磷钾对紫云英(Astragalus sinicas L.)生长和土壤性状的影响

Effects of phosphorus and potassium on the growth and soil properties of Chinese milk vetch(Astragalus sinicus L.)

为研究不同区域磷钾养分对紫云英(Astragalus sinicas L.)生长和土壤性状的影响,为紫云英的高产栽培措施提供参考,在安徽合肥和广西南宁分别设置了不同磷钾养分添加的盆栽试验,测定了紫云英产量及养分累积量,并分析了土壤理化性状、胞外酶[α-葡萄糖苷酶(AG)、β-葡萄糖苷酶(BG)、磷酸酶(PHO)、乙酰氨基葡萄糖苷酶(NAG)、亮氨酸氨基肽酶(LAP)、β-木糖苷酶(XYL)]活性对磷钾养分的响应。结果表明:与不施肥处理相比,磷钾配施显著提升了安徽合肥紫云英鲜草产量和磷积累量,提升幅度分别为37.69%和54.01%;磷钾配施及单施钾肥处理对广西南宁紫云英全钾积累量分别提高了60.66%和59.23%。磷钾养分施用对安徽合肥土壤养分含量无显著影响,在广西南宁,单施磷肥显著提升了土壤有效磷和铵态氮含量,提升幅度分别为18.86%和75.59%;单施钾肥显著提升了土壤速效钾含量;磷钾配施显著提升了土壤速效钾和全氮含量。磷钾养分对安徽合肥6种土壤胞外酶活性皆有提升效果。土壤理化性状与酶活性在不同地区对紫云英鲜草产量贡献率不同,土壤理化性状中,安徽合肥土壤铵态氮、广西南宁土壤全氮对紫云英鲜草产量贡献率最高,分别为35.57%和21.82%;在6种胞外酶活性中,安徽合肥AG活性和广西南宁LAP活性贡献率最高,分别为25.56%和38.80%。由此可见,磷钾养分显著影响紫云英生长和土壤性状,影响程度与表现受土壤基础养分和地理环境的影响。在紫云英生长期添加适宜磷钾养分,可促进紫云英增产和土壤性状的改善,且磷钾配施效果最佳。

In order to study the effects of phosphorus(P) and potassium(K) on the growth and soil properties of Chinese milk vetch(Astragalus sinicus L.,CMV) in different regions and to provide reference for its high-yield cultivation measures,pot experiments were conducted in Anhui and Guangxi,the yield and nutrient accumulation of CMV were determined, soil physical and chemical properties,extracellular enzyme activities[α-glucosidase(AG),β-glucosidase(BG),phosphatase(PHO),acetylamino-glucosidase(NAG)leucine aminopeptidase(LAP),xylosidase(XYL)] were analyzed.The results showed that compared with no fertilization treatment,the combined application of P and K increased fresh yield and total phosphorus of CMV in Anhui by 37.69% and 54.01%,respectively.Total potassium accumulation of CMV were increased by 60.66% and 59.23% under the combined application of P and K and potash fertilizer only in Guangxi. P and K application had no significant effect on soil nutrient content in Anhui.In Guangxi,P fertilizer only increased the available P and ammonium nitrogen content by 18.86% and 75.59%;K fertilizer only increased soil available K content and the combined application of P and K increased the contents of available K and total N.And the activities of six soil extracellular enzyme activities in Anhui were increased.The contribution rates of soil physical and chemical properties and enzyme activities to fresh yield of CMV varied in different areas.Soil ammonium in Anhui and total N in Guangxi contributed most to fresh yields,and the contribution rates were 35.57% and 21.82%,respectively.For the influence of soil enzyme on CMV yield,AG in Anhui and LAP in Guangxi were the most important ones,with the contribution rates of 25.56% and 38.80%,respectively.The results showed that P and K significantly affected the growth and soil properties of CMV and soil properties,and the degree and performance of which were affected by soil basic nutrients and geographical environment.Application of suitable P and K fertilizer during the growth period of CMV could promote the increase of yield and the improvement of soil properties,and the combined application of P and K had the best effect.