磷水平和接根瘤菌对紫花苜蓿根系形态特征和根瘤固氮特性的影响  

Effects of Phosphate Levels and Rhizobium Inoculation on the Root Morphology and Nitrogen-fixing Characteristic of Alfalfa

作　　者：郝凤[1] 刘晓静[1] 齐敏兴[1] 张晓玲[1] 

机构地区：[1]甘肃农业大学草业学院草业生态系统教育部重点实验室中美草地畜牧业可持续发展研究中心,甘肃兰州730070

出　　处：《草地学报》2015年第4期818-822,共5页Acta Agrestia Sinica

基　　金：国家自然科学基金项目(31460622);公益性行业(农业)科研专项(201403048-8)资助

摘　　要：以‘甘农3号'紫花苜蓿(Medicago sativa‘Gannong No.3')为材料,采用营养液沙培法,研究了磷及根瘤菌对紫花苜蓿根系形态和根瘤固氮酶活性的影响,结果表明:接种根瘤菌或在一定范围内(0~2000μmol·L^(-1))提高磷水平,均可显著增加紫花苜蓿的根长、根表面积、根平均直径、根体积和根系活力,并使其根瘤数增多,根瘤重增大,固氮酶活性显著增强,植株全氮含量增加;与不接菌相比,接菌提高了紫花苜蓿对磷的需求;本试验条件下紫花苜蓿所需磷素最佳范围为1000~1500/μmol·L^(-1)。The effects of phosphate levels and rhizobium on the root morphology and nitrogen-fixing characteristic of Medicago sativa ＇ Gannong No.3＇ were studied by sand culture method.The results showed that rhizobium inoculation and appropriately improving the phosphorus levels（0～2000μmol·L～（-1）） could markedly increase alfalfa root length,root surface area,average root diameter,root volume,root nodule number and root nodule weight,as well as root activities,nitrogenase activity and total nitrogen content;Rhizobium inoculation increased the demands of alfalfa for phosphate;The optimal phosphorus level of alfalfa is from 1000μmol·L～（-1） to 1500μmol·L～（-1）.

关 键 词：磷水平 根瘤菌 紫花苜蓿 根系形态 固氮酶活性 

分 类 号：S541[农业科学—作物学]