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2.
川芎茵核病的症状及病原菌鉴定 总被引：1，自引：0，他引：1
Symptoms of sclerotinia stem rot of Ligusticum chuanxiong were observed and the causal agent of the disease was identified. The results showed that the symptoms of this disease began with the formation of dark brown hygrophanous splotch on the basal leaves, followed by the appearance of dark brown circular spot on the basal stem. Finally, the whole plant stoped growing and died. White mycelium and/or sclerotia were formed under moisturized conditions. On PDA medium, the pathogen of this disease formed brown sclerotia with various shapes and 2-5 mm in diameter. The diameter of apothecia was 0.3-0.8 cm and the length of stipes was 2-8 cm. Asci were columniform in shape and (100-135)×9μm in size, each containing 8 ascospores sized by (6-12) μm×(3-7)μm. No asexual spore formation was observed. Based on the morphological characteristics and the sequence of ribosomal DNAITS, the pathogen was identified as Sclerotinia sclerotiorum (Lib.) de Bary. 相似文献
3.
进境豇豆种子携带种传病毒的检测与鉴定 总被引：2，自引：0，他引：2
Imported cowpea seeds were detected with growing test, ELISA assay and RT-PCR method. The ELISA results showed that cowpea seedlings with symptoms reacted positively with antibody against Southern bean mosaic virus (SBMV). The 979 bp of fragment could be amplified from two positive ELISA samples using primers specific for Southern cowpea mosaic virus (SCPMV), and the sequence determination results proved that the pathogen existing in imported cowpea seeds was SCPMV. The positive ELISA results with SBMV antibody could be further confirmed by RT-PCR amplification with specific primers designed to amplify the coat protein gene and 3' noncoding region of SCPMV and SBMV. The RT-PCR method presented here was suitable for molecular identification of SBMV and SCPMV in entry-exit plant quarantine laboratories. 相似文献
5.
棉花黄萎病拮抗细菌筛选与B-101菌株抗菌蛋白分离 总被引：3，自引：1，他引：2
The antifungal proteins of antagonistic strains NCD-2, B-101, DHT-13, BDT-25, JJ-134, JJ-102 and 80b-2 isolated from the soil infected with Verticillium dahliae were obtained from their fermentation fil-trates through precipitation with 75% ammonium sulfate salting out. Antagonistic activities of the proteins were determined via cylinder-plate method. Results indicated that antifungal proteins from 80b-2, NCD-2, DHT-13 and B-101 had higher specific activity, of which B-101 and NCD-2 could produce clear inhibition zone. Antifungal protein of B-101 strain was obtained by using the salt fractionation. It was found that protein precipitated with 20%-30% saturation ammonium sulfate could produce transparent and bigger inhibition zone, thus it had obvious antifungal activity. Furthermore the antifungal protein was separated by DEAE-cellulose chromatography. An antifungal protein fraction named RFP-6 was obtained, which showed definite inhibition activity against Verticillium dahliae. Its molecular weight was approximately 14.4 kD as determined with SDS-PAGE. 相似文献
6.
壳寡糖诱导烟草防御酶系活性变化及PR-1a基因表达研究 总被引：3，自引：0，他引：3
The activity change of defensive enzymes and PR-1a gene expression of tobacco (Nicotiana tabacum) seedling induced by chito-oligosaccharides were studied. The results showed that high level systemic acquired resistance (SAR) was expressed in tobacco plants treated with chito-oligosaccharides solution at the concentration of 50 μg/mL. PAL activity increased greatly with 2 peaks, the activity of SOD decreased initially followed by an increase with higher increment, and the activity of POD peaked early followed by a gentle fall in chito-oligosaccharide treated plants. The PR-1a gene was strongly expressed in tobacco due to systemic acquired resistance induced by chito-oligosaccharides. At 168 h after inoculation the expression quantity (co-pies/2 μL) of PR-1a gene was increased to 2 469.6 in treated tobacco leaf, reached 392.6% than that at 0 h after inoculation, it was increased 3.05 times of that in untreated control. 相似文献
7.
