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21.
In order to improve the efficiency of the known floral attractant of Epicometis hirta [(E)-anethol and (E)-cinnamyl alcohol in a ratio of 1:1], candidate synergist compounds for field tests were selected through electroantennographic tests using the antennae of female and male E. hirta adult beetles. Among synthetic floral compounds 4-methoxyphenethyl alcohol and methyl salicylate evoked high responses from the antennae and were chosen for further field studies. In trapping tests in Bulgaria, the addition of 4-methoxyphenethyl alcohol to the E. hirta bait in the ratio of 1:1:1, in Hungary in ratios of 1:1:0.3 and 1:1:1 significantly increased catches. The addition of methyl salicylate was without effect in both countries. A high-capacity trap supplied with this ternary attractant could be more efficient for mass trapping purposes of E. hirta in environment-friendly plant protection.  相似文献   
22.
Enteropathogenic Escherichia coli (EPEC) that are known to cause severe diarrhoea in children and young rabbits are well characterized, but there are few reports on the serotypes and intimin (eae) types of EPEC in weaned pigs. Based on detection of the eae gene by PCR and by DNA-hybridisation with LEE specific gene probes, 20 intestinal and 17 faecal eae(+) strains from diarrhoeal (164) and non-diarrhoeal (57) weaned pigs from 13 Hungarian farms, representing 12.8% of diarrhoeal and 14.0% of non-diarrhoeal pigs, were identified. The dominant serotype was O123:H11 (40%) among intestinal, and O108:H9 (23%) among faecal strains. The majority (85%) of the intestinal strains possessed eae-beta and 10% carried eae-gamma gene. In contrast, significantly (p<0.025) fewer faecal strains (53%) harboured the eae-beta gene, and 23% were eae-gamma positive. In vitro adhesion tests of intestinal and faecal eae(+) strains indicated adhesion of 20/37 of the strains to PK15 (porcine kidney) cells while only 3/37 strains adhered to HeLa cells. The ultrastructure of intimate bacterial attachment of representative porcine eae(+) strains to PK15 cells showed no pedestal formation, in contrast to the human EPEC (O127:H5, eae-alpha) strain. In conclusion, the data do not demonstrate a significant role for the eae(+)E. coli in porcine post-weaning diarrhoea, but provide new information on a dominant porcine serotype (O123:H11, eae-beta), and on differences of serotypes and intimin types of porcine eae(+) strains according to their site of isolation. Furthermore there was an indication that the PK15 cell line could be used as a model to study in vitro adherence of eae(+)E. coli of some human and porcine origin.  相似文献   
23.
Five winter wheat cultivars--GK Othalom (HMW-GS composition 2*, 7+8, 5+10), Ukrainka (1, 7+8, 5+10), Palotás (2*, 7+9, 5+10), K?dm?n (2*, 7+8, 5+10), and Csongrád (2*, 7+9, 2+12)--grown in Hungary and harvested in the year 2005 were studied. The biosynthesis of gluten-forming polypeptides was followed starting at the 12th day after anthesis to the 53rd. Fresh kernel weight, moisture, and dry matter content of fresh kernels and gliadin and glutenin contents were determined. Gliadin components, total amounts of HMW and LMW polypeptides, and individual HMW polypeptides were determined using a RP-HPLC technique. Although considerable quantitative differences were observed concerning the content of total protein, gliadin, glutenin, and individual gluten-forming polypeptides, the character of accumulation of protein components--determined on the basis protein mass/kernel--was the same for the all of the cultivars studied and could be presented by a sigmoid curve. Small quantities of the gliadin and glutenin monomers may be detected in early stages of kernel development, but the bulk of these proteins is synthesized in later stages of development. It is generally suggested by specialists that the formation and accumulation of glutenin polymers starts later than the synthesis of monomers. Experimental data presented in this paper confirm this suggestion and show that in the first phase of protein synthesis the monomers are in "free" form; polymeric glutenin is detected only later. HMW glutenin subunits are synthesized synchronously, and quantitatively the polypeptides coded by chromosomes D and B dominate.  相似文献   
24.
Partitioning of contact networks into communities allows groupings of epidemiologically related nodes to be derived, that could inform the design of disease surveillance and control strategies, e.g. contact tracing or design of 'firebreaks' for disease spread. However, these are only of merit if they persist longer than the timescale of interventions. Here, we apply different methods to identify concordance between network partitions across time for two animal trading networks, those of salmon in Scotland (2002-2004) and livestock in Great Britain (2003-2004). Both trading networks are similar in that they moderately agree over time in terms of their community structures, but this concordance is higher--and therefore community structure is more consistent--when only the 'core' network of nodes involved in trading over the whole time series is considered. In neither case was higher agreement found between partitions close together in time. These measures differ in their absolute values unless appropriate standardisation is applied. Once standardised, the measures gave similar values for both network types.  相似文献   
25.
Seasonal changes in testis volume, testosterone (T) productivity (GnRH test) and semen characteristics of Mangalica boars were studied. The biggest testis volume was measured in autumn and the smallest in winter. Significant differences were demonstrated between autumn-winter (P = 0.012) and autumn-spring (P = 0.015) in testis volume. The highest basic T concentration (Tb) was observed in autumn and the lowest in summer. The provoked T concentration (Tincr) was significantly higher in autumn than in spring (P = 0.0007). A strong correlation was observed between T concentrations and testis volume in spring. The highest ejaculate volume was measured in winter while the lowest in autumn. Significant differences were found in semen concentration as well as in the total number of spermatozoa per ejaculate between seasons. The highest number of abnormal sperm cells was observed in spring while the lowest in summer. It can be concluded that the ejaculate of the Mangalica breed tends to be of lower volume and higher sperm concentration as compared to most pig breeds. Seasonal differences could be observed in testicular measurements, testosterone production capacity and sperm morphological features; however, sperm motility remained constantly high during the study.  相似文献   
26.
