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991.
E. J. Cother D. H. Noble R. J. Van De Ven V. Lanoiselet G. Ash N. Vuthy P. Visarto B. Stodart 《Plant pathology》2010,59(5):944-953
A study of rice diseases in Cambodia from 2005 to 2007 showed widespread occurrence of diseases caused by Acidovorax avenae subsp. avenae, Burkholderia gladioli, B. cepacia and Pantoea ananatis. This is the first report of these pathogens in Cambodia. Additionally, a pseudomonad causing a widespread disease similar to sheath brown rot (caused by Pseudomonas fuscovaginae) was isolated. The studied strains were pathogenic to rice cvs Sen Pidau and IR 66, producing similar, though slightly less severe, symptoms to those observed in the field. Based on comparative 16S rDNA gene sequence analysis, combined with cell wall fatty acid analysis and metabolic profiles, the isolated strains were allocated to the genus Pseudomonas. The novel species were differentiated from Pseudomonas fuscovaginae and P. putida by their inability to metabolize d ‐fructose, d ‐galactose, d ‐galactonic acid lactone, d ‐galacturonic acid, d ‐glucosaminic acid, d ‐glucuronic acid, p‐hydroxy phenylacetic acid, d ‐saccharic acid and urocanic acid. The major fatty acids were C16:0, summed feature 3 (C16:1ω7c and C16:1ω6c) and summed feature 8 (C18:1ω7c), representing 80% of the total. Partial 16S rRNA gene sequences (1460 bp) were identical, except for two nucleotide changes amongst the six strains. Alignment of the causal strains within type‐culture databases revealed similarities of 99·7% with Pseudomonas parafulva AJ 2129T, 99·2% with P. fulva IAM 1592T, 98·9% with P. plecoglossicidia FPC 951T, and 98·1% with P. fuscovaginae MAFF 301177T. On the basis of data from this polyphasic study, it is proposed that the unknown strains isolated from rice represent a novel species of the genus Pseudomonas. 相似文献
992.
M. Tigano K. De Siqueira P. Castagnone‐Sereno K. Mulet P. Queiroz M. Dos Santos C. Teixeira M. Almeida J. Silva R. Carneiro 《Plant pathology》2010,59(6):1054-1061
The objectives of this work were to evaluate the genetic variability of Meloidogyne enterolobii by molecular markers, and develop species‐specific molecular markers for application in detection. Sixteen M. enterolobii isolates from different geographical regions (Brazil and other countries) and hosts were used in this study. The identification and purification of the populations were carried out based on isoenzyme phenotype. The DNA amplification of the intergenic region (IGS) of the rDNA and of the region between the cytochrome oxidase subunit II (COII) and 16S rRNA genes (mtDNA) produced specific fragments of the expected size for this nematode, i.e. 780 and 705 bp, respectively. Intraspecific variability among the isolates was evaluated with three different neutral molecular markers: AFLP, ISSR and RAPD. The results showed a low level of diversity among the isolates tested, indicating that M. enterolobii is a genetically homogeneous root‐knot nematode species. The RAPD method allowed the identification of a species‐specific RAPD fragment for M. enterolobii. This fragment was cloned and sequenced, and from the sequence obtained, a set of primers was designed and tested. The amplification of a 520‐bp‐long fragment occurred only for the 16 isolates of M. enterolobii and not for the 10 other Meloidogyne species tested. In addition, positive detection was achieved in a single individual female, egg‐mass and second stage juvenile of this nematode. This SCAR species‐specific marker for M. enterolobii represents a new molecular tool to be used in the detection of this nematode from field samples and as a routine diagnostic test for quarantine devices . 相似文献
993.
Felix S. Mwangala Leonard P. Sarna Terry D. Galloway G. R. Barrie Webster 《Pest management science》1993,39(3):179-184
Fenvalerate and permethrin residues on hair of groups of cattle that received either two tags per adult animal or one tag for every other adult animal were determined using gas chromatography over a three-month period in 1987 and 1988. Cattle with two tags had consistently higher residues than cattle with one tag. This difference was statistically significant (P < 0.05) in the first month for residues on the head and in the first two weeks for residues from the body in 1987. Residues on cattle with one tag and without a tag in the same herd were similar (P > 0.05) on each sampling day on all regions. Residues on the hair from the head of cattle with two tags were greater than on the body and rump (P < 0.05) during the first 28 days. Residues found on hair on days 14 and 84 following tag application declined by 80–86% on the head, 73–78% on the body, and 36–86% on the rump. Isomeric compositions of fenvalerate (range 51–61% SR, RS: 39–49% SS, RR) and permethrin (range 61–67% trans: 33–39% cis) were consistent during the study. Rainfall reduced residues on hair. 相似文献
994.
995.
996.
Human acid phosphatase in somatic cell hybrids 总被引:3,自引:0,他引:3
The human enzyme, lysosomal acid phosphatase ACP2, is expressed in nan-rodent somatic cell hybrids as a dimeric molecule. The human-rodent heteropolymer, as well as the human and rodent homopolymer, is associated with lysosomes in these cells. The genes specifying lysosomal acid phosphatase ACP(2) and LDH A are syntenic. 相似文献
997.
998.
999.
Emerson P 《Science (New York, N.Y.)》1900,11(284):911-912
1000.
Avoidance sessions as aversive events 总被引:1,自引:0,他引:1
P N Hineline 《Science (New York, N.Y.)》1972,176(33):430-432
Rats living continuously in conditioning chambers were permitted to work for food before and after their daily avoidance sessions. The avoidance procedure disrupted this responding reinforced by food, a result that indicates conditioned suppression on a time scale much greater than that previously studied in nonhuman animals. 相似文献