The Study On Pollination Biology Of Goodyera Foliosa (Orchidaceae)

In order to understand the pollination mechanism of Goodyera foliosa, the general situation of experimental site, floral phenology, flower morphological features,pollen viability and stigma receptivity, artificial pollination, volatile components,insect pollination behavior, color and smell confirmatory experiment, seed vigor,asepsis seeding were studied by field observation and laboratory analysis. The results were as follows.There were 107 species including 47 arbors, 20 shrubs, 27 herbs, 9 ferns, 4vines, with 10 co-blooming plants including 7 herbs, only one orchid Hetaeria cristata in the experiment area.The population florescence, single inflorescence florescence, single flower florescence was 26 days, 14.6 days, 9.4 days, respectively. G. foliosa had yellow labellum, white or white with brown sepal. There was no reward in the flower. The length of inflorescence, labellum, labellum breadth, gynostemium, flower opening,breadth was 112.80(±1.10) mm, 7.51(±0.42) mm, was 4.27(±0.23) mm, 3.05(±0.15) mm, 3.12(±0.21) mm, 3.03(±0.17) mm.The pollen was active at the first day after flowering(60%), while stigma had receptivity at the second day after flowering, and all of them reached peak at the fifth day. The results showed artificial pollination in 5 days later after blooming was best.The natural seed set rate was 43.3%, while emasculation by bagging or not emasculation by bagging could not fruit setting. The seed setting rate of illegitimate pollination, cross pollination within plant or plants was 93.3%, 95.0% and 96.7%,respectively. The results showed that G. foliosa no self-pollination and apomixis.There were 4 flower-invisting insects including Apis cerana, Bombus diversus,Paper wasp, Chilasa epicydes, while A.cerana was the unique effective pollinator.The length and breadth of its head was 3.58(±0.18) mm and 3.24(±0.12) mm, and was less than the flower opening length and breadth. The bee could make its trophi and head into flower, while the head could kick operculum and the pollen exposed when it turned back. In this process, the pollen was clinged by trophi. Bee visitedanother flower with pollen would make pollen into the stigma to accomplish pollination.1-Octen-3-ol, 3-Octanol and N,N-dimethylformamide was major volatile components in flowers of G foliosa. In the validation experiments, the bees visited yellow cloth highly, followed by white, pink, at least was yellow. That showed yellow had relatively strong attraction. The bee visited 3- octanol cotton frequently, followed by three reagent mixed solution treated cotton, while the least was only N, N-dimethyl formamide processing cotton. That showed 3- octanol to bee had a certain appeal.2 months after pollination, fruit seed vigor was highest while 1 month was lowest, different methods had no significant effect on seed vigor, so 2 months after pollination for asepsis seeding was best. The germination rate of natural seed on the MS culture medium reached 85.6%, and the seed expanded after a month,differentiated after four months, rooted after six months.Therefore, it was suggested that G. foliosa had self-compatible capability, but not automatic self-cross phenomenon. It must dependent on pollinator A. cerana, and the flower color and floral scent were main factors for attracting pollinators.