Studies On Accurate Deternimation Of Anther Dehiscence Level And Analysis On Inherience Of Anther Dehiscence Of Spray Cut Chrysanthemum

Chrysanthemum(Chrysanthemum morifolium)is one of the most important four cut flowers in the world.It is also one of the most popular 10 Chinese traditional cut flowers.It has characterics like being colorful and has various kinds of flower types.It is of great ornamental value.Spray cut chrysanthemum plays a curcial role in inthernatial ornamental industry due to the fact that it is colorful and has uniform blooming period.However,the pollen contamination during the blooming period is very upsetting,for it causes serious allergic responses among pollen-allergic populations aroud.What,s worse,it greatly reduces the ornamental value of spary cut chrysanthemum.Artificial contamation is not practical for cut flower chrysanthemum,so novel anther non-cracking cultivars generatd!by breeding are the only solution to this problem.Therotiecally,the higher the anther dehiscence level is,the more pollens it disperses and the more serious the pollen contamination is.Hence,carrying out researches focusing on the inhericence analysis on anther dehiscence of chrysanthemum is of great significance.Based on previous studies,3 cultivars with different anther dehiscence levels were selected('NA Hongcheng','NA Hongdiandian' and 'Qx-115'),we developed an accurate measuring protocol for anther dehiscence determination.On the other hands,we carried out three cross between 4 parental cultivars with significantly different anther dehiscence levels and obtained adequate F1seedlings.We determind the anther dehiscence levels of the F1seedlings using the protocol we developed and further genetic analysis was conducted.The major results and conclusions are as follows:(1)We developed an accurate measuring protocol for anther dehiscence level;The anther dehiscence level is determined by calculation of quantity of pollen grains in different sections of the liquid area.The pollen grains are wased outside the anther chamber from the cracking point by the liquid droplet.The HD video covers the whole process under the microscope.And microscopic photos are taken before and after the process.This protocol has 3 important features:(2)There's 79 F1 seedlings in total derived from combination 1,among which there's 11 anther non-cracking individuals with a percentage of 13.9%.There's 87 F1 seedlings in total derived from combination 2,among which there's 29 anther non-cracking individuals with a percentage of 33.3%.There's 76 F1 seedlings in total derived from combination 3,among which there's 23 anther non-cracking individuals with a percentage of 30.3%.Most anther dehiscence levels of the F1 individuals lie between their parental's levels and exert a fair tendency of normal distribution.The Rh for the three cross combinations are 26.6%,16.5,and-6.8%respectively.Heterosis and Major Gene Plus Polygene Mixed Genetic Analysis was carried out and it turned out tha the B-3 model applies to both combination 1 and combination 2,and the B-1 model applies to combination 3.The hmg for the three combinations are 98.23%>98.99%and 96.64%.The results indicate that the heterosis and extraparent segregation are common to all the three combinations and it is likely that the paternal genetic effect plays a more important role on the trait of anther dehiscence level.It is highly possible that the anther dehiscence level is a qualitative trait and 2 major genes were detected.The hmg is high and the environmental factors play very little role in the anther dehiscence level of spray cut chrysanthemum.