Aims Most flowering plants engage in mutualisms with animals to move pollen between individuals,and it is expected that pollinators play an essential role in the evolution of selfing,yet few studies have deter-mined h...Aims Most flowering plants engage in mutualisms with animals to move pollen between individuals,and it is expected that pollinators play an essential role in the evolution of selfing,yet few studies have deter-mined how distinct pollinator types affect a plant’s mating system and reproductive success differentially.We investigated the effect of two different pollinators on the reproductive success of Incarvillea sinensis,an annual with showy,insect-pollinated,one-day flowers.Methods We marked flowers after a single visit from both pollinator species(Bombus patagiatus and Amegilla quadrifasciata)and calculated the number of pollen grains deposited on the stigma and pollen left in the anthers,the fruit and seed set,the outcrossing rate and the cor-relations of paternity.Important Findings There was no significant difference in the number of pollen grains deposited on the stigma,or in the seed and fruit set between the two pollinators in both years.The mean number of pollen grains removed by B.patagiatus was significantly higher than that removed by A.quadrifasciata.The outcrossing rate of flowers pollinated by B.patagiatus was significantly higher than that of flowers pollinated by A.quadrifasciata.The correlation of paternity of flowers pollinated by B.patagiatus was significantly lower than that of flowers polli-nated by A.quadrifasciata.For I.sinensis,B.patagiatus may exhibit larger pollen wastage,thus reducing the male reproductive success of the plant,but it causes higher female reproductive success because of its higher outcrossing rate and the lower correlation of paternity.Our findings highlighted that different animal pollinators could indeed cause differential mating systems and reproductive success.展开更多
Floral sexual organ(stamen and pistil)movements are selective adaptations that have different functions in male-female reproduction and the evolution of flowering plants.However,the significance of stamen movements in...Floral sexual organ(stamen and pistil)movements are selective adaptations that have different functions in male-female reproduction and the evolution of flowering plants.However,the significance of stamen movements in the spatialetemporal function and separation of male and female organs has not been experimentally determined in species exhibiting floral temporal closure.The current study investigated the role of slow stamen(group-by-group)movement in male-female sexual function,and the effect of stamen movement on pollen removal,male-male and male-female interference,and mating patterns of Geranium pratense,a plant with temporal floral closure.This species uses stamen group-by-group movement and therefore anther-stigma spatialetemporal separation.Spatial separation(two whorls of stamen and pistil length)was shown to be stronger than temporal separation.We found that stamen movements to the center of the flower increase pollen removal,and the most common pollinators visited more frequently and for longer durations during the male floral stage than during the female floral stage.Petal movements increased both self-pollen deposition rate and sexual interference in G.pratense.The fruit and seed set of naturally and outcrossed pollinated flowers were more prolific than those of selfpollinated flowers.Group-by-group stamen movement,dehiscence of stamens,pistil movement,and male-female spatialetemporal functional separation of G.pratense before floral temporal closure may prevent male-female and stamen-stamen interference and pollen discounting,and may increase pollen removal and cross-pollination.展开更多
The Beibu Gulf is a semi-enclosed gulf in the northwest of the South China Sea.We palynologically analyzed 306 surface sediment samples from the eastern Beibu Gulf to improve bioclimatic interpretation of fossil polle...The Beibu Gulf is a semi-enclosed gulf in the northwest of the South China Sea.We palynologically analyzed 306 surface sediment samples from the eastern Beibu Gulf to improve bioclimatic interpretation of fossil pollen records there.Surface pollen assemblages could be classified into five pollen regions based on the distributions of total,arboreal,herbaceous and fern pollen concentrations.Four high-concentration and three low-concentration subregions could be distinguished within these regions.The distribution patterns of surface pollen assemblages were consistent with those of grain sizes of surface sediments.Sediments from regions with high pollen concentrations were very fine and fine silts (>7.0,<0.008 mm),whereas those with low pollen concentrations were fine sand (<3.5,>0.088 mm).Sedimentary heterogeneity of surface pollen assemblages was closely related to pollen source,transportation and sedimentation controlled by ocean currents,tides and waves,and oceanic bottom topography.Fern spores exhibited higher percentages along the east margins of the region,while arboreal types like Pinus increased in concentration towards the center.Herbaceous pollen appeared in high percentages around seacoasts near their source areas.Dacrydium and mangrove pollen were distributed near their source regions at low percentages.We discuss the sediment dynamic environments in the eastern Beibu Gulf based on surface pollen distributions.The estuary region is an important access to the sea basin and a depositional site for terrestrial pollen grains.Coastal regions can accumulate pollen due to the back-and-forth movements of tides there.Although ocean currents on a gulf scale tend to spread pollen grains,the interaction of multiple currents could lead to pollen accumulation and deposition.Low surface pollen concentrations in the northeast shallow-water regions of the eastern Beibu Gulf could be attributed to repeated washing and sediment floatation caused by severe wave activities during the summer.Strong tides in Qiongzhou Strait f展开更多
基金This work was supported by the National Natural Science Foundation of China(41371073 and 41671040).
