药用植物桔梗的传粉效率与结实率研究

Pollination Rates and Seed Set in Platycodon Grandiflorus(Jack.) A.DC.

药用植物桔梗Ｐｌａｔｙｃｏｄｏｎ ｇｒａｎｄｉｆｌｏｒｕｓ（Ｊａｃｑ．）Ａ．ＤＣ．在自然授粉中结实率约为 １２％其花柱的授粉率较高的，达 ７７ ５％，为结实率的 ６． ４６倍．花柱头上的平均花粉量为 ５－１６个，但主要为来自白花的花粉，散粉期花粉活力较高．从不同处理结实率实验看，桔梗的有性繁殖主要依靠异花授粉，其自花授粉的结实率为１％．在影响结实率的诸多因素中，异花授粉的效率以及植物对异花授粉的依赖程度是重要因素．

The pollination biology of platycodon grandiflorus has been studied. Its seed set was 12% in natural comditions, the pollination rates were high to 77.5%, 6.46 gimes of its seed set. The mean number of pollen grains per stigma ranged from 5 to 16, most of the pollen grains were from self-pollination. The pollen viabiloty was strong in the emanationg-pollen period. The breeding system of platyoodon trandiflorus was dominantly xenogamous, and autogamy was about 1%. We consider that the lomitation and dependence of xenogamy are important factors among the factors influencing seed set.