Paeonia delavayi (Peaoniaceae),the largest and the most concentrated population in Shangri-La,Yunnan Province,China,was investigated to analyze the characteristics of flower and breeding system by the detections of pollen viability,stigma receptivity period,pollen-ovule ratio (P/O) and bagging test for successive three-year observation and experiment.The results are as follows:The florescence of P.delavayi is from mid-May to late June with anthesis period of 6-9 days,and maintained a high percentage of damaged seeds to promote early loose powder of stamen ; The flowers begin disseminating pollen from inside after 1-2 days of petals opening,can maintain 5-6 days,and the activity of pollen can keep longer at normal temperature; The stigma keep a high seeds rate between one day before the petals open to three days after the petals open,and the characteristics of disseminating hysteresis is defined as stamens post-maturation; P/O value is from 6 124 ∶ 1 to 9 713 ∶ 1,suggesting that the larger quantity of pollen can increase the higher seeding rate; By bagging test,P.delavayi has no self-pollination and apomixes phenomenon with a weak capacity of the anemophily; Artificial geitonogamy with strains of different flowers can produce a small amount of mature seeds with low plumpness ; The seed setting rate of artificial xenogamy and natural pollination were higher than the others.P.delavayi is cross-pollination plant,and the seeds depend on insect activities for pollination in natural conditions.%以滇牡丹(Paeonia delavayi)种群数量最大、分布最集中的香格里拉群体为研究对象,通过3a的连续观察,运用花粉活力检测、柱头可授期检测、花粉—胚珠比(P/O)、套袋试验等分析其开花特征及繁育系统.结果表明:滇牡丹种群整体花期为5月中旬至6月中下旬,单花花期6～9d,花朵虫食率高并促进雄蕊提前散粉;正常发育的滇牡丹花瓣打开1～2 d后自内向外开始散粉,可持续5～6 d,常温下花粉活力持续时间较长,柱头在花瓣打开前1d至打开后3d授粉成功率均较高,散粉滞后可认为是雄蕊后熟；P/O值为(6 124 ～9713):1,花粉量大,为较高授粉成功率提供了可能性；繁育系统中不同套袋试验表明,滇牡丹不存在自花授粉和无融合生殖现象,具有较弱的风媒传粉能力,同株异花能产生少量种子,但种子量少且饱满度较低,人工异株异花授粉和自然杂交结实率最高.繁育系统研究认为滇牡丹应为以昆虫为主要媒介的异花传粉植物,自然条件下种子的形成主要依赖于昆虫传粉活动.
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