IRON-ZINC BASED GENETIC DIVERSITY ASSESSMENT IN MAIZE (ZEA MAYS L.) GENOTYPES

Abstract

Hidden hunger is one of the most important challenges of the current era, and genetic biofortification is the most feasible, cheapest, and sustainable way to provide a balanced diet to the community. Given the value of biofortification in food grains, the relevant study sought to screen maize inbred lines for kernel Fe and Zn contents and estimate their bioavailability using molar ratios. One hundred maize inbred lines planted during spring 2018 in soil contained optimal levels of Fe and Zn. Maize genotypes evaluation comprised plant height, days to tasseling, silking, maturity, cob length, number of rows per cob, grains per row, grains per cob, 100-grain weight, grain yield per plant, grain Fe, Zn, and phytic acid contents. Significant differences emerged for all the studied traits. The results of the correlation study indicated that grain Fe and Zn contents had a positive genetic link with each other while a non-significant negative association with phytic acid and grain yield. A substantial positive correlation of grain yield occurred with rows per cob, grains per row, and grains per cob. Cluster and principal component analyses ran through, with PA/Fe and PA/Zn molar ratios calculated to estimate the mineral bioavailability. Based on the genetic variability for grain yield, Fe, Zn, and PA contents, four clusters resulted, and the first two PCs had an eigenvalue of more than one and depicted 76.91% of the total variance. Genotypes M-11, M-41, M-45, M-56, M-60, M-61, M-66, M-80, M-96, and M-98 showed high Fe and Zn contents with low molar ratios and are potential to benefit further breeding programs to develop biofortified maize hybrids.