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1.
峨眉山珙桐根际和非根际土壤微生物的初步研究   总被引:1,自引:0,他引:1  
以四川峨眉山珙桐林为研究对象,选取珙桐林珙桐根际和非根际两种土壤样品,分别进行微生物的分离、测数,并根据菌株形态、培养特征和生理生化特性等,对根际和非根际土壤中的细菌、放线菌和真菌进行了初步鉴定.结果表明:从珙桐根际和非根际土壤中共得到细菌菌株85株,分属于9个属;放线菌菌株28株,分属于2个属;真菌菌株13株,分属于5个属.同一地区珙桐根际和非根际土壤中,珙桐根际土壤中的微生物的总数以及细菌、放线菌和真菌数量均低于非根际土壤.  相似文献   

2.
研究了凉州熏醋传统酿造大曲中细菌区系,对大曲中的细菌总数、醋酸菌、乳酸菌及耐热菌进行计数、分离纯化和鉴定,通过显微镜镜检、革兰氏染色、接触酶反应、需氧型、产酸产气、发酵性等特性测定,对分离的菌株进行了具体菌属鉴定.结果表明,大曲表面与大曲中心细菌区系差异明显;大曲中共分离到5株醋酸菌、8株乳酸菌和4株耐热菌;醋酸菌分属为醋杆菌属和葡糖杆菌属;乳酸菌分属为糖球菌属、链球菌属、魏斯氏菌属、乳球菌属和索丝菌属;耐热菌分属为微球菌属和芽孢杆菌属.  相似文献   

3.
基于高通量测序的连作百合土壤细菌群落多样性研究   总被引:1,自引:0,他引:1  
为了揭示连作对龙牙百合和铁炮百合根际土壤细菌群落结构和多样性的影响,本文采用高通量测序技术对连作2年、正茬的龙牙百合和铁炮百合根际土壤细菌群落进行16SrDNA基因V3+V4区域测序。结果显示:4个百合根际土壤样品中的有效序列注释为14068个操作分类单元(OTUs)。α多样性指数表明,连作提高了龙牙百合根际土壤细菌群落的丰度和多样性,降低了铁炮百合根际土壤细菌群落的丰度和多样性。β多样性分析表明,连作、正茬的龙牙百合和铁炮百合之间的根际土壤细菌群落多样性差异相对较大。细菌在门、属水平的相对丰度气泡图分析表明,龙牙百合和铁炮百合的根际土壤细菌群落优势菌门都主要有变形菌门、绿弯菌门、酸杆菌门、放线菌门、拟杆菌门。伯克霍尔德菌属、玫瑰弯菌属、芽单胞菌属、未命名Chloroflexi_bacterium属分别是正茬、连作2年的龙牙百合和铁炮百合根际土壤细菌群落的最优势菌属。连作2年后变形菌门、拟杆菌门菌群丰度的下降以及绿弯菌门菌群丰度的升高可能是铁炮百合更耐连作的原因,连作2年后变形菌门、拟杆菌门菌群丰度的升高以及酸杆菌门、放线菌门菌群丰度的下降可能是龙牙百合不耐连作的原因。研究结果对揭示百合连作障碍形成的原因具有一定参考价值。  相似文献   

4.
海口东湖降解磷细菌研究初报   总被引:2,自引:0,他引:2  
对海口东湖磷细菌研究的结果表明:至少有芽孢杆菌属等13个属的不同菌株以其对磷化合物的分解能力推动着湖泊中磷的循环;在以芽孢杆菌属,假单孢菌属,微球菌属为优势的菌属中,假单孢菌属的解磷能力最强。  相似文献   

5.
虫生真菌的生物防治研究进展   总被引:1,自引:0,他引:1  
首先从虫生真菌的资源分布论述,在我国已发现的昆虫病原真菌涉及40多个属400多种,其中虫草属真菌80种,捕食和寄生线虫的真菌10种,寄生昆虫的真菌215种,报道的新种有24种,生物防治中应用较广主要为绿僵菌、白僵菌和蜡蚧轮枝菌等;其次概述了入侵及致病机制,虫生真菌的入侵主要分四个阶段,入侵是机械压力和酶共同作用的结果.最后对毒力稳定性,菌株来源对同种昆虫毒力往往差异较大,同一菌株对不司寄主或同一寄主不同虫龄的毒力也有所不同.介绍了虫生真菌的发展的历史、研究现状与展望,对近年来我国虫生真菌的生物防治研究进展也进行了概括.  相似文献   

6.
为了挖掘大葱紫斑病生防资源,研究采用培养法从大葱叶际分离细菌,然后用对峙培养法筛选大葱紫斑病菌生防细菌.结果表明:大葱叶际细菌群落中嗜甲基单胞菌、鞘氨醇单胞菌属、微杆菌属、假单胞菌属于优势细菌类群.从中筛选出1株对大葱紫斑病菌具有较好拮抗活性的菌株X85,经形态特征和16S rDNA序列鉴定为亚麻假单胞菌.田间试验表明...  相似文献   

