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1.
西瓜细菌性果斑病研究进展 总被引：14，自引：2，他引：14
西瓜细菌性果斑病是由类产碱假单胞菌西瓜亚种〔Pseudomonas pseudoalcaligenes subsp. citrulli (Schaad et al. 1978)〕所引起，1992年该病菌改名为燕麦食酸菌西瓜亚种〔Acidovorax avenae subsp. citrulli (Willems et al. 1992) 〕。革兰氏阴性菌，属rRNA组I。不产生荧光和其他色素，单根极生鞭毛，严格好氧。不产生精氨酸水解酶，能在41℃下生长，但不能在4℃生长，明胶液化力弱，氧化酶和2－酮葡糖酸试验阳性。利用葡萄糖和蔗糖作碳源结果不一致；但利用β－丙氨酸、柠檬酸盐、乙醇、乙醇胺、果糖、L－亮氨酸和D－丝氨酸结果一致… 相似文献
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对分离自西北地区6个矿区采样点的68株天蓝苜蓿根瘤菌进行了生理生化特性和16S rDNA PCR-RFLP分析.唯一碳源利用结果表明:供试菌株均能利用丁二酸钠等7种碳源,均不能利用马尿酸钠等4种碳源.在苯酚作为唯一碳源的培养基上生长试验表明:所有菌株可以在400 mg/L的苯酚培养基上生长;5株菌可以在700 mg/L浓度下生长;所有菌株都不能在800 mg/L浓度以上的苯酚培养基上生长.重金属耐受性结果表明:供试菌株对重金属有不同程度耐受性,筛选出1株具有优良重金属耐受性的菌株CCNWGS0037.16S rDNA PCR-RFLP分析结果表明:所有菌株可以分为3种类型,全序列测定结果分析表明分别属于中华根瘤菌属(Sinorhizobium)、根瘤菌属(Rhizobium)和土壤杆菌属(Agrobacterium).综合分析,矿区天蓝苜蓿根瘤菌多样性比较单一. 相似文献
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芝麻立枯病内生生防细菌的筛选 总被引：2，自引：0，他引：2
利用表面消毒涂布平板的方法从大田健康芝麻根内分离芝麻内生细菌399株。平板对峙试验结果显示,176株细菌对立枯丝核菌(Rhizoctonia solani)有不同程度的拮抗能力,其中编号为B16、b10、D31、e23、G10、I10的6个菌株在PDA平板上对于立枯丝核菌具有极强的抑制作用,对西瓜枯萎病菌、西瓜炭疽病菌、小麦全蚀病菌和油菜菌核病菌也表现出广谱的抑菌作用。利用胶体几丁质和胶体壳聚糖作为唯一碳源,测定了上述6株细菌产生几丁质酶和壳聚糖酶的能力,发现b10和G10具有产壳聚糖酶的能力,I10有产几丁质酶的能力。活体盆栽试验测定了上述6株细菌对芝麻立枯病的生防效果,结果显示测定的6株细菌均具有一定的防治效果,其中G10的生防效果最好,可达到52%。利用胶体壳聚糖作为唯一碳源的选择性培养基测定了G10菌株在芝麻根系内部的定殖动态,发现G10在芝麻根部可以长期定殖。 相似文献
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稻区杂草上的梨孢菌与稻瘟病发生的关系 总被引：5，自引：0，他引：5
新发现的稻曲病菌白化菌株其分生孢子座白色,厚垣孢子表面光滑,大小为3.5-6.0×3.5-6.8μm。在麦芽糖-稻芽浸渍液中可产生较多的分生孢子。pH值为6时生长最好。普通培养基中加入几种供试碳源和氮源均有利于菌落生长,以蔗糖为碳源,浓度为2%或以L-天门冬酰胺为氮源浓度为0.2%~0.3%时时其菌落生长有促进作用。培养过程中可产生对稻种萌发有抑制作用的毒素,而固体培养时产毒能力高于液体培养。白化菌株回接到水稻上可重新产生白色稻曲球。该菌和稻曲病菌的酯酶同功酶和RAPD扩增谱带明显不同。可见白化菌株具有独立于稻曲病菌的新的分类地位。 相似文献
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刀孢蜡蚧菌Lecanicillium psalliotae是一种重要的昆虫病原真菌,在害虫生物防治中应用广泛。为明确刀孢蜡蚧菌生长和产孢的最适培养条件,本文对一株刀孢蜡蚧菌HFLP006菌株的培养条件进行优化,比较了不同培养基种类、初始接菌量、培养温度、供试碳源和氮源对该菌株产孢量的影响。结果表明,在SDAY液体培养基中,以8%接菌量培养8 d能够获得最大产孢量2.83×109个孢子/mL。菌株HFLP006最适产孢温度为26℃。以甘露醇和葡萄糖为碳源能够获得最大产孢量,分别为1.28×109和1.25×109个孢子/mL,二者之间差异不显著。以酵母浸粉为氮源获得的产孢量（9.48×108个孢子/mL）最大,且显著高于其他氮源处理组。使用1×107个孢子/mL的菌悬液对桃蚜进行毒力测定,处理后第7 d试虫平均校正死亡率达80.73%。本研究所获得的结果对菌株HFLP006的大规模工业生产和生物防治应用均具有重要意义。 相似文献
