Genetic divergence among Hevea primary clones

Abstract

The use of rubber tree hybrid clones in breeding program frequently requires information about genetic potential, performance as a parental, and evaluation of genetic divergence among clones. Aiming at studying the genetic divergence among clones through the analysis of the principal components and the Mahalanobis generalized distance (D2), 100 Hevea clones were evaluated in two replications and ten plants per plot, at spacing of 2,0 x 1,5 m. One and two-year old plants were evaluated for eight and seven traits, respectively. The scores of the first and second principal components explained about 80% of the variation observed within two years. The clustering procedure proposed by Tocher applied to Mahalanobis distance shown in the first year was different in comparison to that of the second year. The number of clustering of the first year was superior in relation to that of the second year. Special emphasis was given to the moderate level of divergence between the groups as well as to the average of the traits of the clones evaluated as choice of parents.