野生高乌头开花习性及种子灌浆特性研究

利用甘肃永登县野生高乌头植株为研究材料,标记初花期一致的植株,每天测定单株开花数和蓇葖果数,并每隔3 d测定蓇葖果种子数、粒重和体积,对其开花结果动态和种子灌浆特性系统研究,旨在揭示其开花结果习性及其种子灌浆规律,为探寻高乌头种子发育规律及适宜采收期提供科学依据。结果表明,野生高乌头植株主花序花蕾自下而上依次开放。单花开放后第3天形成蓇葖果,第15天种子成形,并开始脱水形成干物质积累。单株开花数等于蓇葖果数,基本不落花,但仅主花序中部及以下部位蓇葖果具成熟种子。在种子整个灌浆过程中,百粒鲜重和干重的变化动态均呈“S”型曲线,符合Logistic方程。籽粒鲜重快增期在花后7～21 d,最大增长速率出现在花后14 d,在花后27 d达到最大,而干物质积累快增期在花后16～30 d,最大积累速率出现在花后23 d。开花36 d后蓇葖果脱落,种子灌浆和株上脱水中断,导致种子含水量达50%以上,采收后种子在快速脱水过程中可能形成深休眠特性,说明高乌头种子适宜采收期为开花后第36天左右(8月中下旬),蓇葖果尚未开裂时及时分批采收为宜。

A study on blossoming habit and seed filling characteristics of wild Aconitum sinomontanum

Wild Aconitum sinomontanum plants growing in Yongdeng county, Gansu were marked with labels at the beginning of the blossom stage to explore their blossoming-fruiting habit and seed filling pattern. The blossoming-fruiting dynamic and the seed filling characteristics were studied by measuring the flowers, follicles, seed shape and size of the plants once every three days to provide a scientific basis for the seed development pattern and best harvest time. The buds in the wild plants gradually opened from base to top in the main anthotaxys. The flowers fruited after 3 days and the seed shape appeared in the fruit 15 days after blossom, and then the grain began to dehydrate and dry matter accumulated. The flowers developed to follicular fruits without shattering, but only the middle and basal fruits in the anthotaxys had plump seeds. In the seed filling process, the change of 100-seed fresh and dry weights all showed an “S” shaped curve which fitted to a Logistic equation. The maximum rate of increase appeared on the 14th day following blossom for the seed fresh weight and the 23rd day for the seed dry matter accumulation. The seed fresh weight increased rapidly from 7 d to 21 d and reached the highest value on the 27th day after blossom, whereas the grain dry weight increased rapidly from 16 d to 30 d. The follicular fruits fell off after 36 d following blossom resulting in interruption of the filling and the dehydration process to 50% water content in the seeds, which probably led to the deep dormancy characteristics during fast dehydration. The best harvest time for the seeds should be approximately 36 d following blossom (from the middle to the end of August) during which time the follicular fruits are not dissilient and the seeds should be harvested in timely installments.