两种同域分布马先蒿植物花特征的表型选择研究
两种同域分布马先蒿植物花特征的表型选择研究
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DOI：
10.11686/cyxb2019220
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
陈学林
中科院分区：
文献类型：
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作者：
马妍;路宁娜;路广梅;陈学林
马先蒿花冠形态的变异与传粉媒介介导的选择密切相关，但共享传粉媒介、开花时间重叠的相关同域物种如何维持种间分化尚不清楚。本研究连续两年测定了青藏高原东部两个密切相关的物种——甘肃马先蒿和半东马先蒿的花性状。我们通过雌性适合度（种子数）估计了花性状表型选择的强度，并比较了两种马先蒿物种之间的差异。结果表明：（1）两个物种的花性状之间存在显着的相关性。对于P。甘肃甘肃花蜜深度、花大小和花柱长度之间存在显着相关性，并且在不同年份中保持一致。然而，这些花性状与花序数或株高之间的相关性较低。特别是，花蜜深度与其他两个性状不相关。对于P。 semitorta 中，喙长、花柱长度与花大小之间存在显着相关性，但喙长与其他花性状之间的相关性随年份变化显着。 (2)两个物种的花序数和株高的选择显着。此外，对于P.甘肃花的大小、花柱长度和花蜜深度有显着的选择，而P. semitorta 中，花大小和花柱长度的表型选择不太重要，特别是喙长度不影响雌性繁殖成功。这些结果表明：（1）白花花蜜深度、花大小和花柱长度的演化及功能。甘肃可能是高度整合的，花柱长度和花的大小P。 semitorta也可能具有相同的集成。 (2)增加花数、延长花期、增加株高是提高马先蒿雌性适性(制种)的主要手段。 P 的个人。具有较大花朵尺寸和较长花柱的半托塔也往往会提高种子产量。对于P。 semitorta，喙长度可能与花粉传播有关，并由传粉者（即雄性适应性）介导。
The variation in corolla morphology ofPedicularisis closely related to pollinator-mediated selection, but how the related sympatric species, which shar pollinators and overlap in flowering time, maintain the interspecific divergence is still unclear. In this study, we measured the floral traits of two closely related species,Pedicularis kansuensisandPedicularis semitortain the east of the Tibetan Plateau, for two consecutive years. We estimated the intensity of phenotypic selection on floral traits through female fitness (seed number) and compared the difference between the two pedicularis species. The results showed that: (1) There were significant correlations among floral traits of the two species studied. ForP. kansuensis, we found significant correlation between nectar depth, floral size and style length, which were consistent in different years. However, the correlation between these floral traits and inflorescence number or plant height, was low. In particular, nectar depth was not correlated with the other two traits. ForP. semitorta, there was significant correlation between beak length, style length and floral size, but the correlation between beak length and other floral traits changed significantly between years. (2) The selection for inflorescence number and plant height of the two species was significant. In addition, forP. kansuensisthere was significant selection for floral size, style length and nectar depth, while forP. semitorta, the phenotypic selection on floral size and style length was much less significant and in particular beak length did not affect female reproductive success. These results indicate that: (1) The evolution and function of nectar depth, floral size and style length ofP. kansuensismay be highly integrated, and style length and floral size ofP. semitortamay also have the same integration. (2) Increase in flower number, prolongation of the flowering period and increase in plant height are the main means to increase female fitness (seed production) ofPedicularis. Individuals ofP. semitortawith larger floral size and longer styles also tend to have improved seed production. ForP. semitorta, beak length may be related to pollen dispersal, and mediated by pollinators, i.e. male fitness.