【作者】 盛丽娟；

【导师】 李德志；

【作者基本信息】 华东师范大学 ， 生态学， 2007， 硕士

【摘要】 克隆植物以克隆生长为基础形成的克隆构件性以及生理整合特性使克隆植物表现出比非克隆植物更为丰富的表型可塑性，在理论上也更容易适应异质性生境或胁迫生境。本文以匍匐茎型克隆植物结缕草（Zoysia japonica Steud.）为研究对象，应用实验生态学方法(稳定性同位素(¹³C)示踪技术)研究了结缕草在不同光照条件下表型可塑性响应和碳素生理整合特征，揭示了结缕草在胁迫的和异质的光环境中的生态适应对策。光照是影响植物形态建成、存活、生长发育、繁殖以及分布的基本资源和关键因素之一。本文研究了结缕草在不同程度的遮荫处理条件下的表型可塑性响应特征。结果表明，当结缕草受到遮荫时，其在生物量、叶型、克隆构型以及分株种群特征等方面均显示出基于光照强度的表型可塑性。除表现出与非克隆植物一致的“趋贫生长”特性外，还表现出一定的基于克隆构型可塑性的“觅食行为”。“趋贫生长”通常是非克隆植物获取生境中限制性资源的有效策略，而基于克隆构型可塑性的“觅食行为”通常是克隆植物有效利用生境资源的生态策略，在本次研究中观察到了克隆植物结缕草对这两种策略的权衡。碳素整合是克隆植物生理整合过程中非常重要的一部分，是克隆植物生存、生长、繁殖的物质基础。通过不同光照处理，研究了结缕草在同质／异质性光照生境中的碳素整合格局。结果表明：结缕草基株在不同光照条件下均发生广泛的同化物整合，引入¹³C的分株可同时将同化物向顶传输给较年幼分株和向基传输给较年老分株，但向顶传输的强度和范围均大于向基传输，说明结缕草基株内较年轻的分株相对于较老分株而言是同化物更有力的汇，而结缕草尖端因分生组织活动旺盛且自身尚不能或无法完全合成自身生长活动所需的同化物，因而是基株内同化物最有力的汇；基株内处于不同发育阶段的分株均可将自身合成的同化物向基传输给较老分株以及向顶传输给较年幼分株，但位于主匍匐茎基部和中部较老分株的同化物整合能力均弱于靠近主匍匐茎顶端的较年轻的分株，并且前者更倾向于将同化物传输给已形成的下级匍匐茎上的分株，因此，结缕草基株内存在着明显的以侧枝为相对独立单元的碳素生理整合单位；不同光照条件下结缕草的碳素整合格局也显示出一定的差异，局部遮荫处理实验说明：结缕草在受到胁迫时，能够改变其原有的碳素整合格局，在异质性光照生境中的整合格局与同质性生境中有所不同，克隆植物结缕草的同化物生理整合策略本身也具有一定程度的生态可塑性。更多还原

【Abstract】 Based on clonal growth, clonal plants formed clonality and physiological interation, which result in diverse phenotypic plasticity than non-clonal plants, and adaption to heterogeneous or stressful environments. The phenotypic plasticity of Zoysia japonica and the patterns of carbon physiological integration in different light conditions were studied applying the technique of stable isotope (¹³C), which revealed the adaptive strategies of Zoysia japonica in stressful and heterogeneous light environments.Light is one of the key factors affecting the morphogenesis, survival, growth, development, reproduction and distribution of plants. The phenotypic plasticity of Zoysia japonica in different levels of shading was studied. The results showed that when shaded, Zoysia japonica showed phenotypic plasticity in terms of biomass, leaf shape, clonal architecture and ramets population. Zoysia japonica specialized for scarce light like non-clonal plants, and also performed foraging behavior. Zoysia japonica showed tradeoff between the two strategies.Carbon physiological integration as the basis of survival, growth, reproduction and distribution of clonal plants is an important part of clonal integration of clonal plants. The results showed that extensive carbon integration existed in Zoysia japonica in different light conditions. The ¹³C absorbed was transported acropetally to the younger ramets and basipetally to the older ramets, but the intensity and range of acropetal translocation was stronger and wider than basipetal transportation, which suggested that the younger ramets was the stronger sinks of assimilates, and the apex was the strongest sinks of assimilate. Ramets at different developmental stages transported assimilate acropetally and basipetally. The capacity of carbon physiological integration of the older ramets were weaker than the younger ramets. Older ramets trended to transport more assimilate to the ramets of the lower-level branch. A relatively independent IPU for carbon tended to exist in the lower-level branch of Zoysia japonica. The pattern of carbon physiological integration changed under different light conditions. The local shading experiment showed that when ramets of Zoysia japonica were under stress, the original carbon integration pattern might change. Carbon integration pattern showed difference in homogenous and heterogeneous light environments. The strategy of integration of assimilates performed ecological plasticity in Zoysiajaponica.更多还原