不同浓度乙烯利刺激割胶对大丰95产量及生理参数的影响

【目的】分析不同浓度乙烯利刺激割胶对橡胶树大丰95干胶产量及其相关生理参数的影响,为制定适宜大丰95的割胶制度提供参考依据。【方法】采用S/2d3割制对开割3年后的大丰95并涂施不同浓度(0、0.25%、0.50%和0.75%)的乙烯利,测定分析各处理胶树的干胶产量、干胶含量及胶乳硫醇、蔗糖、无机磷、镁离子含量、排胶初速度和堵塞指数等生理参数。【结果】在0.25%和0.50%乙烯利刺激下大丰95的干胶净增产率分别为15.3%和26.2%,乙烯利刺激浓度为0.75%时干胶产量随刺激浓度增大而增加的趋势不明显,干胶含量开始极显著下降(P0.01),无机磷持续显著增加(P0.05,下同),排胶初速度、堵塞指数及硫醇、蔗糖和镁离子含量均下降。采用乙烯利刺激割胶的大丰95干胶含量与乙烯利刺激浓度呈显著负相关(R=-0.8847),干胶产量与乙烯利刺激浓度呈显著正相关(R=0.9705)。【结论】采用S/2d3低频割制配合采用0.25%和0.50%乙烯利刺激开割3年后的大丰95橡胶树可取得较好的增产效应,胶树死皮率未明显增加,对胶树生长的影响也较小,可在大丰95割胶生产上推广应用。

Effects of ethrel stimulation with different concentrations on yield and physiological parameters of rubber tree Dafeng 95

Objective]In order to provide reference for rubber tree Dafeng 95 to design appropriate tapping system,rubber yield and physiological parameters related to rubber producing of rubber tree Dafeng 95 with ethrel stimulation with different concentrations were analyzed.Method]Rubber tree Dafeng 95 being tapped for three years were used as material. Dafeng 95 was tapped with half spiral upward cut every three days(S/2d3),stimulated by ethrel with different concentrations(0,0.25%, 0.50%and 0.75%). Parameters including dry rubber yield,dry rubber content,contents of latex thiol,sucrose,inorganic phos-phorus and magnesium ions,initial flow rate,plugging index under different treatments were analyzed.Result]The dry rubber net yield increment rate of Dafeng 95 under 0.25%and 0.50%ethrel stimulation were 15.3%and 26.2%respectively,but when the ethrel concentration increased to 0.75%,the yield were not increased obviously as the concentration went up,and the dry rubber content were decreased significantly(P<0.01). Inorganic phosphorus content continued rising significantly(P<0.05,the same below),initial flow rate,plugging index,contents of latex thiol,sucrose and magnesium ions were decreased . The dry rubber content of Dafeng 95 stimulated by ethrel had significantly negative correlations with ethrel concentration(R=-0.8847), and significant positive correlations were found between dry rubber yield and ethrel concentration(R=0.9705).Conclusion]The low frequency tapping system S/2d3 with 0.25%and 0.50%ethrel stimulation for rubber tree Dafeng 95 after being tapped for three years can achieve suitable yield increase. The tapping panel dryness rate does not increase obviously. And this tapping system has light impact on rubber tree growth. Therefore it can be applied to planting of rubber tree Dafeng 95.