首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 546 毫秒
1.
利用拮抗微生物不仅能有效防治植物病原细菌,而且对环境友好。该研究中,拮抗菌株XZQ-20分离自健康杨树根际土壤,基于形态学特征、生理生化特性和16S rDNA序列分析将该菌株鉴定为深层类芽孢杆菌(Paenibacillus profundus),XZQ-20具有蛋白酶活性,其对4种植物病原细菌欧美杨细菌性溃疡病菌(Lonsdalea quercina)、丁香假单胞菌(Pseudomonas syringae)、软腐欧文氏菌(Erwinia carotovora)和核桃黄极毛杆菌(Xanthomonas juglandis)均具有较强的拮抗活性,抑菌圈大小分别为(11.75±1.06)mm、(13.3±2.26)mm、(16.75±0.07)mm和(7.55±1.06)mm。此外,对拮抗菌株XZQ-20的无菌培养滤液的拮抗活性进行测定,发现其无菌培养滤液也表现出了较强的拮抗活性,对4种植物病原细菌的抑菌圈直径分别达到(8.18±0.75)mm、(7.63±0.88)mm、(8.03±0.93)mm和(8.60±0.53)mm。研究结果表明拮抗菌株XZQ-20可用作为潜在的高效防治植物病原细菌的生防制剂。  相似文献   

2.
拮抗菌株SY-15是从杨树根际土壤中分离获得的一株能高效拮抗金黄壳囊孢菌Cytospora.chrysosperma的拮抗细菌.研究基于形态学特征、生理生化特性和16S rDNA序列分析鉴定了菌株SY-15的分类地位,并分别采用带药平板法和二分皿法分析了其抑菌活性,为进一步开发利用拮抗菌株SY-15提供科学依据.结果 表明:拮抗菌株SY-15最终鉴定为枯草芽孢杆菌Bacillus subtilis,其无菌培养滤液和挥发性气体均能有效抑制金黄壳囊孢菌、迂回壳囊孢菌C.ambiens和黑腐皮壳菌C.mali的生长,处理60 h后,无菌培养滤液对3种植物病原真菌的抑菌率分别达到88.89%、60.39%和53.02%.处理36 h后,挥发性气体对3种植物病原真菌的抑菌率分别达到100%、76.98%和63.41%.此外,还发现拮抗菌株SY-15能产生蛋白酶和纤维素酶.研究表明拮抗菌株SY-15是一株潜在的高效防治杨树腐烂病及其他植物真菌病害的菌株资源.  相似文献   

3.
一株桑椹菌核病生防菌分离鉴定及其拮抗作用分析   总被引:1,自引:0,他引:1  
桑椹菌核病是主要由桑实杯盘菌Ciboria shiraiana、桑椹核地杖菌Scleromitrula shiraiana和肉阜状杯盘菌Ciboria carunculoides引起的果桑毁灭性病害。采用组织分离法从健康桑椹中分离纯化获得内生细菌Wh-1,对其进行抑菌谱测定和种类鉴定;以桑实杯盘菌为靶标菌株研究Wh-1发酵滤液拮抗活性,分析拮抗机理。结果表明:Wh-1对分离自发病桑椹上的真菌具有显著拮抗作用,对桑椹核地杖菌,肉阜状杯盘菌,桑实杯盘菌的抑菌率分别为100%,100%,63.15%;基于形态学、Biolog鉴定及16S rDNA序列分析结果,将该菌株鉴定为贝莱斯芽孢杆菌Bacillus velezens,其在PDB中振荡培养48 h,发酵滤液具有较强拮抗活性;PDA平板中发酵滤液的体积分数为5%时可完全抑制菌丝的生长;且发酵滤液热稳定性好。发酵滤液对桑实杯盘菌菌丝有致畸作用,Wh-1菌株具有脂肽基因(srfAA)、芽孢菌霉素基因(bmyB)、杆菌溶素基因(bacA)、丰原素基因(fenD)和生物素基因(bioA)脂肽类化合物合成相关功能基因。菌株Wh-1可作为开发桑椹菌核病生防制剂较为理想的候选菌株。  相似文献   

4.
采用梯度稀释涂板法和平板对峙培养法从油茶林根际土中分离、筛选到了一株对油茶炭疽病原具有拮抗作用的细菌,编号为YCSF-1,其对油茶炭疽病病原的抑菌圈直径达20.6 mm。经过形态学、生理生化测定、16Sr RNA序列比对鉴定,该菌株为侧孢短芽孢杆菌(Brevibacillus laterosporus)。该研究为油茶炭疽的生物防治提供菌株。  相似文献   