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为了明确青枯菌无致病力菌株FJAT-1458的生防竞争机制，本研究采用体外共培养方法研究了碳源、氮源和培养时间对菌株FJAT-1458和青枯菌强致病力菌株FJAT-91竞争生长的影响；同时，研究了菌株FJAT-1458和FJAT-91在番茄植株体内的竞争生长。结果表明，碳源含量低于20%时，菌株FJAT-1458不能生长，而菌株FJAT-91可生长；无氮源条件下，FJAT-1458和FJAT-91均不能生长；碳源和氮源含量达100%时，FJAT-1458的菌体浓度（2.16×109 cfu/mL）显著低于FJAT-91的菌体浓度（3.24×109 cfu/mL）。混合培养24 h前，FJAT-1458生长量大于FJAT-91，24 h后则相反。在单独接种或混合接种5 d后，FJAT-1458和FJAT-91均在番茄植株体内出现最大定殖量，随后迅速减少；FJAT-91在单独接种15 d时，定殖数量为0；两种菌株单独接种的定殖数量均大于混合接种（接种15 d除外）。先接种FJAT-1458，3 d后接种FJAT-91对番茄青枯病的防效（100%）显著高于同时接种FJAT-1458和FJAT-91（74.67%）。本研究表明，在体外无致病力菌株FJAT-1458对碳源和氮源的营养竞争能力弱于强致病力菌株FJAT-91；在体内无致病力菌株FJAT-1458会抑制强致病力菌株FJAT-91的生长；因此，FJAT-1458的生防竞争机制中，营养竞争起非主导作用，而位点竞争可能是主导因素。 相似文献
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《广西植保》2021,34(2)
微生物降解木质素具有环境友好、低成本等优点而受到广泛关注。自云斑白条天牛Batoceralineaolata (Chaevroat)幼虫肠道中筛选高效木质素降解菌,以实现木质素的资源化利用。本研究以愈创木酚为唯一碳源的选择培养基法和苯胺蓝平板法筛选高效降解木质素的菌株,采用形态学观察和16S r DNA基因序列同源性分析方法对菌株进行鉴定。在愈创木酚选择培养基上共筛选出37株细菌菌株,在苯胺蓝平板上,B01和B12菌株的水解圈D/d值最大(1.60和1.58);经鉴定,B01菌株为假单胞菌属(Pseudomonas)的一种,B12菌株为考氏科萨克氏菌属(Kosakonia)的一种。 相似文献
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试验结果证明:X.oryzae不能利用硝态氮,对氨态氮的利用能力也很差。X.protypus的菌株O-722对硝态氮和氨态氮的利用能力都很强。X.oryzicola、X.leersiae和X.protypus的菌株LS-9则介乎两者之间。若以蔗糖代替葡萄糖作碳源,则X.oryzae对铵盐的利用能力显著增强。X.oryzae对氨基酸等的要求较X.oryzicola严格。对X.oryzae生长最适宜的氨基酸是L-谷氨酸、L-门冬氨酸、L-脯氨酸和L-丙氨酸等,以L-谷氨酸最好。X.oryzicola适宜的氨基酸与上述相似,但是种类更多一些。因此,白叶枯病的发展与水稻营养状态之所以有密切的关系,这与白叶枯病细菌的营养特征有关。水稻细菌性条斑病细菌对氮肥的反应不象白叶枯病菌那样敏感,可能是条斑病细菌对氮素营养的要求不如白叶枯病细菌严格的原故。试验结果还指出,致病性强弱不同的细菌对氮素营养的要求不同,接近于腐生的弱寄生性菌(X.protypus),对硝态氮和氨态氮的利用能力都很强。因此,在一系列有亲缘关系的细菌中,随着致病性的增强,对氮素营养的要求也可能相应地更加严格。 相似文献
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根据梨火疫病菌16S~23S间的ITS保守序列,设计并合成了一对特异性引物REA/FEA,应用荧光染料SYBR Green I,对10个梨火疫的菌株和其它相关参试菌株进行了检测。结果表明,10个梨火疫菌株都产生荧光信号而其它参试菌株都不产生荧光信号,成功建立了梨火疫病菌的实时荧光PCR检测方法。整个检测过程只需3h,完全闭管,降低了污染的机会,无需PCR后处理。检测的灵敏度是4个菌体细胞,比常规PCR电泳检测提高了10倍。用该特异性引物对梨枝条浸泡液进行实时荧光PCR检测,结果可特异性检测到目标菌的存在,并且检测的灵敏度是24个菌体细胞,比常规PCR电泳检测提高10倍。 相似文献
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为获得枯草芽胞杆菌Bacillus subtilis BAB-1菌株的芽胞高效率生产技术,采用Biolog微生物细胞表型芯片(phenotype microarray,PM)技术分析了适合该菌株细胞生长的营养物质、渗透压和pH等生长环境条件;通过单因素试验分析了5种碳源及5种氮源对该菌株生长及芽胞形成的影响。结果表明,BAB-1菌株能够利用114种碳源、228种氮源、29种磷源及29种硫源作为其营养物质,其中52种碳源、66种氮源、3种硫源及1种磷源能够明显促进该菌株的细胞生长;BAB-1菌株对渗透压的忍受能力较强,在1%～10%氯化钠、3%～6%氯化钾、2%～5%硫酸钠、5%～20%乙二醇、1%～6%甲酸钠、2%～7%尿素、1%～12%乳酸钠、20～200 mmol/L磷酸钠、10～100 mmol/L硝酸钠、10～100 mmol/L硫酸铵中均能较好的生长;BAB-1菌株对pH的耐受范围较广,在4.5≤pH≤10.0条件下均能够生长。葡萄糖与氯化铵分别是最适宜BAB-1菌株生长的碳源与氮源,在不同培养时间其菌体总量均最高,48 h时该菌株的菌体总量分别达到6.90×10~8CFU/mL与6.87×10~8CFU/mL;培养12 h时,D-木糖、D-核糖、L-阿拉伯糖及熊果苷能够显著提高BAB-1菌株的芽胞形成率,其中L-阿拉伯糖与熊果苷的芽胞形成率较高,分别为61.94%与66.92%;培养12～36 h,L-脯氨酸、L-谷氨酰胺及L-天冬酰胺能够显著提高BAB-1菌株的芽胞形成率,芽胞形成率介于27.88%～82.37%之间。表明表型芯片技术可以应用于枯草芽胞杆菌生长及芽胞形成营养物质的高通量分析及培养工艺的优化中。 相似文献