7.
利用荧光假单胞杆菌(Pseudomonas fluorescens)WCS374r、WCS417r、Q2-87、2-79和CHAOr,恶臭假单胞杆菌(P.putida)WCS358r菌株及其转基因菌株WCS358::phl和WCS358::Phz,以及绿脓假单胞杆菌(P.aeruginosa)7NSK2及其相应的嗜铁素突变体,采用预先接种和混合接种两种方法开展了板粟疫病的生物防治试验.在对板栗疫病菌的拮抗活性测定中,所用生防菌对其孢子萌发和菌丝的生长有不同程度的抑制作用,其中以能产生嗜铁素的WCS358r等菌株,优于其嗜铁素缺失突变体,说明嗜铁素是抑制板栗疫病菌孢子萌发的有效因子.在生物防治试验中,WCS358r对板栗疫病有较好的防治效果,其嗜铁素缺失突变体JM218却没有效果,其转基因菌株WCS358::phl的发病率与WCS358r接近,说明细菌产生的嗜铁素有一定的防治作用,而细菌产生的抗生素DAPG没有防治效果.混合接种比预先接种防治效果提高了10%左右.  相似文献   

8.
《商洛学院学报》2019,(6):18-25
采用组织块分离法,从采自商洛的野生艾蒿根、茎和叶中分离到54株内生菌,其中35株细菌,19株真菌。以金黄色葡萄球菌、枯草芽孢杆菌、大肠杆菌为供试靶标菌,采用纸片法对分离的艾蒿内生细菌进行了拮抗活性的筛选,以棉花枯萎病菌、烟草赤星病菌、茄病镰孢霉为植物病原菌,用对峙法对内生真菌的拮抗活性进行了筛选。结果表明:分离到的内生细菌和真菌在野生艾蒿中的数量分布均表现为在根中最多,茎中次之,叶中最少。从内生细菌中筛选出了4株具有较强拮抗活性的菌株,分别是BS-6和BR-6菌株对枯草芽孢杆菌有较强拮抗作用,BR-9和BS-12菌株对大肠杆菌有较强拮抗作用;从内生真菌中筛选到2株对植物病原菌具有拮抗活性的菌株,分别是FS-8菌株对棉花枯萎病菌有较强的拮抗作用,FR-4菌株对茄病镰孢霉具有明显的拮抗作用。由此可见,野生艾蒿组织中内生菌含量较为丰富,而且其中存在对细菌和植物病原菌具有较强拮抗活性的菌株,其内生菌资源应进一步开发利用。  相似文献   

9.
肉桂挥发油抗菌活性研究   总被引:3,自引:0,他引:3  
采用琼脂平板二倍稀释法测定了肉桂挥发油对11种62株临床分离细菌和5株白假丝酵母真菌临床分离株的最低抑菌浓度,统计分析了它们对金黄色葡萄球菌、大肠埃希菌、肺炎克雷伯菌、铜绿假单胞菌和白假丝酵母菌等共5个种属的MIC50和MIC90,采用单因素方差分析法比较分析了肉桂挥发油分别对金黄色葡萄球菌、大肠埃希菌、肺炎克雷伯菌、铜绿假单胞菌和白假丝酵母菌共5个种属菌株抑菌活性的强弱.结果表明,肉桂挥发油对所有受试细菌和真菌均有较强的抗菌活性,最低抑菌浓度(MIC)为0.071.11mg/mL,且对耐药菌株和敏感株有相同的抗菌活性.肉桂挥发油对金黄色葡萄球菌、大肠埃希菌和肺炎克雷伯菌的抑菌活性无明显统计学差异(P>0.05);对铜绿假单胞菌的抑菌活性明显低于对金黄色葡萄球菌和大肠埃希菌的活性(P<0.01);对白假丝酵母真菌的活性均明显强于金黄色葡萄球菌、大肠埃希菌、肺炎克雷伯菌和铜绿假单胞菌(P<0.01).  相似文献   

10.
为探究4种落叶果树土壤根际真核生物结构多样性,对石榴、桃树、银杏、樱桃土壤根际真核生物结构的多样性进行测序、分析。共得到2 368个OTUs,银杏样品的辛普森指数相对较低,香农指数相对较高,显示该样品群落多样性相对较高,银杏样品的ACE指数和Chaol指数都比其他样品高,表明银杏样品群落丰富度相对较高。在属水平上,石榴样品真菌群落有4个真菌优势菌属,主要是毛壳菌属(18.68%)和镰刀菌属(6.77%)。桃树样品真菌群落有5个真菌优势菌属,主要是镰刀菌属(8.87%)和毛壳菌属(7.00%)。樱桃样品真菌群落有6个真菌优势菌属,主要是毛壳菌属(22.66%)、镰刀菌属(15.91%)及被孢霉属(11.16%)。银杏样品真菌群落有7个真菌优势菌属,主要是毛壳菌属(9.08%)和Parastagonospora(5.83%)。4种果树样品的优势类群主要是真菌,不同果树样品根际土壤真菌群落差异较大。  相似文献   