5.
在土壤有益微生物的分离、筛选中获得一株拮抗细菌Bs-03,抑菌谱测定结果表明该菌对供试的多种植物病原真菌具有较强的抑菌活性,表现较为广谱的抑菌活性。通过对菌株的培养性状、形态特征、生理生化特性等试验项目,初步鉴定为枯草芽孢杆菌(Bacillus subtilis)。采用平板对峙培养法测定Bs-03菌株抑菌活性,结果表明Bs-03对供试的14种植物病原真菌,除花生白绢病菌外,都具有抑菌活性。其中对核桃炭疽病菌、苹果轮纹病菌、黄瓜灰霉病菌、冬枣黑斑病菌效果最好,与其他处理在P0.05水平上具有显著性差异。该菌具有较好的开发应用前景。  相似文献   

6.
采用平板稀释法在几种中药材中分离内生拮抗细菌,结果人参根中分离到的内生拮抗细菌菌株数较多。采用平板对峙法筛选高效拮抗菌菌株,其中菌株BJ33对人参黑斑病具有很强的抑菌活性,其抑制率达到了80%。根据BJ33菌株的形态和生理生化特征以及采用16S rDNA同源性分析方法鉴定为解淀粉芽孢杆菌Bacillus amyloliquefaciens。BJ33菌株及发酵浓缩液对供试的6种植物病原菌菌丝生长均具有较强的抑制作用;BJ33菌株发酵浓缩液在15~35℃和pH5~11均具有较强的抑菌活性;BJ33菌株发酵浓缩液对高温、紫外线以及蛋白酶等具有较强的稳定性。  相似文献   

7.
油茶根际硅酸盐细菌拮抗菌筛选及稳定性分析   总被引:2,自引:0,他引:2  
油茶Camellia oleifera是我国重要的木本油料树种,其种子提取的茶油富含不饱和脂肪酸,素有"东方橄榄油"之称。由层生镰刀菌Fusarium proliferatum引起的油茶根腐病,导致植株不能正常吸收养分和水分导致干枯死亡,给油茶产业发展带来了严重的威胁。硅酸盐细菌是一类重要的微生物肥料菌种,同时具有一定的生防功效。从油茶根际土壤中分离、纯化获得硅酸盐细菌,采用平板对峙培养法,筛选对油茶根腐病原菌层生镰刀菌有拮抗作用的菌株。结果表明:分离纯化得到的73株硅酸盐细菌,有7株具有具有拮抗作用,其中菌株K56抑制效果最好,平板对峙抑制率达到85.9%;对其稳定性进行分析发现,该菌抑菌活性物质经过热处理以后,基本失去生物活性;在pH值5.0~8.0时都有一定的抑菌活性,其中pH值6.0抑菌效果最好,抑菌圈直径达到8.8 mm;紫外线照射60 min后,抑菌圈直径为8.6 mm。抗菌谱测定结果表明,该菌的生防效果较专性。  相似文献   

8.
树木褐根病是由有害木层孔菌 (Phellinus noxius) 引起的一类土壤传染性根部病害,为了实施对 这类病害的生物防治,结合唯一氮源 1- 氨基环丙烷 -1- 羧酸(ACC)为底物和平板对峙法,从澳门松山市 政公园健康树木的根际分离得到 1 株对有害木层孔菌具有较强拮抗活性的菌株 1583。采用一对细菌通用 引物 PCR 扩增获得菌株 1583 的 16S rDNA 基因序列,其片段大小为 1 496 bp,系统进化树显示菌株 1583 与 Burkholderia seminalis 的亲缘关系最近,综合结果鉴定该菌株为伯克霍尔德菌(Burkholderia sp.)。拮抗 性研究表明,菌株 1583 对油菜菌核病病原菌(Sclerotinia sclerotiorum)、黑松叶斑病病原菌(Pestalotiopsis sp.)、香蕉枯萎病病原菌(Fusarium oxysporum f. sp. cubense)、白蝴蝶炭疽病病原菌(Colletotrichum sp.) 和美人蕉瘟病病原菌(Pyricularia cannaecola hashioka)等植物病原真菌均有明显的抑制作用。  相似文献   