文摘Aims Most flowering plants engage in mutualisms with animals to move pollen between individuals,and it is expected that pollinators play an essential role in the evolution of selfing,yet few studies have deter-mined how distinct pollinator types affect a plant’s mating system and reproductive success differentially.We investigated the effect of two different pollinators on the reproductive success of Incarvillea sinensis,an annual with showy,insect-pollinated,one-day flowers.Methods We marked flowers after a single visit from both pollinator species(Bombus patagiatus and Amegilla quadrifasciata)and calculated the number of pollen grains deposited on the stigma and pollen left in the anthers,the fruit and seed set,the outcrossing rate and the cor-relations of paternity.Important Findings There was no significant difference in the number of pollen grains deposited on the stigma,or in the seed and fruit set between the two pollinators in both years.The mean number of pollen grains removed by B.patagiatus was significantly higher than that removed by A.quadrifasciata.The outcrossing rate of flowers pollinated by B.patagiatus was significantly higher than that of flowers pollinated by A.quadrifasciata.The correlation of paternity of flowers pollinated by B.patagiatus was significantly lower than that of flowers polli-nated by A.quadrifasciata.For I.sinensis,B.patagiatus may exhibit larger pollen wastage,thus reducing the male reproductive success of the plant,but it causes higher female reproductive success because of its higher outcrossing rate and the lower correlation of paternity.Our findings highlighted that different animal pollinators could indeed cause differential mating systems and reproductive success.
基金the High-level Personnel Training Program of the Xinjiang Uygur Autonomous Region(QN2016BS0597)。
文摘Floral sexual organ(stamen and pistil)movements are selective adaptations that have different functions in male-female reproduction and the evolution of flowering plants.However,the significance of stamen movements in the spatialetemporal function and separation of male and female organs has not been experimentally determined in species exhibiting floral temporal closure.The current study investigated the role of slow stamen(group-by-group)movement in male-female sexual function,and the effect of stamen movement on pollen removal,male-male and male-female interference,and mating patterns of Geranium pratense,a plant with temporal floral closure.This species uses stamen group-by-group movement and therefore anther-stigma spatialetemporal separation.Spatial separation(two whorls of stamen and pistil length)was shown to be stronger than temporal separation.We found that stamen movements to the center of the flower increase pollen removal,and the most common pollinators visited more frequently and for longer durations during the male floral stage than during the female floral stage.Petal movements increased both self-pollen deposition rate and sexual interference in G.pratense.The fruit and seed set of naturally and outcrossed pollinated flowers were more prolific than those of selfpollinated flowers.Group-by-group stamen movement,dehiscence of stamens,pistil movement,and male-female spatialetemporal functional separation of G.pratense before floral temporal closure may prevent male-female and stamen-stamen interference and pollen discounting,and may increase pollen removal and cross-pollination.
基金supported by the Chinese Offshore Investigation and Assessment Project (908-01-ZH2)the National Marine Public Welfare Research Project (200805063-3)
文摘The Beibu Gulf is a semi-enclosed gulf in the northwest of the South China Sea.We palynologically analyzed 306 surface sediment samples from the eastern Beibu Gulf to improve bioclimatic interpretation of fossil pollen records there.Surface pollen assemblages could be classified into five pollen regions based on the distributions of total,arboreal,herbaceous and fern pollen concentrations.Four high-concentration and three low-concentration subregions could be distinguished within these regions.The distribution patterns of surface pollen assemblages were consistent with those of grain sizes of surface sediments.Sediments from regions with high pollen concentrations were very fine and fine silts (>7.0,<0.008 mm),whereas those with low pollen concentrations were fine sand (<3.5,>0.088 mm).Sedimentary heterogeneity of surface pollen assemblages was closely related to pollen source,transportation and sedimentation controlled by ocean currents,tides and waves,and oceanic bottom topography.Fern spores exhibited higher percentages along the east margins of the region,while arboreal types like Pinus increased in concentration towards the center.Herbaceous pollen appeared in high percentages around seacoasts near their source areas.Dacrydium and mangrove pollen were distributed near their source regions at low percentages.We discuss the sediment dynamic environments in the eastern Beibu Gulf based on surface pollen distributions.The estuary region is an important access to the sea basin and a depositional site for terrestrial pollen grains.Coastal regions can accumulate pollen due to the back-and-forth movements of tides there.Although ocean currents on a gulf scale tend to spread pollen grains,the interaction of multiple currents could lead to pollen accumulation and deposition.Low surface pollen concentrations in the northeast shallow-water regions of the eastern Beibu Gulf could be attributed to repeated washing and sediment floatation caused by severe wave activities during the summer.Strong tides in Qiongzhou Strait f
