玉米自交系对朱砂叶螨的抗性评价

采用田间罩网接螨和室内盆栽接螨,以叶片危害指数、螨情指数、田间种群密度和种群增长倍数为指标,评价8份自交系玉米对朱砂叶螨(Tetranychuscinnabarinus)的抗性。田间鉴定表明,在苗期和花粒期用叶片危害指数、螨情指数和田间种群密度3种抗性评价指标评价时,自交系HL6044均表现为高抗;用叶片危害指数和螨情指数评价时,自交系ES40在苗期和花粒期均表现为高感;用田间种群密度评价时,ES40在苗期表现为高感,花粒期则表现为中感。室内接螨后20 d,朱砂叶螨种群增长倍数在HL8039和ES40上分别为23.36和24.13倍,在HL6044上仅为2.44倍。8份自交系玉米中,HL6044对朱砂叶螨表现为高抗,叶片危害指数适用于田间玉米抗螨性评价。

Evaluation on the Resistance of Maize Inbred Lines to Tetranychuscinnabarinus

With maize covered with network in field and potted in the laboratory, and then inoculated with mites, the resistance of 8 maize inbred lines to Tetranychuscinnabarinus were evaluated on leaf hazard index, mite sentiment index, mite population density as well as population growth multiple. The results in field showed that maize inbred line HL6044 was characterized highly resistance at both the seedling stage as well as the stage of flowering and seeding on leaf hazard index, mite sentiment index as well as mite population density, while ES40 highly susceptible on leaf hazard index and mite sentiment index at both the seedling stage as well as the stage of flowering and seeding, however, it was characterized highly susceptible on population density at seedling stage, moderately susceptible at the stage of flowering and seeding. On the 20th day after inoculation with mites in the laboratory, population growth multiples of the mites on HL8039 and ES40 were the biggest, and they were 23.36 and 24.13 times, respectively, while that on HL6044 was the smallest, only 2.44 times. These indicated that HL6044 of 8 maize inbred lines performed high resistance to T.cinnabarinus and leaf hazard index was suitable for evaluating the resistance of maize to mites in field.