Estimating breeding values of genotypes for sugarcane yield using data from unselected progeny populations

Abstract

Breeding value refers to the ability of a genotype to produce superior progenies when crossed with other genotypes and are used to predict the performance of a genotype as a parent in plant and animal breeding. The objectives of this study were to estimate the breeding values of genotypes for cane yield, to determine the proportions of elite female and male parents, and evaluate their implications for sugarcane breeding. Families produced from crossing were planted in field trials using a randomised complete block design with three replications across seven regional breeding programmes from 2010 to 2015. From the first 20 progenies per plot, cane yield was estimated from stalk number, stalk height and stalk diameter that were subjected to best linear unbiased prediction analysis. Significant (P < 0.05) female and male variances indicated that the large variability observed among progenies could be attributed to the variability among genotypes used for crossing. Genotypes 82H0397, 85H0428, N52, B74713, 87W0629, 01G1662, 88W1323, 02K1657, 87L0573, 97E0474, N31, 93E0888, 03U1030, 06T3608, 96W0246, WI82498 and 79F0779, with high breeding values, produced progenies with high cane yield when crossed with diverse parents, which indicated broad general combining ability. The proportions of genotypes with high breeding values were higher for the coastal short cycle high potential (29.4%), coastal long cycle high potential (28.0%), humic soil (27.8%) and irrigated (26.0%) populations compared to the sandy soil (22.9%), coastal short cycle average potential (21.0%) and coastal long cycle average potential (18.4%) populations, probably due to longer cycles of recurrent breeding and selection. Low numbers of genotypes with high breeding values suggested that intensive evaluation and development of genotypes, used for crossing, are required in these populations.