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1.
从沈阳玉米田土壤中分离筛选出一株细菌SY9,其代谢产物对反枝苋种子萌发具有明显抑制活性,抑制率达85%.研究发现该菌最佳摇瓶发酵培养基为NYBD,最佳培养基配方为牛肉膏15g,蔗糖10g;最佳发酵培养条件为接菌量1%、起始pH值6.5、装液量40 ml/250ml、发酵温度28℃、摇瓶培养72 h.  相似文献   

2.
枯草芽孢杆菌B02产生拮抗物质培养基及发酵条件优化   总被引:4,自引:0,他引:4  
采用单因素和均匀试验设计,通过摇瓶培养对枯草芽孢杆菌B02产生抑菌活性物质的发酵培养基和培养条件进行优化。结果表明,最适接种体培养时间为24h;优化后的培养基配方为(g/L):糊精15.5g、牛肉膏20g、胰蛋白胨4g、NaCl 11.5g、KNO311.5g、MnSO45g;适宜培养条件为:温度30℃,初始pH值范围为7-8,接种量5%,摇瓶装液量50ml/500ml,转速200r/min,最佳培养时间72h。  相似文献   

3.
产酶溶杆菌OH11菌株摇瓶发酵条件研究   总被引:2,自引:0,他引:2  
采用单因素试验法研究了温度和转速等因子对产酶溶杆菌OH11液体发酵的影响.结果表明温度以30℃为宜,转速以210r/min为宜.通过正交试验在摇瓶中以LB为基础培养基对发酵培养基进行了优化.优化后的培养基中活菌数在48h时可达到4.5×109cfh/ml,明显高于原基础培养基的结果;通过正交试验对其他发酵条件的优化结果表明,装液量40ml/250ml、发酵时间72h、接种量108cfu/ml和初始pH值7.5为最适条件.  相似文献   

4.
本研究以枯草芽孢杆菌(Bacillus subtilis)DZ1作为研究试材,通过单因子试验及正交试验,确定其适宜的摇瓶培养基及发酵条件。结果表明,培养时间、培养基及培养条件对Bacillus subtilis DZ1的活菌数影响差异显著。DZ1的最佳种龄为12h,最佳碳源和氮源分别是可溶性淀粉和酵母膏。影响枯草芽孢杆菌DZ1活菌数的主要因素为酵母膏,其次为可溶性淀粉,K2HP04和MgSO4-7H2O影响较小。DZ1的最优培养基组合为可溶性淀粉l%,酵母膏1%,K2HPO40.15%,MgS04-7H200.02%,CaCl20.01%,在此条件下,其活菌数可达44.1×10。CFU/mL。单因子试验结果表明,DZl的适宜摇瓶培养条件分别为培养基温度34℃,初始pH值7.0,摇床转速180r/min和接种量7%。  相似文献   

5.
采用单因素试验及正交试验结合的方法,优化大丽轮枝菌拮抗细菌枯草芽孢杆菌(Bacillus subtilis)12-34菌株产抗菌蛋白的发酵条件。通过单因素试验和正交试验,确定了B. subtilis 12-34菌株产抗菌蛋白的适宜碳源、氮源和无机离子,优化了培养基的组成;并对B. subtilis 12-34菌株产抗菌蛋白的发酵时间、装瓶量、接种量、培养基初始pH、摇床转速和发酵温度进行了优化。结果显示,B. subtilis 12-34菌株产抗菌蛋白的最佳培养基组成为玉米粉5%,牛肉浸膏3%,CaCl 2 0.10%,KCl 0.05%;B. subtilis 12-34菌株产抗菌蛋白的最佳发酵条件为培养基初始pH9.0,种子液按10%接种量接种至50 mL/250 mL三角瓶中,200 r/min,37 ℃培养48 h。优化后表征抑菌蛋白产量的抑菌圈直径增大了115.5%。  相似文献   

