Effects of pollen reward removal on fecundity in a self-incompatible hermaphrodite plant
Effects of pollen reward removal on fecundity in a self-incompatible hermaphrodite plant
复制标题
DOI：
10.1111/j.1438-8677.2011.00445.x
复制
发表时间：
2011-05-01
期刊：
影响因子：
3.9
通讯作者：
Johnson, S. D.
中科院分区：
文献类型：
--
作者：
Duffy, K. J.;Johnson, S. D.
雌雄同体植物的花粉常被访花动物利用。虽然花粉生产对植物雄性适合度有明显的好处，但它对植物雌性适合度的影响，特别是在自交不亲和的雌雄同体物种中，不太确定。花粉生产可以提高种子生产，虽然增加传粉吸引力，或减少它，如果胚珠被打折的沉积自花粉，可以发生在物种与迟效自交不亲和。为了测试花粉奖励规定对女性健身的影响，我们人工阉割花的肉质芦荟斑（Asphodelaceae），它有一个迟发性自交不亲和系统，在其花期的过程中的两个人口。本种的花被太阳鸟（花蜜）和本地蜜蜂（花粉和花蜜）访问。我们测量了去雄和非去雄植株的访花率、拒花率、柱头和果实上的花粉沉积以及结实率。我们发现，去雄植物的花朵遭受蜜蜂减少访问和增加拒绝（到达没有访问），但不是太阳鸟;有较少的花粉粒沉积在柱头上，并显示出整体下降，在坐果和种子集。种子败育率，然而，大大减少了去雄花。这项研究表明，花粉奖励可以是重要的种子集，即使在自交不亲和的植物，已被假定为依赖花蜜奖励传粉者的吸引力。种子败育，但是，增加了花粉生产，结果突出了选择的复杂性，在雌雄同体的花花粉生产。
The pollen of hermaphrodite plants is often utilised by flower-visiting animals. While pollen production has obvious benefits for plant male fitness, its consequences for plant female fitness, especially in self-incompatible hermaphrodite species, are less certain. Pollen production could either enhance seed production though increased pollinator attraction, or reduce it if ovules are discounted by deposition of self pollen, as can occur in species with late-acting self-incompatibility. To test the effects of pollen reward provision on female fitness, we artificially emasculated flowers in two populations of the succulent Aloe maculata (Asphodelaceae), which has a late-acting self-incompatibility system, over the course of its flowering period. Flowers of this species are visited by sunbirds (for nectar) and native bees (for pollen and nectar). We measured floral visitation rates, floral rejection rates, pollen deposition on stigmas and fruit and seed set in both emasculated and non-emasculated plants. We found that flowers of emasculated plants suffered reduced visitation and increased rejection (arrival without visitation) by bees, but not by sunbirds; had fewer pollen grains deposited on stigmas and showed an overall decrease in fruit set and seed set. Rates of seed abortion were, however, greatly reduced in emasculated flowers. This study shows that pollen rewards can be important for seed set, even in self-incompatible plants, which have been assumed to rely on nectar rewards for pollinator attraction. Seed abortion was, however, increased by pollen production, a result that highlights the complexity of selection on pollen production in hermaphrodite flowers.