摘要
Abstract
To expand the propagation pathways of virus-free sweet potato original seeds and improve the efficiency of virus-free seedling multiplication,vine tips of the cultivar Shangshu 19 were cut and planted in a solar greenhouse for overwintering seedling cultivation.Rooting promotion experiments were conducted using different concentrations of naphthalene acetic acid(NAA),calcium fertilizer,titanium fertilizer,and potassium dihydrogen phosphate.The number of roots per plant,root weight per plant,and weight per single root were compared among treatments.A split-plot design was adopted,with planting density as the main treatment(M1:400 000 plants/hm2,M2:533 333 plants/hm2,M3:666 667 plants/hm2,M4:800 000 plants/hm2)and planting method as the sub-treatment(Y0:direct planting;Y1:dipping the lower 6 cm of seedlings in 30 mg/L NAA solution for 1 h before planting;Y2:direct planting followed by two foliar sprays each of 58.33 mg/L water-soluble calcium fertilizer,30 mg/L water-soluble titanium fertilizer,and 3 g/L potassium dihydrogen phosphate after seedling establishment;Y3:Y1+Y2).The number of dead seedlings after overwintering,the seedling yield(number of vine tips and vine segments)over three harvests,and the weight per 100 seedlings were compared and analyzed.The results showed that the optimal concentrations for promoting root growth of overwintering vine tips were 30 mg/L NAA,58.33 mg/L water-soluble calcium fertilizer,30 mg/L water-soluble titanium fertilizer,and 3 g/L potassium dihydrogen phosphate.Treatments Y1,Y2,and Y3 significantly reduced the mortality rate of overwintering seedlings,and Y3 significantly increased the total seedling yield over the three harvests.The total seedling yield over the three harvests increased significantly with increasing planting density,but the weight per 100 seedlings for vine tips and vine segments was negatively correlated with density.Comprehensive analysis indicates that treatment with 30 mg/L NAA,58.33 mg/L water-soluble calcium fertilizer,30 mg/L water-soluble titanium fertilizer,and 3 g/L potassium dihydrogen phosphate promotes root growth,reduces mortality,and increases seedling yield of overwintering Shangshu 19 seedlings.Increasing planting density can enhance seedling yield but reduces the weight per 100 seedlings.关键词
甘薯/育苗/脱毒/越冬/商薯19Key words
sweet potato/seedling raising/virus elimination/overwintering/Shangshu 19分类
农业科技
