降水量及种植时期对虎尾草生长和繁殖的影响

Coupled influence of different precipitation regimes and sowing dates on the growth and reproduction of Chloris virgata

通过分析虎尾草植株产量和种子产量的变化规律,研究了降水量和种植时期对虎尾草生长和繁殖的影响.结果表明:低降水量使虎尾草地上、地下生物量降低,延迟种植降低了植株地上和地下生物量;种子的千粒重随降水量的增加显著增加,但6月15日种植的虎尾草千粒重最小;种子产量在高降水量条件下最大,最早种植的植株种子产量最高,最晚种植的植株种子产量最低;虎尾草抽穗率随降水量的增加显著增加,高降水量条件下抽穗率最大,且各降水量条件下最晚种植的虎尾草抽穗率最大;不同种植时期虎尾草成熟度基本具有相同的变化规律,在低降水量条件下成熟度最低,6月15日种植的植株种子成熟度最低.降水量和种植时期的变化对虎尾草生长和繁殖具有重要影响.

The changes of plant biomass and seed yield were investigated to reveal the effects of different precipitation regimes and sowing dates on plant growth and reproduction.The results showed that low precipitation and late sowing decreased above and below biomass.Thousand seed weight increased significantly with the precipitation levels.However,the thousand seed weight was lowest on 15th June.Seed yield reached the highest value under high precipitation regime,and early sowing resulted in high seed yield too.The highest seed yield was at T_(1) and the lowest seed yield was at T_(3).Heading rate increased with the level of the precipitation and the highest value occurred under high precipitation treatment.Furthermore,heading rates were highest at late sowing date under all the precipitation levels.The trends of ripeness behaved similar at different sowing dates.And the ripeness were lowest at low precipitation.The smallest values of ripeness occurred on 15th June.Therefore,precipitation and sowing date affected the growth and reproduction of Chloris virgata.