甘薯脱毒及种薯(苗)繁育技术研究OA

China is the largest sweet potato producer in the world.However,the development of the sweet potato industry is severely constrain-ed by viral diseases.The establishment of a universal virus-free tissue culture system,a highly sensitive detection system,and an efficient seed potato(seedling)breeding system are of great significance for the development of the sweet potato industry.A total of 12 main cultivars were subjected to shoot-tip virus elimination treatment using a universal tissue culture system MS+2 mg/L NAA+1.0 mg/L 6-BA,with regeneration rates of over 58%for most cultivars.Specific primers for five viruses,namely SPFMV,SPCSV,SPLV,SPCFV and SPVG,were obtained.The detection limits of these primers for the viruses were 10-6,10-1,10-4,10-3 and 10-3,respectively,indicating high sensitivity.Virus-free lines were selected,and excellent virus-free strains Gan 12 and Fenshu 2-2 were obtained.A three-tier breeding system for virus-free seed po-tatoes was established,including tissue culture seedlings(first tier),temperature-controlled greenhouse substrate seedlings(second tier)and field seedlings(third tier)for seed production.In addition,a comparison trial was conducted to evaluate the washing rate of seedlings(with roots and without roots),as well as a dual-factor experiment to assess transplanting methods(with roots and without roots)and the number of transplanted seedlings per hole(1-3 plants).Results showed that the treatment without roots significantly increased the washing rate of seed-lings.There were no significant differences in plant height,stem thickness,and internode number among groups with different numbers of transplanted seedlings(1-3 plants)during the early stage of seedling growth.The treatment with roots had advantages in early growth,but did not significantly affect the survival rate or the final result of seedling growth.Therefore,this study was beneficial for the prevention and control of sweet potato viral diseases,the promotion of virus-free seed potatoes,and the reduction of seedling production costs.