Community-wide patterns in pollen and ovule production, their ratio (P/O), and other floral traits along an elevation gradient in southwestern China

• Published in: BMC plant biology Vol. 23; no. 1; pp. 1 - 13
• Main Authors: Nepal, Shristhi, Trunschke, Judith, Ren, Zong-Xin, Burgess, Kevin S, Wang, Hong
• Format: Journal Article
• Language: English
• Published: London BioMed Central Ltd 14.09.2023; BioMed Central; BMC
• Subjects: Alpine; Alpine flora; Biodiversity; Breeding success; Cross-pollination; Elevation; Environmental aspects; Environmental changes; Environmental conditions; Evolution; Evolution & development; Floral traits; Flowering; Flowering plants; Flowers; Flowers & plants; Forests; Gametophytes; Genetic aspects; Growth; Height; Insects; Interactions; Mountains; Ovule number; Ovules; Phylogenetics; Phylogeny; Phylogeny (Botany); Physiological aspects; Plant reproduction; Plant reproductive structures; Plant sciences; Plant species; Plants; Plants (botany); Pollen; Pollen number; Pollen-ovule ratio (P/O); Pollination; Pollinators; Reproduction; Spatial variations; Stigmas (botany); Stochasticity; China
• ISSN: 1471-2229; 1471-2229
• DOI: 10.1186/s12870-023-04433-2

As the male and female gametophytes of flowering plants, pollen and ovules largely determine the upper and lower boundaries of plant reproductive success. It is commonly predicted that pollen and ovule number per flower should increase, and pollen-ovule ratio (P/O) per flower should decrease with increasing elevation in response to a more stochastic pollination environment. Here, we aimed to determine the response of pollen number, ovule number, and P/O to other floral traits and elevation gradients for 84 insect-pollinated herbaceous flowering plant species in five sub-alpine and alpine communities (2709 to 3896 m a.s.l.) on Yulong Snow Mountain, southwestern China. Six floral traits, including P/O, floral display area, flower number, tube depth, flower shape, and pollen presentation, were highly correlated with pollen and ovule number per flower. With increasing elevation, pollen number and P/O per flower increased marginally and significantly, respectively; ovule number per individual, flower number per individual, stigma stamen separation, and inflorescence height decreased significantly. However, ovule number per flower and other floral traits (i.e., floral display area, tube depth, stigma height, stamen height, and pollen and P/O per individual) did not change with elevation. We detected significant phylogenetic signals for pollen number, ovule number, and P/O, suggesting that these traits may be highly conserved and with limited response to changing environmental conditions.