Cross Compatibility With Different Ploidy Of Hemerocallis Middendorfii

Hemerocallis Middendorfii are Liliaceae families Hemerocallis genus perennial herbs.They are excellent garden and greenbelt flowers and very valuable plants resources.However,the fructification rate and propagation coefficient of Hemerocallis Middendorfii was not high,this phenomenon limited the breeding of new varieties and large-scale propagation of existing varieties.In order to rapid propagation of existing varieties,the cross compatibility between different ploidy Hemerocallis Middendorfii,reasons for the low fructification rate were studied with six diploid,five triploid and seven tetraploid Hemerocallis Middendorfii,from2011.09to2012,10.The main results were descried as follows:1The Fruit-bearing rate and seed germination rate between diploid and diploid, tetraploid and tetraploid was significantly higher than other ploidy combination.The average Fruit-bearing rate between diploids was34.5%,the average seed germination rate was30.2%,and between tetraploids was14.5%and31,69%. Although some others can get some Fruit-bearing number, the seed germination rate was very low. The different ploidy combination of reciprocal cross were some differences, diploid and triploid were the most obvious.2Diploid pollen was the minimum, polar axis length was102.18～119.54μ m, Chek shaft length was35.11～41.27μm. Triploid pollen was132.64～143.31μm and45.78～50.50μm, Tetraploid pollen was126.55～143.45μm, and44.21～53.06μm. Diploid pollen malformation rate was the lowest only3.29%, Tetraploid pollen malformation rate was the highest22.96%.3The Optimum medium for pollen germination was number3:5%sucrose+50mg/1boric acid+2.0%agar;The best acquisition time was8:00in the morning,24℃was the optimum germination temperature. Pollen germination increases by the time, after2hours, the pollen germination rate remained unchanged.4hours was the maximum.The pollination ability of stigma one day before flowering was the strongest, The pollination ability of stigma one day after flowering was the weakest.4The total time for the process of insemination was29-36h. Pollen on the stigma Germination needed1-2h; pollen tube growth in style needed20-22h and growth in the surface of the placenta needed2-4h; Pollen tube got into the embryo sac and the released of sperm taked about2h; sperm-egg fusion needed4-6h; sperm and secondary fusion needed2-4h; the zygote period of dormancy need10-12h; the primary endosperm nucleus have no dormant period.