牛角花齿蓟马为害对紫花苜蓿生长及氮代谢的影响  

Effects of Odontothrips loti damage on alfalfa growth and nitrogen metabolism

作　　者：寇江涛[1,2] 师尚礼[1,2] 胡桂馨[1,2] 

机构地区：[1]甘肃农业大学草业学院,兰州730070 [2]草业生态系统教育部重点实验室,甘肃省草业工程实验室,中-美草地畜牧业可持续研究中心,兰州730070

出　　处：《植物保护》2014年第4期14-20,共7页Plant Protection

基　　金：国家现代牧草产业技术体系建设专项(CARA-35);全国种质资源保种项目(NB2130135);教育部高校博士学科点基金(20106202110003);农业部行业专项(201003023);国家自然科学基金项目(31260579)

摘　　要：为了明确牛角花齿蓟马为害对紫花苜蓿生长及氮代谢的影响,测定了不同牛角花齿蓟马虫口密度下抗、感蓟马苜蓿无性系R-1、I-1的受害指数、单株生物量及氮代谢的变化。结果表明:(1)随着牛角花齿蓟马虫口密度的增加,R-1、I-1无性系各接虫处理的受害指数均升高、单株生物量均下降,在相同牛角花齿蓟马虫口密度下,R-1无性系的受害指数及产量损失率均低于I-1无性系。(2)受牛角花齿蓟马为害后,R-1无性系各接虫处理硝酸还原酶活性上升后趋于稳定,硝态氮含量呈先上升后下降的趋势,游离氨基酸含量呈持续上升的趋势;I-1无性系各接虫处理的硝酸还原酶活性呈先上升后下降的趋势,硝态氮含量呈先下降后上升的趋势,游离氨基酸含量上升后趋于稳定或下降。结果说明:硝酸还原酶活性的升高是R-1无性系对蓟马诱导抗性的一种表现,而I-1无性系氮代谢失调是其感蓟马的主要原因之一,因此R-1无性系的适应能力强,受害较轻,对牛角花齿蓟马为害的抗性和补偿生长能力高于I-1无性系。Damage index,individual biomass and nitrogen metabolism were investigated on alfalfa clones R-1 and I-1,resistant and susceptible to Odontothrips loti,respectively,under different pest densities to determine the effects of O.loti damage on alfalfa growth and nitrogen metabolism.The results indicated that：（1）all damage indices of both R-1 and I-1increased and individual biomasses decreased as pest density increased,and at the same density level,damage index and yield loss of R-1 were lower than those of I-1;（2）after being damaged by thrips,NR（nitrate reductase）activity of all inoculated R-1increased till stabilization,and nitrate nitrogen content firstly increased and then decreased,and free amino acids increased continuously;NR activity of all inoculated I-1 firstly increased and then decreased,while nitrate nitrogen content decreased firstly,followed by increase;free amino acid content firstly increased,then remained stable or decreased.These results indicated that the increase of NR activity was a manifestation of induced resistance of R-1 to thrips,while nitrogen disorder of I-1 is the main reason leading to their susceptibility,all of which ultimately resulted in stronger adaptability and minor damage of R-1,as well as stronger resistance and compensation growth capability than I-1.

关 键 词：紫花苜蓿 牛角花齿蓟马 受害指数 单株生物量 氮代谢 

分 类 号：S433.89[农业科学—农业昆虫与害虫防治]