[目的]分离鉴定萝卜蚜的病原真菌,并测定其对萝卜蚜的致病性.[方法]采用形态学方法进行病原真菌种类鉴定,利用孢子浴方法对萝卜蚜进行致病性测定.[结果]初生分生孢子,卵形,双囊壁,单核,(24.7±1.4)μm×(10.7±0.9)μm, L/D=2.3±0.2.次生分生孢子形似初生分生孢子,大小为:(18.6±2.1)μm×(13.3±1.3)μm,L/D=1.4±0.2.菌丝段菌丝状,直径为(10.6±0.8)μm.分生孢子梗掌状分枝,直径(10.0±0.9)μm 假囊状体不分枝,基部粗大,直径(19.2±1.7)μm,向端部渐尖,直径(8.0±0.9))μm.假根单菌丝状,基部直径(21.0±3.0)μm,底端具有规则的盘状固着器.休眠孢子未见.该菌对萝卜蚜的致死中量为18.21 cfu/mm2.[结论]感染萝卜蚜的昆虫病原真菌被鉴定为新蚜虫疠霉, 该菌对萝卜蚜表现出较强的致病性.%[ Objective ] The study was to isolate and identify the pathogen of Lipaphis erysimi and to determine its pathogenicity against L. erysimi. [ Method ］ Based on the morphological characteristics, the species of pathogenicfungus was identified. Spore shower method was used to deter mine the pathogeni-city against L. erysimi. [ Result ] Primary conidia, ovoid, bitunicate and uninucleate, ( 24.7 + 1.4 ) μm × ( 10.7±0.9 ) μm, L/D = 2.3 ± 0.2. Sencondary conidia had the similar shape with the primary ones, ( 18.6 ± 2.1 ) μm × ( 13.3 ± 1.3) μm, L/D = 1. 4 ±0.2. Hyphal fragment was like mycelium with the diameter of ( 10.6 ±0.8) μm. Conidiophores had palmate branch with the diameter of (10.0 ± 0.9) μm. False cystidia was not branched, which had rough base with the diameter of (19.2 ± 1.7 ) μm, and gradually became more angular towards the apex with the diameter of (8.0 ± 0.9) μm diameter at tips. Rhizoid was like monohyphal shape with the diameter of (21.0 ±3.0) μm at base, the terminal apex had regular discoid holdfast. No dormancy spores was observed. The lethal dose of the pathogen against L. erysimi was 18.21 cfu/mm2. [ Conclusion ]The entomopathogenic fungus against L. erysimi was identified to be Pandora neoaphidis, and the pathogen was confirmed to have strong pathogenicity against L. erysimi.
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