番茄灰霉病生物防治菌株的筛选

从土壤中筛选出对番茄灰霉病菌(Botrytis cineren Pers．)有较强拮抗作用的生物防治菌株94株，其中拮抗细菌22株，分离率为17.6％；拮抗放线菌53株，分离率为11．7％；拮抗木霉菌19株，分离率为28.8％。研究发现，拮抗细菌可产生抗生素类物质，且在121℃高温下处理30min不失活，放线菌的抗生物质大多不耐热。拮抗木霉菌具较强的营养竞争及重寄生作用．温室接种试验表明对番茄叶部灰霉病的防治效果达67．18％。     

四川松树内生拟盘多毛孢的多样性及其防病效果

【目的】对四川松树内生拟盘多毛孢Pestalotiopsis的生态分布及其对松树病害的防治效果进行分析,为松树病害无公害治理提供理论与实践基础。【方法】对分布于四川的松树内生拟盘多毛孢的多样性进行调查统计,分析树种、松树组织、海拔和季节对内生拟盘多毛孢定殖率、Shannon-Weiner指数和相似性指数的影响。在此基础上,筛选对松落针病菌、烂皮病菌、赤枯病菌有拮抗作用的内生拟盘多毛孢,浸渍法检测其对松针的致病性,采用喷雾法和针刺法分别对室内盆栽湿地松苗接种拮抗菌和3种病原菌,计算发病率、病情指数和防治效果。【结果】湿地松、马尾松、火炬松中内生拟盘多毛孢的多样性明显高于华山松和云南松,内生拟盘多毛孢在针叶中的分布多于枝和干,其多样性在海拔较低地区(400~600 m)相对较高,不同季节则以春季多样性最高。此外,散沫拟盘多毛孢(P.lawsoniae)、小孢拟盘多毛孢(P.microspor)和石楠拟盘多毛孢(P.photiniae)对松落针病菌、松烂皮病菌、松赤枯病菌3种病原均有拮抗作用,抑制率达38.49%~77.42%,其中P.lawsoniae的作用最为明显,且在致病性测定中对松针无伤害作用。室内对湿地松苗病害的防治试验中,P.lawsoniae孢子原液及稀释液(50倍液和500倍液)对3种病害均表现出了较好的防治效果,防治效果达40.90%~89.77%。【结论】松树内生拟盘多毛孢资源丰富,对松树病害具有生物防治潜力,其中P.lawsoniae对松树落针病、烂皮病和赤枯病具有良好的生防前景。     

生防菌粗毒素对猪殃殃防御酶及叶片细胞膜透性的影响

为了揭示生防菌的致病机理,用3株生防菌粗毒素处理猪殃殃叶片,测定其过氧化氢酶(CAT)、超氧化物歧化酶(SOD)、过氧化物酶(POD)的活性、电导率和丙二醛(MDA)含量,探讨生防菌粗毒素对叶片防御酶活性及叶片细胞膜透性的影响。结果表明,3株生防菌粗毒素使猪殃殃叶片组织细胞膜透性上升,MDA含量上升;毒素处理后的猪殃殃叶片中POD、SOD和CAT的活性均较不处理的对照升高。     

Towards understanding the ecology and mechanisms of biocontrol of Clonostachys rosea IK726

Clonostachys rosea (syn. Gliocladium roseum) IK726 was originally selected as an effective biocontrol agent (BCA) against cereal seed borne diseases caused by Fusarium culmorum and Bipolaris sorokiniana. We have studied the efficacy of the antagonist against different pathogens in several crops and found that the antagonist also is able to control Alternaria radicina and A. dauci on carrot seeds and different cold-storage fungi in acorns. IK726 is also able to reduce…     

木霉对食用菌侵染能力的分析

研究了49株木霉对食用菌菌丝的侵染能力,结果显示:不同木霉的侵染能力不同,对食用菌侵染能力强的木霉对植物病原真菌的侵染能力并不一定强,表现出木霉对真菌侵染的特异性。木霉侵染食用菌的机理研究结果显示:木霉可通过溶壁、缠绕等方式作用于食用菌菌丝细胞壁,木霉发酵液对食用菌和植物病原菌都有很好的抑制作用,但木霉产几丁质酶的能力与木霉的侵染能力没有直接关系。     

Evaluation of Allorhogas pyralophagus Marsh (Hymenoptera: Braconidae) for the biological control of Diatraea spp. (Lepidoptera: Pyralidae) in sugar-cane in Guyana

In 1989, a mass production and field release programme of Allorhogas pyralophagus Marsh (Hymenoptera: Braconidae) for the control of the Diatraea spp., particularly D. centrella (Möschler) (Lepidoptera: Pyralidae) in sugar-cane, was initiated by the Guyana Sugar Corporation. The programme was terminated in 1995 after the release of approximately two million adult parasites resulted in a mean field parasitism in Diatraea spp. larvae of only 0.22%. In contrast, 62% of Diatraea spp. larvae were parasitised in vitro as were 32% of larvae in young cane shoots exposed to A. pyralophagus in the laboratory. Neither Diatraea larvae in young cane plants caged in the field nor those recovered from Echinochloa polystachya (Kunth) Hitchc. and Paspalum virgatum L. around release fields showed any parasitism by A. pyralophagus. The reasons for the low rate of host acquisition outside the laboratory are not known, but it is clear that A. pyralophagus offers little prospect for significant control of Diatraea spp., particularly D. centrella in sugar-cane in Guyana.     

