McCarren Sam, Midgley Jeremy J, Coetzee Anina, Johnson Steven D
Department of Biological Sciences, University of Cape Town, 7701 Cape Town, South Africa University of Cape Town Cape Town South Africa.
Department of Conservation Management, Nelson Mandela University, 6530 George, South Africa Nelson Mandela University George South Africa.
PhytoKeys. 2024 Jul 23;244:237-248. doi: 10.3897/phytokeys.244.107288. eCollection 2024.
Pollen transfer efficiency (PTE; the proportion of pollen removed from flowers that reaches conspecific stigmas) is expected to vary with the type of pollinator and flower morphology, and to influence male siring success. Many species in the genus are pollinated by bees (which consume pollen and should thus lower PTE) but during its radiation in the Cape, several independent shifts to both sunbird and long-proboscid fly (LP fly) pollinators, which do not consume pollen have taken place. Improvements in PTE could be one of the factors driving these pollinator shifts. PTE data for 15 species (five for each of the three pollinator types) were collected and compared in relation to type of pollinator and anther exsertion. LP fly- and bird-pollinated species had higher PTE in comparison with bee-pollinated species. Species with inserted anthers had higher PTE than those with exserted anthers. This suggests that sunbirds and LP flies are more efficient pollinators than bees. Additionally, the study suggests that insertion of anthers within the corolla tube can reduce pollen losses.
花粉转移效率（PTE；从花朵上移除并到达同种柱头的花粉比例）预计会因传粉者类型和花的形态而异，并影响雄性的授精成功率。该属中的许多物种由蜜蜂传粉（蜜蜂会消耗花粉，因此会降低PTE），但在其于开普地区的辐射演化过程中，已经发生了几次独立的转变，转向了太阳鸟和长喙蝇（LP蝇）传粉者，它们不会消耗花粉。PTE的提高可能是推动这些传粉者转变的因素之一。收集了15个物种（三种传粉者类型各5个）的PTE数据，并就传粉者类型和花药伸出情况进行了比较。与蜜蜂传粉的物种相比，LP蝇和鸟类传粉的物种具有更高的PTE。花药内藏的物种比花药外露的物种具有更高的PTE。这表明太阳鸟和LP蝇是比蜜蜂更高效的传粉者。此外，该研究表明，将花药插入花冠筒内可以减少花粉损失。