6.
从黑龙江省漠河多年永冻土层采集的冻土样品中分离的拮抗菌解淀粉芽胞杆菌Bacillus amyloliquefaciens MH71,对多种植物病原真菌和细菌具有较强的拮抗作用.本研究主要以无菌滤液对番茄灰霉病菌的抑菌活性为检测指标,采用单因素试验筛选菌株MH71的最佳产抗菌物质培养基及最佳碳源、氮源和无机盐,运用Minitab软件,通过Box-Benhnken试验及响应面分析相结合的方法对该菌株产抗菌物质的发酵培养基配方和摇瓶发酵条件进行了优化.结果表明,菌株MH71产抗菌物质最佳培养基组成为玉米粉36.6 g/L、牛肉膏3.2 g/L、NaC1 1.33 g/L、葡萄糖14 g/L、蛋白胨7 g/L、MgSO4 0.4 g/L、K2HPO4 0.8 g/L、GaGO3 8 g/L.最适发酵条件为培养温度30℃、摇床转速200 r/min、发酵起始pH 7.0、接种量3%、装液量100 mL/500 mL、发酵时间为72 h.在最佳培养基和培养条件下,菌株MH71的活菌数达到了2.1×109 CFU/mL,芽孢数为1.2×109 CFU/mL,同时对番茄灰霉病菌的抑菌能力较优化前提高了37.4%.  相似文献   

7.
致病杆菌D43菌株产素培养基及发酵条件   总被引:6,自引:0,他引:6  
对致病杆菌产生抗生素的发酵培养基和发酵条件进行了研究,同时对该菌代谢过程pH值、还原糖、总糖、氨基氮与抗生素产量的关系进行了分析。通过筛选,确定了对该菌产素有利的碳源、氮源和无机盐。用正交试验初步确定了该菌产素的最佳发酵培养基和条件为(g/L):麦芽糖5g,牛肉胨10g,牛肉膏5g,CaCl25g,KNO30.2g。发酵培养基的起始pH值在6.0~8.0、种龄16h、摇瓶装量25—150ml/500ml的条件下,培养72h可获得较高的抗生素产量。产素量与菌代谢过程中pH、还原糖、总糖和氨基氨的变化有一定关系。通过培养基和培养条件的研究使该菌的产抗生素能力提高了46.67%。  相似文献   

8.
为探讨暗黑链霉菌Streptomyces atratus PY-1液体摇瓶发酵条件,提高其活性次级代谢产物的产量,以菌体生物量和发酵液抑制葡萄霜霉病菌Plasmopara viticola活性为指标,采用单因子试验和正交试验对菌株PY-1的最适发酵培养基成分及发酵条件进行优化。结果表明,菌株PY-1最适发酵培养基为玉米粉50 g/L、葡萄糖5 g/L、蛋白胨5 g/L、氯化铵5 g/L、氯化钠 0.5 g/L;最佳发酵培养条件为培养温度28 ℃、培养时间5 d、初始pH 7.0、250 mL三角瓶装液量90 mL、接种量体积分数5%、摇床转速180 r/min。在最佳发酵培养基和培养条件下,菌株PY-1发酵液抑菌率达到99.26%,抑菌能力提高8.35%。  相似文献   

9.
本文研究了拮抗细菌吡咯伯克霍尔德氏菌Burkholderia pyrrocinia菌株JK-SH007产抗菌物质的最佳发酵条件及其对杨树溃疡病的野外防治效果。结果表明,牛肉膏、蛋白胨是发酵培养基中最佳营养物质,有利于菌株JK-SH007抗菌物质的产生;培养基初始pH、培养时间、温度、培养体积、不同牛肉膏、蛋白胨组合等对菌株生长及其抗菌物质的产生有明显的影响,初始pH7、牛肉膏2g、蛋白胨20g、以1/2装液量装液、30℃振荡培养36h可获得较高产量的胞外分泌型抗菌物质;菌株JK-SH007的发酵液对杨树溃疡病的野外防效可达40.54%。  相似文献   

10.
生防菌株Men-myco-93-63发酵培养条件研究   总被引:1,自引:0,他引:1  
对生防链霉菌Men-myco-93-63进行了摇瓶培养条件试验。结果表明,培养温度30℃,培养基初始pH值7.5,500ml三角瓶装液100ml,摇床转速200r/min为最适摇瓶发酵培养条件。在优化的培养条件基础上进行了摇瓶中代谢情况的测定,并在摇瓶试验的基础上进行了30L发酵罐试验,为进一步发酵规模化生产奠定了基础。  相似文献   

11.
Fifteen species of dermestid beetles were recorded at ‘Evolution Canyon’ (EC), Lower Nahal Oren, Mt. Carmel, Israel. They represent ~35% of known Israeli dermestid species. The following three species were recorded for the first time in Israel:Trogoderma svriaca Dalla Torre, 1911;Ctesias svriaca Ganglbauer, 1904; andAnthrenus (s.str.) jordaniens Pic, 1934. Adults of 13 species were collected on the more solar radiated, warmer and climatically more fluctuating south-facing slope (SFS); ten species were collected on the opposite, north-facing slope (NFS), which was cooler and climatically more stable. The abundance of adult dermestid beetles was 1.9 times higher on the SFS than on the NFS (86 and 47, respectively). Species richness and abundance distribution at EC (three collecting stations on each slope and one at the valley bottom) were significantly negatively correlated with the plant cover that consisted of trees and bushes (Spearmanr s ,P=0.007 and 0.039, respectively) and perennials (Spearmanr s ,P=0.039 and 0.077, respectively), indicating that non-woody plants were preferred by adult dermestid beetles.  相似文献   

