生防菌株哈茨木霉H-13固体发酵条件的研究

研究了生防菌株哈茨木霉H-13固体发酵的条件,探索了碳源、氮源、磷酸盐、固料比、接种量及发酵温度对产孢量的影响.通过单因素试验和正交试验确定固体发酵最佳条件为:麸皮、玉米粉按3∶1比例配伍,固料比水为 1∶0.4(g·mL-1),蔗糖1.5%,蛋白胨1.5%,硝酸铵1%,磷酸二氢钾0.05%,NaH2PO4 -Na2HPO4(0.5%～0.50%),接种量为9%(mL·g-1);发酵温度为24℃～22℃～26℃,在此条件下发酵10 d,产孢量高达1.0×1010个·g-1以上.固体发酵生产木霉分生孢子,与液体相比具有制作简单、成本低廉、孢子含量高、易于保存和运输等特点.     

Advances in biocontrol mechanism and application of Trichoderma spp. for plant diseases

Trichoderma spp.is a filamentous soil fungus known as an effective biocontrol agent of a range of important airborne and soilborne pathogens,it has universal distribution and economic importance.This article reviewed the researches on biocontrol mech- anism for plant diseases and application of Trichoderma spp.,especially Trichoderma harzianum in recent years.     

哈茨木霉Th-A和Th-B的存活力与定殖能力的测定

 哈茨木霉Th-A和Th-B的孢子存活力受温度、贮藏期和调理剂的影响,并随时间的延长孢子的存活力明显下降。在室温条件下贮藏60 d,Th-A和Th-B的孢子存活率分别达71.33%和73.33%,在4 ℃冷库里贮藏60 d,两菌株孢子存活率分别达90.00%和92.67%. 贮藏90 d时,室温下Th-A和Th-B的孢子存活率分别为14.00%和18.00%,在冷库中孢子存活率为46.67%和32.67%. 两个菌株与土壤调理剂混合时,在45 d时,冷库中孢子存活率基本没有变化,但在室温下存活率很低,仅5.77%～57.14%,60 d后,冷库和室温下存活率≤1%. 2个菌株在马铃薯根围中定殖能力随着施用后的时间延长而下降,但在140 d后,仍能检测到施入量的10%以上菌量,Th-A和Th-B比未施用木霉对照高出63.64倍和153.48倍。     

Construction of engineering Trichoderma strains and their characteristics against tomato gray mold

The transformed Trichoderma strains Ttrm31, Ttrm34 and Ttrm55 were obtained from Trichoderma wild strain T21 mutated by REMI technique for more effective biocontrol of tomato gray mold (Botrytis cinerea) with Trichoderma agent. Those transformants appeared much better in biocontrol activity in vitro or in vivo against tomato gray mold were better than that of wild strain T21. The main results were as follow: The transformed Trichoderma strains were detected in their genetic …     

Mechanisms involved in biocontrol and plant induced resistance by richoderma. asperellum (T. harzianum T-203)

Growing awareness of the environmental damage caused by the use of chemical substances for plant disease control in agriculture has raised the need to study biological alternatives, such as activating the defense response of plant crops by inducers not toxic to the environment. Trichoderma spp. are effective biocontrol agents for a number of soilborne pathogens, and are also known for their ability to enhance plant growth and to induce systemic resistance (ISR) in plants. In our laborator…     

三唑酮对豌豆根际木霉定殖和尖孢镰刀菌厚垣孢子萌发的影响

研究结果表明,微量三唑酮能有效提高木霉拮抗菌株在豌豆根际、根外土中的定殖能力木霉菌和三唑酮都能抑制根际和根外豌豆尖孢镰刀菌的厚垣孢子萌发,木霉菌的抑制作用较4μg土和6μg土三唑酮强,木霉菌和三唑酮结合可进一步抑制根际厚垣孢子的萌发。     

