Optimization Of High-efficiency Isolated Microspore Culture System In Non-heading Chinese Cabbage

Microspore culture technology refers to the use of cell totipotent combined with modem cell culture techniques to make free microspores change their gametophyte developmental processes through external stimuli,transform into spores and eventually develop into plants.Compared to the traditional method of obtaining a pure line by selfing,a DH population can be obtained in only 1-2 years.In this study,the influencing factors of isolated microspore culture of non-heading Chinese cabbage and the identification of microspore plant culture and ploidy were studied in order to improve the efficiency of isolated microspore embryogenesis and simplify the microspore plant cultivation techniques,thereby improving the non-heading Chinese cabbage DH Plants gain efficiency and promote the development of new varieties.The main findings are as follows:(1)The effects of genotypes on embryogenesis of non-heading Chinese cabbage were studied using 12 non-heading Chinese cabbage commercial varieties.Only 12 out of 12 varieties had embryoid bodies and the embryo emergence rate reached 83.3%.The highest rate of embryos in the 'Kuaicai' average embryos have 13.62 embryos/buds;and'Naibaicai' varieties have only 0.12 embryos/buds;F1 and high self-transparent parent embryo rate and no significant difference.(2)According to the situation of embryos,three varieties with different embryogenesis rates(Kuaicai,Erzhuangbai,Qinggengcai)were selected to investigate the effects of hormone 6-BA,trace elements of boron,flowering time,and activated carbon on the embryogenesis rate of microspores.When the concentration of 6-BA in 0-0.06mg/L 6-BA will promote the embryogenesis rate of microspores,but when the concentration of 6-BA is greater than 0.06mg/L,6-BA will have an embryogenic rate of microspores.Inhibitory effect;the highest efficiency of embryo emergence rate occurs in the early flowering stage or flowering stage;boron can promote the occurrence of microspore embryogenesis,but the effects on different genotypes are different;the effect of activated carbon is mainly in the first four days of the effect Larger,but on the sixth day,the role of activated carbon basically failed.(3)The improved medium(normal MS medium+0.02mg/L NAA+0.2mg/L 6-BA+activated carbon)was selected from the three kinds of embryoid bodies of 'Kuaicai','Erzhuangbai','Qinggengcai'.1mg/L+3%sucrose and 1.2%agar concentration can induce the formation of microspore embryoid bodies in a simple and effective manner.The highest'Erzhuangbai' white variety up to 67.5%,and the 'Kuaicai' minimum is also 37.5%.(4)The ploidy was used to identify the plants using morphology and flow cytometry.It was found that the haploid plants were weak,the leaves were smaller and had shrunken,the floral twigs were smaller,they were not full,they had automatic withering,the number of buds was small,and the stems were thin and small.Little or no pollen.In the identified 26 non-heading Chinese cabbage sporulation plants,there were 5 double haploid plants and 21 haploid plants.No chimera was found,and the cultivar 'Erzhuangbai' had a double rate of 20%;the variety 'Kuaicai' was added.The magnification was 33.3%;the cultivar'Qinggengcai' was 0%.