A transcriptomic database was constructed to study the biocontrol mechanisms of Trichoderma harzianum ACCC30371 using high quality UniGenes following growth in eight culture media[(1/2PD,minimal medium MM(containing d...A transcriptomic database was constructed to study the biocontrol mechanisms of Trichoderma harzianum ACCC30371 using high quality UniGenes following growth in eight culture media[(1/2PD,minimal medium MM(containing dextrose 10 g L^-1),C starvation medium(derived from MM without dextrose),N starvation medium(derived from MM without ammonium sulphate),and four kinds of phytopathogenic fungi cell wall media].A 4 Gbp transcriptome was generated and 96.7%of the database had a sequencing error rate less than 1%.A total of 25,013 UniGene sequences were obtained with a mean length of 1135 nt.There were 2571 sequences longer than 3000 nt.The National Center for Biotechnology Information Accession number of this transcriptome is SRR8382572.There were 16,360 Unigenes annotated to the Nr protein database,9875 to the SwissProt database,10,266 to the KEGG database,7164 to the COG database,and 1508 to the GO database along with their protein functional annotations.There were 16,723 functional genes identified.We identified 402 bio-control genes,including 14 related to competition,311 to mycoparasitism,76 to antibiosis,and one related to eliciting a plant response.This shows that T.harzianum ACCC30371 has integrated biocontrol mechanisms,and of these mechanisms,mycoparasitism is the most prevalent.Antibiosis and induced systemic resistance also play important roles.These results provide a foundation for further research into the biocontrol mechanisms of Trichoderma,as well as the development and utilization of biological fungicides.展开更多
Biocontrol by Trichoderma has been studied mainly with selected isolates of T. harzianum, T. atroviride and T. asperellum, which are members of sections Pachybasium and Trichoderma. In contrast, species from section L...Biocontrol by Trichoderma has been studied mainly with selected isolates of T. harzianum, T. atroviride and T. asperellum, which are members of sections Pachybasium and Trichoderma. In contrast, species from section Longibrachiatum have only rarely been studied. On the other hand, one taxon from this section-Hypocrea jecorina (anamorph: Trichoderma reesei)-has been widely used for the production of cellulolytic and hemicellulolytic enzymes and recombinant proteins. As far as Trichoderma is concerned, molecular genetic methods and tools are most advanced in H. jecorina, and its genome has recently been fully sequenced, thus making this taxon a model organism for the genus. Here we will demonstrate that H. jecorina is able to antagonize plant pathogenic fungi in plate confrontation tests, and can protect tomato and cucumber plants against Pythium ultimum blight. Using this as a model case, we made use of available H. jecorina mutants to investigate (a) whether carbon catabolite repression via the Cre1-regulator protein has an impact on biocontrol, and (b) whether cellulase gene expression is necessary for biocontrol of P. ultimum. In the first case, plate confrontation tests and in planta experiments yielded opposite results, i.e. while a Cre1 mutant was more active in antagonization of fungi on plates, the survival rates of P. ultimum-inoculated cucumber plants was lower than with the H. jecorina wild-type strain. Mutants of H. jecorina, unable to form cellulases, were still able to antagonize fungi on plates and provided similar protection of tomatos against P. ultimum as the wild type, indicating that the pronounced biocontrol ability of H. jecorina against fungi with cellulose-containing cell-walls is not due to its high cellulolytic activity. A strain disrupted in the light-modulator gene envoy (Schmoll et al., ms submitted) exhibited in planta biocontrol activity strongly exceeding that of the wild-type strain, thereby providing a first link between Trichoderma biocontrol and light. In view of the numerous other metabolic and regulatory mutants of H. jecorina available, we suggest that this fungus should increasingly be used in basic studies on the biochemistry and genetics of biocontrol.展开更多
Biocontrol agents are safe and environmental friendly alternatives for pesticides in agriculture application. Trichoderma viride WEBL0703 performed a high level of antagonistic activity toward a broad spectrum of phyt...Biocontrol agents are safe and environmental friendly alternatives for pesticides in agriculture application. Trichoderma viride WEBL0703 performed a high level of antagonistic activity toward a broad spectrum of phytopathogens and was determined as a biocontrol agent, which was produced by solid state fermentation using grape marc and wine lees. The maximum yield of T. viride conidia was up to 6.65 × 10^9 CFU/g initial dry substrate (IDS) after 10 d fermentation. As important enzymes for protecting plants from disease, chitinase, β-glucanase, and pectinase yields were 47.8 U/g IDS, 8.32 U/g IDS and 9.83 U/g IDS, respectively. These results show that it is feasible to convert winery wastes to a value-added and environmental friendly biocontrol agent.展开更多
Streptomyces rubrogriseus HDZ-9-47,isolated from eggs of Meloidogyne spp.,was evaluated as a potential biocontrol agent of Meloidogyne incognita under in vitro and protective field.Microscopic observations showed that...Streptomyces rubrogriseus HDZ-9-47,isolated from eggs of Meloidogyne spp.,was evaluated as a potential biocontrol agent of Meloidogyne incognita under in vitro and protective field.Microscopic observations showed that HDZ-9-47 parasitized eggs of M.incognita within 7 days.In vitro,the culture filtrate of HDZ-9-47 caused 97.0%mortality of second-stage juveniles(J2s)of M.incognita and inhibited more than 50%egg hatching.In the field,compared with the control,the rootknot index and J2s density in the treatment of drench the broth contained 1012 HDZ-9-47 spores were respectively reduced by 51.1 and 80.7%at 90 days post transplantation,which were better than that in other application doses and methods.In addition,reduction rates of root-knot index and J2s density of the treatment of combined application of HDZ-9-47 with biofumigation was 87.1 and 91.0%,respectively,better than either of HDZ-9-47 or biofumigation used alone or fosthiazate treatment.And tomato yield also increased by 16.1%.Together,our results suggest that HDZ-9-47 could be an effective biocontrol agent of M.incognita,and that application of HDZ-9-47 combined with cabbage residue biofumigation was a promising and sustainable option for M.incognita control.展开更多