木霉菌防治烟草根腐病及其土壤优势微生物的相互作用

用施有100~200 g/667m2木霉菌的肥土包根假植后盆栽,可有效防治烟草镰刀菌根腐病、并有较好的治疗作用和促生效应,其中以150 g/667m2剂量的效果最好。对木霉菌与土壤和圈肥中的优势真菌、细菌、放线菌株相互作用研究的结果表明,木霉菌对土壤优势真菌和部分常见土传病原真菌有较强的抑制作用,在测定的3株优势细菌中,其中2株对木霉菌无抑制作用,但分别能抑制或促进木霉菌产孢;仅1株对木霉菌有不完全抑制作用,但对其产孢无影响。多数优势放线菌株对木霉菌生长或产孢都有一定抑制作用,但各菌株对土壤和病苗分离的病原茄病镰刀菌也有不同程度抑制作用。该结果证实,木霉菌在土壤中有较强的竞争能力,但其在土壤中的存活又受到多种土壤微生物的限制,同时也在一定程度上证实了应用木霉防治烟草病害的生态安全性。     

The ethics of biofungicides – A case study: Trichoderma harzianum ATCC 20476 on Elsanta strawberries against Botrytis cinerea (gray mold)

Trichoderma ATCC 20476 based biofungicides have been marketed continuously on a small scale for 20 years. A more recently developed application for these biofungicides is the treatment of strawberries against the gray mold Botrytis cinerea. That application is examined in terms of Lockwood's criteria for ethics in biological control. Unaddressed risks resulting from the current scramble for market share in northern Europe are pointed out.     

哈茨木霉(Trichoerma harzianum)T23生防菌筛选及防治中药材根腐病的研究

研究表明,引起麦冬、丹参、川芎等中药材根腐病的主要病原种群是尖孢镰刀菌及腐皮镰刀菌．为了有效防治中药材根腐病,保护环境,提高品质和产量,通过不同生态区的土样采集,采取病原菌诱饵法及稀释平扳法分离菌株,经筛选、纯化得到抑菌拮抗效果达80％以上的哈茨木霉生防菌T23;不同剂量试验结果表明,施用哈茨木霉T23生物制剂7．5kg／hm^2效果最佳,田间防治麦冬、丹参、川芎等中药材根腐病效果达70％以上,显著优于50％多菌灵粉剂,比对照增产14．2％～24．5％．大面积防治中药材根腐病的防病增产效果与田间小区试验的一致．     

拮抗木霉耐药性菌株的筛选及其与速克灵防治灰霉病的协同作用

通过试验表明,速克灵与拮抗木霉菌（Trichoderma spp）对防治灰霉病具有协同作用。经速克灵浓度对协同作用影响的研究发现,速克灵与木霉菌剂配比为10：80条件下,抑菌率最高5％,明显高于单独使用速克灵与拮抗木霉菌剂的效果。同时应用菌 药、药、菌1000倍液处理防治黄瓜灰霉病,防治效果分别为67.6％、62.5％、51.5％,较单独利用拮抗木霉菌防治降低了病原菌的侵染和致病力,并且减少了药剂的使用剂量。     

解淀粉芽孢杆菌B9601-Y2抗性基因标记及其在作物根部的定殖能力

以质粒pMarA转入解淀粉芽孢杆菌植生亚种B9601-Y2菌株,获得了卡那霉素抗性标记遗传稳定的菌株Y2-pMarA。采用浇灌法、拌种法和浸根法接种大白菜,并用浇灌法接种烟草,观察菌株在大白菜和烟草根部的定殖与消长动态。结果表明:通过10μg/mL卡那霉素的LB平板和PCR方法,证明标记菌株Y2-pMarA均能在植株根际、根表和根内定殖。在播种时浇灌大白菜37d后,在自然土处理中根际土、根表土和根内菌量分别为浇灌7d后菌量的94.31%、95.00%和84.75%,在灭菌土中则分别为75.26%、84.92%和177.74%;在拌种处理大白菜时,自然土处理中根际土、根表土和根内菌量分别为拌种7d后菌量的94.44%、95.27%和61.06%,在灭菌土处理中则分别为75.64%、90.91%和69.06%;在浸根10min后移栽,标记菌株能在大白菜根际土壤中扩散和进入根内;至移栽后33d,自然土处理中根际土、根表土和根内菌株定殖密度分别为6.28×105、9.54×105和4.69×103 cfu/g;灭菌土处理中则分别为6.97×105、1.12×106和1.02×104 cfu/g。