温度对红砂种子萌发的影响

Influences of Temperature on the Germination of Reaumuria Soongarica Seeds

荒漠植物能不能适应干旱半干旱地区极端的温度条件，主要看荒漠植物种子是否能够在极端温度下进行萌发及生长。本文对甘肃省兰州市的红砂种子在不同贮藏温度及不同萌发温度下萌发特性进行研究。将红砂种子在15 ℃、-5 ℃、-20 ℃、-30 ℃、-40 ℃的冰箱中贮藏一个月，其后放入15 ℃、20 ℃、25 ℃的光照培养箱中进行试验，试验在7d结束。结果表明不同贮藏温度下红砂种子的萌发率差异并不显著。初始萌发时间均在2 d - 2.5 d，总发芽势随着贮藏温度的降低而降低。而不同萌发温度对发芽率的影响随着贮藏温度的降低而变得有差异。萌发温度在25 ℃时，随着贮藏温度的降低初始萌发时间提前12 h。萌发温度对发芽势影响分为两方面。一方面，在萌发温度为25 ℃条件下，发芽势是随着贮藏温度的降低而升高的。另一个方面，在萌发温度为20 ℃、15 ℃条件下，发芽势是随着贮藏温度的降低而降低的。

The survive of desert plants under extreme temperature conditions in arid and semiarid area is depended on whether the seeds can germinate and grow under such conditions. This research conducted tests on the reaumuria soongarica seeds from Lanzhou City, Gansu Province, to explore the seeds＇ performance under different storage temperatures and different germination temperatures. During the tests, the seeds were stored in the refrigerators of 15 ℃,-5 ℃, -20 ℃, -30 ℃, -40 ℃ respectively for a month, thereafter were placed in solar incubators of 15 ℃, 20 ℃, 25 ℃ separately, the experiment lasted for 7d. The results showed that the germination rate of Reaumuria soongarica seeds under different storage temperatures were insignificant. The initial germination dates were 2~2.5d averagely, while the germination potential decreased along with the decrease of storage temperature. However, with the decrease of storage temperature, the influence of germination temperature became differentiated. Under the germination temperature of 25 ℃, With the decrease of storage temperature, the initial germination time would be 12h ahead. Thus, the effects of the germination temperature on germination rate was divided into two aspects, under the germination temperature of 25 ℃, the germination rate increased with the decrease of storage temperature; while under the germination temperatures of 20℃ and 15℃, the germination rate decreased with the decrease of storage temperature.