Several bacterial strains were isolated from different rhizospheres. Among these, strain PDY7 exhibited strong antibacterial activity against the rice bacterial blight (BB) pathogen Xanthomonas oryzae pv. oryzae (...Several bacterial strains were isolated from different rhizospheres. Among these, strain PDY7 exhibited strong antibacterial activity against the rice bacterial blight (BB) pathogen Xanthomonas oryzae pv. oryzae (Xoo) by the laboratory dual plate assays. The antibacterial property of the strain PDY7 was further investigated for the production of 2,4-diacetylphloroglucinol (DAPG), which amplified a characteristic of 629-bp DNA fragment by PCR-based screening method using phlD primers. The application of phlD positive strains was carefully evaluated for disease control and growth promotion of rice plants under field conditions. The selected strain PDY7 suppressed the rice BB by 58.83% and 51.88% under glass house and field conditions, respectively. In addition, the strain PDY7 showed significant two-fold increase in root length (18.08 cm), shoot length (29.81 cm), and grain yield (96.07 g). Strain PDY7 promoted the growth of rice plants by production of indole-3-acetic acid (IAA), which was determined by high performance liquid chromatography (HPLC) analysis. Our findings suggest that PDY7 belongs to the P. fluorescens group and can serve as potential biocontrol of BB as well as biofertilizer agent for growth promotion of rice.展开更多
Modern agribusiness plays a vital role in safeguarding and improving the production,quality,and quantity of food,feed,fiber,and fuel.Growing concerns over the impact of chemical pesticides on health and the environmen...Modern agribusiness plays a vital role in safeguarding and improving the production,quality,and quantity of food,feed,fiber,and fuel.Growing concerns over the impact of chemical pesticides on health and the environment have stimulated the industry to search for alternative and greener solutions.Over the last years,the RNA interference(RNAi)process has been identified as a very promising new approach to complement the arsenal of foliar spray,soil,or seed treatments applied as chemical and biological pest control agents,and of plant-incorporated protectants(PIPs).RNA-based active ingredients(AIs)possess a unique mode of action and can be implemented via both genetic modification(GM)and biocontrol approaches.RNA-based AIs promise to deliver the selectivity and sustainability desired in future crop protection agents.This is due to their utilization of a natural process to exert control and their high level of selectivity,which leads to reduced risk for non-target organisms(NTOs).This review discusses the advantages and limitations of RNA-based solutions in crop protection and recent research progress toward RNA-based biocontrols against the Colorado potato beetle(CPB),corn rootworm(CRW),and soy stink bug(SSB).Many challenges still exist on the road to the implementation of a broad range of RNA-based products and their widespread use and application.Despite these challenges,it can be expected that RNA-based AIs will become valuable new tools complementing the current arsenal of crop-protection solutions.展开更多
Bacillus thuringiensis Bt185 and its insecticidal spectrum-expanded engineering strains are considered as potential biocontrol agents to soil insect Holotrichia parallela,Holotrichia oblita or Anomala corpulenta.Here ...Bacillus thuringiensis Bt185 and its insecticidal spectrum-expanded engineering strains are considered as potential biocontrol agents to soil insect Holotrichia parallela,Holotrichia oblita or Anomala corpulenta.Here we reported the complete genome of strain Bt185,it harbors eight plasmids,and plasmid p BT1850294 carries three cry8 genes.展开更多
Methicillin-resistant Staphylococcus aureus (MRSA) is among the most alarming pathogens affecting both humans and the global bovine industry. The current control measures in hospitals and on farms for MRSA have proven...Methicillin-resistant Staphylococcus aureus (MRSA) is among the most alarming pathogens affecting both humans and the global bovine industry. The current control measures in hospitals and on farms for MRSA have proven to be inadequate leaving a need for new rapid control methods to curb MRSA infections in situ. New control measures for bacterial infection are widely sought, with particular interest in the applications for bacteriophages (phages) as a biocontrol or therapeutic agent. The current study uses a wild highly lytic phage isolated from cow’s milk taken from three farms in Baghdad, Iraq. The resulting phage was able to rescue 100% of the mice from a median lethal dose (LD50) or (1 × 108 CFU mL-1 per mouse) for MRSA wild isolates achieved when the phage: bacteria ratio was 100:1. Even when treatment was delayed for 6 h post lethal infection, to the point where all mice were moribund, 80% of them were rescued by a single injection of this phage preparation. Based on the current results, a comprehensive study is needed to guide further research on the MRSA phage as a biocontrol for MRSA mastitis in dairy cows to replace or reduce the use of antibiotics in animal husbandry.展开更多
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 review...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 mechanism for plant diseases and application of Trichoderma spp., especially Trichoderma harzianum in recent years展开更多
This study investigates the biocontrol potential of Trichoderma asperellum mutants against Rhizoctonia solani, Alternaria alternata, and Fusarium oxysporum and growth promotion of Populus davidiana 9 P. alba var.pyram...This study investigates the biocontrol potential of Trichoderma asperellum mutants against Rhizoctonia solani, Alternaria alternata, and Fusarium oxysporum and growth promotion of Populus davidiana 9 P. alba var.pyramidalis(Pd Pap poplar) seedlings. A T-DNA insertion mutant library of T. asperellum was constructed using Agrobacterium tumefaciens-mediated transformation.Sixty-five positive transformants(T1–T65) were obtained.Growth rates of the mutants T39 and T45 were the same,39.68% faster than the WT. In toxin tolerance tests, only T39 had greater tolerance to A. alternata fermentation broth than the WT, but mutant T45 had the same tolerance as the WT to all fermentation broths. Furthermore, T39 and T45 had a greater antagonistic ability than the WT strain against R. solani and A. alternata. The inhibition rate of the mutants T39 and T45 against A. alternata are 73.92% and80.76%, respectively, and 63.51% and 63.74%, respectively. Furthermore, the three strains increased the activities of superoxide dismutases, peroxidase, catalase(CAT)and phenylalanine ammonia lyase(PAL) in Pd Pap seedling leaves. CAT and PAL activity in the Pd Pap seedling leaveswas 11.25 and 5.50 times higher, respectively, in the presence of T39 than in the control group and 12 and 6.35 times higher, respectively, in the presence of T45 than in the control group. All three strains promoted seedling growth and the root and stem development, especially mutant T45. Mutants T39 and T45 reduced the incidence of pathogenic fungi in poplar and stimulated poplar seedling growth.展开更多
