■草种子生产性能及其萌发特性的研究

Research of Seed Production Capability and Germination Characteristics of Koeleria cristata(L.) Pers

研究了来自内蒙古草原4个地区的■草种群的种子生产性能及其动态特征,分析了温度、药剂处理和保存期对■草种子萌发过程的影响。结果表明:(1)4个■草种群结实率差异均不显著,2年龄植株平均结实率为35.26%,平均净种子结实量为0.861g/株,来自大青山、希拉穆仁草原的■草结实量都显著高于锡林郭勒■草。(2)2～5年龄级的■草种群结实率均差异不显著,平均结实率为36.5%,3、4年龄植株的结实量显著高于其他两个年龄。(3)■草种子在25℃恒温下萌发率最高,平均萌发率为88.2%,低温可显著降低■草种子萌发率。在15℃下利用赤霉素处理的种子萌发率可提高20%～30%。■草当年种子萌发率和幼苗存活率最高,随着贮存期的增加,种子萌发率与存活率逐渐降低。

The objectives of this study were to confirm the seed production capability,dynamic characteristics,the effect of temperature,chemical treatment and storage period on seed germination of Koeleria cristata（L.） Pers from four regions in Inner Mongolia grassland.The results revealed that：（1）the difference of seed setting rate among 4 different populations of K.cristata were not significant,the mean rate of seed setting of two-year old K.cristata was 35.26%.The mean set amount of pure seed of each plant was 0.861g.However,the pure seed set amount of K.cristata from Daqing Mountains and Xilamuren grassland were significantly higher than that from Xilingol grassland.（2）There were no significant difference among the seed setting rate of four populations,the mean rate of seed was 36.5%.Compared each-age plant,the pure seed set amount of three-year and four-year plant were significantly higher than the other two age plant.（3）The optimum temperature of germination was 25℃,the highest average germination rate were 88.2%.And the rate of seed germination could be reduced significantly under the low temperature.Of the temperature 15℃,the rate of seed germination could be significantly increased by 20% to 30%,when the seeds were treated with Gibberellin.The influence of storage period was also significant on the rate of seed germination and seedling survival,of which the newly harvested seeds was the higher than the seeds for long storage period.