新疆产药用植物黑果枸杞有性生殖产出差异的繁殖生态学研究

Reproductive Ecology Research on Populations of a Medicinal Plant( Lycium ruthenicum Murr. ) from Xinjiang Reveals Factors Affecting Fruit Production

由于黑果枸杞(Lycium ruthenicum)果实具有重要的保健价值,近年来倍受关注,但其野生资源正遭受着前所未有的采伐压力。目前关于影响黑果枸杞果实产量的有性生殖过程研究较少,本实验对新疆库尔勒地区6个不同生境的野生黑果枸杞居群开展了繁殖生态学观察,并对各居群的访花频率、访花昆虫种类、柱头花粉落置、胚珠数、座果率、结实率和单株果实产量等指标进行了比较分析。结果表明,访花频率与结实率、座果率具有显著正相关关系,说明传粉者是限制黑果枸杞有性生殖的关键因素之一;传粉者种类越丰富的居群其有性生殖产出越高,揭示了传粉昆虫的多样性和丰富度是影响黑果枸杞繁殖成功的重要限制因子。此外,和静县华侨农场和焉耆县霍拉山河沟的黑果枸杞居群生殖产出明显与其传粉成功率相偏离,进一步分析表明,风沙侵蚀和人为采伐对植株的破坏是影响这两个居群果实产量的重要原因。本研究结果对于野生黑果枸杞居群的保护及其人工规模栽培提供了重要的参考依据。

Recently, Lycium ruthenicum attracted substantial attention due to the high value of its fruits to human health. As a result, the wild resources are at high risk of loss and detailed studies on the sexual reproductive ecology of this important medicinal plant should be conducted for better conservation. We investigated factors affecting reproductive output of the plant using six wild populations from Xinjiang. We compared differences in pollination frequency, pollinator composition, stigmatic pollen load, and ovule production among the populations, as well as correlations with reproductive output namely, fruit set, seed set and fruit production per plant. Results indicated that pollination frequency was significantly correlated with fruit set and seed set, and populations with high diversity in pollinator types had higher reproductive output. These results suggest that pollinator resource was one of the limiting factors affecting reproductive output. We also found that two populations, from Huaqiao farm, Hejing county （H J3）, and Huolashan valley, Yanqi County （YQ2）, had unexpectedly low reproductive output. Detailed analyses indicated that flowers destroyed by sand-laden wind and artificial harvesting may also heavily reduce reproductive output. Our results provide valuable information for the conservation of this endangered plant and also on manipulation of artificial cultivation at a large scale.