Study On Key Technologies Of Stem Tip Virus Removal And Tissue Culture Of Main Sweet Potato Varieties In Eastern Hebei Province

In recent years,viral diseases of sweet potato cultivars popularized and planted in eastern Hebei have occurred seriously,especially the starch-type cultivar Lu Xuan1,which was seriously harmed by viral diseases and reduced the yield by more than30%,thus greatly affecting the local sweet potato production.In this paper,the detoxification technology of sweet potato stem tip,detoxification seedling detection technology and rapid propagation technology were studied to provide technical guarantee for the production of virus-free sweet potato seedlings in eastern Hebei Province.The main results of the study are as follows:1.Sterilize sweet potato stem segments with 2% NaClO for 5~15 min.Observed the pollution rate,mortality rate and survival rate of the stem tips.The test results showed that the pollution rate of 9 min,13 min and 11 min with 2% NaClO for Yanshu 25,Luxuan 1 and Beijing 553 respectively was the lowest and the seedling rate was the highest.2.The sweet potato shoot apical meristem was used as the culture object,and the hormone formula suitable for explant growth was screened out.The optimal medium suitable for Yanshu 25,Luxuan 1 and Beijing 553 were MS+1.5 mg/L 6-BA+0.1mg/L IBA,MS+1.0 mg/L 6-BA+0.1 mg/L IBA,MS+1.0 mg/L 6-BA+ 0.5 mg/L IBA,respectively.3.A total of 323 samples were detected,195 of which were virus-free vaccines,and the detoxification rate of SPFMV by serological detection was 63.42%.There were some differences in detoxification effect among different varieties.The detoxification rate of Luxuan1 was 46.39%,that of Yanshu 25 was 88.30%,and that of Beijing 553 was 55.56%.4.The detoxification rate was 37.25% by using the method of stem tip detoxification,while the detoxification rate was 71.43% by stripping the stem tip of sweet potato seedlings after one month of high temperature,and the detoxification effect was obviously better than that without high temperature.5.Through the investigation of plant-related traits among varieties,Lu Xuan1 had the highest plant height,reaching 3.64 cm;Beijing 553 had the second highest plant height,2.56 cm;and Yanshu25 had the lowest plant height,2.27 cm.There was a significant difference in plant height between Luxuan 1 and Yanshu 25,and a significant difference in plant height between Luxuan 1 and Beijing 553.Lu Xuan1 had the longest internode,reaching 0.66 cm;Beijing 553 took the second place,the internode was 0.38 cm;and Yanshu 25 was the shortest,0.33 cm.The internode difference between Luxuan 1 and Yanshu 25 was significant,and that between Luxuan 1 and Beijing 553 reached significant difference.Lu Xuan had the largest number of roots,reaching 5.98;Beijing 553 took the second place,with the number of roots 5.56;and Yanshu 25 had the least number,with 5.25.There was a significant difference in rooting number between Luxuan 1and Yanshu 25.