We conducted univariate and multivariate analyses to compare floral morphological traits and analyzed floral reward (nectar and pollen) quantity and quality between flowers of wild and domesticated Cucurbita taxa. Staminate and pistillate flowers of all three taxa were video recorded, and visitation and behavior of floral visitors were registered and analyzed.
Most floral morphological characteristics of flowers of domesticated taxa were larger in both staminate and pistillate flowers. Staminate and pistillate flowers presented distinct correlations between floral traits and integration indices between domesticated and wild species. Additionally, pollen quantity and protein to lipid ratio were greater in domesticated species. Cucurbit pollen specialists, Eucera spp., had the highest probability of visit for all Cucurbita taxa.
We provide evidence that floral traits of domesticated and wild Cucurbita species experienced different selection pressures. Domesticated Cucurbita species may have more resources invested towards floral traits, thereby increasing attractiveness to pollinators and potentially plant reproductive success. Wild ancestor plant populations should be conserved in their centers of origin to preserve plant-pollinator interactions.
方法:我们进行了单变量和多变量分析,以比较野生和驯化葫芦类群花的花形态性状,并分析花奖赏(花蜜和花粉)的数量和质量。记录了所有三个分类群的雄花和雌蕊花的视频,并对花卉参观者的参观和行为进行了登记和分析。
结果:驯化类群花的大多数花形态特征在雄花和雌花中均较大。雄花和雌蕊花在驯化和野生物种之间的花性状与整合指数之间表现出明显的相关性。此外,驯化物种的花粉数量和蛋白质与脂肪比更高。瓜类花粉专家,Euceraspp.,所有南瓜类群的访问概率最高。
结论:我们提供的证据表明,驯化和野生葫芦的花卉性状经历了不同的选择压力。驯化的南瓜物种可能有更多的资源投资于花卉性状,从而增加对传粉者的吸引力和潜在的植物繁殖成功。野生祖先植物种群应保存在其起源中心,以保持植物与传粉者的相互作用。