The“oil stain disease”has become a phytosanitary status that involves economic losses for farmers who produce gulupa(Passiflora edulis Sims).For this reason,this research aimed to evaluate the biocontrol activity of...The“oil stain disease”has become a phytosanitary status that involves economic losses for farmers who produce gulupa(Passiflora edulis Sims).For this reason,this research aimed to evaluate the biocontrol activity of Bacillus subtilis ATCC 55033 in a culture medium based on fermented millet as a biocontrol product of the disease.Initially,metabolite production of seven strains of B.subtilis and a reference strain B.s(ATCC 55033)was evaluated;in addition,the in vitro antagonistic ability was evaluated against Xanthomonas axonopodis.Two experiments were performed under in vitro conditions:(1)study of the presence of halos of hemolysis due to metabolite production;(2)analysis of the antagonistic ability by using double layer.It was observed that concerning the average,a number five times bigger of halos of hemolysis and 10 times bigger halos of inhibition in vitro on the growth of X.axonopodis in the strains B.s(ATCC 55033)and B.s TB2 over other strains.Subsequently,the evaluation was performed under greenhouse conditions,based on a randomized block design,in which two treatments were applied over the soil:(1)application of the fermented medium based on millet with B.s ATCC 55033,24 h before X.a inoculation;(2)application of 5 d post-inoculation.It was observed that the treatment,previous infective process,obtained an average percentage of severity equal to 42.044%.In addition,after the evaluation month,a foliage restoration was presented.In conclusion,it is suggested that these products could act as inducers in the plant systemic resistance to trigger defense responses to infection of X.a.展开更多
Fungi and bacteria as insecticides have been tested to control forest pests for more than ten years, they are the saine kind of biocontrol agent with the different conentrations. thesame kind of the biocontrol agent w...Fungi and bacteria as insecticides have been tested to control forest pests for more than ten years, they are the saine kind of biocontrol agent with the different conentrations. thesame kind of the biocontrol agent with the different origin areas, and the mixtures of the different kinds of biocontrol agents. The infection mechanism of virus was discussed. moreover. the mfluence of these biocontrol agents on the small animals was also evaluated.展开更多
The increasingly strict regulation of the use of phytosanitary products and the will of the populations to move towards sustainable development allow bio-sourced products and more particularly for biocontrol in the fi...The increasingly strict regulation of the use of phytosanitary products and the will of the populations to move towards sustainable development allow bio-sourced products and more particularly for biocontrol in the field of pesticides to progress. The study carried out here concerns the evaluation of the potency of Bacillus amyloliquefaciens Bc2 and Trichoderma harzianum to fight against strawberry cultures infected with anthracnose (Fragaria × ananassa Duch.). The studies were carried out in the laboratory and in the field. The results indicate that B. amyloliquefaciens Bc2 and Trichoderma harzianum TR are effective for the biological control of anthracnose, gray mold and powdery mildew on strawberries grown in field conditions. The increase in plant size and the number of fruits produced with these control agents has also been observed.展开更多
Two antagonistic yeasts, Thichosporon pullulans and Cryptococcus laurentii, were investigated for their biocontrol potential to blue mold rot and rhizopus rot on harvested peach fruits(Prunus persica L. Batsch, cv. Ok...Two antagonistic yeasts, Thichosporon pullulans and Cryptococcus laurentii, were investigated for their biocontrol potential to blue mold rot and rhizopus rot on harvested peach fruits(Prunus persica L. Batsch, cv. Okubao), alone or in combination with a low dose of iprodione(50 μg ml-1). The results indicated that T. pullulans and C. laurentii were effective at reducing disease incidence and severity of blue mold rot and rhizopus rot in peach fruits. Biocontrol efficacy of C. laurentii and T. pullulans were significantly enhanced by combination with a low dose of iprodione(50 μg ml-1)against blue mold and rhizopus rot in peach fruits. T. pullulans and C. laurentii combined with a low dose of iprodione(50 μg ml-1)resulted in better disease control than either iprodione or the yeasts used alone. Dipping fruits in suspensions of antagonist cells showed the similar control effect as the treatment with iprodione(500μg ml-1).展开更多
This study was to evaluate the ecological risk of strain E26 (Agrobacterium sp.) by detecting its survival in waters and its effects on rhizosphere microorganisms. The data showed that E26 could not be detected in dis...This study was to evaluate the ecological risk of strain E26 (Agrobacterium sp.) by detecting its survival in waters and its effects on rhizosphere microorganisms. The data showed that E26 could not be detected in distilled water, tap water, river water, and rainwater after 36, 36, 8, and 9 days, respectively. E26 did not reveal significant effects on the population of bacteria, fungi, and actinomyces in rhizosphere soil and on the root surface of grapevines.展开更多
Bipolaris sorokiniana is an important disease causing wheat root rot. Different biocontrol strains were screened with the pathogen as the target. A total of 210 strains of bacteria and fungi preserved in the laborator...Bipolaris sorokiniana is an important disease causing wheat root rot. Different biocontrol strains were screened with the pathogen as the target. A total of 210 strains of bacteria and fungi preserved in the laboratory were preliminarily and secondarily screened by plate confrontation culture. The 17 strains of bacteria and 36 strains of fungi with good bicontrol effect were screened. Eventually, the best fungal strain and the best bacterial strain were obtained. The ITS fragments of fungi were amplified by PCR, and the target band of 571 bp was obtained. The 16 S gene frag-ments of bacteria were amplified by PCR, and the target band of 1 455 bp was obtained. Through morphological observation, the screened strains were identified. Finally, the bicontrol fungus was confirmed as Trichoderma asperellum and the bacterium was Bacillus amylofaciens.展开更多