拮抗链霉菌B28 的分类鉴定及其生防作用研究 总被引：1，自引：0，他引：1
An antagonistic Streptomyces strain B28, isolated from the soil collected in Tianmu mountain of Zhejiang Province, was identified as Streptomyces diastatochromogenes by morphological , physiological & biochemical characteristics and 16S rDNA sequence alignment. Antagonistic study indicated that its secondary metabolite toyocamycin had an antifungal activity on the mycelial growth of seven species of plant pathogenic fungi. The results showed that toyocamycin possessed marked inhibitory activity against Rhizoctonia solani and the EC50 value was 0. 58 μg / mL. The effective of toyocamycin against Botrytis cinerea and Fusarium oxysporum f. sp. cucumerinum was much higher than that against Colletotrichum gloeosporioides, the EC50 value of
toyocamycin in inhibiting B. cinerea, F. oxysporum and C. gloeosporioides were 13. 65 μg / mL, 12. 33 μg / mL, and 30. 15 μg / mL respectively. 相似文献
8.
从水稻(Oryza sativa L.)越光根面分离到一株固氮菌株1AG4,经生理生化特性鉴定,归类为争论产碱菌(Alcaligenes paradoxus)。1AG4的固氮酶乙炔还原活性(ARA)为13.06 C2H4 nmol/ml°h,固定15N2活性(N2FA)为2.052 15N a.e.%,表明1AG4具有较强的固氮能力。平皿拮抗试验证明1AG4可拮抗包括水稻三大病害病原菌在内的14种植物病原菌(Xanthomonas oryzae pv.oryzae ZHE173、Thanatephorus cucum eris、Piricularia oryzae Cavara、Alternaria longipes(Ellis et Everhart) Tisdale etW adkins、Cochliobolus sativus、Colletotrichum agaves Cavara、Colletotrichum lagenarium(Passerini) Ellis et Halsted、Colletotrichum panacicola Uyeda et Takimoto、Fusarium oxysporum f.niveum、Helminthosporium turcicum Passerini、Phytophthora parasitica Destur、Verticillium albo-atrum Reinkeet Berthold、Phytophthora melonis Katsura、Pseudomonas solanacearum Smith)的生长 相似文献
9.
马铃薯疮痂病菌致病相关基因的克隆及表达 总被引：1，自引：0，他引：1
A pathogenic-related gene nec1 was cloned in Streptomyces scabies CPS-1, potato scab strain. Analysis results showed that the length of open reading frame(ORF) for nec1 gene was 666 bp, and the GC content was 54.2%. Sequence alignment indicated that a 650 bp up-stream sequence shared 91% similarity with IS 256 family transposase nucleotide sequences by BLASTn searches against GenBank. The segments obtained by PCR amplification were digested by enzymes SphⅠand SacⅠ, and linked to the expression vector pIJ702. The recombinants were transformed into nonpathogenicity strain Streptomyces lividans 66 TK24. Bioas-say results suggested that the transformants possessed the same symptoms as pathogenic strain on potato tuber slices and radish seedlings, which implied that nec1 gene was associated with the pathogenicity of S. scabies CPS-1. 相似文献
10.
具杀线虫活性的苏云金杆菌筛选研究 总被引：5，自引：0，他引：5
Bioassay of 51 strains of Bacillus thuringiensis to Bursaphelenchus xylophilus had been studied in laboratory. Two of them had higher toxicity to B. xylophilus. Extraction of endotoxin and exotoxin of the two isolates to B. xylophilus showed the action of exotoxin higher than that of endotoxin. 相似文献
11.
水稻条斑病(Bacterial leaf streak, BLS)由稻黄单胞菌种下的致病变种条斑病菌(Xanthomonas oryzae pv. oryzicola, Xoc)侵染引起,已成为我国南方水稻种植区的一个重要病害。为了筛选防治BLS的生防细菌,本研究以Xoc的模式菌株RS105为靶标菌,采用平板稀释和抑菌圈法,从辣椒根际土壤中分离筛选到具有拮抗活性的菌株181-7。通过形态学、生理生化特征以及16S rRNA序列分析鉴定该菌株为高地芽胞杆菌,命名为Bacillus altitudinis 181-7。针对14种植物病原细菌和3种病原真菌的拮抗谱试验发现,181-7对Xoc和水稻白叶枯病菌(X. oryzae pv. oryzae, Xoo)表现特异性的拮抗作用,对禾谷镰刀菌也具有较明显的抑制作用。基因组信息显示,181-7携带一个环状的质粒,含有3 826个开放阅读框,含有涉及抗真菌、抗逆、诱导植物抗性和促进植物生长等特性的相关基因。AntiSMASH的分析显示,181-7含有地衣杆菌素(lichenysin)、丰原素(fengycin)、菌溶素(bacilysin)、细菌素(bacteriocin)以及噬铁素等抑菌活性代谢产物。温室的初步试验结果显示,在感病水稻品种‘原丰早'上, 181-7对Xoc在水稻叶片上引起的水渍症状具有明显的抑制作用。这表明, B. altitudinis 181-7具有防治水稻条斑病的潜力。这些研究为水稻条斑病的生物防治提供了新的微生物资源,也为后续生防机理的探究奠定了理论基础。 相似文献
12.