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研究结果表明,水稻秆腐菌核病菌可利用多种碳源和氮源,碳源以可溶性淀粉最好,氮源以酒石酸铵最好,混合碳源(蔗糖+鼠李糖)对病菌菌丝生长有促进作用,比单独蔗糖和鼠李糖生长的好;病菌能在多种天然培养基上生长并形成菌核;菌丝在碳氮比为60∶1的培养基上生长最好;生长物质VB6+肌醇、VB6+谷氨酰胺等11个组合对菌丝生长有促进作用;微量元素中亚铁、锰和硼对菌丝生长有抑制作用;液体培养中以Czapek培养基生长最好,但不利于菌核的形成;菌核在15～35℃均可萌发,最适温度为30℃;菌核在0.05%葡萄糖溶液、蒸馏水、水琼脂上均可萌发,以0.05%葡萄糖溶液萌发最好。 相似文献
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The efficacy of N -phenylcarbamates and N -phenylformamidoximes against benzimidazole-resistant strains of Venturia nashicola was tested experimentally in Japanese pear orchards. Both compounds gave effective control when applied in an orchard where highly benzimidazole-resistant strains were predominant. However, unsatisfactory control was observed in an orchard where the fungal population was dominated by fungal strains with intermediate or weak benzimidazole resistance. Strains resistant to N -phenylcarbamates and N -phenylformamidoximes were widely distributed in Japanese pear orchards, suggesting that effective use of these compounds to control benzimidazole-resistant strains of V. nashicola would not be practicable. Increased sensitivity to N -phenylformamidoximes in highly benzimidazole-resistant isolates was shown to be controlled by a single chromosomal gene, but progenies that were highly resistant to both a benzimidazole fungicide and a N -phenylformamidoximes appeared in crosses between parents resistant to each fungicide alone. Similar strains were also found in pear orchards, and this'double resistance'was shown to be heritable. 相似文献
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ABSTRACT A comparative study was made on the host reactions, serological properties, and nucleotide sequences of the coat protein (CP) gene of 10 clover yellow vein virus (C1YVV) isolates and one bean yellow mosaic virus (BYMV) isolate collected from different host plant species and locations in Japan. Two strains of C1YVV isolates, grouped on the basis of host reactions on Chenopodium amaranticolor, C. quinoa, Nicotianaclevelandii, N. benthamiana, Vicia faba, and Trifolium repens, corresponded to two serotypes determined by double-antibody sandwich- and triple-antibody sandwich-enzyme-linked immunosorbent assay using three polyclonal