The present study evaluates the possible modes of action of antagonistic bacteria and their tolerance to UV radiation, temperature and osmotic stress. The partial 16S-23S rRNA gene sequencing of eight antagonistic bac...The present study evaluates the possible modes of action of antagonistic bacteria and their tolerance to UV radiation, temperature and osmotic stress. The partial 16S-23S rRNA gene sequencing of eight antagonistic bacteria had a high match with three bacterial genera: <em>Curtobacterium</em>, <em>Pantoea</em> and <em>Bacillus</em>. In this study, the three <em>Bacillus</em> isolates showed the most relevant production of enzymes, volatile organic compounds and antibiosis against <em>Exserohilum turcicum</em>. Respect to UV radiation and temperature <em>Pantoea</em> and <em>Bacillus</em> isolates were more tolerant;whereas the eight isolates were tolerant to osmotic stress in varying degree. The three <em>Bacillus</em> isolates have the greatest potential as biocontrol agents for foliar diseases in maize. The antagonistic action could be explained through different modes of action such as enzymes, volatile organic compounds and/or direct antibiosis by other secondary metabolites. <em>Bacillus</em> isolates tolerance to environmental stresses including UV radiation, temperature and osmotic stress is relevant for survival and persistence on the leaf surface. This work provides new information about the mode of action of antagonistic bacteria with proven efficacy against maize leaf pathogens. In addition, it provides information about the tolerance of antagonistic bacteria against different stress conditions. The data of the present study could contribute to the development of a successful foliar biofungicide.展开更多
[Objectives]The paper was to study the toxicity of 9 biocontrol microbial products to adult population of Lasioderrma serricorne.[Methods]Nine biocontrol microbes were used as test materials to study their toxicity to...[Objectives]The paper was to study the toxicity of 9 biocontrol microbial products to adult population of Lasioderrma serricorne.[Methods]Nine biocontrol microbes were used as test materials to study their toxicity to the experimental population of L.serricorne adults.[Results]The toxicities of these biocontrol microbes from low to high at 5 d post spraying were:Luhai Beauveria bassiana powder(LC_(50)=462.752×10^(8) spores/L),Meichongzhi B.bassiana powder(LC_(50)=9713.157×10^(8) spores/L),Yiqiang Bio B.bassiana powder(LC_(50)=11203.321×10^(8)spores/L),Nongbao Bio B.bassiana powder(LC_(50)=12188.866×10^(8) spores/L),Yeshengwang B.bassiana powder(LC_(50)=21685.532×10^(8) spores/L);Fatu Bacillus thuringiensis suspension(LC_(50)=1.0844×10^(8) IU/L),Laojite B.thuringiensis suspension(LC_(50)=2.056×10^(8) IU/L),Lujinwa B.thuringiensis powder(LC_(50)=2.273×10^(8) IU/L),Nongbao Bio B.thuringiensis powder(LC_(50)=18.399×10^(8) spores/L).The toxicities of these biocontrol microbes from low to high at 10 d post spraying were:Nongbao Bio B.bassiana powder(LC_(50)=0.072×10^(8) spores/L),Yiqiang Bio B.bassiana powder(LC_(50)=2.484×10^(8) spores/L),Luhai B.bassiana powder(LC_(50)=44.551×10^(8) spores/L),Meichongzhi B.bassiana powder(LC_(50)=96.447×10^(8) spores/L),Yeshengwang B.bassiana powder(LC_(50)=723.347×10^(8) spores/L);Lujinwa B.thuringiensis powder(LC_(50)=0.0001×10^(8) IU/L),Fatu B.thuringiensis suspension(LC_(50)=0.045×10^(8) IU/L),Laojite B.thuringiensis suspension(LC_(50)=0.0644×10^(8) IU/L),Nongbao Bio B.thuringiensis powder(LC_(50)=1.899×10^(8) spores/L).The toxicities of these biocontrol microbes from low to high at 15 d post spraying were:Meichongzhi B.bassiana powder(LC_(50)=0.001×10^(8) spores/L),Nongbao Bio B.bassiana powder(LC_(50)=0.01×10^(8) spores/L),Yiqiang Bio B.bassiana powder(LC_(50)=0.084×10^(8) spores/L),Luhai B.bassiana powder(LC_(50)=2.370×10^(8) spores/L),Yeshengwang B.bassiana powder(LC_(50)=8.915×10^(8)spores/L);Lujinwa B.thuringiensis powder(LC_(50)=0.16×10^(4) IU/L),Laojite B.thuringiensis suspension(LC_(50)=0.185×10^(4) IU/L),Fatu B.thuringiensis suspension(LC_(50)=32.211×10^(4) IU/L),Nongbao Bio B.thuringiensis powder(LC_(50)=1590×10^(4) spores/L).[Conclusions]According to the three stages of tube rubbing,it is found that the control effects of Lujinwa B.thuringiensis powder and Meichongzhi B.bassiana powder are the best,and the results will provide technical support for the biological control of L.serricorne adults.展开更多
The quantity of bio-laboratories and bio-factories in Uzbekistan increases every year.In 1970,there were only 4,in 1971,16,in 1985,710,in 1990,774,and in 2000,790.At present there
Our study consists of a careful literature review carried out with the aim of better understanding the models developed in the field of biocontrol of postharvest fungal rot in apples(PHFRA)over the past two decades.It...Our study consists of a careful literature review carried out with the aim of better understanding the models developed in the field of biocontrol of postharvest fungal rot in apples(PHFRA)over the past two decades.It aims,more specifically,to shed light on the progress made by examining the products developed,their nature,their target pathogens,their effectiveness,theirs modes of action and the stage of their development.The post-harvest biocontrol of apples has made remarkable progress during the last twenty years of research.Several products(yeasts,bacteria,filamentous fungi and actinomycetes)have been selected.Some,are already marketed,others are at different stages of development.However,several points limit the optimal use of microbial antagonists in the bio-management of post-harvest apple rots as an alternative to chemicals.It is,in fact,still necessary to develop appropriate formulations of these microbial biocontrol agents,to better study their mechanisms of action,to test them under commercial conditions and against a broad spectrum of pathogens and hosts.However,although sometimes considered less effective than chemical treatments,biocontrol products based on microorganisms have major advantages for an application in an integrated post-harvest apple protection strategy.展开更多
基金The work was supported by the Fundamental Research Funds of the Central University,China(Grant Number 2572017AA03 and Grant Number 2572014BA15).
