黄土旱塬区扦插密度对不同蔓型甘薯品种生长和产量的影响

Effects of Transplanting Density on Plant Growth and Yield of Different Tendril Types in Sweet Potato in Rainfed Loess

为了确定不同蔓型甘薯品种最佳种植密度,选取短蔓型品种(晋甘薯9号)、长蔓型品种(济薯25),在大田试验条件下,研究不同扦插密度下各项群体生理指标与甘薯产量及构成因子的关系。结果表明,扦插密度对2个甘薯品种的群体生理指标、单株鲜薯质量、产量及商品薯率有显著的调控效应;随密度的增加,单株鲜薯质量降低,产量呈先上升后降低的抛物线状;叶面积指数(LAI)增加,叶绿素含量降低,不同生育期不同密度处理薯蔓比(T/R)值表现不一;晋甘薯9号以4.8万株/hm^2、济薯25以3.9万株/hm^2密度种植,在甘薯生产中可形成良好的群体结构,有利于单位面积株数、薯数和薯质量的协调发展,使甘薯产量达到最高。不同蔓型甘薯品种有不同的适宜扦插密度。

The experiments were conducted to evaluate the effects of transplanting density on plant growth and yield of different tendril types in sweet potato in rainfeding loess in field in 2014 and 2015.Shorter tendril sweet potato cultivar Jinganshu 9 and longer tendril cultivar Jishu 25 were used.The results showed that transplanting desity had significant regulation on population physical indicators,sweet potato quality per plant,yield and commodity sweet potato rate.Sweet potato yield per plant decreased with plant density increase,and yield had quadratic function relationship with density.LAI increased and chlorophyll content decreased with density increase.Tube/shoot(T/R)had diferrent values in different growth stages for two varieties.The optimum densities were 48 000 plants/hm2 for Jinganshu 9 and 39 000 plants/hm2 for Jishu 25,respectively.Therefore,different tendril types of sweet potato variety had different optimum density.