苜蓿不同品种AMV和WCMV带毒检测及生理生化特性研究

为明确甘肃省大面积种植的苜蓿品种苜蓿花叶病毒（AMV）和白三叶草花叶病毒（WCMV）带毒情况及这两种病毒侵染后对苜蓿生理生化特性的影响。利用双抗夹心酶联免疫吸附分析法（DAS-ELISA）和生理生化方法分别对种植于实验室30 d苗龄的12个苜蓿品种进行了带病毒检测及携带不同病毒的苜蓿叶绿素、可溶性蛋白含量、防御酶活性的测定。结果表明12个苜蓿品种可分为不携带病毒、携带病毒AMV、携带病毒WCMV、携带病毒AMV和WCMV，病毒检出率为66.7%，其中AMV检出率为50.0%、WCMV检出率为41.7%、AMV和WCMV复合侵染率为25.0%。方差分析表明，两种病毒复合侵染、AMV、WCMV单独侵染与不带病毒（CK）相比，苜蓿叶绿素、可溶性蛋白含量均显著降低，而3种防御酶过氧化物酶 （POD）、多酚氧化酶 （PPO）、苯丙氨酸解氨酶 （PAL）的活性均显著升高，且两种病毒复合侵染的苜蓿叶绿素、可溶性蛋白含量均低于两种病毒单独侵染；而POD、PPO、PAL均高于两种病毒单独侵染。结果表明AMV、WCMV侵染不同品种苜蓿对其生理生化活性有较大的影响。

Detection of alfalfa mosaic virus and white clover mosaic virus in alfalfa and their effects on physiological and biochemical characteristics of alfalfa plants

In this study， we screened alfalfa （Medicago sativa） varieties that are grown on a large scale in Gansu Province for the presence of alfalfa mosaic virus （AMV） and white clover mosaic virus （WCMV）， and determined the physiological and biochemical effects of these viruses on alfalfa plants. Twelve alfalfa varieties were cultivated in the laboratory for 30 days， and then viruses were detected using double antibody sandwich enzyme-linked immunosorbent assays. The effects of the viruses were determined by measuring the chlorophyll content， the activities of defensive enzymes， and the contents of soluble protein in alfalfa seedlings. The 12 alfalfa varieties could be divided into four groups： a non-infected group， an AMV-infected group， a WCMV-infected group， and an AMV/WCMV-infected group. Among all the plants， 66.7% were infected by one or both viruses （50% positive for AMV； 41.7% positive for WCMV， and 25% positive for AMV/WCMV）. Analyses of variance indicated that AMV/WCMV co-infection and single-virus infection significantly decreased the chlorophyll content and the soluble protein content in alfalfa plants， compared with uninfected plants （CK）. AMV/WCMV co-infection significantly decreased the chlorophyll content and the soluble protein content in alfalfa plants， compared with those infected with a single virus. Compared with uninfected plants and those infected by a single virus， plants co-infected with both AMV and WCMV showed significantly increased activities of defensive enzymes including peroxidase， polyphenol oxidase， and phenylalanine ammonia-lyase. Our findings show that infection with AMV and/or WCMV significantly affects the physiological and biochemical characteristics of different alfalfa varieties.