Obeso J R
Department of Biología Organismos y Sistemas, Unidad de Ecología, Universidad de Oviedo, E-33005, Oviedo, Spain.
Oecologia. 1993 Apr;93(4):571-575. doi: 10.1007/BF00328967.
Patterns of seed mass variation in the perennial herb Asphodelus albus (Liliaceae) were studied in one population over 3 years (1988-1990) and in three populations during 1989. Plant size, phenology and several components of plant fecundity showed no effect on mean seed mass per plant. Mean seed mass varied among populations and among plants within populations. Significant variation was also found among years and among plants within year, but most of the variation was accounted for by the within-plant component. Withinfruit variation may be as important as between fruits within plant. Fruit position within the plant influenced seed mass, being heavier the seeds at the bottom of the stalk. However, the plants markedly differed in the proportion of the variation accounted for by the position effect. The correlation between seed number per fruit and seed mass showed an interaction with fruit position. Seeds from small broods were heavier than those from large ones, but only in the lower part of the stalk. Decline in seed mass towards the top of the stalk may be attributed to seasonal reduction in resource availability. In addition, the change in the relationship between seed number and mass might be due to changes in the "resolution" of the parent-offspring conflict, also related to nutrient availability.
在1988 - 1990年的3年时间里，对一个种群的多年生草本植物白绵枣儿（百合科）种子质量变化模式进行了研究，并在1989年对三个种群进行了研究。植株大小、物候以及植物繁殖力的几个组成部分对单株种子平均质量没有影响。平均种子质量在种群之间以及种群内的植株之间存在差异。在年份之间以及年内植株之间也发现了显著差异，但大部分差异是由植株内部因素造成的。果实内部的差异可能与植株内果实之间的差异同样重要。植株内果实的位置影响种子质量，茎秆底部的种子较重。然而，植株在位置效应所造成的差异比例上明显不同。每个果实的种子数量与种子质量之间的相关性显示出与果实位置的相互作用。来自小果穗的种子比大果穗的种子重，但仅在茎秆下部如此。种子质量向茎秆顶部下降可能归因于资源可利用性的季节性降低。此外，种子数量与质量之间关系的变化可能是由于亲子冲突“分辨率”的变化，这也与养分可利用性有关。
