黄花角蒿(Incarvillea sinensis var. przewalskii)开花动态及繁育系统的研究

Flowering Dynamics and Breeding System of Incarvillea sinensis var. przewalskii

通过野外定点观察，运用花粉-胚珠比、联苯胺-过氧化氢法、杂交指数、人工授粉和套袋试验等方法，对黄花角蒿（bwarvillea sinensisvar．przewalskii）的开花动态及繁育系统进行了研究。结果表明：黄花角蒿种群花期一般为6—9月，单花花期一般为2～3d，花雌雄异熟，雄蕊先熟，雌雄蕊异位。单花花期依其形态和散粉特征可分为散粉初期、散粉盛期、散粉末期、凋谢期4个时期。黄花角蒿花粉一胚珠比为331．3，杂交指数等于5，结合人工授粉和套袋实验结果可以确定该物种的繁育系统为异交，部分自交亲和，需要传粉者。套袋实验及实地观察显示黄花角蒿为虫媒传粉。

Flowering and breeding characteristics are important for understanding the plant population reproduction characteristics. In this paper, the flowering dynamics were observed in the fields and the breeding system of Incarvillea sinensis var. przewalskii was studied by using the data of pollen/ovule ratio （P/O）, pistil recipient phase, out-crossing index（ OC!）, pollen viability and bagging experiments. The results showed that the flowering period of I. sinensis var. przewalskii population lasted about three months （from June to September）. The life span of individual flower was generally 2 - 3 d. During the flowering course, the stamen matured before pistil and there was obvious herkogamy. The flowering course for one flower of this species can be divided into four periods based on the flower morphology and anther dehiscence： initial dehiscence, full dehiscence, terminal dehiscence, withering period. The pollen/ovule ratio of 1. sinensis var. przewalskii is about 331.3, and its out-crossing index is 5. Combining with the result of emasculation, bagging and artificial pollination, the breeding system of this species was determined to be out-crossing, partially self-compatible and entomoplily plays a larger role in the process of pollination. According to bagging experiments and field observations, it can be inferred that the species is insect pollination.