Sex and Gender Dynamics in Jack-in-the-Pulpit, Arisaema Triphyllum (Araceae)
Sex and Gender Dynamics in Jack-in-the-Pulpit, Arisaema Triphyllum (Araceae)
复制标题
讲坛上的杰克的性别和性别动态，Arisaema Triphyllum（天南星科）
作者：
J. L. Doust;P. Cavers
本文报道了三叶天南星（Arisaematriphyllum（L.）Schott（jack-in-the-pulpit）是在1978 - 1979年研究的。有一个范围内的人口性别比，从强烈的女性偏见，强烈的男性偏见，性别二型性方面的身体大小和物候被发现。植物的生物量的比例，发现在生殖和辅助生殖器官的植物，每个性别的确定。具心皮个体的平均总干质量是雄花个体的3.5倍。生殖努力为开花心皮植物干物质的12%，雄花植物的17%，成熟的果心皮植物的44%。所有种群中约10%的生殖植株为雌雄同株。1978年和1979年，在四个地点测量了几个环境因素，这些因素与每个地点的人口性别比例有关。心皮个体在pH值和土壤养分水平较高的遮荫较少的地点占优势。雄花个体集中在较暗的微型点和pH值较低的地区。1978年，我们用267株三叶天南星分株进行了一个相互再植/移植试验，分株来自两个种群性别比不同的地点。雄花、心皮和雌雄异株的植株，即异株，要么在"家"地重新种植，要么移植到"外来"地。1979年和1980年对分株的性别进行了监测。植物性别变化的顺序是无方向性的。植物移植到一个陌生的网站没有保持性别比例特征的家庭网站。对性别变化的显著影响可能归因于植物生长的环境。我们支持的结论是，性别变化是适应性的女性生殖成本大于男性的成本。根据移栽试验的结果，建立了一个简单的模型，在每个地点的生殖植物的性别变化。不同的存活率和性别流动模式可能解释了性别比例的差异。
Eleven populations of Arisaema triphyllum (L.) Schott (jack-in-the-pulpit) were stud- ied in 1978-1979. There was a range of population gender ratios, from strongly female biased to strongly male biased; gender dimorphism with respect to body size and phenology was found. The proportion of a plant's biomass found in reproductive and ancillary reproductive organs was determined for plants of each gender. The mean total dry mass of carpellate individuals was 3.5 times greater than that of staminate plants. Reproductive effort was 12% of dry mass for flowering carpellate plants, 17% for staminate plants, and 44% for mature fruiting carpellate plants. Approximately 10% of the reproductive plants in all populations were monoecious. In 1978 and 1979 several environmental factors were measured at four of the sites, and these were related to population gender ratios at each site. Carpellate individuals were predominant in less- shaded sites where both pH and soil nutrient levels were higher. Staminate individuals were concen- trated in darker microsites and in areas of lower pH. A reciprocal replant/transplant experiment was initiated in 1978, using 267 ramets of Arisaema triphyllum, from two sites with contrasting population gender ratios. Staminate, carpellate, and mon- oecious plants, reciprocally, were either replanted at the "home" site, or transplanted to the "alien" site. The gender of ramets was monitored in 1979 and 1980. The sequence of gender change in plants was nondirectional. Plants transplanted to an alien site did not maintain the gender ratio characteristic of the home site. Highly significant effects on gender change could be attributed to the environment in which plants were grown. We support the conclusion that sex change is adaptive where female reproductive costs are greater than male costs. A simple model of gender change for reproductive plants at each site was constructed, based on the results of the transplant experiment. The differential survivorship and patterns of gender flux provide possible explanations of contrasting gender ratios.