榆紫葉甲病原菌分離及生防菌的篩選與鑒定

胡基華 陳靜宇 曹旭 姜威 劉宇帥 孟利強(qiáng) 李晶 張淑梅

摘要[目的]探尋防治榆紫葉甲病的生防菌株。[方法]從榆紫葉甲蟲體上分離菌株后進(jìn)行培養(yǎng)，并對室內(nèi)飼養(yǎng)的榆紫葉甲各齡幼蟲進(jìn)行致病性試驗(yàn)。[結(jié)果]從感病榆紫葉甲成蟲蟲體上分離到18個(gè)菌株，其中12個(gè)菌株具有幾丁質(zhì)和蛋白質(zhì)降解活性。5個(gè)菌株對1～2 齡幼蟲表現(xiàn)出不同程度的致病力，在接種后1～3 d幼蟲開始死亡，處理后7 d 幼蟲的累積死亡率為21.2%～46.8%，其中YJA-03和YJA-10菌株的累積死亡率>30.0%。YJA-03菌株為革蘭氏陽性菌，經(jīng)過形態(tài)學(xué)、生理生化特性和PCR 擴(kuò)增鑒定確定它屬于短桿菌屬（Exiguobacterium）。YJA-10菌株為革蘭氏陰性菌，經(jīng)鑒定其屬于Glutamicibacter屬。[結(jié)論]YJA-03和YJA-10菌株可用作防治榆紫葉甲病的生防菌。

關(guān)鍵詞榆紫葉甲；生物防治；菌株分離；生理生化特性

中圖分類號S763.38文獻(xiàn)標(biāo)識碼A文章編號0517-6611（2017）11-0003-04

Abstract[Objective] To explore the pathogen for the biological control of Ambrostoma quadriimpressum. [Method] Some bacteria strains were isolated from A. quadriimpressum to determine the pathogenicity of Bacillus thuringinensis to each instrar of larvae fed in the laboratory. [Result] 18 bacterial isolates were obtained from diseased adults of A. quadriimpressum， among them 12 isolates showed proteindegrading and chitindegrading activities. 5 isolates showed different pathogenicity to 1stinstar and 2ndinstar larvae of A. quadriimpressum. The larvae began to die during 3-7 d after inoculation， and the accumulative mortality rate of larvae of A. quadriimpressum was 21.2%-46.8%. The accumulative mortality rate of A.quadriimpressum larvae to YJA03 strain and YJA10 strain were more than 30%. YJA03 was identified as Grampositive bacterium， a bacteria of genus Exiguobacterium identified by morphological， physiological and biochemical characteristics and PCR amplification. YJA10 was identified as Gramnegative bacterium， belonging to genus Glutamicibacter. [Conclusion] YJA03 strain and YJA10 strain can be used for the biological control of A. quadriimpressum.

Key wordsAmbrostoma quadriimopressum Motschulsky；Biological control；Strain isolation；Physiological and biochemical characteristics

榆紫葉甲（Ambrostoma quadriimopressum Motschulsky）隸屬鞘翅目葉甲科，其食性專一，僅取食榆樹芽苞、葉片，常將葉片吃光，使樹勢衰弱并引起其他病蟲危害，在黑龍江、吉林、遼寧和內(nèi)蒙古等地危害嚴(yán)重[1-2]。近年來，榆樹已經(jīng)逐漸成為城市園林綠化的重要樹種，榆紫葉甲的危害程度日益加大，嚴(yán)重影響城市園林綠化景觀，同時(shí)造成了極大的經(jīng)濟(jì)損失。目前，主要依靠廣譜性的化學(xué)農(nóng)藥進(jìn)行防治，雖然在短時(shí)間內(nèi)可快速控制種群數(shù)量，但是害蟲一旦產(chǎn)生抗藥性，就會有再度猖獗的現(xiàn)象。同時(shí)，也給環(huán)境帶來了污染，隨著人們對環(huán)境問題的關(guān)注越來越多以及對環(huán)境保護(hù)意識的增強(qiáng)，人們不斷探索以生物農(nóng)藥為主的無公害防治方法。蘇……