甘肃贝母种子灌浆特性研究

选用5年生甘肃贝母种株,在盛花期挂牌标记开花一致的植株,从开花后第5天开始测定籽粒千粒鲜、干重和含水量,对种子灌浆特性进行研究,旨在为其种子标准化采收提供理论和技术依据。结果表明,甘肃贝母种子千粒鲜重在开花后66d达到最大,随后迅速下降到接近干重的水平。籽粒干重变化的趋势呈“S”型曲线,符合Logistic方程,快增期在花后41～66d,至花后97d灌浆结束。灌浆速率呈“快-慢-快-慢”规律,因降水出现1次低谷,籽粒脱水速率随灌浆进程而加快,含水量持续下降,籽粒含水量下降最快的时期为灌浆高峰结束期。籽粒干重与脱水速率和灌浆持续期均呈极显著正相关,而与籽粒含水量呈极显著负相关。甘肃贝母种子灌浆速率受天气的影响大,籽粒脱水加快、干重趋于稳定是种子成熟的标志,采收期应在花后77～82d(7月底-8月初),种果尚未开裂,种子含水率在40%以下,茎杆尚未完全枯黄时为最佳。

Studies on grain filling characteristics of Fritillaria przewalskii

Cards were hung as a flower sign during blossom in lustrum Fritillaria przewalskii plants cultivated in Gannan, Gansu. The grain fresh weight, dry weight and water content in capsules of the plants were measured in period time after 5 d following the day. The grain filling characteristics were studied in order to provide theoretic basis for its seed standard production. The results showed that the 1000-grain fresh weight increased and got at the highest value on the 66th day following blossom, and then rapidly decreased to the level near its dry weight, which fitted to Logistic equation with a rapid increase during 41-66 d after blossom and finished at the end of 97 d. The grain filling rate showed 'fast-slow-fast-slow' pattern and went to bottom one time because of raining. The grains dehydrated faster and faster with filling duration elongation and the water content decreased to the end. The fastest decreased time in water content means the finish time of the grain maximum filling. The seed dry weight were positively and significantly related with the grain dehydration rate and the filling duration while negatively and significantly related with water concentration. All above revealed that the seed filling is affected by weather. The fast dehydrating rate and the stability of dry weight in seeds are the important indicates for seed maturation. The best harvest time should be during 77-82 d following blossom (at the end of July or beginning of August), during which the water content in the seeds should be lower than 40% and the seed capsules are not dissilient with still non-perishing stems.