GENETIC EVALUATION OF RUBBER TREE HALF-SIE PROGENIES IN DIFFERENT REGIONS OF SAO-PAULO, BRAZIL

The objective of this paper was to evaluate the genetic potential of h alf-sib progenies of rubber tree [Hevea brasiliensis (Willd, ex Adr. d e Juss.) Mull. Arg.] in three different locations of the State of Sao Paulo, Brazil. For the study, progenies of 22 genotypes were obtained from a base population of Malaysia. Yield and vigour expressed by thre e tapping tests and four annual girth increment, respectively, were th e studied characters. The results of the analysis show that in each in dividual yield test and annual girth increment, evaluation for each lo cation, similar genetic variation were detected among progenies for bo th characters. In the combined analysis, genetic variations were detec ted among progenies for annual girth increment. The effect of location s was significant for all locations. Progenies x locations interaction was significant for the last three girth annual increments, which ref lected on the reduction of the heritabilities and, therefore, on selec tion for localities. The strict sense heritabilities at plant level we re similar to those obtained within the progenies. These heritabilitie s were lower than those obtained at mean progeny level for both charac teristics. The genetic gain estimates for selection among and within p rogeny showed considerable genetic advances revealing the possibility of successful selection within each trial.