McCall Claire, Primack Richard B
Biology Department, Boston University, 02215, Boston, MA, USA.
Oecologia. 1985 Oct;67(3):403-410. doi: 10.1007/BF00384947.
Relationships between pollen loads, resource availability, and fruit and seed production were determined for Lysimachia quadrifolia ramets in two adjacent sites (the scrub site and the open site) in 1982, 1983, and 1984. Pollen loads limited % fruit set and seed production in the open site in 1982 and 1983. Reproduction in the scrub site was resource limited in 1982, as shown by an increase in % fruit set when one-half of the flowers on a ramet were removed prior to fruit initiation. In the scrub site in 1983, pollination of one-half of the flowers on a ramet decreased the % fruit set of the remaining, unpollinated flowers. Fruit production in the same site was limited by pollen in 1984. Addition of nitrogen fertilizer to the scrub site in 1984 had no effect on fruit and seed production. There was more variation in fruit set between sites than between years. There was no trend to greater fruit set or number of seeds/fruit on early flowers compared to late flowers on the same ramet. Correlations between measures of reproduction were positive or insignificant. These results demonstrate year-and site-specific variation in the factors that limit plant reproduction.
1982年、1983年和1984年，对两个相邻地点（灌丛地和开阔地）的四叶排草分株，测定了花粉负载量、资源可利用性与果实和种子产量之间的关系。1982年和1983年，花粉负载量限制了开阔地的坐果率和种子产量。1982年，灌丛地的繁殖受资源限制，这表现为在果实开始形成之前，去除分株上一半的花后，坐果率增加。1983年，在灌丛地，对分株上一半的花进行授粉，会降低其余未授粉花的坐果率。1984年，同一地点的果实产量受花粉限制。1984年，向灌丛地添加氮肥对果实和种子产量没有影响。不同地点之间坐果率的差异大于不同年份之间的差异。同一分株上，早期花的坐果率或果实种子数与晚期花相比，没有更高的趋势。繁殖指标之间的相关性为正或不显著。这些结果表明，限制植物繁殖的因素存在年份和地点特异性差异。
