Performance of Biofortified Spring Wheat Genotypes for Grain Zinc and Iron Concentrations, Grain Yield and Associated Traits in Terai/plains of Nepal

Abstract

Breeding for nutrient-rich high yielding wheat varieties is one of the most economical and feasible ways to improve micronutrient deficiency ad hoc building better consumer health among the rural people of South Asia. To identify the Zinc (Zn) and Iron (Fe) enriched high yielding wheat genotypes, 7th Harvest Plus Yield Trial (7th HPYT) and 8th Harvest Plus Yield Trial (8th HPYT) both composed of 50 genotypes (including two CIMMYT checks " Kachu#1" and "Baj#1" and one Local Check "Gautam") were evaluated in alpha lattice design with 2 replications under timely sown irrigated condition at NWRP, Bhairahawa during 2016/17 and 2017/18. The grain Zn concentration and Fe concentration varies among genotypes from 23.8 to 42.4 ppm and 20.6 to 60.6 ppm, respectively. The highly significant positive correlation was found between grain zinc and iron concentration (r = 0.74** in 7th HPYT and r=0.67** in 8th HPYT). This highly positive significant relation between grain Zn and grain Fe indicates that it is feasible to simultaneously improve both micronutrients. In addition, this study reveals that thousand grains weight (TGW) has shown highly significant positive correlation (r = 0.3) with grain zinc and (r=0.4) with grain iron in 7th HPYT to non-significant negative correlation (r = -0.1) with grain zinc and (r=-0.1) with grain iron in 8th HPYT. As Nepali farmers major trait of interest second to grain yield is TGW, this showed that Zn and Fe enriched wheat varieties with higher TGW (bold grain) is feasible. The 9 genotypes in 7th HPYT and 48 genotypes in 8th HPYT showed higher grain yield than local check variety "GAUTAM" which indicates that bio-fortified genotypes are capable of producing higher grain yield with added micronutrient supplements in them. This study recommended 17 genotypes from the 7th HPYT and 38 genotypes from the 8thHPYT based on higher grain yield, grain Zn and Fe concentration and these lines were included in national yield trial for further evaluation in different agro-ecological domain of Nepal. The genotypes with higher grain Zn and Fe concentration viz., 7HPYT409, 7HPYT410, 8HPYT417, 8HPYT404 and 7HPYT442 could be used as donor parents in national wheat breeding program and high yielding genotypes 7HPYT448, 7HPYT418, 7HPYT426, 7HPYT413, 8HPYT415, 8HPYT431, 8HPYT429, 8HPYT407 and 8HPYT405 would be further evaluated throughout the Terai region of Nepal, and outstanding genotype could be recommended as variety for Terai/plains of Nepal.