文摘A transcriptomic database was constructed to study the biocontrol mechanisms of Trichoderma harzianum ACCC30371 using high quality UniGenes following growth in eight culture media[(1/2PD,minimal medium MM(containing dextrose 10 g L^-1),C starvation medium(derived from MM without dextrose),N starvation medium(derived from MM without ammonium sulphate),and four kinds of phytopathogenic fungi cell wall media].A 4 Gbp transcriptome was generated and 96.7%of the database had a sequencing error rate less than 1%.A total of 25,013 UniGene sequences were obtained with a mean length of 1135 nt.There were 2571 sequences longer than 3000 nt.The National Center for Biotechnology Information Accession number of this transcriptome is SRR8382572.There were 16,360 Unigenes annotated to the Nr protein database,9875 to the SwissProt database,10,266 to the KEGG database,7164 to the COG database,and 1508 to the GO database along with their protein functional annotations.There were 16,723 functional genes identified.We identified 402 bio-control genes,including 14 related to competition,311 to mycoparasitism,76 to antibiosis,and one related to eliciting a plant response.This shows that T.harzianum ACCC30371 has integrated biocontrol mechanisms,and of these mechanisms,mycoparasitism is the most prevalent.Antibiosis and induced systemic resistance also play important roles.These results provide a foundation for further research into the biocontrol mechanisms of Trichoderma,as well as the development and utilization of biological fungicides.
文摘Biocontrol by Trichoderma has been studied mainly with selected isolates of T. harzianum, T. atroviride and T. asperellum, which are members of sections Pachybasium and Trichoderma. In contrast, species from section Longibrachiatum have only rarely been studied. On the other hand, one taxon from this section-Hypocrea jecorina (anamorph: Trichoderma reesei)-has been widely used for the production of cellulolytic and hemicellulolytic enzymes and recombinant proteins. As far as Trichoderma is concerned, molecular genetic methods and tools are most advanced in H. jecorina, and its genome has recently been fully sequenced, thus making this taxon a model organism for the genus. Here we will demonstrate that H. jecorina is able to antagonize plant pathogenic fungi in plate confrontation tests, and can protect tomato and cucumber plants against Pythium ultimum blight. Using this as a model case, we made use of available H. jecorina mutants to investigate (a) whether carbon catabolite repression via the Cre1-regulator protein has an impact on biocontrol, and (b) whether cellulase gene expression is necessary for biocontrol of P. ultimum. In the first case, plate confrontation tests and in planta experiments yielded opposite results, i.e. while a Cre1 mutant was more active in antagonization of fungi on plates, the survival rates of P. ultimum-inoculated cucumber plants was lower than with the H. jecorina wild-type strain. Mutants of H. jecorina, unable to form cellulases, were still able to antagonize fungi on plates and provided similar protection of tomatos against P. ultimum as the wild type, indicating that the pronounced biocontrol ability of H. jecorina against fungi with cellulose-containing cell-walls is not due to its high cellulolytic activity. A strain disrupted in the light-modulator gene envoy (Schmoll et al., ms submitted) exhibited in planta biocontrol activity strongly exceeding that of the wild-type strain, thereby providing a first link between Trichoderma biocontrol and light. In view of the numerous other metabolic and regulatory mutants of H. jecorina available, we suggest that this fungus should increasingly be used in basic studies on the biochemistry and genetics of biocontrol.
基金supported by the Australian Research Council International Linkage Fellowship(No.LX0560210)the National Natural Science Foundation of China(No.30600082).
文摘Biocontrol agents are safe and environmental friendly alternatives for pesticides in agriculture application. Trichoderma viride WEBL0703 performed a high level of antagonistic activity toward a broad spectrum of phytopathogens and was determined as a biocontrol agent, which was produced by solid state fermentation using grape marc and wine lees. The maximum yield of T. viride conidia was up to 6.65 × 10^9 CFU/g initial dry substrate (IDS) after 10 d fermentation. As important enzymes for protecting plants from disease, chitinase, β-glucanase, and pectinase yields were 47.8 U/g IDS, 8.32 U/g IDS and 9.83 U/g IDS, respectively. These results show that it is feasible to convert winery wastes to a value-added and environmental friendly biocontrol agent.
