The objective of this work was to evaluate the yield performance, and economic and physiologic aspects of four Asian clones Prang Besar of rubber tree [Hevea brasiliensis (Willd. ex A. Juss.) Muell. Arg.], in different tapping systems. The trial was placed at Santa Gilda farm, City of Guararapes, São Paulo State, Brazil, in a randomized block design with split-plot in time. The main treatments were PB 260, PB 235, PB 330 and PB 217 clones submitted to nine systems of tapping: ½S d/3.ET 2.5% 8/y; ½S d/3.ET 5% 8/y; ½S d/4.ET 2.5% 8/y; ½S d/4.ET 5% 8/y; ½S d/5.ET 2.5% 8/y; ½S d/5.ET 5% 8/y; ½S d/7.ET 2.5% 8/y; ½S d/7.ET 5% 8/y and ½S d/2 (check). The variables evaluated were: girth increment, dry rubber production, brown bast; it was also evaluated the economic viability. Results indicated the economical superiority of the ½S d/5.ET 2.5% 8/y and ½S d/7.ET 5% 8/y systems in PB 260 clone; ½S d/7.ET 2.5% 8/y system in PB 235 clone; and ½S d/3.ET 2.5% 8/y and ½S d/3.ET 5% 8/y in PB 330 and PB 217 clones, compared with the check. The smallest incidence of panel desiccation was observed in ½S d/7.ET 5% 8/y system, except for PB 235 clone.
Hevea brasiliensis; natural rubber; chemical stimulation; brown bast; economy