イタドリのそう果と幼苗における形態的特性の高度的変異

概要

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Polygonum cuspidatum Sieb. et Zucc. produced larger and heavier achenes with increasing altitudes of its habitats from basal zone to alpine zone, and the form of its achene's wings was also different. After seed germination at the experimental field in montane zone, the growth of the seedlings derived from high altitudes was more rapid in the early stage of their growth than that from low altitudes. But, three months later, germination seedlings derived from alpine zone showed a dwarf type on their aboveground parts. Some of the seedlings grown in this area came into flower within the year, and developed male flowers only on the plants derived from low altitudes while both male and female or female flowers only appeared on those from high altitudes. Such differences in some of the morphological characteristics between the achenes and the seedlings derived from low and high altitudes seem to be caused by the different levels of altitudinal climatic stress from their original habitats, and seem to be genetic. It is suggested that P. cuspidatum has developed an alpine ecotype in high altitudes where climatic conditions are severer.
日本生態学会の論文
1992-08-10