 3.43% among F 1 hybrids and 1.06 to 3.67% for parental genotypes. F 1 hybrids, Ps-2005 × Ghaznavi (0.56%), AUP-4006 × Ps-2004 (0.74%), Janbaz × Ps-2004 (0.89%) and Jan-baz × Ps-2005 (1.01%), had the lowest concentration of phytic acid. The study concluded that F 1 hybrids with low phytic acid concentration could yield desir-able segregants.