and nine monoclonal antibodies. These results were also confirmed by nucleotide sequence analysis of the CP gene. The CP gene of C1YVV isolates of strain 1, including the Australian isolate C1YVV-B, had 93 to 98% nucleotide identities and 97 to 99.6% amino acid identities. The CP of C1YVV isolates of strain 2, including the New Zealand isolate C1YVV-NZ, had 92 to 98% nucleotide identities and 95 to 98% amino acid identities. The nucleotide identities and the amino acid identities between the two C1YVV strains were 82 to 84%, and 90 to 94%, respectively. When compared with the CP sequences of 12 C1YVV isolates, the CP sequence of the BYMV isolate had 71 to 73% nucleotide identity and 73 to 77% amino acid identity. Amino acid sequence differences among C1YVV isolates from strains 1 and 2 were located mostly at the N-terminal regions of the CP. Our results indicated that the C1YVV isolates studied could be separated into two strains on the basis of host reactions, serology, and the nucleotide sequence of the CP gene. 相似文献
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黄瓜花叶病毒两亚组分离物寄主反应和血清学性质比较研究 总被引：9，自引：4，他引：9
本文对枯萎病菌侵入黄瓜不同抗性品种的途径,以及黄瓜受侵染根部维管组织的变化进行了观察。分生孢子在幼根表皮上萌发产生菌丝,通过胞间层侵入表皮细胞,之后菌丝继续向内部生长,穿过皮层组织进入导管。受侵染的导管内相继出现壁覆盖物、侵填体及褐色物。抗病品种的壁覆盖物比感病品种的厚:侵填体由受侵染导管旁边的薄壁细胞产生,一个细胞可产生多个侵填体,并在侵填体中观察到细胞核的存在,感病品种中的侵填体发育不充分,抗病品种中的侵填体能完全堵塞导管;谒色物在感病、抗病品种中均能完全堵塞导管,对菌丝的侵入构成了较强的机械障碍。 相似文献
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用菌落直径法和菌丝干重法研究了查彼克（Czapek）培养基中葡萄糖、果糖、半乳糖、木糖、甘油5种碳源和硫酸铵、硝酸钠、亚硝酸钠、尿素、丙氨酸、亮氨酸、丝氨酸、脯氨酸、精氨酸、组氨酸、胱氨酸、赖氨酸12种氮源对抗戊唑醇禾谷丝核菌Rhizoctonia cerealis菌株生长的影响,以探明抗性菌株和敏感菌株之间生理适合度的差异.结果表明,在不同碳源条件下,所有菌株都在蔗糖、甘油和葡萄糖中生长最快,培养7天后,菌落直径和菌丝干重分别可达3.1750～7.5667 cm和0.0334～0.0554g,在木糖和果糖中生长相对较慢;在相同碳源条件下,高抗菌株（WWL）的生长速度小于敏感菌株（WW）和中抗菌株（WX1和WX2）,敏感菌株和中抗菌株之间的生长速度差异不明显.在不同氮源条件下,所试菌株均能较好利用硝酸盐、亚硝酸盐、精氨酸和丙氨酸,菌落直径和菌丝干重分别可达6.2～8.8 cm和0.0336～0.0543 g,不能充分利用胱氨酸,菌落直径和菌丝干重分别仅为1.4217～3.4750 cm和0.0178～0.0297 g;在同一氮源条件下,高抗菌株的生长速度小于敏感菌株和中抗菌株,而敏感菌株和中抗菌株之间差异不明显. 相似文献
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Differentiation of Xanthomonas albilineans strains with monoclonal antibody reaction patterns and DNA fingerprints 总被引：1，自引：0，他引：1
