Establishment of gene pools for systematic heterosis exploitation in sugarcane breeding

Thiago Otavio Mendes de Paula; Bruno Portela Brasileiro; Danilo Eduardo Cursi; Edjane Gonçalves de Freitas; João Messias dos Santos; Marcos Deon Vilela de Resende; Collins Kimbeng; Márcio Henrique Pereira Barbosa

In sugarcane (Saccharum spp) breeding, despite the potential use of reciprocal recurrent selection (RRS) to explore both non‐additive and additive effects for economic value traits, to date no publications have targeted obtaining heterotic groups to support this selection strategy. The aim of this study was: i) to identify sugarcane gene pools to effectively explore non‐additive and additive genetic effects via reciprocal recurrent selection, ii) to estimate genetic parameters and iii) to select parents and cross combinations. Seventy‐nine sugarcane families obtained from crossing 38 parents in a crossing scheme known as disconnected factorial design were evaluated. The families were divided into three field trials and established in a randomized complete‐block design with five replicates. The statistical genetic analysis was performed with linear mixed models through REML/BLUP. The results revealed that non‐additive effects were predominant in explaining genetic variation for cane yield (TCH; t/ha), pol yield (TPH; t/ha) and fiber yield (TFH; t/ha). For brix, fiber and corrected Pol (PCC) traits, additive effects were predominant. Estimates of specific combining ability (SCA) and pedigree information allowed the establishment of gene pools for systematic heterosis exploitation through reciprocal recurrent selection breeding efforts. The prediction of the additive genetic values of parents for selection based on the progeny's behavior obtained via disconnected factorial design is an alternative that should be used in sugarcane breeding programs.