鼠麴舅(Gnaphalium purpureum L.)種子發芽能力之週年變遷

Abstract

The purpose of this study would like to know the annual changes of the dry land weed seed germinability of Gnaphalium purpureum L. in Taiwan. The seeds were collected in Chiayi and buried into a 10 cm-deep upland soil, and then harvested monthly for two years. Seed germination percentage was tested under six different temperature regimes or buried into soil of 0.1 cm in depth. It was found that the germination rate of tested seeds was lower at 30/25℃ in the beginning of the experiment with light treatment. The high germination ability of buried seeds was observed while they were incubated at 15/10, 20/15, 25/20, 23/13 and 30/20℃ with light treatment and that was changed with seasonal fluctuation. However, seed germination at all temperature regimes was lower at the beginning with dark treatment. The tested seeds had stronger conditional dormancy at 30/25 and 30/20℃ with germination percentage near zero. Germination abilities of tested seeds among other four temperatures were similar with light treatment, but all seed germination abilities with dark treatment were lower than that with light treatment. Field experiments of buried seeds and fresh seeds showed that seed germination mainly occurred in winter. However, the high temperature from late spring to early autumn refarded seed germination.