保水处理对橡胶树叶片生理特性及胶乳产量的影响初探

以橡胶树品种‘云研77-4’为试材,采用盖膜、盖草和添加保水剂的处理方式,以常规管理（不覆盖）为对照,通过田间比较试验研究3种保水处理对橡胶树全年中不同生长阶段叶片生理特性及胶乳产量的影响。方差分析结果表明：盖膜、盖草和添加保水剂在干季均显著提高了土壤含水量,并显著影响了橡胶树叶片的可溶性蛋白（SP）、脯氨酸（Pro）、可溶性糖（SS）和蔗糖（Suc）含量;3种保水处理处理均不同程度的提高了胶乳产量。主成分分析结果表明：提取3个主成分,累计贡献率为84.8%,说明前3个主成分可反映原始变量的绝大部分信息;根据综合得分,各保水处理优劣顺序依次为：添加保水剂、盖草、盖膜、对照;橡胶树全年中不同生长阶段叶片生理指标综合表现优劣顺序依次为：12月、3月、1—2月、11月、6月、7月、9—10月、8月、5月、4月。因此,从本研究结果可以推断,各保水处理均能有效缓解季节性干旱对橡胶树生长的不利影响,在生产上可以根据橡胶树全年中不同生长阶段叶片生理指标综合表现选择合理的割胶时期。

Effects of Water-retention Treatment on the Physiological Characteristics and Latex Yield of Hevea brasiliensis

Rubber tree variety ‘Yunyan 77-4’ was selected as the test material. With conventional management (without covering) as the control, covering film, covering grass and adding water-retaining agent were adopted as the three water-retaining treatments. Through field comparative experiments, the effects of different treatments on the physiological characteristics of leaves and latex yield at different growth stages of rubber tree in the whole year were studied. The results of variance analysis showed that covering film, covering grass and adding water retaining agent significantly increased soil water content in dry season, and significantly affected the contents of soluble protein (SP), proline (Pro), soluble sugar (SS) and sucrose (Suc) in the leaves of rubber trees. The yield of latex increased by the three water retaining treatments. Principal component analysis showed that the cumulative contribution rate of the first three principal components was 84.8%, indicating that the first three principal components could reflect most of the information of original variables. According to the comprehensive score, the order of the advantages and disadvantages of each treatment was as follows: adding water-retaining agent, covering grass, covering film and the control. The order of comprehensive performance of physiological indexes of rubber leaves at different growth stages in the whole year was as follows: December, March, January-February, November, June, July, September-October, August, May and April. Therefore, it can be inferred from the results that all water conservation treatments can effectively alleviate the adverse effects of seasonal drought on the growth of rubber trees. In terms of production, a reasonable tapping period can be selected according to the comprehensive performance of physiological indexes of leaves at different growth stages throughout the year.