基质土壤与氮钾配合施用对菜用甘薯品质的影响

Effects of Interaction between Substrate and Fertilizer on Quality of Vegetable Sweet Potato

探究不同基质土壤中追施不同氮钾肥对菜用甘薯茎尖品质的影响,采用盆栽试验,以湖北主栽菜用甘薯“鄂菜薯10号”为供试材料,在泥炭土、有机基质栽培土、田间土中追施不同氮钾肥处理,测定菜用甘薯在不同处理下可溶性总糖、蔗糖、硝酸盐、总黄酮、总酚等品质指标.结果表明:增施氮肥降低了菜用甘薯茎尖总酚、总黄酮、绿原酸质量分数,提高了蔗糖和硝酸盐质量分数;钾肥降低了可溶性总糖质量分数;3种基质土壤类型对菜用甘薯硝酸盐呈显著正相关性.综合而言,3种基质土壤中田间土种植菜用甘薯总糖和多酚类物质积累最多,泥炭土中氮、钾肥追施量分别为3.22 g/m 2,0.69 g/m 2,有机基质栽培土每次追施钾肥0.69 g/m 2,田间土不施肥时可溶性总糖、蔗糖、总黄酮、总酚、绿原酸等积累效果最佳.

The effects of different nitrogen and potassium fertilizers on the quality of stem tip of vegetable sweet potato in different substrate soils were investigated by pot experiment.The main vegetable sweet potato cultivar“Ecaishu 10”in Hubei was used as the test material,and different nitrogen and potassium fertilizers were applied in peat soil,organic substrate soil and field soil.The quality indexes of soluble total sugar,sucrose,nitrate,total flavonoids and total phenols of vegetable sweet potato under different treatments were determined.The results showed that the application of nitrogen fertilizer reduced the mass fraction of total phenols,total flavonoids and chlorogenic acid in the stem tip of vegetable sweet potato,and increased the mass fraction of sucrose and nitrate.Potassium fertilizer reduced the total soluble sugar content.There was a significant positive correlation between the three types of substrate soils and the nitrate content of vegetable sweet potato.In general,the total sugar and polyphenols of vegetable sweet potato were the most accumulated in the field soil among three kinds of substrate soils.The amount of nitrogen and potassium fertilizer topdressing in peat soil was 3.22 g/m 2 and 0.69 g/m 2,respectively.The best effect of accumulation total sugar,sucrose,total flavonoids,total phenols and chlorogenic acid was achieved when 0.69 g/m 2 potassium fertilizer applied to the organic substrate soil each time,and the field soil without fertilization.