9.
[目的]为获得高效拮抗3种兰花病原真菌胶孢炭疽菌、尖孢镰孢菌和腐皮镰孢菌的菌株。[方法]使用平板对峙法筛选拮抗菌株,结合形态特征观察、生理生化试验和16S rRNA基因序列分析的方法对目的菌株进行鉴定。[结果]筛选获得5株同时拮抗三种病原菌的菌株,其中菌株GT312拮抗效果明显。16S rRNA基因序列分析显示,该菌株与Bacillus amyloliquefaciens(模式菌株FZB42T)相似性最高,为99.93%。菌株形态特征观察、生理生化试验结果与B.amyloliquefaciens描述一致。[结论]菌株GT312可同时拮抗3种兰花病原真菌,鉴定为解淀粉芽孢杆菌,为兰花病害的生物防治提供了菌株资源。  相似文献   

10.
毛竹枯梢病拮抗细菌分离鉴定及其拮抗物质   总被引:2,自引:0,他引:2  
从采集的土样中筛选到对毛竹枯梢病致病菌竹喙球菌具有拮抗作用的菌株78株,通过复筛选出1株拮抗活性较高的拮抗菌株6-59.通过形态观察、生理生化试验及16S rDNA的序列分析鉴定该菌株为巨大芽孢杆菌.经有机溶剂萃取和盐析法初步推断该菌株的拮抗物质为蛋白类物质.通过单因素试验和正交试验对菌株6.59摇瓶发酵条件进行优化,最终确定其最佳发酵条件为:蔗糖2%、蛋白胨3%、MgS04·7H2O 0.03%、KCl 0.02%、种龄18 h、培养基初始pH 7.0,250 mL三角瓶装液量50 mL、接种量4%、发酵时间72 h.在此条件下培养得到的菌株6-59的发酵液,其抑菌圈直径可达25.8 mm.  相似文献   

11.
Endohyphal organisms of endophytic fungi can induce, or promote, beneficial effects of their respective host fungi to the host plant that harbours them. The Cupressaceae plant family (Coniferales) hosts highly bioactive endophytic fungi. Here, we show that a fraction of such endophytic fungi harbours bioactive endohyphal bacteria with a non‐obligatory symbiotic lifestyle. Indeed, 5 of 16 (31.25%) endophytic fungi of Cupressus sempervirens harboured endofungal bacterial strains of Bacillaceae (G+, Bacilli) and Sphingomonadaceae (G?, α‐Proteobacteria), that is Bacillus pumilus (from the fungi Leptosphaeria CSE211 and Pyrenochaeta CSE134), Bacillus subtilis (from the fungi Leptosphaeria CSE212 and Ascorhizoctonia CSE148) and Sphingomonas paucimobilis (from the fungus Ascorhizoctonia CSE195). Notably, each endophytic fungal species contained only one endofungal bacterial species that was stably maintained in symbiosis over several rounds of subculturing. Moreover, we investigated whether cypress endofungal bacteria (CEB) could benefit their host fungus competing with other fungi and bacteria or the host plant against the invading microorganisms. In vitro assays indicated that CEB possessed antagonistic activity against cypress endophytic and pathogenic microbiome. Also, CEB metabolites and volatile compounds (VOCs) exhibited antifungal and antibacterial activity against the target microbiome. Bioactivity of CEB was less than that of the endophytic microbiome of Cupressaceae, on which we reported earlier. In conclusion, our work is the first to document endohyphal bacteria of fungal endophytes of C. sempervirens and the bioactivity of such endohyphal symbionts. These findings implicate a complicated interrelationship among host plant, endophytic microbiome and endofungal bacteria, which might be of high importance for evolutionary, as well as environmental and agricultural studies. Eventually, endohyphal bacteria may be introduced as a novel source for lead molecule discovery.  相似文献   

