| Pedicularis species provide ideal materials to study flower evolution, pollination biology, and plant speciation for their substantial variation in floral design. Hengduanshan Mountain, locating in Southwest of China, is regarded as the centre of origin and evolution of genus Pedicularis, where species with all corolla types are present. Pedicularis is a young group, and displays rapid floral variation from a narrow genetic basis. The current pattern of flower variation in Pedicularis does not correspond with their single and exclusive bumblebee pollinator. New insight is needed to understand the relationship between flower evolution and pollination adaptation. In this study, we had chosen many Pedicularis species from Hengduanshan Mountain to focus on the questions as following: (1) the current pattern of floral variation in morphological and quantitative characteristics; (2) the role of pollinator in flower differentiation; and (3) the variation in reproductive success for species with different corolla type.Stigma morphology in Pedicularis and its role in pollination have not been evaluated. This paper reports for the first time the relationship between stigma morphology and other aspects of floral design. 17 species of Pedicularis representing all the different types of corolla structure in the genus were studied in the field and laboratory. Results indicate that the stigmatic surface morphology of Pedicularis species is related to the type of corolla structure occurring in the species. Pollination studies in 8 Pedicularis species demonstrated adaptation between stigmatic surface morphology and other aspects of floral biology. Species with larger, more corrugated stigmatic surfaces always possess a subsidiary construction ("tooth" or "beak") on the galea. In addition, they have relatively longer flower tubes, higher stigmatic pollen loads, bigger pollen size and a shorter blooming period for individual flowers. Finally, the author discusses the evolutionary significance of floral design in genus Pedicularis.Current patterns of floral design in Pedicularis must have undergone an evolutionary process of interacting among components of floral traits, and then formed internal relationships among these traits. To detect such correlations, which may provide insight to understand flower evolution, 40 Pedicularis speciesrepresenting all corolla types of the genus were studied. Results show that, interspecifically, pollen size correlates negatively with pollen number, but positively with pistil length. This suggests that plants evolve an optimal pollen size, which balances the advantages of large pollen size for gametophytic competition against the fecundity disadvantages of fewer pollen grains. In contrast to sex allocation theory, this study doesn't find a trade-off, but an interspecific positive correlation between pollen and ovule number. This is consistent with the hypothesis that genetic variation for resource acquisition may in part be responsible for the lack of negative correlation between male and female function. Pollen-ovule ratios do not differ among both different corolla types and taxonomic grexes, and then suggest that pollen-ovule ratio should be parallel evolution. It is also suggested that the correlations between pollen-ovule ratio and pollen size (-), and ovule size (+) should be accounted for in terms of sex allocation theory.During this project, no other effective pollinators except bumblebees and no species-specific pollinator have been observed for all kinds of Pedicularis species. Pollen grains are transferred by bumblebees foraging for nectars and/or pollen. Pollen grains then deposit on their body, and soon are groomed and collected to the pollen baskets. However, in a certain situation where pollen deposited is not accessible for grooming, but exactly share to stigma, which is protruding from the tip of the corolla beak. Each of the species has such a "pollination area" on the body of their pollinators. Bumblebees exhibit high level of flower constant foraging beha...
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