Am J Bot. 1997 Mar;84(3):393.
Eritrichum aretioides is a gynodioecious species with female and hermaphrodite individuals. In populations on Pennsylvania Mountain in central Colorado (USA), the frequency of females ranges from 22 to 41%. Flower number and the number of seeds produced per flower were similar in hermaphrodites and females. However, hermaphrodites produced larger flowers, while females produced larger seeds (P < 0.05 for both). In the field, seed germination was higher for seeds from females than for seeds from hermaphrodites (20 vs. 9% germination; P < 0.05). Unvisited flowers and open-pollinated flowers of hermaphrodites had similar pollen receipt (approx 20 pollen grains per stigma), but seed set following autogamous pollination was significantly lower than seed set following natural pollination. This finding indicates that hermaphrodites have a barrier to selfing and implies that the larger seed size and greater establishment advantage of offspring from females is unlikely to have resulted from female outcrossing advantage. Rather, differences in the quality of seed progeny between morphs probably reflect a trade-off in sexual allocation or pleiotropic effects of the sex-determining genes.
长角果薹草是一个雌雄异株的物种，存在雌性和两性个体。在美国科罗拉多州中部宾夕法尼亚山上的种群中，雌性个体的频率范围为 22%至 41%。两性个体和雌性个体的花数和每朵花产生的种子数相似。然而，两性个体的花更大，而雌性个体的种子更大（两者均 P < 0.05）。在野外，雌性个体的种子比两性个体的种子具有更高的发芽率（20%对 9%；P < 0.05）。未被访问的花和两性个体的异花授粉花具有相似的花粉接收量（每个柱头约 20 个花粉粒），但自交授粉后的结实率明显低于自然授粉后的结实率。这一发现表明，两性个体存在自交障碍，这意味着雌性个体的后代具有更大的种子大小和更高的建立优势，不太可能是由于雌性异交优势导致的。相反，不同形态之间种子后代质量的差异可能反映了性分配的权衡或性别决定基因的多效性效应。
