Sex ratio variation in populations of a dioecious desert perennial, Simmondsia chinensis
Sex ratio variation in populations of a dioecious desert perennial, Simmondsia chinensis
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雌雄异株的沙漠多年生西蒙得木种群的性别比变化
DOI：
10.2307/3544403
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发表时间：
1984
期刊：
影响因子：
--
通讯作者：
N. Waser
中科院分区：
文献类型：
--
作者：
N. Waser
雌雄异株的风媒传粉灌木希蒙得木在墨西哥、亚利桑那州和加州的索诺兰沙漠中很常见。在两个相距甚远的地点，对几年来的性表达的调查表明，男性略多于女性，但始终在整体上;性别比例变化沿着水分梯度与男性偏见往往是最强的最干燥的网站;和性表达是独立的植物大小，而不是不稳定的，每年。这些结果进行了比较，从其他研究Simmondsia性别比例，并预测的理论，包括自适应理论，性表达。我的结论是，调查本身不能区分替代的因果假设，实验和人口统计学研究将是必要的，在一般情况下，阐明植物的性别表达的变化。
The dioecious wind-pollinated shrub Simmondsia chinensis is common to much of the Sonoran Desert of Mexico, Arizona, and California. A survey of sexual expression over several years at two widely-separated sites indicates that males slightly but consistently outnumber females on the whole; that sex ratios vary along moisture gradients with male bias tending to be strongest in the driest sites; and that sexual expression is independent of plant size and not labile from year to year. These results are compared with those from other studies of Simmondsia sex ratios, and to the predictions of theories, including adaptive theories, of sexual expression. I conclude that surveys alone cannot distinguish among alternative causal hypotheses, and that experiments and demographic studies will be necessary in general to elucidate variation in sexual expression of plants.