Mixed model-based indices for selection of sweet potato genotypes for different agronomic aptitudes

Abstract

The objective of this study was to identify the aptitude of sweet potato genotypes derived from botanical seeds and select them for the aptitudes human consumption, ethanol production, and animal feed through separate indices. A row–column incomplete block design was used, restricting relatedness in the draw. A total of 1604 half-sib genotypes resulting from recombination of 55 clones from the germplasm collection of the Federal University of Lavras were evaluated. The accessions UFVJM 58 and UFVJM 61 were used as controls, for a total of 1606 treatments. The aptitude indices corresponded to the mean values of the 10 traits evaluated, with weights assigned to each trait according to the aptitude of interest. The data of all three aptitudes were transformed and standardized. Then, using the Zi index and with 2.5% selection pressure, the most promising genotypes were selected through the best linear unbiased predictor according to the traits evaluated and the aptitude of interest. Sixty genotypes were selected (out of 1604 tested) based on one or more of the three reported aptitudes: 25 showed a single aptitude, whereas 20 showed dual aptitude and 15 showed triple. The data obtained will provide information for breeding programmes of the sweet potato crop. There is great genetic variability for the traits evaluated, facilitating the selection of new genotypes, with the possibility of obtaining new cultivars important for national food sovereignty and making a significant social contribution.