Carp, 15–25 g in weight, were maintained on diets containing linolenic acid in various concentrations (0.5, 1.0, 3.4 and 11.1 mg/g food) for 4 weeks and the fatty acid composition of liver total lipids as well as that of liver triglycerides and phospholipids was determined. The fish ingesting the diet containing 1.1% linolenate accumulated only negligible amounts of 20:3 ω 9 and exhibited a low ratio of 20:3 ω 9 to 22:6 ω 3 (0.07) in the total lipid. This ratio increased from 0.33 to 2.00 in liver total lipids of fish ingesting 3.4, 1.0 and 0.5 mg linolenic acid in 1 g of food. This effect was more pronounced in the phospholipids. The level of oleic acid in triglycerides was inversely related to the concentration of linolenic acid in the diet. Linoleic acid at a concentration of 13–16 mg/g food was unable to prevent the accumulation of 20:3 ω 9 in the lipids of fish ingesting diets containing a low level of linolenate. The possible effects of dietary linolenate on the fatty acid metabolism of fish are discussed.  相似文献   
27.
The Rx1 and Rx2 are extreme resistance genes, which have been introgressed from different species into potato cultivars and breeding lines. These two genes have a 98% and 96% sequence similarity at the nucleotide as well as at the amino acid level, respectively. Except one extra amino acid in the Rx2 gene, the high variations of the amino acid chain are due to single and double nucleotide variations, which are scattered throughout the coding regions. The high level of sequence similarity makes it complicated to identify these genes and to distinguish them from other highly similar genes, like the Gpa2 or from paralogous sequences by a single polymerase chain reaction (PCR). Here, we report the development of markers for the simple and rapid identification of the Rx1 as well as the Rx2 gene. Further, a multiplex PCR reaction is recommended for the simultaneous detection of both genes in a single reaction. Since these genes reside on different chromosomes, following their inheritance by the multiplex PCR method could help the easy incorporation of both genes into breeding lines. The detection method shown here could be routinely used in marker-assisted selection for Potato virus X extreme resistance and could enhance the effectiveness of potato breeding programs. Besides potato breeding, this method could also be effectively applied to mapping experiments as well as in research studies of resistance.  相似文献   
28.
We selected wheat SSR markers specific to the U and M genomes of Aegilops species. A total of 108 wheat SSR markers were successfully tested on Ae. biuncialis (2n = 4x = 28, UbUbMbMb), on five wheat–Ae. biuncialis addition lines (2Mb, 3Mb, 7Mb, 3Ub and 5Ub) and on a wheat–Ae. geniculata (1Ug, 2Ug, 3Ug, 4Ug, 5Ug, 7Ug, 1Mg, 2Mg, 4Mg, 5Mg, 6Mg and 7Mg) addition series. Among the markers, 86 (79.6%) were amplified in the Ae. biuncialis genome. Compared with wheat, polymorphic bands of various lengths were detected on Ae. biuncialis for 35 (32.4%) of the wheat microsatellite markers. Three of these (8.6%) exhibited specific PCR products on wheat–Ae. biuncialis or wheat–Ae. geniculata addition lines. The primers GWM44 and GDM61 gave specific PCR products on the 2Mb and 3Mb wheat–Ae. biuncialis addition lines, but not on the 2Mg addition line of Ae. geniculata. A specific band was observed on the 7Ug wheat–Ae. geniculata addition line using the BARC184 primer. These three markers specific to the U and M genomes are helpful for the identification of 2Mb, 3Mb and 7Ug chromosome introgressions into wheat.  相似文献   
29.
Bioassay-guided fractionation of the chloroform extract of Centaurea jacea L. afforded the isolation of cirsiliol, apigenin, hispidulin, eupatorin, isokaempferide, axillarin, centaureidin, 6-methoxykaempferol 3-methyl ether, trachelogenin, cnicin, 4'-acetylcnicin and three aliphatic glucose diesters, including the new natural product 1β-isobutanoyl-2-angeloyl-glucose. The structures of the compounds were established on the basis of spectroscopic analyses (UV, MS and NMR). All compounds were isolated for the first time from this species. The compounds were evaluated for their tumour cell growth inhibitory activities on HeLa, MCF-7 and A431 cells. Different types of secondary metabolites (flavonoids, sesquiterpenes) were found to be responsible for the antitumour effects of the extracts; the highest activity was exerted by centaureidin, in addition to moderately active compounds (cirsiliol, isokaempferide, apigenin, hispidulin, cnicin and 4'-acetylcnicin).  相似文献   
30.
Based on analysis of pheromone gland extracts, highly attractive new baits have been developed for three click beetle pests. That for Agriotes brevis is a mixture of geranyl butanoate and (E,E)-farnesyl butanoate, and that for A rufipalpis and A sordidus contains geranyl hexanoate alone. From known data from species populating Russia, optimized bait compositions for species in Central and Western Europe were developed as follows: geranyl octanoate + geranyl butanoate for A lineatus, geranyl isovalerate for A litigiosus, geranyl hexanoate + geranyl octanoate for A obscurus, geranyl butanoate alone for A sputator and (E,E)-farnesyl acetate alone for A ustulatus. Although slight differences were found in gland contents with A litigiosus var laichartingi and fenotypus typicus, nevertheless there were no differences in response to the optimum bait. There were no differences in pheromone composition or response to the optimized bait between the two morphological forms ('black' and 'red') of A ustulatus. As a result of these studies, highly effective pheromone baits are now available for monitoring and population reduction in all important pest click beetle species in Central and Western Europe.  相似文献   
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