Genetic Variability and Inter-relationship of Kernel Carotenoids among Indigenous and Exotic Maize (Zea mays L.) Inbreds

Carotenoids play vital role in growth and development of human beings. Yellow maize kernel contains carotenoids that possess provitamin A and antioxidant activity. Multilocation based analyses of 105 maize inbreds of indigenous and exotic origin revealed wide genetic variation for lutein (0.2-11.3 mu g/g), zeaxanthin (0.2-20.0 mu g/g) and beta-carotene (0.0-15.0 mu g/g). For beta-cryptoxanthin, low variation (0.1-3.3 mu g/g) was observed. Carotenoids were quite stable over environments that played minor role in causing variation. The heritability (> 90%) and genetic advance (>75%) were high for all the carotenoid components. Zeaxanthin showed positive correlation with lutein and beta-cryptoxanthin, while beta-carotene, the major provitamin A carotenoid, did not show correlation with other carotenoids. Kernel colour was positively correlated with lutein (0.25), zeaxanthin (0.47) and beta-cryptoxanthin (0.44), but not with beta-carotene (0.04). This suggested that visual selection based on kernel colour will be misleading in selecting provitamin A-rich genotypes. Inbreds with provitamin A and non-provitamin A carotenoids identified in the present study will help in development of biofortified maize hybrids.