Recurrent selection method for improvement of lutein and zeaxanthin in orange waxy corn populations

The information on the responses to simple recurrent selection for yield and total carotenoid content in orange waxy corn is lacking. The objectives were to evaluate the responses to simple recurrent selection for two cycles for yield and carotenoids of orange waxy corn population and to investigate the correlations between color parameter with carotenoids in waxy corn kernels. Parental sources of germplasm with differences in kernel colors and levels of disease resistance were used for generation of a base population of orange waxy corn. A simple recurrent selection for superior phenotypes was practiced on this population for two selection cycles. Cycle 0 (C0), C1 and C2 were evaluated for two locations in 2016. The cycles showed significant differences for most traits except for plant height. The locations contributed to large portions of total variation in total yield, whereas selection cycle contributed to large portions of total variations in lutein, zeaxanthin, β-carotene and total carotenoid content and color parameter (ho), indicating that selection for carotenoids would be possible. Simple recurrent selection for two cycles increased total yield and husked ear weight of 23.2% and 15.0%, respectively. Simple recurrent selection for two cycles also increased lutein, zeaxanthin, β-carotene and total carotenoid content with increasing percentages ranging from 18.5 to 196.6%. The results indicated that population improvement by simple recurrent selection could be useful in increasing these traits. Color parameter at immature stage and dry stage was negatively and significantly correlated with lutein, zeaxanthin, β-carotene and total carotenoid content, indicating that color parameter can be used as an indirect selection criterion for these traits.