Analysis of sugarcane × Saccharum spontaneum progeny for sugar and biomass traits

Abstract

AbstractSugarcane production benefitted from useful genes imparted from Saccharum spontaneum L. Interspecific hybrids were evaluated for sugar and biomass traits in three environments, including two plants and one ratoon crop. The objective was to estimate genetic parameters for traits in this population and to develop appropriate breeding strategies and germplasm for use in variety development in both the sugar and bioenergy industries. Heritability was highest with all three environments considered; however, the increase was minimal compared with estimates from the first ratoon crop, suggesting resources will be better spent selecting in the first ratoon crop. Significant differences (p < 0.05) found among families for sucrose content‐related traits warrant selecting first among families before selecting among genotypes within families for these traits. The same was not true for cane yield and its components. Heritability was low to moderate (> 0.3 < 0.47) for cane yield and its components and high (> 0.7) for all other traits, suggesting early selection in small plots could emphasize sucrose content‐related traits. Selecting intensely for a highly heritable trait in one stage can influence genetic variation of another trait in subsequent stages. Therefore, multivariate selection methods were employed that identified groups of genotypes with characteristics distinct to both industries. The S. spontaneum parents dominated trait variation in the hybrid population. Consequently, although genotypes with potential for the sugar industry would have to undergo rounds of backcrossing to recover good sugar characteristics, genotypes with immediate potential in the bioenergy industry were easily identified in this population.