Prospects of breeding for micronutrients and b-carotene-dense sorghums

Eighty-four sorghum lines, produced from parental lines of popular hybrids, cultivars, yellow endosperm lines, germplasm lines, lines characterized by high protein digestibility, lines with high lysine contents and waxy lines, were evaluated in Patancheru, Andhra Pradesh, India, during the post-rainy season of 2003-04. Significant genetic differences for Fe, Zn and phytate contents, and agronomic and grain traits were observed. The grain Fe content ranged from 20.1 (ICSR 93031) to 37.0 ppm (ICSB 472 and 296 B), whereas the Zn content varied from 13.4 (JJ 1041) to 31.0 ppm (IS 11990). Zn and Fe contents, which showed substantial heritability, were significantly and positively correlated. Stover and grain yields were weakly and negatively correlated with grain Fe content, but were strongly and negatively correlated with the grain Zn content. The number of days to 50% flowering and plant height were weakly correlated with grain Fe and Zn contents. Grain luster was positively correlated with grain Fe content, but was weakly correlated with grain Zn content. The grains of non-yellow endosperm lines had trace amounts of ?-carotene. In 11 yellow endosperm lines, the grain ?-carotene content ranged from 0.56 (IS 24724) to 1.132 ppm (IS 26886), with 6 lines (IS 7684, IS 7776, IS 24703, IS 24868, IS 24883 and IS 26886) having higher ?-carotene contents than the average of 0.85 ppm. The ?-carotene content was poorly correlated with grain Fe and Zn contents. The grain phytate content, characterized by a slight variation between phenotypic and genetic coefficients of variation and high heritability, was weakly correlated with grain Fe and Zn contents

B V S Reddy, S Ramesh, T Longvah, 'Prospects of breeding for micronutrients and b-carotene-dense sorghums', International Sorghum and Millets Newsletter, vol. 46, pp.10-14, 2011