木霉生防菌对大豆幼苗的促生作用及对根腐病的防治效果

[目的]研究木霉菌对大豆幼苗的促生作用及对根腐病的防治效果。[方法]用6株木霉菌剂处理土壤进行盆栽试验,测定大豆植株的形态指标及根腐病的发生情况。[结果]供试木霉菌株均能促进大豆植株生长,其株高、茎粗、根长、干物质积累均比对照增加。木霉菌株制剂均可减轻根腐病的发生,当浓度为5×108个/g时,防效均在70%以上。不同菌株对大豆植株的促生和对根腐病的防治效果不同。[结论]木霉菌能促进大豆的生长和降低根腐病的发生。     

Identification of novel Trichoderma hamatum genes expressed during mycoparasitism

Trichoderma species are currently used as biocontrol agents for crop diseases caused by a number of fungal plant pathogens. However, their biocontrol performance in the field can be unreliable and it is likely that more consistent performance could be achieved through knowledge and manipulation of the genes involved. For example, induction of the genes could be optimised for variable environmental and physiological conditions, superior strains could be selected more effectively and novel st…     

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.     

Screening of Trichoderma strains tolerant to benzimidazole

The screening of isolates and the assay of biocontrol mechanisms of Trichoderma were studied systematically in laboratory and greenhouse in vivo. The proteins tolerant to benzimidazole in Trichoderma strains were purified, and their physical and chemical properties were detected. Compared their biological activities in vitro and vivo in greenhouse, nine biocontrol strains (including Ty-10-2,LTR-2,Tj-5-1,Tj-5-4,Ty-11-1,Tj-11-3,Ty-11-3,Tj-3-3-2,Tj-3-3-4) were screened. These bioco…     

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 …     

Genetic regulation of conidiation in Trichoderma hamatun

Achieving a balance between vegetative growth and spore production is essential for successful biocontrol by fungi. Low sporulation rates in the field can result in poor establishment and survival,whereas failure of conidia to recognise hosts can lead to persistence without efficacy. Commercial biocontrol products involve bulk preparations of conidia, however considerable variability in conidiation rates exists between biocontrol agents, which can restrict choice of strain for production. The majority of studies on Trichoderma conidiation have focused on the species T. viride and T. atroviride.These species form conidia in response to blue and near-UV light and/or nutrient deprivation and conidiation proceeds in a highly co-ordinated fashion, however relatively little is known on the genetic basis of Trichoderrma conidiation. In addition, whilst photoconidiation appears to be a general response detailed studies in other Trichoderma species are absent. In this study, conidiation in the lesser known biocontrol species T. hamatum is being investigated using a combined morphological and molecular approach. In contrast to T. atroviride, conidiation in response to blue-light was weaker and variable and suggested that additional triggers may be required for the T. hamatum photoresponse. A series of comparative photoconidiation assays are currently being undertaken investigating the effect of inoculum type and abiotic factors on timing and intensity of the response.Results will be discussed in relation to the current knowledge on conidial morphogenesis in Trichoderma. In addition to these morphological assays, a selection of genes implicated in sporulation and the blue-light responses are currently being isolated and characterised from T. hamatum. Two genes, phr1 and cmp1 , which were isolated previously from T. atroviride will be used as early and late markers of gene expression during the photoresponse in T. hamatum in order to define time points for harvesting comparable stage-specific RNA from T. hamatum and T. atroviride. Using degenerate PCR putative sporulation gene orthologues have also been identified in T. hamatum.Work is currently underway to isolate genomic clones of these genes from T. hamatum and T.atroviride. Sequence and expression analysis of orthologues, including expression in response to abiotic factors will be presented and discussed in relation to the current knowledge of the molecular basis of conidiation in Trichoderma and other filamentous fungi.……     

Diversity of Trichoderma in greenhouse soil

The protected agricultural production has become one of the fast growing and wid espread cultivation technology in the north parts of China. Continuous cultivati on of single crop or less rotation of crops usually resulted in the large amount of accumulation of soilborne pathogens and serious crop diseases in the greenho use. After a few years of investigation of soilborne fungi in the north parts of China, nearly one hundred species of mictosporic fungi have been identified by the authors.…     

