光果甘草与乌拉尔甘草开花与传粉方式对生殖及种间关系的影响

摘要

通过对光果甘草和乌拉尔甘草花期物候和访花昆虫行为的观察及人工授粉实验,探讨开花模式及传粉方式对生殖成功及种间关系的影响.结果表明:(1)两种甘草的种群水平花期重叠时间长达21 d,均表现出“集中大量开花”模式,但乌拉尔甘草呈现分批渐次开花趋势,这对提高生殖成功率,避免近交衰退,维持物种的稳定具有重要意义.(2)两种甘草的访花昆虫在种类和数量上有所不同,但具有共同传粉者——宽板尖腹蜂、意大利蜂和紫木蜂.(3)以乌拉尔甘草为母本、光果甘草为父本的种间杂交结实率为48.3％；以光果甘草为母本、乌拉尔甘草为父本的种间杂交结实率为39.4％,说明种间杂交亲和,不存在生殖障碍.研究认为,花期重叠、共有传粉昆虫及种间杂交亲和使光果甘草与乌拉尔甘草自然种群杂交种的形成成为可能.%Effect of flowering mode and pollination on reproductive success and interspecific relationship of Glycyrrhiza glabra L. and Glycyrrhiza uralensis Fisch. were studied by flowering phenology observation, pollinator observation, hand-pollination experiments. (1) Their overlapping time of the florescence was 21 days, both G. glabra L. and G. uralensis Fisch demonstrated "concentrate a large number of flowering mode", but G. uralensis Fisch. was batches gradually flowering. And that'have great significance for improve the reproductive success rate, avoid inbreeding depression and maintain the stability of the species. (2)Their pollination insects are different in numbers and varieties, but Coelixys afra Lepeletier,Apis mel-lifera Linnaeus and Xylocopa valga Gerstaecker pollinate for both of them. (3) The rate of fruitage in crossing combination of "♀G, uralensis×♂G. glabra" was 48. 3% , the "♀G. glabra× ♂G. uralensis" was 39. 4%. This means that hybridization between G, glabra L. and G. uralensis Fisch. are compatible and nd reproductive obstacles. Studies have shown that overlapping time of the florescence,common floral visitors and compatible of hybridization may be important conditions to successfully make interspecific pollination and speciation for natural hybrid species of two Glycyrrhiza L. species.