水稻转录因子OsBTF3对不同病原菌和信号分子的基因表达反应 总被引：5，自引：0，他引：5
转录因子基因OsBTF3在水稻品种日本晴悬浮细胞中受白叶枯病菌(Xanthomonas oryzae pv.oryzae,Xoo)诱导表达。为了阐明OsBTF3在水稻叶组织中的表达特征,本研究利用RT-Q-PCR技术,对经3种亲和性病原菌[水稻白叶枯病菌(Xoo)、水稻条斑病菌(Xooc)和稻瘟病菌(Mg)]接种和4种信号分子[脱落酸(ABA)、水杨酸(SA)、茉莉酸甲酯(MeJA)、乙烯(ETH)]诱导处理的水稻叶片中OsBTF3的转录本进行了定量分析。结果表明,OsBTF3对Xoo、Xooc和Mg侵染的基因表达反应均显著地受到诱导,但反应速度和强度略有差异。而4种信号分子对OsBTF3表达的诱导作用差异较大,ABA诱导活性最强,MeJA和ETH次之,SA诱导作用不显著。因此,OsBTF3基因表达不仅具有病原菌Xoo、Xooc和Mg的诱导性,而且也具有信号分子MeJA、ETH和ABA的应答性。 相似文献
13.
14.
杂交稻对白叶枯病的诱导抗性与细胞内防御酶系统关系的初步研究 总被引：52，自引：2，他引：52
在杂交稻幼苗二叶期用水稻白叶枯病弱毒菌株75-1进行诱导处理,至三叶期接种水稻白叶枯病强毒菌株76-25。结果表明:杂交稻感染白叶枯病后,苯丙氨酸解氨酶(PAL)和过氧化物酶(POX)活性升高;超氧物歧化酶(SOD)活性下降,膜脂过氧化产物丙二醛(MDA)含量增加;并且经诱导处理的变化幅度大于未经诱导处理的,抗病组合威优6号的变幅又大于感病组合汕优63。说明杂交稻抗白叶枯病及其诱导抗性与活性氧伤害及细胞内防御酶系有关。 相似文献
15.
水稻白叶枯病菌鸡卵黄抗体的制备及其初步应用 总被引：4，自引：0，他引：4
通过免疫产蛋母鸡制备了针对水稻白叶枯病菌菌株ZJ-173的卵黄抗体(IgY),比较了一种中草药佐剂和福氏佐剂对抗体产生和效价的影响。结果表明:与福氏佐剂相比,中草药佐剂对免疫母鸡的生活力和产蛋影响较小,母鸡恢复产蛋较早(免疫后7天)。卵黄中抗体出现后,两种佐剂处理的抗体都能在抗体出现后15天达到较高效价,并维持较高效价达2个月以上。卵黄抗体经PEG方法提纯后可得到比较纯净的IgY。提纯的IgY蛋白含量平均为11.843mg/ml,双扩散效价为1:128~512。将卵黄抗体IgY作为包被抗体用于异动物抗体双夹心ELISA可有效地检测水稻病叶病种上的白叶枯病菌,其检测灵敏度为104cfu/ml。 相似文献
16.
