金沙江干热河谷麻疯树结籽率及其影响因素研究

Researches on the Seed-setting Rate of Jatropha curcas L. in the arid valleys of the Jinsha River and its Influential Factors

结籽率是度量雌性适合度与生殖效率的指标之一,结籽率低也是麻疯树高产稳产面临的问题之一。本文从传粉受精、构件与土壤资源三方面测定了不同环境与处理麻疯树林分的结籽率。攀枝花市麻疯树结籽率为77.3%(浮动在73%～91%之间)和败育率为4.3%(浮动在2.1%～5.8%之间)。人工辅助授粉提高了结籽率5%;土壤厚度不同样地之间结籽率相差5%;不同构件分布位置之间结籽率相差7%;遮光与未遮光林分结籽率相差5%;修枝处理使得结籽率达到92%,在统计上达到了显著水平。这些数据都表明,麻疯树结籽率存在明显的花粉限制、资源限制和结构限制。分析表明,结籽率与败育率呈现负相关,且结籽率提高就存在败育率的轻微而不显著的降低,表明果实内胚胎发育对资源利用存在权衡关系。构件特征对结籽率和败育率没有作用,可能其对生殖行为的调节作用发生在生殖包装的果实一级。麻疯树胚胎发育存在多种类型,表明其败育具有阶段性。在生产上,土壤改良、优化构型和人工养蜂辅助授粉能提高结籽率和生殖效率。

The seed-setting rate is one of indexes indicating the female fitness and reproductive effect.This paper deals with the plant seed-setting rate variety,according to three hypotheses,such as pollinator limitation,resource limitation and architecture limitation.It is necessary to understand the limiting factors of the seed-setting rate for high yield and stable production of Jatropha curcas in order to propose the solution strategy in practice.In this paper,the seed-setting rate of J.curcas was determined under different environment and treatments from three terms of pollnation,modular distribution and soil resource.In total,the seed-setting rate in Panzhihua City was 7.3% varying form 73% to 91%,and the aborted ratio was 4.3% varying form 2.1%～5.8%.Artifial treatment of adding pollination and deeper soil layers both increased the seed-setting rate by 5%,and light-shaded forest decreased the seed-setting rate by 7%,but branch-pruning treatment could make the seed setting rate reach 92%.All these demonstrated that the varied seed-setting rate was adjusted by the pollination limitation,resource limitation and architecture limitation.Analysis indicated that the nagetive correlation appeared between the seed-setting rate and the aborted ratio,implying that the tradeoff relation existed during the process of seed development.Modular size had no effect on the seed-setting rate and the aborted ratio,and the function of modular size on the repoductive behavior happened in the fruit rank of reproductive package.The embroyonic development of J.curcas had many types,indicated that the abortion had phase features.In practice,it is necessary to improve soil,optimize the tree architecture and use artifitial bee for enhancing the seed-setting rate and seed yield of J.curcas forest.