12.
Recent data on the epidemiology of the common mycotoxigenic species of Fusarium, Alternaria, Aspergillus and Penicillium in infected or colonized plants, and in stored or processed plant products from the Mediterranean area are reviewed. Emphasis is placed on the toxigenicity of the causal fungal species and the natural occurrence of well known mycotoxins (aflatoxins, ochratoxins, fumonisins, trichothecenes, zearalenone, patulin, Alternaria-toxins and moniliformin), as well as some more recently described compounds (fusaproliferin, beauvericin) whose toxigenic potential is not yet well understood. Several Fusarium species reported from throughout the Mediterranean area are responsible of the formation of mycotoxins in infected plants and in plant products, including: Fusarium graminearum, F. culmorum, F. cerealis, F. avenaceum, F. sporotrichioides and F. poae, which produce deoxynivalenol, nivalenol, fusarenone, zearalenone, moniliformin, and T-2 toxin derivatives in wheat and other small grains affected by head blight or scab, and in maize affected by red ear rot. Moreover, strains of F. verticillioides, F. proliferatum, and F. subglutinans, that form fumonisins, beauvericin, fusaproliferin, and moniliformin, are commonly associated with maize affected by ear rot. Fumonisins, were also associated with Fusarium crown and root rot of asparagus and Fusarium endosepsis of figs, caused primarily by F. proliferatum. Toxigenic A. alternata strains and associated tenuazonic acid and alternariols were commonly found in black mould of tomato, black rot of olive and citrus, black point of small cereals, and black mould of several vegetables. Toxigenic strains of A. carbonarius and ochratoxin A were often found associated with black rot of grapes, whereas toxigenic strains of A. flavus and/or P. verrucosum, forming aflatoxins and ochratoxin A, respectively, were found in moulded plant products from small cereals, peanuts, figs, pea, oilseed rape, sunflower seeds, sesame seeds, pistachios, and almonds. Finally, toxigenic strains of P. expansum and patulin were frequently found in apple, pear and other fresh fruits affected by blue mould rot, as well as in derived juices and jams.  相似文献   

13.
The genera ofMicrogaster Latreille 1804 andHygroplitis Thomson 1895 from China are presented systematically in this paper. Thirty-two species ofMicrogaster and three species ofHygroplitis are known in China. Diagnosis, character variation, distribution and host of each species among the two genera are presented, including its host and distribution. Keys to the species ofMicrogaster andHygroplitis are given. http://www.phytoparasitica.org posting Dec. 19, 2006.  相似文献   

14.
Plant Viruses Transmitted by Whiteflies   总被引:18,自引:0,他引:18  
One-hundred and fourteen virus species are transmitted by whiteflies (family Aleyrodidae). Bemisia tabaci transmits 111 of these species while Trialeurodes vaporariorum and T. abutilonia transmit three species each. B. tabaci and T. vaporariorum are present in the European–Mediterranean region, though the former is restricted in its distribution. Of the whitefly-transmitted virus species, 90% belong to the Begomovirus genus, 6% to the Crinivirus genus and the remaining 4% are in the Closterovirus, Ipomovirus or Carlavirus genera. Other named, whitefly-transmitted viruses that have not yet been ranked as species are also documented. The names, abbreviations and synonyms of the whitefly-transmitted viruses are presented in tabulated form together with details of their whitefly vectors, natural hosts and distribution. Entries are also annotated with references. Whitefly-transmitted viruses affecting plants in the European–Mediterranean region have been highlighted in the text.  相似文献   

