Influence of rootstocks on scion growth of rubber tree in Sao Paulo State,Brazil

This paper was established in the experimental fields of Estacao Experiment al de Agronomia de Pindorama, SP, Brazil, in order to evaluate rootstocks v s. scion interaction in rubber tree, Hevea brasiliensis (Willd. ex Adr de J uss.) Muell. Arg. The clones involved were: IAN 873, RRIM 600, RRIM 701, PB 235, PR 107 and GT 1 grafted in six different rootstocks from illegitimate seeds of the clones IAN 873, RRIM 600, RRIM 701, PB 235, GT 1 and from uns elected seeds. The lay out used was that of randomized blocks in split-splo t design, with four replications. The outcome has shown that in the evaluat ion period the GT 1 and IAN 873 rootstocks were the ones which produced the mayor girth per plant, being 10.20% larger than that of unselected seeds. At the same time the clones studied pointed out that PB 235, RRIM 600 and P R 107 had a better achievement with an increase of 8.12% in the stem girth compared with RRIM 701 and GT 1 clones that had the worst development. The interaction rootstocks vs. scion was not significant.