不同温度对多年生禾草种子发芽的影响

EFFECT OF VARIOUS TEMPERATURES ON GERMINATION OF PERENNIAL GRASS SPECIESES

设置了６种恒温、５种变温，对２２种多年生禾本科牧草种子进行发芽试验，根据各温度下的发芽率、发芽指数、最初萌发时间等指标，来探讨发芽的最适温度。结果表明，供试种子在变温下的发芽率普遍高于恒温下，２０℃时种子在萌发的第９ｄ按发芽指数统计有１３种达最大值，所有品种的发芽指数对温度反应的排序为５＜１０＜１０～１５＜１５＜２０℃，各牧草种子的发芽最初萌发时间随温度的升高而缩短，发芽的最适温度因种和品种而异，本试验的２２种牧草发芽最适温度在１５～２５℃之间。

Optimum temperatures have been found out by examining germination rate, germination rate index and pregermination duration of 22 perennial grass specieses. under constant temperatures and 5 variant temperatures. Results were shown as following: germination rate was higher under variant temperatures than that under constant temperatures, germination rate index of 13 specieses reached maximum on 9th day under temperature of 20 ℃, response of all specieses to temperatures ranged as 5<10<10～15<15<20 ℃, pre-germination duration of all specieses decrease along with increase of temperature, optimum temperature varied with speciese, but was defined as 15～25 ℃ for 22 specieses.