11.
从楚雄采集核桃样品,进行内生真菌的分离、纯化及鉴定。以德氏孺孢、链格孢、疫霉、拟盘多毛孢和灰葡萄孢为指示菌,对分离菌株进行了抗菌活性筛选。结果显示,从核桃内生真菌根、茎和叶中共分离得到22株内生真菌,分别属于6个属,其中,青霉属和镰孢属为优势类群。抗菌活性研究结果表明,有四个核桃内生真菌菌株(青霉属2株、镰孢属2株)对链格孢有抑菌作用,且抑菌效果较明显。其中属于青霉属的cx13和属于镰孢属的cx09对多种病原菌具有抑菌作用。  相似文献   

12.
This research was aimed at isolating and identifying the predominant lactic acid bacteria (LAB) in the traditional Chinese salt-fermented soybean food, douchi, from Yunnan, China. The predominant LAB present were isolated and identified by conventional culture-dependent methods combined with molecular biological methods. Two hundred and sixty isolates were obtained from thirty kinds of traditional fermented douchi from six cities and counties in Yunnan, and those strains were divided into twelve groups by their morphological and biochemical characteristics. Based on 16S ribosomal DNA (rDNA) sequencing and analysis, 56 representative strains were identified as belonging to 6 genera and 14 species: Lactobacillus (4 spp.), Weissella (3 spp.), Pediococcus (2 spp.), Staphylococcus (2 spp.), Enterococcus (1 sp.), and Bacillus (2 spp.). The results show that douchi contains a large natural population of LAB of diverse composition from which some strains could be selected as starters for functional fermented foods. This is the first study on the original douchi from Yunnan, and the results suggest that it may be a useful source for the isolation of LAB. This study has also laid a foundation for further research on developing functional douchi products.  相似文献   

13.
一株互花米草耐重金属内生菌的分离及其特性分析   总被引:1,自引:0,他引:1  
利用微生物分离培养方法从互花米草根部和叶片获得内生细菌,经重金属筛选,分离到一种耐受重金属Cu2+、Pb2+和Cr6+的细菌.为了进一步鉴定分离菌株,利用 PCR 方法扩增其部分16S rDNA 序列,目标DNA条带约1500 bp,测序和在线分析结果后显示,所测序列均与基因库中已上传的 Lysinibacillus sphaericus菌株16S rDNA 序列(KJ878614.1,JN613478.1)相似性均为100%.初步鉴定该菌为 Lysinibacillus属球形芽孢杆菌(Lysinibacillus sphaericus),命名为Lysinibacillus sphaericus QZ1-1.对该菌株采用促生长特性分析结果显示,该菌株具有产生 IAA和 ACC的能力,同时该菌能在无氮培养基中生长,具备固氮功能,为日后重金属污染生物修复相关研究提供了良好的目标菌株.  相似文献   

14.
INTRODUCTIONRiceseedharborsadozenofplantpathogen icbacteria (Gotoetal.,1 988;Xieetal.,1 998) .Thebacterialpathogenscausearangeofricediseases,someverydestructivewhileothershavenoeffectonricecropgrowth .Inthisstudy ,wefoundalargenumberofbacteriaasso ciatedw…  相似文献   

15.
为了调查唐山大清河盐场的中度嗜盐菌资源,采集晒盐场的盐泥进行嗜盐菌的分离纯化,并进行形态学观察、生理生化特征鉴定和功能酶筛选。结果分离得到14株中度嗜盐菌。这些嗜盐菌的菌落呈黄色或者乳白色,较小,不透明,边缘整齐;细菌多呈杆状,革兰氏染色均呈阴性。生理生化特征鉴定显示,14株菌株中的3株甲基红试验阳性,3株伏-普试验阳性,3株可分解含硫的氨基酸,5株可利用柠檬酸作为碳源。多株菌可释放功能酶,其中6株产淀粉酶,7株产纤维素酶,7株产脂肪酶和6株产蛋白酶。该研究虽然仅获取了少量的中度嗜盐菌,但为开发利用唐山大清河盐场的嗜盐菌资源提供了参考。  相似文献   