基金financially supported by the National Basic Research Program of China (2013CB127501)the National Key Research and Development Program of China (2016YFD0201003)the National Natural Science Foundation of China (31272021, 31571987)
文摘Streptomyces rubrogriseus HDZ-9-47,isolated from eggs of Meloidogyne spp.,was evaluated as a potential biocontrol agent of Meloidogyne incognita under in vitro and protective field.Microscopic observations showed that HDZ-9-47 parasitized eggs of M.incognita within 7 days.In vitro,the culture filtrate of HDZ-9-47 caused 97.0%mortality of second-stage juveniles(J2s)of M.incognita and inhibited more than 50%egg hatching.In the field,compared with the control,the rootknot index and J2s density in the treatment of drench the broth contained 1012 HDZ-9-47 spores were respectively reduced by 51.1 and 80.7%at 90 days post transplantation,which were better than that in other application doses and methods.In addition,reduction rates of root-knot index and J2s density of the treatment of combined application of HDZ-9-47 with biofumigation was 87.1 and 91.0%,respectively,better than either of HDZ-9-47 or biofumigation used alone or fosthiazate treatment.And tomato yield also increased by 16.1%.Together,our results suggest that HDZ-9-47 could be an effective biocontrol agent of M.incognita,and that application of HDZ-9-47 combined with cabbage residue biofumigation was a promising and sustainable option for M.incognita control.
文摘Several bacterial strains were isolated from different rhizospheres. Among these, strain PDY7 exhibited strong antibacterial activity against the rice bacterial blight (BB) pathogen Xanthomonas oryzae pv. oryzae (Xoo) by the laboratory dual plate assays. The antibacterial property of the strain PDY7 was further investigated for the production of 2,4-diacetylphloroglucinol (DAPG), which amplified a characteristic of 629-bp DNA fragment by PCR-based screening method using phlD primers. The application of phlD positive strains was carefully evaluated for disease control and growth promotion of rice plants under field conditions. The selected strain PDY7 suppressed the rice BB by 58.83% and 51.88% under glass house and field conditions, respectively. In addition, the strain PDY7 showed significant two-fold increase in root length (18.08 cm), shoot length (29.81 cm), and grain yield (96.07 g). Strain PDY7 promoted the growth of rice plants by production of indole-3-acetic acid (IAA), which was determined by high performance liquid chromatography (HPLC) analysis. Our findings suggest that PDY7 belongs to the P. fluorescens group and can serve as potential biocontrol of BB as well as biofertilizer agent for growth promotion of rice.
文摘Modern agribusiness plays a vital role in safeguarding and improving the production,quality,and quantity of food,feed,fiber,and fuel.Growing concerns over the impact of chemical pesticides on health and the environment have stimulated the industry to search for alternative and greener solutions.Over the last years,the RNA interference(RNAi)process has been identified as a very promising new approach to complement the arsenal of foliar spray,soil,or seed treatments applied as chemical and biological pest control agents,and of plant-incorporated protectants(PIPs).RNA-based active ingredients(AIs)possess a unique mode of action and can be implemented via both genetic modification(GM)and biocontrol approaches.RNA-based AIs promise to deliver the selectivity and sustainability desired in future crop protection agents.This is due to their utilization of a natural process to exert control and their high level of selectivity,which leads to reduced risk for non-target organisms(NTOs).This review discusses the advantages and limitations of RNA-based solutions in crop protection and recent research progress toward RNA-based biocontrols against the Colorado potato beetle(CPB),corn rootworm(CRW),and soy stink bug(SSB).Many challenges still exist on the road to the implementation of a broad range of RNA-based products and their widespread use and application.Despite these challenges,it can be expected that RNA-based AIs will become valuable new tools complementing the current arsenal of crop-protection solutions.
基金supported by the National Natural Science Foundation of China (31301731, 31428020)the National Science and Technology Major Project (2014ZX08009013B)
文摘Bacillus thuringiensis Bt185 and its insecticidal spectrum-expanded engineering strains are considered as potential biocontrol agents to soil insect Holotrichia parallela,Holotrichia oblita or Anomala corpulenta.Here we reported the complete genome of strain Bt185,it harbors eight plasmids,and plasmid p BT1850294 carries three cry8 genes.
文摘Methicillin-resistant Staphylococcus aureus (MRSA) is among the most alarming pathogens affecting both humans and the global bovine industry. The current control measures in hospitals and on farms for MRSA have proven to be inadequate leaving a need for new rapid control methods to curb MRSA infections in situ. New control measures for bacterial infection are widely sought, with particular interest in the applications for bacteriophages (phages) as a biocontrol or therapeutic agent. The current study uses a wild highly lytic phage isolated from cow’s milk taken from three farms in Baghdad, Iraq. The resulting phage was able to rescue 100% of the mice from a median lethal dose (LD50) or (1 × 108 CFU mL-1 per mouse) for MRSA wild isolates achieved when the phage: bacteria ratio was 100:1. Even when treatment was delayed for 6 h post lethal infection, to the point where all mice were moribund, 80% of them were rescued by a single injection of this phage preparation. Based on the current results, a comprehensive study is needed to guide further research on the MRSA phage as a biocontrol for MRSA mastitis in dairy cows to replace or reduce the use of antibiotics in animal husbandry.
基金Supported by Chinese National Programs for High Technology Research and Development(2003AA241140)
文摘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 mechanism for plant diseases and application of Trichoderma spp., especially Trichoderma harzianum in recent years
基金supported by the National High Technology Research and Development Program(13th Five-Year Plan Program,Grant Number 2016YFC0501505)the Fundamental Research Funds of the Central University,China(Grant Number 2572017CA06)。
文摘This study investigates the biocontrol potential of Trichoderma asperellum mutants against Rhizoctonia solani, Alternaria alternata, and Fusarium oxysporum and growth promotion of Populus davidiana 9 P. alba var.pyramidalis(Pd Pap poplar) seedlings. A T-DNA insertion mutant library of T. asperellum was constructed using Agrobacterium tumefaciens-mediated transformation.Sixty-five positive transformants(T1–T65) were obtained.Growth rates of the mutants T39 and T45 were the same,39.68% faster than the WT. In toxin tolerance tests, only T39 had greater tolerance to A. alternata fermentation broth than the WT, but mutant T45 had the same tolerance as the WT to all fermentation broths. Furthermore, T39 and T45 had a greater antagonistic ability than the WT strain against R. solani and A. alternata. The inhibition rate of the mutants T39 and T45 against A. alternata are 73.92% and80.76%, respectively, and 63.51% and 63.74%, respectively. Furthermore, the three strains increased the activities of superoxide dismutases, peroxidase, catalase(CAT)and phenylalanine ammonia lyase(PAL) in Pd Pap seedling leaves. CAT and PAL activity in the Pd Pap seedling leaveswas 11.25 and 5.50 times higher, respectively, in the presence of T39 than in the control group and 12 and 6.35 times higher, respectively, in the presence of T45 than in the control group. All three strains promoted seedling growth and the root and stem development, especially mutant T45. Mutants T39 and T45 reduced the incidence of pathogenic fungi in poplar and stimulated poplar seedling growth.
