Studies On High Efficiency Virus-Free Technology Of Special Potato

Some regions of Xinjiang are not suitable for cultivation of cotton,but these regions'climate is very suitable for potatoes.As an asexually reproductive plant, potato is easily infected by viruses. The viruses can pass from one generation to the next, which might cause virus accumulation in potato and reduces the yield and quality of potato. The potato industry in Xinjiang is seriously influenced by virus diseases.The main kinds of viruses which reduce the yield of potato in Xinjiang are PVX and PVY. But there is still no efficiency prevention methods for virus diseases so far. The rapid and effective way of virus elimination is an important approach to gain virus-free plants which can improve yield and quality.The potato with viruses is obtained from Xishan farm (Zihuabai varieties). In order to eliminate the target viruses that is PVX and PXY, four eliminating methods were researched which are meristem-tip culture,heat treatment combined with meristem-tip culture,chemical treatment and heat treatment combined with chemical treatment.The result showed that the sprouting percentage and the virus-free rate were better when 0.3mm shoot tip ( With 1 of primordial leaves) was cultured by the meristem-tip culture. The quantum of basic seedlings and the effect of virus-free rate were best when the temperature was at 40℃for 4 hours, and 16℃for 20 hours in one day for 8 weeks; By chemical treatment with the meristem-tip culture,when the concentration of K2MnO4 was 3‰, the sprouting percentage was 75%,and the virus-free rate was 50% for PVX and 75% for PVY,respectively. In the chemical treatment,when the concentration was 5.0% of Urea, the sprouting percentage was 85%,and the virus-free rate were 60% for PVX and 80% for PVY ,respectively. When the potato was treated by chemical medicament and then by the shoot tip which was 0.4mm with 1 pair of primordial leaves was peeled off and cultured, the sprouting percentage and virus-free rate were higher than only using the meristem-tip culture. when the heat treatment combined with meristem-tip culture for test, the optimum treatment was 38℃for 4 hours, then 16℃for 20 hours with 9%of Urea, the PVX virus elimination rate was 60% and PVY virus elimination rate was 80%. All of the four methods can eliminate virus in this experiment; but relatively, When the potato was treated by chemical medicament and then by the shoot tip which was 0.4mm with 1 pair of primordial leaves was peeled off and cultured, can obtained the most virus-free potato seedlings, the highest virus-free rate and the highest work efficient, the method could be generalized in producing.