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PCR方法鉴别肉骨粉中的动物成份种类 总被引:9,自引:0,他引:9
为防范疯牛病传入我国,有必要鉴别肉骨粉中动物成份的种类。针对牛、羊、猪和鸡四种动物的特异性核苷酸序列,分别选用和设计了四对特异性引物,用试剂盒提取四种动物的肉骨粉或者处理过的肉组织中的DNA,然后进行PCR扩增,所扩增的目的片断大小分别为271bp、199bp、196bp、148bp,运用PCR技术建立了鉴定这四种动物源性成分的方法。结果分别扩增出四种动物的特异性条带,证明该PCR方法具有很高的特异性和敏感性,而且成本低廉,简便易行,因此可以作为鉴别肉骨粉种类的常规方法。 相似文献
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烟草黑胫病菌(Phytophthora parasitica var. nicotianae)生理小种鉴定技术研究 总被引:1,自引:0,他引:1
在1980-1986年,对烟草黑胫病菌生理小种鉴定技术和方法进行了研究和探讨。结果表明,Nicotiana ncsophil(?),Burley21;Burley37;N.stocktonii是理想的鉴别寄主:整株接种方法优于其他的接种方法;接种物浓度以控制在相同的水平(10~3 ml)为宜。为减小生物测定的差异,所有菌系应一次完成测定。 相似文献
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S.K. Weldon D.A. Mosier K.R. Simons R.C. Craven A.W. Confer 《Veterinary microbiology》1994,40(3-4):283-291
To identify antigens which may be important for stimulating immunity to pneumonic pasteurellosis, a bovine antiserum to whole P. haemolytica was used to screen a recombinant lambda gt11/P. haemolytica expression library. One of the recombinant bacteriophage clones identified with the bovine antiserum, SW20C, expressed a fusion protein which was also recognized by rabbit antiserum to partially purified P. haemolytica culture supernatant and was found to be immunogenic in guinea pigs. The guinea pig antibody recognized a 100 kDa protein in P. haemolytica cell lysates. Sequence analysis of the cloned DNA from SW20C identified a fragment of 1443 bp with a small open reading frame that was contiguous with the lacZ sequence. The 153 bp P. haemolytica-specific open reading frame encoded a polypeptide of approximately 6kDa. Homology searches of Genbank and the EMBL data bases revealed no homology of this open reading frame with any other bacterial sequences including P. haemolytica leukotoxin and Ssa1. Evaluation of sera from calves that were scored either susceptible or resistant to experimental pneumonic pasteurellosis demonstrated a significant (P < 0.001) correlation between the intensity of the antibody response to the SW20C antigen and resistance to disease. 相似文献
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据1981~1983年9个哈密瓜生产基地根颈部病害的病原成份调查表明,哈密瓜疫病的优势种为掘氏疫霉菌(Phytophthora drechsleri Tucker.)。为澄清在新疆掘氏疫霉的寄主范围,1989~1990年用1981年采自鄯善县哈密瓜上分离的单孢(Phy-6)菌株,在温室平均温度25~28℃条件下对5科25种自然根颈感病的栽培作物作接种试验。结果表明,本菌是葫芦科大多数作物的重要致病菌,并可侵染棉花和红花;在有伤口条件下可以侵染南瓜、西葫芦和茄株;对苦瓜、丝瓜,豆科作物的豇豆、四季豆、菊科的向日葵、茄科的蕃茄、辣椒、烟草、马铃薯、蔷薇科草莓(植株)等均不能致病。 相似文献
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After about 25 years of intensive research a substantial moment of information has accumulated on the basic biology of Prostephanus truncatus in stored products. This article reviews the literature on the geographical distribution, biotypes, symbiotic associations, mating and flight behaviour, oviposition, and development on both agricultural and non-agricultural hosts. The current knowledge about the nutritional biology (including the role of symbionts) and host finding behaviour (including the inter-linked roles of plant chemicals and the insect's own pheronones) are highlighted as research areas which deserve future attention. In addition, few studies have been conducted to determine the extent to which the biology of P. truncatus permits it to survive and reproduce in non-agricultural environments. These areas of study should be pursued as possible routes to providing more effective integrated pest managements strategies for the larger grain borer. 相似文献
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To determine the potential of sexual reproduction among host-adapted populations of Phytophthora infestans sensu lato in Ecuador, 13 A1 isolates belonging to clonal lineages US-1, EC-1 and EC-3, and 11 A2 isolates belonging to the clonal lineage EC-2, were paired on agar plates to induce crossing. In the first experiment, six A1 isolates (three US-1, two EC-1 and one EC-3) were each crossed with three A2 isolates (total = 18 crosses). Matings involving isolates of the EC-1 lineage produced more oospores of healthy appearance than did matings with isolates of US-1 or EC-3. In the second experiment, the oospores of 35 crosses (21 EC-1 × EC-2; 10 US-1 × EC-2; four EC-3 × EC-2) were dispersed on water agar to assess oospore germination. Overall, germination percentages were low. Only one cross produced enough progeny for evaluation. Twenty-three single-oospore offspring were isolated and evaluated for mating type; electrophoretic patterns of glucose-6-phosphate isomerase ( Gpi ) and peptidase ( Pep ) alloenzyme loci; mitochondrial DNA haplotype; and genomic DNA fingerprint. Multilocus genotype data indicated that all 23 isolates resulted from meiotic recombination. Four progeny with homothallic phenotype appeared to be unstable heterokaryons. Markers at several loci segregated according to simple Mendelian expectations for a diploid organism, but the ratios of three RFLP loci and the Pep locus were not consistent with Mendelian expectations. All progeny were nonpathogenic on hosts of the parental genotypes. Reduced mating success and reduced pathogenic fitness of progeny appear to be postmating mechanisms of reproductive isolation in populations of P. infestans sensu lato in Ecuador. 相似文献
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Nihal Özder 《Phytoparasitica》2002,30(4):434-436
Nymphal development time and fecundity ofSitobion avenae (F.) (Homoptera: Aphididae) were determined on nine widespread wheat varieties cultivated in Tekirdağ Region in Turkey. Tests
were carried out in controlled environment chambers (25±1°C, 65±5% r.h.; 16:8, L:D). Development time (±S.E.) ranged from
5.75±0.25 to 7.20±0.20 days. Fecundity per female ofS. avenae was found to be the highest (12.87±1.50) on wheat cv. ‘Sana’. In this investigation cvs. ‘MV-17’, ‘Miryana’, ‘Pehlivan’ and
‘Saraybosna’ were particularly resistant againstS. avenae.
http://www.phytoparasitica.org posting July 8, 2002. 相似文献