Study On Pollination Ecology Of Ampelopsis Sinica(Miq.) W. T. Wang,Cayratia Japonica(Thunb.) Gagnep.and Rubia Cordifolia Linn. On The Mount Zhen In Yantai

Ampelopsis sinica(Miq.)W.T.Wang and Cayratia japonica(Thunb.)Gagnep.belong to vines of the family Vitaceae,and Rubia cordifolia Linn.belongs to perennial grass climbing vines of the family Rubiaceae,all these three plants are trailing plants.Vitaceae is assisted by its unique climbing stems,Rubia cordifolia climbs by inverted prickles,the fruits of Ampelopsis sinica(Miq.)W.T.Wang are blue-purple,and the fruits of Cayratia japonica(Thunb.)Gagnep.and Rubia cordifolia Linn.are black-purple.These three plants are not only used as Chinese medicinal materials,but also have ornamental value.Because of its strong adaptability,resistance to barrenness,heavy metal resistance ability and the characteristic of creeping growth,trailing plants plays a vital role in slope protection and soil stabilization,water conservancy management and environmental afforestation.Researching on the pollination ecology among three plants could provide references for the soil remediation,revegetation on hard slope and riming-area.In this study,we selected Mount Zhen which is in Zhifu District,Yantai City as the observation site.The flowering phenology,pollen viability,stigma activity,breeding system,species and behavior of visitors of Ampelopsis sinica(Miq.)W.T.Wang,Cayratia japonica(Thunb.)Gagnep.and Rubia cordifolia Linn.were carried out through positioning observation,microscopic observation,TTC,Benzidine-H₂O₂and activity determination analysis in this area.The main results are summarized as follows:The flowering period of Ampelopsis sinica(Miq.)W.T.Wang was from late May to mid-to-late July,and the flowering period of Cayratia japonica(Thunb.)Gagnep.lasted from mid-to-late June to mid-to-late October and the flowering period of Rubia cordifolia Linn.was from early July to late September.The flowering period of Cayratia japonica(Thunb.)Gagnep.was about 4 months,which is the longest among the three plants.It's worth to be mentioned that the precipitation in January-August2020 was much higher than that in January-August 2019.And the temperature in 2020was also be slightly higher than that of the previous year.Therefore observations have shown that the single-flower flowering period in 2020 is slightly earlier,and the flowering period of population has not been significantly affected.Pollen vitality was different in different periods due to different plants.On the whole,the pollen vitality of the three plants was the strongest when they first bloom,and then gradually decreases.The pollen vitality and stigma receptivity basically reach the maximum vigor at the same period.Gradient temperature germination test proves that the germination rate of Ampelopsis sinica(Miq.)W.T.Wang,Cayratia japonica(Thunb.)Gagnep.and Rubia cordifolia Linn.reached the peak value at 25?.The stigma of the three plants was the same category,all of which are dry stigmas,and the stigma receptivity was basically around the period of maximum pollen vitality.According to the result of P/O,OCI and bagged test,it is verified that the three-plants'breeding systems were all facultative self-pollination,which requires flower visitors to assist in pollination.The most frequent flower visitors were Diptera,then Hymenoptera,Lepidoptera and Coleoptera.Occasionally,the visitors of Cayratia japonica(Thunb.)Gagnep was slightly different with the number of Ampelopsis sinica(Miq.)W.T.Wang,Diptera accounts for the largest proportion of flower-visiting insects,followed by Lepidoptera and Hemiptera.The most common flower visitors of Rubia cordifolia Linn.were Apis mellifera of Hymenoptera and Episyrphus balteatus of Diptera,followed by Lepidoptera and Coleoptera.Beetles and flies and ants of the order of Diptera.Flower-visiting bees carry pollen on their bodies.The behavior of flower visitors was affected by temperature and light obviously.The frequency of flower-visiting peaked over time.Peak values of Ampelopsis sinica(Miq.)W.T.Wang and Cayratia japonica(Thunb.)Gagnep were at 10:00-11:00 during the day,while the peak value of Rubia cordifolia Linn was at 11:00-12:00.It is observed that compared with last year,not merely the precipitation and temperature but the types and number of flower visitors increased in 2020.Therefore,precipitation and temperature have an impact on the biodiversity of flower visitors.