在前些年,一些割胶试验的产量和树围增长量数据进一步证实了在橡胶树树龄和树围较小时开割,比达到常规树围(50厘米)时才开割更为有利。在SE·1/4试验区内,每株树都施用了不同量的氮、磷、钾、镁肥和长效磷和钾肥,提早开割树采用的割制是S/2,d/3(2×3d/7),五年来每公顷累积产量超过常规割胶树(S/2,d/3)3380公斤,即增产54％(表1)。这表明由于提早开割所增加的产量,在五年后还一直保持着。1979年所有 In previous years, data on the yield and bracing of some tapping tests further confirmed that it is more advantageous to cut the cut at the age of the rubber tree and when the brouhaha is small, and to cut it more than the conventional bough cut (50 cm). In SE.1 / 4 plots, different amounts of N, P, K and Mg fertilizers and long-term P and K fertilizers were applied to each tree, and cuttings used for early cutting were S / 2 and d / 3 (2 × 3d / 7). In the past five years, the cumulative yield per hectare surpassed the 3,380 kg of the conventional tree (S / 2, d / 3), which increased by 54% (Table 1). This shows that the increase in output due to early opening cuts remains unchanged after five years. All in 1979