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．     

Functional genomic approach to the study of biodiversitywithin Trichoderma

Trichoderma is a fungal genus of great and demonstrable biotechnological value, but its genome is poorly surveyed compared with other model microorganisms. Due to their ubiquity and rapid substrate colonization, Trichoderma species have been widely used as biocontrol organisms for agriculture, and their enzyme systems are widely used in industry. Therefore, there is a clear interest to explore beyond the phenotype to exploit the underlying genetic systems using functional genomics tools. Th…     

钩状木霉在辣椒根际定殖动态及其对辣椒疫病的生物防治

木霉菌（Trichoderma spp.）是自然界广泛分布的一类重要生防真菌资源。生防菌在宿主根际及其组织中定殖能力的强弱是评价其生防潜力的重要指标。选择钩状木霉（Trichoderma hamatum）真菌、辣椒及其重要土传病害菌辣椒疫霉（Phytophthora capsici）三者互作体系，通过绿色荧光蛋白标记的钩状木霉菌株灌根接种辣椒植株，通过平板拮抗试验和温室盆栽试验，检测钩状木霉菌在辣椒植株及根际的定殖情况，及其对辣椒疫病的生物防治效果。结果表明，钩状木霉菌在辣椒根、茎和叶等组织中和辣椒根际土壤中均能够定殖。在辣椒根际土壤中，钩状木霉菌呈动态变化的定殖过程。灌根接种1～25 d，钩状木霉菌定殖量呈缓慢增长，在第33 d，达到最高值(700×107 conidia·g-1)，然后逐渐下降，呈现先增加后减少的动态变化过程。钩状木霉菌在辣椒根际和植株的定殖过程中，对辣椒疫病具有生物防治作用，防治效果达到5333％。综上，钩状木霉菌能够成为辣椒根际微生态中的有益微生物，可以有效预防辣椒疫病的发生，研究为辣椒疫病的生物防治提供了理论依据和有效途径。     

绿色木霉改良菌株在蔬菜生产中的应用研究

[目的]明确绿色木霉不同菌株间、绿色木霉与化学农药间的相互作用,探讨绿色木霉的使用方法和使用量。[方法]利用平板试验、盆栽试验、大棚试验对绿色木霉的应用技术进行研究。[结果]将经遗传改良的绿色木霉W512、R6、R31、R65、L2用于蔬菜生产。在20～30℃环境温度,10^7～10^8孢子浓度下,对蔬菜立枯病（灌根）、白粉病等可以取得90%的生防效果;当环境低于20℃,建议以化学防治为主。R65和L2在大棚蔬菜上的生防效果较好。[结论]经过遗传改良的绿色木霉菌株在适当的使用方法下可以取得较好的生防效果。     

木霉菌对番茄灰霉病菌的抑制作用

为明确木霉菌对福建省番茄灰霉病菌的抑制效果,研究了8株木霉菌对病原菌的拮抗作用。结果表明,在对峙培养条件下,供试木霉菌能显著抑制灰霉病菌菌丝生长,其抑制率为86.83%~91.39%,不同木霉菌株的发酵液对病原菌菌丝生长具有不同程度的抑制效果,其差异达显著水平。其中,菌株FJ2006-8发酵液的抑制生长率最高,为39.44%。此外,供试的木霉菌均能产生非挥发性和挥发性代谢产物,其中,菌株FJ2006-8的非挥发性代谢产物对病原菌菌丝生长的抑制效果最佳,抑制率为61.09%;而菌株T05-58的挥发性代谢产物对病原菌菌丝生长的抑制率最高,为22.95%。研究结果可为木霉菌生防菌剂的开发以及番茄灰霉病的绿色防控提供理论依据。     

防治油菜菌核病的木霉和粘帚霉菌株筛选及生防的初报

2002年6月至12月中旬,用4批共200颗菌核作诱饵,分离到粘帚霉(Gliocladiumspp.)、木霉(Trichoderma spp.)、镰刀菌(Fusariumspp.)、青霉(Penicilliumspp.)、毛霉(Mucorspp.)、根霉(Rhizopusspp.)、曲霉(Aspergillus spp.)、腐霉(Pythiumspp.)和少量难鉴定菌株,共计171个菌株,其中粘帚霉80株、木霉55株,分别占46.8%和32.2%,在不同采样期内均为优势种群。所诱捕的木霉经鉴定分为7个种,哈茨木霉和康氏木霉出现较早,而黄绿木霉和拟康氏木霉出现较迟。通过测定所获得木霉菌株对核盘菌的拮抗作用,筛选出Tk1、Th2生防潜能较好的菌株。经离体叶片测定,Tk1和Th2对油菜菌核病的防治效果分别达90.6%和89.1%。     