Thirty-eight strains of the sugarcane leaf scald pathogen, Xanthomonas albilineans , were compared using a series of seven species-specific monoclonal antibodies as well as genomic DNA fingerprint patterns. The strains, which were obtained from 13 countries and states in the USA, were placed in three major groups with approximately eight subgroups based on similarity of their serological reactions. The serological groupings correlated strongly with groupings based on DNA fingerprint patterns. The groups of strains that were genetically and serologically related did not necessarily come from nearby locations but were usually from widely separated regions. Thus, it appears that disease transmission occurred by means other than natural spread. The methods used in this study are useful for comparing relationships among strains of X. albilineans . A combination of the monoclonal antibodies could be used in a serodiagnostic-based method to test for the presence of leaf scald disease. 相似文献
19.
Fifty strains of Sarocladium (11 dried specimens and 39 living cultures) were examined for variation in conidial size, utilization of several carbon sources, hydrolysis of several substrates, esterase isozymes after gel electrophoresis, and secondary metabolites after thin-layer chromatography. The results showed that there was insufficient justification to maintain the separation of the genus into the two species S. oryzae and S. attenuatum; S. attenuatum is, therefore, considered a synonym of S. oryzae. Strains isolated from outbreaks of bamboo blight in Bangladesh could be distinguished from strains isolated from rice in 12 countries by pigment production in culture; a strain isolated from bamboo leaf-litter in India was identical to the rice isolates in this respect. 相似文献
20.
Vegetative compatibility of strains of Diaporthe ambigua has not previously been examined. Single ascospore and single ascus strains, originating from individual apple, pear and plum rootstocks, were paired on freshly prepared oatmeal agar to determine if vegetative incompatibility could be detected in D. ambigua . Barrage reactions were evident as black lines along the zone of mycelial contact between expanding colonies (vegetative incompatibility reaction). Strains from cankers within an area were of numerous vegetative compatibility groups (VCGs). Strains from adjacent rootstocks usually differed in VCG. D. ambigua has the ability to outcross, and does so, despite its apparent homothallic nature. DsRNA-containing strains of D. ambigua developed a broad, clear zone when paired with a dsRNA-containing strain from a different VCG. 相似文献