牛角花齿蓟马为害对苜蓿无性系根茎叶及同化产物分配的影响  

Effects of Odontothrips loti( Thysanoptera: Thripidae ) damage on clone root,stem,leaf and assimilation product distribution of alfalfa

作　　者：胡桂馨[1,2,3] 彭然[1,2,3] 景康康[1,2,3] 方强恩[1,2,3] 张晓燕[1,2,3] 

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,兰州730070 [3]中-美草地畜牧业可持续发展研究中心,兰州730070

出　　处：《应用生态学报》2017年第9期2967-2974,共8页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金项目(31260579)资助~~

摘　　要：为探索同化产物分配利用与苜蓿耐蓟马的关系,本试验以扦插的抗蓟马苜蓿无性系R-1和感蓟马苜蓿无性系I-1为材料,研究不同虫口牛角花齿蓟马为害对苜蓿的抗性、根、茎和叶生长特性及可溶性糖含量的影响.结果表明:随着虫口压力的增大,R-1和I-1苜蓿的受害指数升高;在相同虫口压力下,R-1苜蓿的受害指数显著低于I-1.受蓟马为害后,R-1和I-1苜蓿株高降低、叶面积减少、茎秆变细、节间长变短、节间数增加,根颈和主根直径加粗、侧根增多.在低虫口密度下,随虫口压力增大,R-1和I-1苜蓿地上部生物量增加,根冠比下降,分配到茎的生物量比例升高;在高虫口密度下,地上部生物量随虫口压力增大而减少,根冠比增加,分配到根系的生物量比例升高;R-1根冠比和茎生物量比例随虫口压力变化曲线的拐点均为每枝条5头,I-1根冠比和茎生物量比例随虫口压力变化曲线的拐点均为每枝条3头.在低虫口压力下,R-1苜蓿茎和叶中的可溶性糖含量随虫口压力增加而升高;在高虫口压力下,茎和叶中的可溶性糖含量随虫口压力增加而下降;根中可溶性糖含量随虫口压力增加持续下降.I-1根、茎和叶中的可溶性糖含量均随虫口压力增加持续下降.牛角花齿蓟马为害后,R-1根、茎和叶的农艺性状及抗性比I-1好,对同化产物的分配利用率高.In order to find the correlation between assimilation product distribution in alfalfa organs and its tolerance to Odontothrips loti, the resistance, growth characters and soluble sugar in roots, stems and leaves were evaluated under different O. loti densities, using resistant clone （R-1） and susceptible clone （I-1） as indicating materials. The results showed that the damage index of R-1 and I-1 increased with increasing thrips density, and the damage index of R-1 was significantly （P 〈0.05） lower than that of I-1 under the same thrips density. For both R-1 and I-1, the plant height, leaf area, stem diameter and intemode length decreased after O. loti damaged, meanwhile the intemode number, the diameter of collar root and main root and lateral root number increased. Under the low pest density, the aboveground biomass of R-1 and I-1 clones increased with the increasing pest density, but the root to shoot ratio decreased. Under the high pest density, the aboveground biomass decreased with the increasing pest density, but the root to shoot ratio increased. The curve inflection points between the root to shoot ratio and pest density, and between the stem biomass and pest density were 5 thfips adult per branch for R-1 clone, and 3 thrips adult per branch for I-1 clone. For R-1, under the low pest density, the soluble sugar content in stems and leaves increased with the increasing pest density. Under high pest density, the soluble sugar content in stems and leaves decreased with the increasing pest density. The soluble sugar content in roots of R-1, and in stems, leaves and roots of I-1 decreased with the increasing pest density. In conclusion, the agronomic traits, resistance and utilization of assimilation distribution of R-1 alfalfa were higher than those of I-1 alfalfa.

关 键 词：牛角花齿蓟马 苜蓿 耐害性 同化产物 

分 类 号：S435.4[农业科学—农业昆虫与害虫防治]