放线菌在植病生防中的研究进展

综述了植物病害生物防治研究的意义,详细介绍了放线菌在植物病害生物防治中的拮抗机制及其生防作用,并对一些有关放线菌应用中的问题及解决途径进行了探讨.     

Actinobacteria-enhanced plant growth, nutrient acquisition, and crop protection: Advances in soil, plant, and microbial multifactorial interactions

Agricultural areas of land are deteriorating every day owing to population increase, rapid urbanization, and industrialization. To feed today’s huge populations, increased crop production is required from smaller areas, which warrants the continuous application of high doses of inorganic fertilizers to agricultural land. These cause damage to soil health and, therefore, nutrient imbalance conditions in arable soils. Under these conditions, the benefits of microbial inoculants (such as Actinobacteria) as replacements for harmful chemicals and promoting ecofriendly sustainable farming practices have been made clear through recent technological advances. There are multifunctional traits involved in the production of different types of bioactive compounds responsible for plant growth promotion, and the biocontrol of phytopathogens has reduced the use of chemical fertilizers and pesticides. There are some well-known groups of nitrogen-fixing Actinobacteria, such as Frankia, which undergo mutualism with plants and offer enhanced symbiotic trade-offs.In addition to nitrogen fixation, increasing availability of major plant nutrients in soil due to the solubilization of immobilized forms of phosphorus and potassium compounds, production of phytohormones, such as indole-3-acetic acid, indole-3-pyruvic acid, gibberellins, and cytokinins, improving organic matter decomposition by releasing cellulases, xylanase, glucanases, lipases, and proteases, and suppression of soil-borne pathogens by the production of siderophores, ammonia, hydrogen cyanide, and chitinase are important features of Actinobacteria useful for combating biotic and abiotic stresses in plants.The positive influence of Actinobacteria on soil fertility and plant health has motivated us to compile this review of important findings associated with sustaining plant productivity in the long run.     

皮尔瑞俄类芽胞杆菌ZF390对黄瓜细菌性软腐病的防治效果

针对黄瓜细菌性软腐病发生严重且难以防治的问题,本研究以活体防治效果为指标,筛选更加有利于田间应用的高效生防菌株。采用梯度稀释法分离纯化病害发生严重地块的健康黄瓜植株根际中的细菌菌株,再利用双层培养法筛选到6株黄瓜细菌性软腐病菌拮抗菌株,最终通过喷雾接种法筛选得到能够有效防治黄瓜细菌性软腐病的生防菌株ZF390,其防效可达77.94%,且该菌株能够有效抑制8种病原细菌的生长,抑菌谱广。结合形态学特征、生理生化特性和多位点序列分型分析,鉴定菌株ZF390为皮尔瑞俄类芽胞杆菌Paenibacillus peoriae。采用单因素试验对菌株ZF390摇瓶发酵工艺进行优化,最终发酵液菌体浓度提高了4个数量级,可达2.94×10⁹ CFU/mL。菌株ZF390是一株能够有效防治黄瓜细菌性软腐病的生防菌株,具有进一步开发成生防制剂的应用潜力。     

解淀粉芽胞杆菌JK10防治蓝莓根癌病的机理研究

本研究旨在揭示解淀粉芽胞杆菌JK10防治蓝莓根癌病的生防机制。利用改良发酵培养基对解淀粉芽胞杆菌JK10菌株进行发酵,用盐酸沉淀、硫酸铵沉淀、乙酸乙酯萃取、大孔树脂吸附四种方法对JK10发酵液中的活性物质进行分离,利用MALDI-TOF-MS对活性最高的粗提物进行分析明确其种类;对JK10进行绿色荧光蛋白标记,明确其在蓝莓根际土及组织内的定殖能力;使用高通量测序技术对蓝莓健康根组织、根癌病根组织及JK10处理的根癌病根组织内生细菌群落结构进行分析。结果表明,四种方法得到的粗提物对根癌土壤杆菌均有良好的拮抗效果,其中大孔树脂吸附法得到的粗提物抑菌活性与产率均最高。JK10发酵液中能检测出bacillomycin D和fengycin两类脂肽类化合物、大环内酯类抗生素Divergolide D和聚酮类化合物Bacillaene;菌株JK10能够稳定定殖于蓝莓根际土、蓝莓根组织细胞间隙和蓝莓叶中,定殖数量在接种35 d后趋于稳定,在蓝莓根际土和蓝莓叶中分别为1×10⁶、4.0×10⁵cfu/g;蓝莓根癌病根组织在施入生防菌JK10菌株后,相比自然条件下蓝莓根癌病根组织内生细菌菌落结构发生改变,物种多样性增加,结构更加趋向于健康蓝莓根组织内生细菌。综上所述,解淀粉芽胞杆菌JK10通过产生对蓝莓根癌病菌有抑制活性的物质,稳定定殖在蓝莓根际土及蓝莓根、叶组织中,改变蓝莓根内生细菌的群落结构而达到防治蓝莓根癌病的目的。