16.
目的:回顾性的分析某医院重症监护室(ICU)2012年1月1日至2012年12月31日之间感染病原菌的分布及其耐药情况。方法:用VITET-2Compact60全自动微生物分析仪鉴定细菌,K—B纸片扩散法做体外药敏试验,统计、分析细菌的检出率和药敏结果。结果:799份ICU标本,医院感染分离菌株249株,检出率31.16%。首位是洋葱伯克霍尔德菌(60株,24.10%),其次鲍曼不动杆菌(55株,22.09%),第三是肺炎克雷伯菌(39株,15.66%)。分离菌中标本来源痰和咽拭子最常见,其次静脉血、静脉导管。洋葱假单胞、鲍曼不动杆菌、铜绿假单胞菌、肺炎克雷伯菌、大肠埃希菌、人葡萄球菌及金黄色葡萄球菌对多种抗菌药物均具有较高的耐药性。结论:医院感染病原菌中以非发酵菌的检出率最高,其次是肺炎克雷伯菌并且耐药性强。因此治疗医院感染病原菌所致的感染性疾病应根据体外药敏试验结果选用敏感的抗菌药物,减低耐药率。  相似文献   

17.
INTRODUCTIONThecombustionoffossilfuelsgeneratesSO2andNOxpollutantscausingairpollutionandacidrain.Existingfluegasdesulfurization(FGD)scru-bbersareefficientforcontrollingSO2emission,butareincapableofremovingwater-insolublenitricoxide.WeandotherresearcheshadreportedtheuseofmetalchelateadditivesinFGDsystemsforcom-binedremovalofNOxandSO2(Shietal.,1996a;1996b;1996c;1997;LittlejohnandChang,1990;Tsaietal.,1989;Harriottetal.,1993).FeII(EDTA,ethylenediaminetetraacetate)isoneofthemostprom…  相似文献   

18.
Ferrous chelate absorption is deemed a promising method for NO removal from flue gas, but the key problem is the difficulty to regenerate the absorption solution, i.e. the complexes of FeⅡ(EDTA)NO and FeⅢ(EDTA) in the solution. Two bacterial strains isolated recently from the sludge of the denitrification step of a municipal wastewater treatment plant could be applied effectively to regenerate the absorbent were Pseudomonas sp. and klebsiella trevisan sp. Pseudomonas sp. exhibited high reduction ability on FeⅡ(EDTA)NO and the klebsiella trevisan sp. was more suitable for FeⅢ(EDTA) reduction.  相似文献   

19.
Medicinal plants have been used by marginal communities to treat various ailments. However, the potential of endophytes within these bio-prospective medicinal plants remains unknown. The present study elucidates the endophytic diversity of medicinal plants (Caralluma acutangula, Rhazya stricta, and Moringa peregrina) and the endophyte role in seed growth and oxidative stress. Various organs of medicinal plants yielded ten endophytes, which were identified as Phoma sp. (6 isolates), Alternaria sp. (2), Bipolaris sp. (1), and Cladosporium sp. (1) based on 18S rDNA sequencing and phylogenetic analysis. The culture filtrates (CFs; 25%, 50%, and 100% concentrations) from these endophytes were tested against the growth of normal and dwarf mutant rice lines. Endophytic CF exhibited dose-dependent growth stimulation and suppression effects. CF (100%) of Phoma sp. significantly increased rice seed germination and growth compared to controls and other endophytes. This growth-promoting effect was due to the presence of indole acetic acid in endophytic CF. The gas chromatography/mass spectrometry (GC/MS) analysis showed the highest indole acetic acid content ((54.31±0.21) μmol/L) in Bipolaris sp. In addition, the isolate of Bipolaris sp. exhibited significantly higher radical scavenging and anti-lipid peroxidation activity than the other isolates. Bipolaris sp. and Phoma sp. also exhibited significantly higher flavonoid and phenolic contents. The medicinal plants exhibited the presence of bio-prospective endophytic strains, which could be used for the improvement of crop growth and the mitigation of oxidative stresses.  相似文献   

20.
With the use of a seed washing technique, more than 4000 Gram negative bacteria were isolated by two improved isolation methods from 446 batches of 1 kg rice seed samples obtained from 22 provinces in the Philippines. They were initially characterized on the basis of colony morphology and results of biochemical and pathogenicity tests. Six hundred and fifty-two strains were further identified by Biolog, from which 133 were selected for fatty acid methyl ester (FAME) analysis together with 80 standard reference! strains. Six-teen species or types ofPseudomonas and 17 genera of non-pseudomonads were identified, more than one third of which have not been recorded in rice. The most predominant species observed wereP. putida andP. fulva. About 17% of the strains ofPseudomonas and 2% of the non-pseudomonads were antagonistic to one or more fungal or bacterial pathogens of rice. Rice seed is an important source of biological control agents. Project supported by Belgium government and Asia Development Bank. Part of the experiments conducted at the University of Gent, Belgium and IRRI during 1997–2000.  相似文献   

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