本试验采用平板溶菌法,测定了新抗生素B—3543对水稻白叶枯病菌的溶菌作用,结果表明其生产菌的分生孢子、菌丝块及抗生素对不同菌系不同菌龄的水稻白叶枯病菌均有很强的溶菌作用,所产生的溶菌圈在一定时间内不断扩大.孢子法所测溶菌圈到14天,直径可达23—35mm;菌块法所测溶菌圈到7天,直径可达30—34.9mm;管碟法所测溶菌圈到4天,直径可达32—34.7mm;纸片法所测溶菌圈到3天,直径可达16.3mm。在此基础上又采用透射电镜对溶菌过程作了显微观察,从细胞形态学角度研究了溶菌作用方式.试验结果表明该素是使细菌细胞壁破裂而导致溶菌,溶菌过程为:①原生质凝结.②细胞壁破裂和原生质外溢。③细胞解体。 相似文献
17.
为探讨大蒜根系分泌物对烟草青枯病菌的抑菌活性,采用抑菌圈法和盆栽试验研究了大蒜根系分泌物及其主要成分对烟草青枯病的影响。结果表明：大蒜根系分泌物浓度为1 g/mL时,对烟草青枯病菌抑制效果最好,其抑菌率为53.67%。大蒜根系分泌物4种成分的抑菌效果由强到弱依次为：2,6-二异丙基苯酚＞二烯丙基二硫＞2,6-二叔丁基对甲酚＞邻苯二甲酸二丁酯。其中,2,6-二异丙基酚对烟草青枯病菌的抑制作用最强,在1和5 mmol/L时的抑菌率分别为99.66%和100.00%;在盆栽试验中也具有较好的防治效果,接种后7 d和14 d后,其防效分别为34.75%和31.35%。因此,大蒜根系分泌物及其成分均对烟草青枯病有明显的抑制作用。本研究揭示了大蒜作为轮作或间作作物对烟草青枯病的防控机理,以及大蒜根系分泌物和2,6-二异丙基酚作为烟草青枯病防治剂的潜力。 相似文献
18.
本研究从梨树根际土壤分离筛选到1株生防细菌ST15,其对水稻黄单胞菌Xanthomonas oryzae具有较强拮抗活性,拮抗圈直径1.50～3.97 cm。基于菌落菌体形态、生理生化特征、16S rDNA和gyrB基因序列,该菌株被鉴定为高地芽胞杆菌Bacillus altitudinis。ST15的无菌发酵滤液对水稻黄单胞菌也具有较强拮抗活性,其拮抗活性分别是1 mg/mL噻唑锌溶液的1.54～1.64倍和10 μg/mL噻霉酮溶液的1.32～1.52倍;同时,研究发现ST15产生的次生代谢抗菌物质对高温、蛋白酶、酸碱（pH 3.0～11.0）及紫外光处理均表现较好稳定性。另外,研究发现ST15可显著促进水稻根系生长（P＜0.01）,对3种常用化学杀细菌剂耐受性较强。田间试验表明,每次喷施ST15生防菌剂15 L/hm2,连续施用两次,其对水稻细菌性条斑病的防效为（63.51±3.28）%,与化学药剂3%噻霉酮悬浮剂的防效相近。综上,高地芽胞杆菌ST15是一株新的生防资源,在防治水稻细菌性条斑病和白叶枯病上具有良好的应用开发前景。 相似文献
19.
贝莱斯芽胞杆菌Bacillus velezensis HN-2为本实验室从土壤中分离得到的一株生防菌，本文研究了菌株HN-2发酵上清液活性成分的最优提取方式、抑菌效果及其活性成分的稳定性。结果表明，通过不同方式提取的菌株HN-2发酵上清液活性成分对3种黄单胞菌均有良好的抑菌活性。其中正丁醇提取物对水稻细菌性条斑病菌Xanthomonas oryzae pv. oryzicola的抑菌效果最好，抑菌圈大小为（41.57±0.33）mm；并且在10 mg/mL浓度下，贝莱斯芽胞杆菌HN-2正丁醇提取物比杆菌肽、春雷霉素和叶枯唑具有更好的抑菌效果。稳定性试验结果表明，贝莱斯芽胞杆菌HN-2正丁醇提取物对pH有较宽的适应范围（pH 1.0～9.0），且在紫外线及高温等环境下仍具有较好的稳定性。综上所述，贝莱斯芽胞杆菌HN-2正丁醇提取物具有开发成为生物源农药的潜力。 相似文献