15.
Broad bean mottle virus (BBMV) was transmitted from infected to healthy faba-bean plants by the curculionid weevilsApion radiolus Kirby,Hypera variabilis Herbst,Pachytychius strumarius Gyll,Smicronyx cyaneus Gyll, andSitona lineatus L. The latter appeared to be an efficient vector: acquisition and inoculation occurred at the first bite, the rate of transmission was c. 41%, and virus retention lasted for at least seven days.S. lineatus transmitted the virus from faba bean to lentil and pea, but not to the three genotypes of chickpea tested. This is the first report on the generaHypera, Pachytychius, andSmicronyx as virus vectors, and onA. radiolus, H. variabilis, P. strumarius, andS. cyaneus as vectors of BBMV.Out of 351 samples of food legumes with symptoms suggestive of virus infection, 16, 11, 19, and 17% of the samples of chickpea, lentil, pea, and common bean, respectively, were found infected when tested for BBMV in DAS-ELISA. This is the first report on the natural occurrence of BBMV in chickpea, lentil, pea, and common bean. The virus should be regarded as a food-legume virus rather than a faba-bean virus solely, and is considered an actual threat to food legume improvement programmes.  相似文献   

16.
A collection of 38 PVY isolates from seed potato batches, originating from several Western European countries, was characterized by using current biological, serological and molecular tools differentiating PVY strains and groups. The correlation between the three kinds of tests was good but not absolute. No single serological or PCR method was able to discriminate among the five isolate groups found. Twenty-nine isolates belonged to the PVYN strain and six to the PVYO strain. No PVYC was found. Two other isolates reacted serologically like PVYO, but were unable to elicit a hypersensitive response from the Nytbr gene and probably represent the PVYZ group. At the molecular level, these two isolates showed a combination of both PVYO and PVYN and could be recombinants of these strains. Another isolate reacted serologically like PVYO, but induced vein necrosis in tobacco, like PVYN-Wilga. Some PVYN isolates caused tuber ring necrosis in glasshouse conditions. These might belong to the PVYNTN group. The PVYNTN, PVYN-Wilga and PVYZ groups probably represent pathotypes within strains PVYN and PVYO, respectively. The present study also confirms previous reports showing a high genetic variation at the 5 end within the PVYN strain.  相似文献   

17.
The phenology of the autumn leafroller,Syndemis musculana, a local pest of apple, was studied in order to forecast larval emergence. From 1983–1986, peak flight as determined with sexpheromone traps was always between 13–18 May. The duration of embryonic development was determined at various constant temperatures and used to estimate the periods of egg hatch in these four years. Each year, most eggs should have hatched in the second decade of June.Differences in attack rates between apple cultivars seem to be explained largely by the variation in picking time. Larvae are only half grown at the beginning of harvest (cv. James Grieve), and have gone into hibernation when the latest variety (cv. Golden Delicious) is picked. Moreover, the varieties Cox's Orange Pippin and Belle de Boskoop, picked about half time, are liable to receive additional damage by caterpillars brought with the picked fruits into storage.Various hymenopterous parasites were reared from caterpillars. As the only leafroller in the orchard which hibernates as mature larva,S. musculana may promote winter survival of some parasitoids, like the eulophidColpyclypeus florus.Samenvatting De fenologie van de herfstbladroller (Syndemis musculana Hübner), een incidentele plaag op appel, werd nader bepaald met het doel het uitkomen van de eieren te kunnen voorspellen. In 1983–1986 viel de piekvlucht, bepaald met behulp van feromoonvallen, steeds tussen 13 en 18 mei.De ontwikkelingsduur van de eieren bij verschillende constante temperaturen werd gebruikt om de periode van uitkomen te schatten. De meeste eieren zullen ieder jaar in de eerste helft van juni uitkomen.Geconstateerde verschillen in schade tussen appelrassen blijken goeddeels terug te voeren op verschillen in pluktijdstip. De rupsen van de herfstbladroller zijn pas half-was als de eerste appels eind augustus geplukt worden, terwijl tegen het einde van de oogst begin oktober de meeste al in winterslaap zijn. Met name tussentijdse rassen, als Cox's Orange Pippin and Schone van Boskoop, lopen extra schade op doordat grotere rupsen met de geplukte vruchten in de kist terecht komen.Uit de rupsen werden negen, al van andere boomgaardbladrollers bekende, sluipwespen gekweekt, Omdat deze bladrollersoort, als enige in de boomgaard, als volgroeide rups overwintert, lijkt zij bij uitstek geschikt als winterwaard.This study was carried out at the Experimental Orchard De Schuilenburg, Schuilenburg 3, 4041 BK Kesteren, the Netherlands, to which address correspondence should be addressed.  相似文献   

