Study On The High Efficiency And Low-expesive Rapid Propagation Technology In Virus-free Sweet Potato Seedling

The virus-free sweet potato ‘Ganshu 1’ plantlets were studied by the single factor and orthogonal test methods. The culture conditions(medium type, sustentation, water source,light source, carbohydrate source, sugar concentration, hormone concentration and organic compound concentration) were analyzed. The morphological indices(leaves, roots, stem tip and plant height) were measured and evaluated.The single factor results revealed that the plantlets cultured on the 1/2MS medium,shallow-layer liquid medium, tap water-fluorescent light and 6% soft sugar accordingly had the optimal indices with new leaves 4.83, 4.67, 5.00 and 5.33; roots 2.17,1.67 1.67 and 1.50;stem tip 6.67, 5.33,5.67 and 5.17; and plant height 2.17, 3.08, 2.73 and 2.50 cm respectively.The order and contribution rate of every culture condition on the target index was as following: light、sustentation、medium type、water、soft sugar concentration、carbohydrate source. the orders of all hormonal factors and organic matter affecting the sum of the indexes of the sweet virus-free plantlet were as follows:6-BA、NAA 、IAA; niacin、inositol 、VB1 、glycine、VB6. The optimal culture condition was 1/2MS + shallow-layer liquid medium + tap water + LED lights + 30 g/L soft sugar in virus-free sweet potato seedling rapid propagation.The virus-free sweet potato seedlings showed the best growth performances using the optimal culture condition. Additionally, it can shorten the culture period furthermore and reduce more than 81.04% cultivating cost. The best combining concentrations of hormone and organic matter were as follows: NAA(0 mg.L-1) +6-BA(0.1 mg.L-1) +IAA(0.1 mg.L-1); glycine(3.0mg.L-1) +VB1(0.6 mg.L-1) +VB6(0.25 mg.L-1) + niacin(100 mg.L-1) + inositol(1.00 mg.L-1).The propagation sweet potato were up to if cultivated under the constant temperature and the above combining concentrations for 30 days.