关键词: 苜蓿品种, 牛角花齿蓟马, 产量损失率, 株高, 分枝

Abstract: Odontothrips loti Haliday is one of the most important pests which affect hay yield and quality of alfalfa seriously in north China.At present,controlling methods on this pest is pesticide spraying.However,it has hardly any ideal effect using single controlling method because of the short growth period,miniature body,easy enshrouded,and anti-pesticide of the thrips.Using varieties resistant to insect is one of the most effective approaches to solve thrips damage on alfalfa ultimately.In this study,the tolerances of 8 alfalfa varieties to O.loti were evaluated at alfalfa 6-leaf-stage by infecting 3,5 and 10 adult thrips per plant,respectively.The results indicate,after 5 day feeding by thrips,the damage indices of all alfalfa varieties were increased significantly and the plants from some varieties were dead along with the increased thrips density.M8 and HA-3 alfalfa were the resistant varieties to O.loti in this study,Ja alfalfa was susceptible,and other varieties were medium.Accordingly,the yield loss ratios of HA-3 and M8 were the lowest, Ja alfalfa the highest,and other varieties medium;same situations as the plant height and branching.In summary,the tolerance of Ja alfalfa to O.loti was the poorest,while HA-3 and M8 were the best.

Key words: Alfalfa variety, Odontothrips loti Haliday, Yield loss ratio, Height, Branch