VIGOR EVALUATION OF 6 DIFFERENT POPULATIO NS OF HEVEA ROOTSTOCKS

This study was undertaken aiming to evaluate and to select by their vi gor six different rubber tree [Hevea brasiliensis (Willd. ex. Adr. de Juss.) Muell. Arg.] rootstocks, GT 1, RRIM 701, PB 235, IAN 873, RRIM 600 and unselected seedlings for a better performance of the rubber in dustry of Sao Paulo State (Brazil). For correlations the characters st udied were: stem diameters (DC) height (AP), whorls number (NL) and av erage distance between the whorls of leaves (TL). The results of analy sis of variance showed significative differences among rootsocks conce rned to DC. AP and NL. The RRIM 600 rootstocks showed the least variab ility, and the heighest was that obtained from clone PB 235, with valu es of 22,88% and 28,12%, respectively. The correlation values between DC and AP and DC with NL were highly significatives. The correlatation coefficients values between NL and TL for all studied rootstocks were negative and highly significatives showing that as larger is the numb er of whorls of leaves, lesser is their size. The high correlation of DC with AP, and DC with NL, showed that it is possible to obtain vigor ous rootstocks through early selection for those characters.