蜡样芽孢杆菌B3-7在大田小麦根部的定殖动态及其对小麦纹枯病的防治效果  

Colonization dynamics of Bacillus cereus B3-7 on wheat roots and control efficiency against sharp eyespot of wheat

作　　者：黄秋斌 张颖[1] 刘凤英[1] 王淼[1] 王刚[1,2,3] 

机构地区：[1]河南大学生命科学学院,开封475004 [2]棉花生物学国家重点实验室,开封475004 [3]河南大学生物工程研究所,开封475004

出　　处：《生态学报》2014年第10期2559-2566,共8页Acta Ecologica Sinica

基　　金：国家自然科学基金(30771435;30971952;31200069);棉花生物学国家重点实验室开放课题(CB2013A27)

摘　　要：为了阐明蜡样芽孢杆菌B3-7在大田条件下的生态适应性以及对于小麦纹枯病的生防效果,通过利用绿色荧光蛋白编码基因gfp标记生防菌株B3-7,室内比较了GFP标记菌株和原始出发菌株在菌落形态、生长特性,生物薄膜产生以及在小麦根部定殖等方面的特性,结果发现GFP标记菌株和出发菌株在上述特性方面无明显差别。在此基础上,大田条件下测定了GFP标记菌株在小麦根部的定殖动态和对于小麦纹枯病的生防效果。结果发现,GFP标记菌株在小麦根部能够长期定殖,其存在量在小麦分蘖期最大,每克根重达到105CFU,拔节期后,该细菌数量一直维持在104CFU之上。同时发现,生防菌株能够有效降低小麦纹枯病的严重度和提高罹病小麦的产量。小麦分蘖期、孕穗期和灌浆期生防菌对于小麦纹枯病的防治效果分别达到60%、34%,34%,小麦成熟后产量提高13%—15%。结果表明,B3-7在大田条件下具有较好的生态适应性和防治小麦纹枯病的能力。Sharp eyespot of wheat is caused by the fungus Rhizoctonia cerealis and is an important soil-Borne disease of wheat worldwide. At present, no commercially cultivated disease resistant varieties are available to efficiently protect wheat against infection by this pathogen. Control of the plant disease sharp eyespot currently relies on application of pesticides such as Triadimefon and Validamycin; however, pesticides are expensive and pose serious health and environmental hazards. Persistent application of pesticides can cause selection of pesticide resistant pathogenic fungi. Biological control is an environmentally sound and effective means of reducing or mitigating plant diseases and the effects of plant pathogens through the use of natural microorganisms. In the rhizosphere （ on the plant root or in close vicinity to the root） bacteria are abundant, most often organized in microcolonies. Bacteria in the rhizosphere, known as rhizobacteria, not only benefit from the nutrients secreted by the plant root but also beneficially influence the plant in a direct or indirect way, resulting in stimulation of plant growth. Among the beneficial microorganisms isolated from the rhizosphere, Bacillusspp. offer severaladvantages over fluorescent pseudomonads and other Gram-negative bacteria as seed inoculants for protection against root pathogens. Bacillus spp. have a long shelf life because of their ability to form endospores and their unique mechanisms of action as they can produce broad-spectrum antibiotics and compete for ecological niches against plant pathogenic fungi. Bacillus cereus B3-7, a biological control strain isolated from the wheat rhizosphere, shows potential for control of sharp eyespot and for efficient yield increase in wheat. To elucidate the ecological adaptability of B3-7 and its efficacy for biological control of sharp eyespot of wheat under field conditions, the green fluorescent protein （gfp） gene was inserted into the B3-7 genome and a GFP-tagged B3-7 strain was constructed. Colony shape, g

关 键 词：定殖 生物防治 小麦纹枯病 蜡样芽孢杆菌 

分 类 号：S476[农业科学—农业昆虫与害虫防治]