文摘The“oil stain disease”has become a phytosanitary status that involves economic losses for farmers who produce gulupa(Passiflora edulis Sims).For this reason,this research aimed to evaluate the biocontrol activity of Bacillus subtilis ATCC 55033 in a culture medium based on fermented millet as a biocontrol product of the disease.Initially,metabolite production of seven strains of B.subtilis and a reference strain B.s(ATCC 55033)was evaluated;in addition,the in vitro antagonistic ability was evaluated against Xanthomonas axonopodis.Two experiments were performed under in vitro conditions:(1)study of the presence of halos of hemolysis due to metabolite production;(2)analysis of the antagonistic ability by using double layer.It was observed that concerning the average,a number five times bigger of halos of hemolysis and 10 times bigger halos of inhibition in vitro on the growth of X.axonopodis in the strains B.s(ATCC 55033)and B.s TB2 over other strains.Subsequently,the evaluation was performed under greenhouse conditions,based on a randomized block design,in which two treatments were applied over the soil:(1)application of the fermented medium based on millet with B.s ATCC 55033,24 h before X.a inoculation;(2)application of 5 d post-inoculation.It was observed that the treatment,previous infective process,obtained an average percentage of severity equal to 42.044%.In addition,after the evaluation month,a foliage restoration was presented.In conclusion,it is suggested that these products could act as inducers in the plant systemic resistance to trigger defense responses to infection of X.a.
文摘Fungi and bacteria as insecticides have been tested to control forest pests for more than ten years, they are the saine kind of biocontrol agent with the different conentrations. thesame kind of the biocontrol agent with the different origin areas, and the mixtures of the different kinds of biocontrol agents. The infection mechanism of virus was discussed. moreover. the mfluence of these biocontrol agents on the small animals was also evaluated.
文摘The increasingly strict regulation of the use of phytosanitary products and the will of the populations to move towards sustainable development allow bio-sourced products and more particularly for biocontrol in the field of pesticides to progress. The study carried out here concerns the evaluation of the potency of Bacillus amyloliquefaciens Bc2 and Trichoderma harzianum to fight against strawberry cultures infected with anthracnose (Fragaria × ananassa Duch.). The studies were carried out in the laboratory and in the field. The results indicate that B. amyloliquefaciens Bc2 and Trichoderma harzianum TR are effective for the biological control of anthracnose, gray mold and powdery mildew on strawberries grown in field conditions. The increase in plant size and the number of fruits produced with these control agents has also been observed.
基金supported by the National Science Fund for Distinguished Young Scholars of China(30225030)the National Natural Science Foundation of China(30170663).
文摘Two antagonistic yeasts, Thichosporon pullulans and Cryptococcus laurentii, were investigated for their biocontrol potential to blue mold rot and rhizopus rot on harvested peach fruits(Prunus persica L. Batsch, cv. Okubao), alone or in combination with a low dose of iprodione(50 μg ml-1). The results indicated that T. pullulans and C. laurentii were effective at reducing disease incidence and severity of blue mold rot and rhizopus rot in peach fruits. Biocontrol efficacy of C. laurentii and T. pullulans were significantly enhanced by combination with a low dose of iprodione(50 μg ml-1)against blue mold and rhizopus rot in peach fruits. T. pullulans and C. laurentii combined with a low dose of iprodione(50 μg ml-1)resulted in better disease control than either iprodione or the yeasts used alone. Dipping fruits in suspensions of antagonist cells showed the similar control effect as the treatment with iprodione(500μg ml-1).
文摘This study was to evaluate the ecological risk of strain E26 (Agrobacterium sp.) by detecting its survival in waters and its effects on rhizosphere microorganisms. The data showed that E26 could not be detected in distilled water, tap water, river water, and rainwater after 36, 36, 8, and 9 days, respectively. E26 did not reveal significant effects on the population of bacteria, fungi, and actinomyces in rhizosphere soil and on the root surface of grapevines.
基金Supported by National Natural Science Foundation of China(31400129&31770029)
文摘Bipolaris sorokiniana is an important disease causing wheat root rot. Different biocontrol strains were screened with the pathogen as the target. A total of 210 strains of bacteria and fungi preserved in the laboratory were preliminarily and secondarily screened by plate confrontation culture. The 17 strains of bacteria and 36 strains of fungi with good bicontrol effect were screened. Eventually, the best fungal strain and the best bacterial strain were obtained. The ITS fragments of fungi were amplified by PCR, and the target band of 571 bp was obtained. The 16 S gene frag-ments of bacteria were amplified by PCR, and the target band of 1 455 bp was obtained. Through morphological observation, the screened strains were identified. Finally, the bicontrol fungus was confirmed as Trichoderma asperellum and the bacterium was Bacillus amylofaciens.
