Abstract
Experiments were conducted to examine the physiological variation of Poa annua L. collected from 83 golf courses throughout Japan. Seed dormancy, light and low temperature requirements for seed germination were investigated. When 83 populations were divided into 5 groups (Kanto, Shizuoka, Kyushu, rough and fairway populations), no considerable differences among populations were observed for all measurements except the light requirement in Kyushu population. Furthermore, histogram and correlation analyses indicated that seed dormancy is more variable than the low temperature requirement within Poa annua L. populations and a positive relation exists between seed dormancy and the low temperature requirement.
