【摘要】 利用田间试验研究了不同钾肥品种和施钾时期对旱地和水浇地马铃薯块茎产量、品质和钾肥利用效率的影响。在钾肥用量相同的条件下选择氯化钾（KCl）、硫酸钾（K₂SO₄）和硝酸钾（KNO₃）3种钾肥品种，分别在种前基施、分次施用（50%播前基施+50%花期追施）和全部花期追施，并设不施钾肥对照处理。结果表明，与不施钾肥对照相比，在内蒙古施用钾肥显著提高了旱地和水浇地的马铃薯块茎产量，且KNO₃播前基施或分次施用块茎产量最高，但在甘肃试验上只有播前基施KCl显著提高了块茎产量。与不施用钾肥的对照相比，施用钾肥还增加了马铃薯对钾的吸收，改善了块茎品质。多因素方差分析结果表明，在旱地和水浇地上，不同钾肥品种对马铃薯产量、钾素吸收量、商品薯率、单薯重和淀粉含量影响无显著差异，但显著影响还原糖含量，旱地条件下施用KCl和水浇地下施用KNO₃的还原糖含量比施用K₂SO₄低。钾肥施肥时期显著影响旱地和水浇地马铃薯块茎产量和钾素吸收量，钾肥播前基施比全部花期追施块茎产量高，钾素吸收量大，与分次施用相当。施用KCl的农学效率（AE_K）高于或相当于施用K₂SO₄，播前基施钾肥的AE_K比分次施肥和全部花期追施高。综上所述，马铃薯产量和品质对施用KCl的响应优于或相当于K₂SO₄和KNO₃，在试验区马铃薯生产中推荐播前基施KCl。更多还原

【Abstract】 Field trials were conducted to study the influences of potassium（K）sources and application time on tuber yield,quality and K efficiency of rainfed and irrigated potato（Solanum tuberosum L.）.Three K sources,i.e.potassium chloride （KCl）,potassium sulfate（K₂SO₄）,potassium nitrate（KNO₃）,were selected and applied,respectively,at three times,i.e.totally base application,split（50%base application and 50%topdressing at flowering）and totally topdressing at flowering in the same rate of K.The control without K fertilizer was included.Results indicated K fertilization significantly increased tuber yield of rainfed and irrigated potato in Inner Mongolia site,compared with control without K,and base application or split application of KNO₃ got the highest yield,but only base application of KCl significantly increased tuber yield in Gansu site.K fertilizers also increased K uptake,improved tuber quality,compared with control without K application.Multivariate analysis of variance showed that in rainfed and irrigated conditions there was no significantly different effect on tuber yield,K uptake,commercial rate,average tuber weight and starch content between K sources,but KCl in rainfed or KNO₃ in irrigated condition resulted in lower reducing sugar content than K₂SO₄.Application times of K significantly affected tuber yield and K uptake of rainfed and irrigated potato.Base application of K produced more tuber yield,K uptake than totally topdressing and similar results to split application.KCl resulted in similar or higher agronomic efficiency of K（AE_K）than K₂SO₄,and KNO₃ resulted in a greater AE_K than KCl and/or K₂SO₄ mainly in Inner Mongolia site.Base application of K resulted in higher AE_K than split and/or totally topdressing.In summary,the response of potato yield and quality to KCl application was better than or equivalent to K₂SO₄ and KNO₃.Base application of KCl could be recommended in potato production in experimental area.更多还原