氮肥施用量和种植密度对秦皇岛地区菜用甘薯茎尖产量和品质的影响

Effect of Nitrogen Fertilizer Application Rate and Planting Density on the Stem Tip Yield and Quality of Vegetable Sweet Potato in Qinhuangdao Area

为了明确秦皇岛地区菜用甘薯最佳氮肥施用量和种植密度配置方案,以台农71为材料,采用双因素试验设计,氮肥施用量设5个水平(0,120,180,240,300 kg/hm^(2)),种植密度设3个水平(12.50万,16.67万,25.00万株/hm^(2)),研究不同处理对菜用甘薯农艺性状、茎尖产量及主要品质指标的影响。结果表明,氮肥施用量显著影响菜用甘薯的品质和产量。可溶性蛋白质量分数随氮肥施用量增加一直增加,其最高值出现在最高氮肥用量处理,可溶性糖质量分数的最高值出现在240 kg/hm^(2)处理,其他指标最高值出现在180 kg/hm^(2)处理;产量最高值出现在240 kg/hm^(2)处理。种植密度对菜用甘薯茎尖农艺性状、茎尖产量和品质均具有显著影响:茎尖粗和叶宽随种植密度增加而下降;产量、节间长、叶柄长和叶长均随种植密度的增加而增加;可溶性蛋白、可溶性糖和花青素的质量分数随种植密度增加而减少,黄酮和总酚的质量分数随种植密度增加而增加。综合考虑茎尖产量、农艺性状与品质指标,秦皇岛地区菜用甘薯合理氮肥施用量为240 kg/hm^(2),种植密度为25万株/hm^(2)。

The effects of different treatments on agronomic traits,stem tip yield and main quality indexes of vegetable sweet potato in Qinhuangdao area was studied to clarify the optimal nitrogen fertilizer application rate and planting density configuration with a dual factor experimental design and taking Tainong 71 as the material under 5 levels of nitrogen fertilizer application(0,120,180,240,300 kg/hm^(2))and 3 levels of planting density(125000,166700,250000 plants/hm^(2)).The results showed that the nitrogen fertilizer application rate significantly affected the quality and yield of vegetable sweet potato.The soluble protein fraction increased with the increase of nitrogen fertilizer application,and its highest value appeared in the treatment with the highest nitrogen fertilizer application,the highest value of soluble sugar mass fraction appeared in the treatment of 240 kg/hm^(2),and the highest value of other indexes appeared in the treatment of 180 kg/hm^(2);the highest value of yield appeared in the treatment of 240 kg/hm^(2).Planting density had a significant effect on the agronomic traits,stem tip yield and quality of vegetable sweet potato:stem tip thickness and leaf width decreased with the increase of planting density;yield,internode length,petiole length and leaf length all increased with the increase of planting density;the mass fractions of soluble proteins,soluble sugars and anthocyanins decreased with the increase of planting density,and the mass fractions of flavonoids and total phenols increased with the increas of planting density.The optimal N fertilizer application rate for the stem tip yield,agronomic traits and quality indexes of vegetable sweet potato in Qinhuangdao area was 240 kg/hm^(2),and the planting density was 250000 plants/hm^(2).