三种甘草属植物的种间杂交亲和性及杂交种子活力

通过新疆分布的3种甘草属植物——乌拉尔甘草（Glycyrrhiza uralensis）、光果甘草（G．glabra）和黄甘草（G．eurycarpa）的人工杂交试验，比较了杂交结果率、杂交种子的萌发参数、幼苗成活率等指标，并对杂交授粉后花粉管萌发、生长过程进行荧光观察，旨在探讨3种甘草属植物的种间杂交亲和性及杂交后代种子活力。结果表明：（1）种间杂交结果率最高为96．67％，最低为55．62％，说明3种甘草种间杂交配子亲和性较高；（2）荧光显微观察表明，各杂交组合在授粉后0．5～2h内花粉均可在柱头上大量萌发，在授粉后48h内花粉管均可到达子房与胚珠受精，说明三种甘草种间杂交不存在配子隔离障碍；（3）杂交种子萌发率、发芽指数、平均萌发时间和幼苗成活率与自然结实种子无显著差异，种间杂交种子活力较高，幼苗成活率均为75％以上。以上结果表明3种甘草属植物的同域分布区，在相同传粉途径下，这三种甘草属植物的种间隔离机制不完善。有发生自然杂交并形成杂交区的可能。

The Cross Compatibility and Hybrid Seed Vigor among Three Glycyrrhiza Species

In order to discuss the cross compatibility and hybrid seed vigor of sympatric species among G. uralensis, G. glabra and G. eurycarpa distributed in Xinjiang, the cross fruiting rate, the pollen germination on stigma, the pollen tube growth in style after cross pollination and germination parameters of hybrid seeds were analyzed. Results showed that there was highly cross compatibility among these three Glycyrrhiza plants and their hybrids seeds were highly vigor. It suggested that the interspecific isolation mechanism of the three Glycyrrhiza plants was weak. Moreover, the natural hybridizations may occur and form natural hybrid zone.