Studies On Flower Morphology And Pollen Characteristics Of Acer Genus

This article uses Acer rubrum,Acer truncatum,Acer pseudosieboldianum,Acer tegmentosum,Acer ukurunduense,Acer ginnala,Acer negundo,Acer negundo cv.Aurea,Acer negundo cv.Flamingo in Northeast China as the research object.By observed their flowering phenology,flower morphology and pollen morphology,in order to learn more about the pollination biology of Acer trees in Shenyang.Research their pollen germination conditions and storage conditions,found the best germination conditions for pollen.And do some basic research for enrich Chinese Acer genus resources and cultivate new varieties.The results are as following:1.The flowering phase of 9 Acer trees was from April to June in Shenyang,group flowering phase is 20³0 days.Acer rubrum,Acer negundo,Acer negundo cv.Aurea and Acer negundo cv.Flamingo are dioecious,5 stamens.Acer truncatum,Acer pseudosieboldianum,Acer tegmentosum,Acer ukurunduense,Acer ginnala are androgynous,8 stamens.The other Acer trees have disks,5 sepals and 5 petals,except Acer negundo,Acer negundo cv.Aurea and Acer negundo cv.Flamingo,sepals has the same color as petals.They has 2 style.In the same Acer trees,flowers of different sexes also have different morphology characteristics.The male flowers usually has bigger sepals,petals and thrum.Stamens of bisexual flower can not fully developed and spread out pollen.Acer rubrum,Acer negundo,Acer negundo cv.Aurea and Acer negundo cv.Flamingo had the typical characteristics of wind pollination.Acer ukurunduense,Acer pseudosieboldianum,Acer tegmentosum,Acer truncatum and Acer ginnala had the typical characteristics of insect pollination.2.The pollen of these Acer trees are all prolate,it is oval in equatorial and three-lobed circular in polar viewed.Polar axis length was 29.90⁴7.91?m,equatorial axis length was14.76²3.98?m.The aperture of them are all 3-colpate except Acer ukurunduense.Acer ukurunduense is 3-colporate,reaching both poles.The exine sculpture of Acer negundo,Acer negundo cv.Aurea and Acer negundo cv.Flamingo are reticuler,the others are striate,the striate paralled each other or not.The size of areole and the distance between fossa are all different.8Acer species were divided into 3 groups according to the results of the Cluster Analysis.The first group includes Acer negundo,Acer negundo cv.Aurea,Acer negundo cv.Flamingo,Acer pseudosieboldianum and Acer ukurunduense.The second group include Acer rubrum and Acer truncatum.The third group just has Acer tegmentosum.3.The result showed that Acer rubrum pollen in the culture medium at 28?culture temperature with 75g/L sucrose and 150mg/L boric acid had a germination rate of 81.95%;Acer truncatum pollen in the culture medium at 25?culture temperature with 100g/L sucrose and 250mg/L boric acid had a germination rate of 66.7%;Acer negundo pollen in the culture medium at 28?culture temperature with 25g/L sucrose and 350mg/L boric acid had a germination rate of 88.37%.Acer negundo cv.Aurea pollen in the culture medium at 28?culture temperature with 75g/L sucrose and 350mg/L boric acid had a germination rate of93.34%.Acer negundo cv.Flamingo pollen in the culture medium at 28?culture temperature with 75g/L sucrose and 150mg/L boric acid had a germination rate of 90.31%.4.The study found TTC method and I₂-IK method can not stain pollen,but Peroxidase method and Methylene blue method is very effective.Study found that the lower the storage temperature,the better the preservation of pollen viability.On-80?storage condition,their germination rate can reach 40%or more.