12.
Antibacterial screening of plants used in Iranian folkloric medicine   总被引:6,自引:0,他引:6  
Bonjar GH 《Fitoterapia》2004,75(2):231-235
Fifty methanolic plant extracts belonging to 44 plant species of 33 families finding use in Iranian folkloric medicine were screened for antibacterial activity. Thirty samples, including 28 species in 20 families, had antibacterial activity against at least on one of the bacteria. Among the active plants, 32.6% were active against G(-), 62% against G(+), and 47.3% against both G(-) and G(+) bacteria. Dianthus coryophyllus was active against all tested G(-) and G(+) bacteria except Micrococcus luteus. Most susceptible G(-) bacteria were Klebsiella pneumoniae and Bordetella bronchiseptica and least susceptible G(-) bacterium was Escherichia coli. In G(+) bacteria, most and least susceptible were Staphylococcus aureus and M. luteus, respectively. The least MIC, as 0.62 mg/ml, belonged to Myrtus communis seeds against S. aureus, Bacillus cereus and B. bronchiseptica, and to Terminalia chebula ripe seeds against S. aureus.  相似文献   

13.
Essential oils are by-products of plant metabolism that are now known to interfere with basic metabolic, physiological and behavioral functions of insects, thereby having promise for use as pest control agents. Accordingly, four essential oil compounds, thymol, 1,8-cineole, linalool and pulegone, were evaluated against the diamondback moth, Plutella xylostella (Linnaeus) (Lepidoptera: Yponomeutidae), to determine their acute toxicity. Thymol and 1,8-cineole were highly toxic to third instars with a LD50 of 0.22 and 0.41 μg/larva, respectively. Linalool and pulegone were moderately active against this insect species, exhibiting <45 % mortality in up to 15 μg/larva. However, in biorational mixtures pulegone was synergistic to both thymol and 1,8-cineole where the increase in activity was almost twofold. Thymol and 1,8-cineole, though active individually against P. xylostella larvae, were antagonistic as biorational mixtures. Linalool was antagonistic in all combinations. In various assays with detoxification enzymes in treated conditions, there was a significant increase in enzyme levels both in vivo and in vitro. Thymol and 1,8-cineole were the active toxicants against P. xylostella, with significant potential to control this pest as biorational mixtures in a synergistic combination with pulegone. Induction in enzyme levels by these compounds suggests possibilities of resistance, which at present remains a speculation, but cannot be summarily ignored because the induction of enzymes due to involvement of detoxification enzymes in the metabolism of a broad range of xenobiotics and secondary metabolites in plants is well known.  相似文献   

14.
【目的】杨树作为我国最重要的工业用材林树种之一,对其长期的生产力维护和人工林的健康管理是林业和生态建设的重中之重。近年来,杨树根腐病的防治措施作为林学界亟待解决的重要问题,目前以化学防治方法为主,但其存在许多环境危害,所以具有诸多优点的生物防治成为了现在国内外的研究焦点,找到生防菌是研究的重中之重。以一系列实验分离筛选到用于防治根腐病的低温适生菌为创新点,旨在找到对杨树根腐病菌具有拮抗作用的生防菌,并明确其分类地位,令其在杨树根腐病的生物防治生防菌种类方面作为参考,也为进一步研究其定殖特性、林间防效及生物安全性等问题提供前期基础。【方法】为了筛选出新的低温适生生防菌菌种资源,采用稀释涂布平板法从杨树土壤中分离得到20株芽孢杆菌,经过初步筛选得到了拮抗效果最好的一株芽孢杆菌B42,并对其进行分离纯化,采用平板对峙法对该芽孢杆菌的抑菌活性进行测定,然后鉴定明确其分类地位。【结果】该芽孢杆菌对杨树根腐病菌具有显著的拮抗作用,同时对茄病镰刀菌、红松根腐病镰刀菌、山核桃干腐病菌、链格孢、油茶炭疽病菌、白腐菌均具有广谱抗性。【结论】根据菌体的形态特征、生理生化指标以及16S rDNA序列分析的结果,鉴定该菌B42为贝莱斯芽孢杆菌Bacillus velezensis。  相似文献   

15.
冬枣浆胞病病原微生物的分离与鉴定   总被引:1,自引:0,他引:1  
对冬枣贮藏期浆胞病病原微生物进行了连续系统的分离和鉴定,试验结果表明:贮藏冬枣浆胞病病原真菌主要为两种,半知菌亚门交链孢霉属(Alternaria Nees Wallr.)和半知菌亚门无孢菌群根菌索菌(Rhizomorpha Roth.ex Fr.);连续3年均分离到的贮藏冬枣浆胞病病原细菌有4种,对4种病原细菌进行了基因组DNA的提取及rDNA片段的扩增,并完成了062281菌株rDNA片段的序列测定,经过同源性分析,将062281号菌株鉴定为枯草芽孢杆菌Bacillus subtilis。  相似文献   

