Genotypic divergence between sugarcane genotypes

Abstract

The aim of this study was to evaluate the genetic divergence between seven standard-varieties and eleven RB (República do Brasil) sugarcane clones, by uni and multivariate techniques, based in ten agroindustrial characters. The experiment was developed in the agricultural area of Trapiche Sugar Mill – Sirinhaém, Pernambuco, Brazil, in the crop year 2005/2006. The experimental design was made in randomized blocks with four replications and eighteen treatments. Mahalanobis distance was used as dissimilarity measure. The hierarchical method of medium connections (UPGMA) and Tocher’s  optimization method were applied. The results evidenced that the multivariate methodology make possible to identify genotypes of higher genetic divergence to use in sugarcane improvement programs. The best crossings options, considering divergence and yield, are between the clones RB992542 and RB992558 with the variety SP79-1011 and of the clone RB992558 with the variety RB92579. The characters apparent sucrose percentage contained in sugarcane juice, tons of sugarcane per hectare, apparent soluble solids contained in sugarcane juice percentage and stalk height were the major  determinants in the quantification of genetic divergence.