文摘The present study evaluates the possible modes of action of antagonistic bacteria and their tolerance to UV radiation, temperature and osmotic stress. The partial 16S-23S rRNA gene sequencing of eight antagonistic bacteria had a high match with three bacterial genera: <em>Curtobacterium</em>, <em>Pantoea</em> and <em>Bacillus</em>. In this study, the three <em>Bacillus</em> isolates showed the most relevant production of enzymes, volatile organic compounds and antibiosis against <em>Exserohilum turcicum</em>. Respect to UV radiation and temperature <em>Pantoea</em> and <em>Bacillus</em> isolates were more tolerant;whereas the eight isolates were tolerant to osmotic stress in varying degree. The three <em>Bacillus</em> isolates have the greatest potential as biocontrol agents for foliar diseases in maize. The antagonistic action could be explained through different modes of action such as enzymes, volatile organic compounds and/or direct antibiosis by other secondary metabolites. <em>Bacillus</em> isolates tolerance to environmental stresses including UV radiation, temperature and osmotic stress is relevant for survival and persistence on the leaf surface. This work provides new information about the mode of action of antagonistic bacteria with proven efficacy against maize leaf pathogens. In addition, it provides information about the tolerance of antagonistic bacteria against different stress conditions. The data of the present study could contribute to the development of a successful foliar biofungicide.
基金Science and Technology Project of China Tobacco Guizhou Provincial Corporation(201918)Science and Technology Foundation of General Administration of Quality Supervision,Inspection and Quarantine of the People's Republic of China(2017IK257,2017IK261,2016IK075,2014IK022)+3 种基金Science and Technology Foundation of Guizhou Province(J[2013]2149)Humanities and Social Science Research Project of Guizhou Education Department(2022ZC016)Theoretical Innovation Project of Guizhou Province(Joint Project)(GZLCLH-2021-169)Construction of Guizhou Academic Pioneer.
文摘[Objectives]The paper was to study the toxicity of 9 biocontrol microbial products to adult population of Lasioderrma serricorne.[Methods]Nine biocontrol microbes were used as test materials to study their toxicity to the experimental population of L.serricorne adults.[Results]The toxicities of these biocontrol microbes from low to high at 5 d post spraying were:Luhai Beauveria bassiana powder(LC_(50)=462.752×10^(8) spores/L),Meichongzhi B.bassiana powder(LC_(50)=9713.157×10^(8) spores/L),Yiqiang Bio B.bassiana powder(LC_(50)=11203.321×10^(8)spores/L),Nongbao Bio B.bassiana powder(LC_(50)=12188.866×10^(8) spores/L),Yeshengwang B.bassiana powder(LC_(50)=21685.532×10^(8) spores/L);Fatu Bacillus thuringiensis suspension(LC_(50)=1.0844×10^(8) IU/L),Laojite B.thuringiensis suspension(LC_(50)=2.056×10^(8) IU/L),Lujinwa B.thuringiensis powder(LC_(50)=2.273×10^(8) IU/L),Nongbao Bio B.thuringiensis powder(LC_(50)=18.399×10^(8) spores/L).The toxicities of these biocontrol microbes from low to high at 10 d post spraying were:Nongbao Bio B.bassiana powder(LC_(50)=0.072×10^(8) spores/L),Yiqiang Bio B.bassiana powder(LC_(50)=2.484×10^(8) spores/L),Luhai B.bassiana powder(LC_(50)=44.551×10^(8) spores/L),Meichongzhi B.bassiana powder(LC_(50)=96.447×10^(8) spores/L),Yeshengwang B.bassiana powder(LC_(50)=723.347×10^(8) spores/L);Lujinwa B.thuringiensis powder(LC_(50)=0.0001×10^(8) IU/L),Fatu B.thuringiensis suspension(LC_(50)=0.045×10^(8) IU/L),Laojite B.thuringiensis suspension(LC_(50)=0.0644×10^(8) IU/L),Nongbao Bio B.thuringiensis powder(LC_(50)=1.899×10^(8) spores/L).The toxicities of these biocontrol microbes from low to high at 15 d post spraying were:Meichongzhi B.bassiana powder(LC_(50)=0.001×10^(8) spores/L),Nongbao Bio B.bassiana powder(LC_(50)=0.01×10^(8) spores/L),Yiqiang Bio B.bassiana powder(LC_(50)=0.084×10^(8) spores/L),Luhai B.bassiana powder(LC_(50)=2.370×10^(8) spores/L),Yeshengwang B.bassiana powder(LC_(50)=8.915×10^(8)spores/L);Lujinwa B.thuringiensis powder(LC_(50)=0.16×10^(4) IU/L),Laojite B.thuringiensis suspension(LC_(50)=0.185×10^(4) IU/L),Fatu B.thuringiensis suspension(LC_(50)=32.211×10^(4) IU/L),Nongbao Bio B.thuringiensis powder(LC_(50)=1590×10^(4) spores/L).[Conclusions]According to the three stages of tube rubbing,it is found that the control effects of Lujinwa B.thuringiensis powder and Meichongzhi B.bassiana powder are the best,and the results will provide technical support for the biological control of L.serricorne adults.
文摘The quantity of bio-laboratories and bio-factories in Uzbekistan increases every year.In 1970,there were only 4,in 1971,16,in 1985,710,in 1990,774,and in 2000,790.At present there
文摘Our study consists of a careful literature review carried out with the aim of better understanding the models developed in the field of biocontrol of postharvest fungal rot in apples(PHFRA)over the past two decades.It aims,more specifically,to shed light on the progress made by examining the products developed,their nature,their target pathogens,their effectiveness,theirs modes of action and the stage of their development.The post-harvest biocontrol of apples has made remarkable progress during the last twenty years of research.Several products(yeasts,bacteria,filamentous fungi and actinomycetes)have been selected.Some,are already marketed,others are at different stages of development.However,several points limit the optimal use of microbial antagonists in the bio-management of post-harvest apple rots as an alternative to chemicals.It is,in fact,still necessary to develop appropriate formulations of these microbial biocontrol agents,to better study their mechanisms of action,to test them under commercial conditions and against a broad spectrum of pathogens and hosts.However,although sometimes considered less effective than chemical treatments,biocontrol products based on microorganisms have major advantages for an application in an integrated post-harvest apple protection strategy.