Key Links And Processes For Obtaining Detoxification Seedlings Of Apple Varieties(Lines)

Apple virus disease is one of the important factors affecting the improvement of apple cultivation level in China,and breeding and promoting virus-free seedlings is the most effective technical measure to solve this problem.In order to accelerate the cultivation and promotion of new varieties of apple virus-free seedlings,and promote the standardized production of apple virus-free seedlings,This experiment utilizes some apple varieties(lines)detoxification test tube materials that the research group has obtained,and draws on the experience of domestic and foreign apple virus-free seedling breeding techniques to optimize the key links of virus-free original material breeding,and initially proposes apple scion.Variety virus-free seedling breeding technology system.The main findings obtained are as follows:1.Aiming at the problem of endophytic contamination in the process of tube expansion of apple varieties,the antibacterial effects of ampicillin,carbenicillin and kanamycin were observed in the medium.The results showed that the concentration of the three agents was positively correlated with the antibacterial effect.The low concentration of antibiotics could promote the differentiation of test tube shoots.The concentration of carbenicillin alone should not exceed 200 mg·L-1.The growth quality and antibacterial effect of the test tube seedlings were significantly balanced with Penicillium ampicillin 40 mg·L-1 + carbenicillin 80 mg·L-1,and the bacteria were significantly inhibited within 25 days.Kanamycin is highly toxic and should not be used.2.Optimal cultivation and transplanting conditions of three apple cultivars: rooting tube seedlings with small root callus,more than 4 roots and root length of 3 cm or more,first closed bottle refining seedlings for 5 days,and then bottle-opening seedlings 5-7 d,with grass charcoal: perlite = 5:1 matrix formula,the air humidity is maintained at 90%-100% for the first 10 days after transplanting,the slow seedling is fast,and the survival rate can be above 80%.3.In order to test the detoxification effect of seedlings,the virus was retested by single RT-PCR method for the virus-free tube seedlings planted in the field net.The results showed that the 1-year-old materials stored in the field nets did not carry ASPV.Apple’s main virus such as ASGV and ACLSV.4.In order to understand the growth of transplanted tube seedlings in the field,the growth dynamics of the field were observed.The results showed that the 1-year-old detoxified seedlings grew slowly in April-May,and the fast growing period in June-August,with July being the largest growth period in the whole year.Stagnation began in September and basically stopped after October.Growing.In order to promote the growth of detoxification seedlings,in the early and middle stages of growth,the supply of water and fertilizer should be strengthened to control pests and diseases;in the second half of August,the application of nitrogen fertilizer should be controlled to promote the growth of shoots and buds to avoid the growth of seedlings.5.Seedlings with growth retardation during refining are sprayed with 50-100 mg·L-1 gibberellin(GA3)solution,once every 5-6 d,and continuously sprayed 2-3 times to promote new shoots.Growing.For the 2-year-old test tube detoxification seedlings,in order to increase the number of harvesting ears and reduce the risk of “returning to the child”,measures such as full bud drying,spawning competition tips,and continuous centering of new shoots in the middle and lower parts can be adopted to promote the top new shoots.Growing.