白三叶(Trifolium repens L)无性系植物分株间的生理整合作用

PHYSIOLOGICAL INTEGRATTION AMONG INTERACLONAL RAMETS ON THE CLONAL WHITE CLOVER (Trifolium repens L ) POPULATION

研究了白三叶无性系植物种群，在相互连接的分株之间生理上相互依存的程度。结果显示子代在生理上取决于母株资源的转移，这一依赖性随时间而下降。相互连接的分株，一部分被遮荫至１０％，而照光分株光合速率明显增加。光被限制期间，分株将重新整合，遮荫分株无性系中由其它分株提供同化物。在子代匍匐茎数目和长度上有一个权衡。当资源受限制时，产生极少较长的子代匍匐茎，结果提高了子代能够占据更有利条件的可能性。在分株之间，生理整合作用降低了子代建立所面临的危险，使同源分株在资源的可利用能力上整合到一个局部的异质环境，增加同源分株间的竞争能力，缓冲所面对的局部微生境的选择。

Clones of white clover were studied to determine the degree of physiological interdepency among interconnected ramets The results show that new daughter ramets are physiologically depent upon resources translocated from their parental clone and that this dependency reduces with time Rates of photosynthesis increased in the remaining illuninated ramets when one of the ramets within each of some connected ramets was shaded to 10% of sunlight The results show ramet become rentegrated during periods of light limitation Other ramets supply shaded ramets in resource When resource limited they produce fewer but longer new stolon and increase probability of encountering more favorable conditions Due to the physiological integration ramets reduces the establishment risks of new daughter ramets A genet enables to integrate local heterogeneity in resource a vailability The results increased competititive ability of ramets and buffered against patch selection