18.
In the summer of 2004 an epidemic of sclerotinia blight of peanut, a disease caused by Sclerotinia minor, occurred in Texas in fields where the disease was never previously detected. The disease was observed on many plants within one of the fields (>3000 disease foci), although most foci were <1 m. It is hypothesized that these observations were inconsistent with the recent introduction of a monocyclic pathogen, even if disease developed under conducive environmental conditions. The pattern of disease is most suggestive of the presence of foliar (ascospore) infections, although air temperature was above the known limits for apothecia development if the pathogen had arrived in the field in 2004 peanut seed. To further examine this epidemic, 232 isolates were collected, across a variety of spatial scales spanning this field and other Texas peanut fields, and evaluated for aggressiveness, fungicide sensitivity and genotypic diversity. There was wide variation among isolates for the phenotypic characteristics measured, but there was no evidence that a genotypically unique, highly aggressive, and fungicide resistant isolate had been introduced or evolved. The predominant genotype, TX1, which contained 154 isolates, was found in every county and field population.  相似文献   

19.
In 1975 many tumours were observed in plants ofBegonia Schwabenland grown in Aalsmeer. Submersion of the roots ofNicotiana megalosiphon seedlings in a homogenate of tumorous tissue, induced tumours after two weeks. Short periods of submergence yielded results similar to those obtained after longer periods. Tumour homogenates lost their infectivity after ten min at 50°C. Aphids transmitted the infectious agent.Treatment with propylene oxide did not inhibit infectivity completely. Filtration through a 450 nm filter removed the infectious agent.Tobacco tumor virus or a viroid could not be isolated. Cultures ofCorynebacterium fascians, isolated from tumours ofN. megalosiphon were highly infectious and induced tumours in healthyN. megalosiphon andBegonia. Tumorous tissue homogenates ofPelargonium zonale, Dahlia sp.,Gladiolus sp., andLilium sp. also caused tumours inN. megalosiphon, from whichC. fascians was isolated. It was not possible to produce tumours inN. megalosiphon with homogenates from roses with symptoms of bud proliferation.Samenvatting In 1975 werden vele tumoren waargenomen inBegonia Schwabenland op Aalsmeerse bedrijven (Fig. 1). De infectiositeit van tumorweefsel kon goed en snel worden vastgesteld door de wortels van zaailingen vanNicotiana megalosiphon in een homogenaat van tumorweefsel te dompelen. Tumoren ontstonden na twee weken, de eindbeoordeling geschiedde na een maand (Fig. 2). Ook verschillende andereNicotiana spp.,Melilotus officinalis (Fig. 3) enPisum odoratum (Fig. 4) werden aangetast.Bij de infectiositeitstoets gaven zeer korte dompeltijden even goede resultaten als langere (Tabel 1). Infectieus sap verloor zijn infectievermogen na 10 min verhitting bij 50°C. Bladluizen brachten de smetstof over. Propyleenoxide verminderde de infectiositeit wel, doch onderdrukte deze niet totaal. Bij filtratie door een 450 nm filter bleef het infectieuse agens op het filter achter. Het tumor-inducerende agens was ook aanwezig in die delen van planten met tumoren welke gezond leken en het ging voor een gering deel over met zaad (Tabel 2).Uit tumoren konden wij geen tabakstumorvirus of een viroïde isoleren. Culturen vanCorynebacterium fascians, geïsoleerd uit tumoren vanN. megalosiphon bleken zeer infectieus en veroorzaakten tumoren inN. megalosiphon enBegonia. Homogenaten van tumorweefsel vanPelargonium zonale, dahlia (Fig. 5), gladiool (Fig. 6) enLilium Mid Century Hybrid Enchantment (Fig. 7) veroorzaakten ook tumoren opN. megalosiphon, waaruitC. fascians werd geïsoleerd. Met sap van kroeskopzieke rozen konden wijN. megalosiphon niet besmetten.  相似文献   

20.
Four species so far classified in Pseudocercosporella or Ramulispora (hyphomycetes) are associated with eyespot disease symptoms of cereals. Two of these have been linked to teleomorphs that were described in Tapesia. Sequence data derived from the Internal Transcribed Spacer region (ITS1, 5.8S and ITS2) of the rDNA operon showed, however, that the eyespot fungi associated with Tapesia are not congeneric with Ramulispora sorghi, the type of Ramulispora. The genus name Tapesia is now rejected in favour of the conserved name Mollisia, which appears to comprise heterogeneous fungi. Tapesia yallundae is not closely related to the type of Mollisia, M. cinerea, but clusters separately, being more closely allied to species with Cadophora anamorphs. A new holomorph genus, Oculimacula, is therefore proposed for teleomorphs of the eyespot fungi, while the anamorphs are accommodated in Helgardia gen. nov.  相似文献   

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