柴胡种子灌浆动态及发芽特性研究

Grain filling dynamics and germination characteristics of Bupleurum chinense seeds

以三年生柴胡为研究对象，对其种子灌浆及发芽特性进行研究，旨在为提高柴胡种子质量提供科学依据。结果表明，柴胡种子干物质积累趋势呈“s”型曲线，快增期在花后25—34d，开花后46d灌浆基本结束。灌浆速率呈“快一慢一快．慢”规律。开花后28d开始柴胡种子的灌浆速率迅速下降，至开花后43d后趋于稳定，种子脱水速率和种子千粒鲜重达到最大。种子发芽质量与千粒重呈极显著正相关，与种子含水量呈极显著负相关。柴胡种子应在花后52d左右采收最佳，此时种子含水量10％左右，发芽率为34．33％。

Bupleurum chinense used in the study were cultivated in the experimental fields of Gansu agricultural University for three years. The seeds of B. chinense were collected every 3 days 10 d after the blossom. The result showed that the 1 000-grain fresh weight reached the maximum 43 d after the blossom and then decreased rapidly, at the mature period the fresh weight of seeds were falling to the same level of the dry weight. The dynamic change of the grain dry matter accumulation showed as an S-shape curve, the rapid increase stage was 25-34 d following the flower, and the grain filling was ended 46 d after blossom. Grain filling rate was under the law ＂fast-slow-fast-slow＂. And there were two peaks of grain filling rate appeared, after reached the second peak 28 d after the flower the filling rate decreased rapidly and stayed steadily 43 d after flowering. The dehydration rate was also measured at its maximum 43 d fol- lowing flower. The indexes of seeds all reached the top 52 days following the blossom, when the germination rate reached the peak （34.33%） and water content of seeds was near 10%. The rate of germination and the 1 000-graid weight of seed showed significant positive correlation, while the water content of seeds was found significant negatively correlation with germination percentage. So the best time for harvest should be 52 d after flowering （9 month）, the seeds collected at that time showed both high quality and germination rate.