不同时期追施氯化钾对莴笋产量和品质的影响

为了研究不同时期追施氯化钾对莴笋产量和品质的影响，为生产高产优质叶菜提供科学依据，采用田间小区试验研究不同时期追施氯化钾对莴笋产量和品质的影响。结果表明，不同时期追施钾肥均较基施钾肥(CK2)处理降低莴笋产量，随着莴笋生长时期的变化追施钾肥，莴笋产量逐渐降低，且随追施钾肥时期后移莴笋产量降幅逐渐增大。不同时期追施钾肥对莴笋叶维生素C和氨基酸含量影响表现不一。莴笋可溶性糖含量以基施钾肥(CK2)处理最高。而不同时期追施氯化钾可降低莴笋硝酸盐含量，系氯抑制土壤NO3--N的形成和根系吸收。不同时期追施钾肥对莴笋叶全氮含量影响不大，莴笋茎全氮含量以基施钾肥(CK2)处理最高；莴笋叶和茎全磷和全钾含量均以基施钾肥(CK2)处理最高，基施氯化钾有利于提高莴笋全氮、磷、钾含量。莴笋全氯含量随莴笋生长时期追施钾肥后移而升高。

Effect of Topdressing Potassium Chloride Fertilizer on Yield and Quality of Lettuce in Different Growth Periods

In order to study the effect of topdressing potassium chloride on the yield and quality of lettuce in different growth periods and provide scientific basis for the production of high yield and good quality of leaf vegetables, field experiments were set up to study effects of topdressing potassium chloride fertilizer on yield, quality and nutrient of lettuce in different growth periods. Results indicated that compared to basal application （CK2） treatment, yield of lettuce were reduced topdressing potassium fertilizers in different growth periods. Yield of lettuce were gradually reduced along with the change fertilizer, and yield reduction of lettuce were gradually increased shift after. Effect on vitamin C and amino acid content of lettuce in lettuce growing periods applying potassium with the period of applying potassium fertilizer leaf with different periods applying potassium fertilizer were different. The treatment of largest soluble sugar content of lettuce was basal application （CK2）. But nitrate content of lettuce were reduced with topdressing chloride could inhibit the formation of NO3--N and uptake potassium chloride fertilizer in different periods, of root. Applying potassium fertilizers in different periods on total nitrogen content of lettuce leaf had little change, the treatment of highest total nitrogen content of lettuce stem was basal application （CK2）. And the treatment of highest total phosphorus and potassium content of lettuce was basal application （CK2）. So potassium chloride as basal application improved nitrogen,phosphorus, potassium content. Total chloride content of lettuce was improved along with the period of applying potassium fertilizer shift after.