Performance of Amazonian rubber tree clones in the plateau region of the State of São Paulo, Brazil

O objetivo deste trabalho foi avaliar a adaptabilidade e expressão fenotípica de caracteres superiores de dez clones amazônicos de seringueira (Hevea spp.) no planalto do Estado de São Paulo em um período de 10 anos, obedecendo ao delineamento de blocos ao acaso com três repetições e parcelas lineares de seis plantas. O clone IAN 3156 foi o mais produtivo, com média de 65,57 g de borracha seca/árvore/sangria, no período de quatro anos, seguido pelo clone RO 45 com 52,29 g de borracha seca/árvore/sangria, enquanto o clone-testemunha, RRIM 600, produziu 41,04 g/árvore/sangria. Todos os clones apresentaram crescimento vigoroso. O perímetro do caule na abertura do painel variou de 37,01 cm (IAN 3193) a 49,41 cm (IAN 4493). A porcentagem de plantas aptas à sangria variou de 30,0% (IAN 3703) a 93,75% (IAN 6323). Exceto os clones IAN 3156 e IAN 4493 com 7,00 mm e 6,32 mm, respectivamente, todos os outros clones apresentaram espessura de casca virgem inferior ao clone RRIM 600, que apresentou 6,18 mm. O clone IAN 3193 apresentou maior incidência de quebra do ponteiro pelo vento. Todos os clones estudados apresentaram baixa incidência de secamento de painel. O bom desempenho dos clones IAN 3156, RO 45, Fx 3899 e IAN 4493 permite que possam ser experimentados em larga escala, envolvendo diferentes ambientes no Estado de São Paulo.The objective of this paper was to evaluate, for a period of 10 years, the adaptability and phenotypic expression of superior characters of 10 clones of rubber tree (Hevea spp.) grown in the plateau of São Paulo State, Brazil. The clones in the field were arranged in a randomized block design with three replicates and six plants per linear plots. The results showed that the clone IAN 3156 recorded highest yield (65.57 g/tree/tap) followed by RO 45 (52.29 g/tree/tap), whereas the control clone RRIM 600 recorded 41.04 g/tree/tap over four years of tapping. All selected clones were vigorous, with girth range at opening varying from 37.01 cm (IAN 3193) to 49.41 cm (IAN 4493). The percentage range of plants able for opening were 30.0% for IAN 3703 to 93.75% for IAN 6323. Except for IAN 3156 with 7.0 mm and for IAN 4493 with 6.32 mm other clones had low thick virgin bark at open compared to the control clone RRIM 600, which recorded 6.18 mm. Concerned to wind damage, except for IAN 3193 all the studied clones experienced low incidence of wind damage. All clones showed low to very low incidence of tree dryness. A complementary evaluation of the best clones (IAN 3156, RO 45, Fx 3899 and IAN 4493) in different environment of the São Paulo State is suggested, to evaluate besides yielding other secondary characters with the purpose of future recommendation of planting material in large scale