16.
The β-carboline alkaloids of Peganum harmala L were extracted through a bioassay-guided fractionation and their antimicrobial activities were investigated. Results revealed significant differences (P > 0.05) between compounds depending on the microorganism tested and the application method. When examined individually, harmine was the most effective against Proteus vulgaris, Bacillus subtilis and Candida albicans where inhibition zones ranged between 21.2 and 24.7 mm. Potentiality of the alkaloids was increased when applied as binary mixtures suggesting a kind of synergistic interaction with inhibition zones reaching 31.5 mm with the total alkaloidal extract. We recommended the use of such compounds as new antimicrobial biorationals.  相似文献   

17.
In this study, a total of 68 endophytic bacteria were isolated from different tissues of walnut trees. About 55% and 22% of the strains had the ability to produce indole acetic acid and gibberellic acid, respectively. The capability of isolates to solubilize phosphate, growth on N‐free medium, siderophore, protease and lipase production was varied. Based on phenotypic grouping and plant growth promotion properties, twelve isolates were selected and 16S rRNA gene‐based phylogenetic analysis revealed that strains showed 99%–100% similarity to Pseudomonas, Bacillus, Arthrobacter, Roseomonas and Streptomyces genera. Amongst the selected strains, PS12, KS54, JS66 and KS74 showed root and shoot growth enhancement of poplar cutting. NS70, KS54 and PL36 strains showed antagonistic activity against Pseudomonas syringae pv. syringae;RR47, KS74 and NR69 strains had inhibition effects against Brenneria nigrifluens; and JS66 and RR26 strains had antagonistic activity against both phytopathogens under in vitro conditions. This is the first reported study to elucidate the endophytic bacterial diversity associated with walnut trees with beneficial attributes.  相似文献   

18.

Objectives

Jatropha tanjorensis was investigated scientifically to generate evidence for the efficacies reported in traditional systems and the results are given here.

Methods

Different concentrations of the solvent extracts of leaves and four isolated compounds were tested against human pathogenic microorganisms such as gram-positive bacteria of Bacillus cereus, Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermis, gram-negative bacteria of Aeromonas hydrophila, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus mirabilis, Proteus vulgaris, Salmonella paratyphi, Salmonella paratyphi A, Vibrio alcaligenes, Vibrio cholerae and fungi of Aspergillus fumigatus, Candida albicans, Microsporum gypseum and Trichophyton rubrum by agar-well diffusion and disk diffusion methods.

Results

In agar-well diffusion method, maximum activity was recorded in a concentration-dependent manner. The extracts recorded activity against bacteria such as 17–26, 15–25 and 13–24 mm to methanol extract and 15–24, 14–23 and 12–22 mm to chloroform extract at 50, 25 and 12.5 mg/ml respectively and fungi such as 9–15 mm to A. fumigatus and 5–16 mm to T. rubrum. Maximum activity was 30–46, 27–43 and 17–40 mm to friedelin and 23–46, 28–44 and 18–41 mm to R (+) 4-hydroxy-2-pyrrolidinone against bacteria and 12–37, 8–34 and 31–33 mm to friedelin and 12–40, 11–35 and 10–33 mm to R (+) 4-hydroxy-2-pyrrolidinone against fungi at 10, 5 and 2.5 mg respectively.

Conclusions

The present study concludes that friedelin, β-amyrin, stigmasterol and R (+) 4-hydroxy-2-pyrrolidinone present in the methanol extract could be responsible for the broad spectrum of antimicrobial activity and provide scientific evidence.  相似文献   

19.
杨树烂皮病菌颉颃菌株的初步筛选与分子鉴定   总被引:1,自引:0,他引:1  
对杨树烂皮病菌的平板对峙试验结果表明,6种颉颃真菌中木霉的抑菌率最高为51%,而颉颃细菌4个菌株的抑菌率均在60%左右,说明颉颃细菌的抑菌效果明显高于颉颃真菌;对B137等4株颉颃细菌的分子鉴定认为,1株为枯草芽孢杆菌(Bacillus subtilis),2株为解淀粉芽孢杆菌(Bacillus amyloliquefaciens),还有1株为苏云金杆菌(Bacillus thuringiensis,Bt);解淀粉芽孢杆菌和苏云金杆菌对杨树烂皮病菌有较好的颉颃效果。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号