The Main Viral Disease Identification Of Tillering Onion And Technology System Establishment Of Rapid Propagation By Detoxification

In order to establish a virus-free and efficient technology system for rapid propagation of tillering onion,a series of experiments were carried out with local tillering onion varieties in Jilin Province as materials,including detection and identification of main virus diseases of tillering onion,virus-free shoot tip,induction of test tube bulb,proliferation of micro bulb disc,rooting culture,transplanting and domestication,and field comparative test of virus-free seed ball and production seed The industrial production of high-quality seedlings provides a theoretical basis.The main results are as follows:1.The infection rate of OVDY was 58.00%in Halahai town of Nongan county and 52.00%in Huaide town of Gongzhuling City by ELISA;the 403 bp fragment was amplified by RT-PCR,and compared with the OVDY sequence retrieved from NCBI,the similarity was 94%;the phylogenetic tree showed that OVDY-JL and O.70 were in the same branch and had the closest relationship.2.The results showed that the best sterilization time of tillering onion shoot tip was 60 s with75%ethanol and 13 min with 1%Na Cl O;the best start-up medium of tillering onion shoot tip was MS+NAA 0.1 mg/L,and the seedling rate was 87.50%;when combined with heat treatment and shoot tip culture,the bulbs were peeled 0.5～0.8 after heat treatment at 85℃for 10 min,the virus-free rate of shoot tip was 91.11%,and the virus-free rate was 97.78%.When the concentration of ribavirin was 5 mg/L,the virus-free rate of shoot tip was 92.22%,and the virus-free rate was 81.11%.3.When the concentration of sucrose was 60 mg/L,it was the best for bulb induction of tillering onion in vitro;the soft sugar could replace sucrose as the carbon source of the medium for bulb induction of tillering onion in vitro;the best medium for bulb disc proliferation of tillering onion was MS+6-BA 0.4 mg/L+NAA 0.1 mg/L,and the average proliferation coefficient was16.05;in order to shorten the breeding period,it is most suitable to use the tube bulbs cultured for6 weeks in the experiment of micro bulb disk proliferation;the results showed that the best rooting medium for tillering onion was 1/2 MS+NAA 0.1 mg/L,and the rooting rate was 100%;the best substrate ratio for transplanting and domestication of tillering onion was V(peat)∶V(soil)∶V(vermiculite)=2∶1∶1,and the survival rate was 98.67%.4.Under the experimental conditions,the plant height and prosthetic stem thickness of virus-free bulb of tillering onion were significantly higher than those of production seeds;the chlorophyll content,root activity,soluble sugar content,soluble protein content,POD and SOD activity of virus-free bulb were higher than those of production seeds;the total yield of virus-free bulbs was 2388.89 kg/667m~2,which was 16.08%higher than that of production seeds,and the bulb quality of tillering onion virus-free bulbs was slightly better than that of production seeds.In conclusion,the onion yellow dwarf virus was found to infect the main producing areas of tillering onion in Jilin Province(Halahai Town,Nongan county and Huaide Town,Gongzhuling City).On this basis,the virus-free technology system and micro bulb disk rapid propagation technology system of tillering onion were optimized and established,which had high virus-free efficiency and high proliferation coefficient.The yield of seed ball was significantly increased after virus-free,and could be used as reference It can provide some useful reference for the tillering onion seed industry in the future.