木霉生防耐药因子的诱导及其生化特性研究

为了研究以含药(施佳乐)培养基筛选和诱导生防木霉菌株T-21产生耐药性生防蛋白因子———几丁质酶的效果。利用含药(施佳乐)培养基筛选诱导生防木霉菌株T-21产生几丁质酶,通过DEAE 32纤维素柱层析法进行分离纯化,用SDS-PAGE测定其分子量,并分析温度和pH值对酶活力的影响以及耐药酶对灰霉菌的抑制作用。生防木霉菌株T-21对化学农药施佳乐具有一定的抗性,浓度达1 000μg/ml时生长及产孢情况良好。通过分离纯化的几丁质酶,其分子量为45 kD,其最适反应温度为50℃,最适pH值为5.0,对灰霉菌有明显抑制作用。生防木霉菌株T-21产生的几丁质酶,可与化学杀菌剂混合使用,以增强田间的防治效果、减少化学农药的用量,进而减少化学农药对农作物的污染及残留。     

木霉的营养生长及发酵条件

 木霉是一类分布广泛的土壤习居菌,而且对一些病原真菌有很大的生防潜力。大部分木霉对营养的需求并不十分严格,可以分解利用纤维素、半纤维素、几丁质等多种多聚物作为其生长的碳源物质,也可以利用多种简单的和复杂的氮源化合物生长。为了应用木霉防治真菌病害,研究者摸索了各种培养条件,以求在低成本的前提下获得高的培养产物。其中包括应用糖蜜、麦麸、植物秸杆、虫草头孢废液和玉米粉等进行的固体培养、液体培养和固液两相培养,为大规模工业化生产奠定了一定的基础。     

木霉与土壤生态环境关系研究综述

木霉是土壤真菌中的重要群落,在植物根际分布非常广泛,是一种很有应用价值的植物生防菌。从土壤生态环境对木霉的影响和木霉对土壤的修复作用,对木霉与土壤生态环境的关系展开论述,并对土壤木霉的应用进行了展望。     

Are mycoparasitism and chitinase production species or isolate dependent in Trichoderma ?

The relationship between taxonomic status of Trichoderma spp., chitinase production in solid substrate fermentation (SSF) on four media and mycoparasitism in dual culture (confrontation assay)against four plant pathogenic fungi was studied. Seventy five Trichoderma isolates belonging to 35species have been screened. The plant pathogenic fungi used in confrontation assay were Botrytis cinerea , Fusarium oxysporum f. sp. dianthi , Rhizoctonia solani and Sclerotinia sclerotiorum . The SSF media contained wheat bran, crude chitin (from crab shells, SIGMA) and salt solutions. The best performing isolates in mycoparasitism tests were Trichoderma flavofuscum, T. harzianum, T.inhamatum, T. koningii and T. strigosum. Some isolates exhibiting good mycoparasitism produced chitinase in SSF only at low or medium level. In contrary there were isolates with excellent extracellular chitinase production but their biocontrol potential did not belong to the leading group.Statistical methods have been used to evaluate the data.……     

木霉菌防治烟草黑胫病研究进展

黑胫病是烟草生产上的重要土传病害之一,广泛分布于各个烟草种植区。综述了利用木霉菌防治烟草黑胫病的菌株筛选、防治效果、拮抗机制的最新进展,为烟草黑胫病的生物防治提供了参考。     

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…     

放线菌327~#代谢产物对木酶的抑制作用

为探索利用拮抗菌防治由木霉引起的食用菌病害,以对多种植物病原菌有抑制作用的放线菌327#为供试材料,研究其对木霉的抑制效果和作用方式,以及对白灵菇生长的影响。结果表明:放线菌327#无菌发酵滤液对木霉菌丝生长有较强的抑制作用,培养7d,含327#发酵滤液的琼脂周围木霉无法生长。琼脂扩散试验中,发酵滤液在含木霉孢子的平板上可形成直径(20±1)mm的抑菌圈,圈内木霉孢子萌发受到强烈抑制。浓度为10%的发酵滤液使木霉菌丝停止发育,不能形成孢子。而327#发酵滤液对白灵菇的生长影响较弱,培养7d,含327#滤液的琼脂周围白灵菇可生长。由此可见,拮抗放线菌327#的代谢产物对木霉有较强抑制作用,而对白灵菇的影响不大。