Genetic divergence among sugarcane genotypes (Saccharum spp.) for cane yield attributes and quality determinants

The investigation was carried out at the Sugarcane Research Centre - Guneid (14, 48 - 15.00 degrees N) during the seasons 2003 - 04 and 2004 - 05. Twelve exotic sugarcane genotypes from Barbados, Guyana, Argentina and South India were tested in a randomized complete block design with four replicates. The objective was to quantify the genetic diversity among these genotypes regarding eleven cane yield and quality characters namely: stalk height, stalk diameter, internodal number per stalk; juice brix, juice pol, sugar recovery, juice purity, cane fiber and cane maturity percent, and yield of cane and sugar in Ton/hac. The results indicated that, the genotypes were grouped into six clusters based on the genetic distance using Mahalanobis's statistics. Higher inter-cluster distance was noticed between cluster IV and V (83.546) indicating high genetic diversity among two clusters. Thus, exploitation of genotypes within these two clusters as parents for crossing could produce good sugarcane segregants. The intracluster distance within cluster VI (7.226) and II (6.666) was very low indicating a close relationship of genotypes within each of these clusters. High cluster mean value for juice quality was recorded by cluster I whereas for cane and sugar yields, cluster VI was the best. It is suggested that genotypes within these two clusters could show greater potentiality for breeding purpose by virtue of their desirable characters.