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991.
BACKGROUND: The possibility of improving the efficacy of various insecticides for codling moth, Cydia pomonella (L.), by the addition of a microencapsulated formulation of pear ester, ethyl (2E, 4Z)‐2,4‐decadienoate (PE‐MEC, 5% AI), was evaluated in field trials in apple from 2005 to 2009. RESULTS: The addition of PE‐MEC (<3.0 g AI ha?1) significantly lowered fruit injury with low rates of organophosphate and neonicotinoid insecticides. The addition of PE‐MEC (1.48 g AI ha?1) to maximum label rates of insecticides with moderate activity for codling moth, such as ebamectin benzoate, spinosad and methoxyfenozide, significantly improved their effectiveness. However, PE‐MEC did not consistently improve the activity of maximum label rates of either rynaxypyr or spinetoram. The addition of PE‐MEC with seasonal spray programs of acetamiprid and azinphos‐methyl in combination with the use of sex pheromones for mating disruption provided the most effective control. CONCLUSION: The addition of PE‐MEC can improve the effectiveness of some insecticides for codling moth in apple. Insecticides active via dermal toxicity are more strongly improved by the addition of PE‐MEC. Season‐long use of PE‐MEC can also augment the effectiveness of mating disruption. Adding PE‐MEC to variable integrated management programs for C. pomonella should be further investigated. Published 2012 by John Wiley & Sons, Ltd. 相似文献
992.
Larson G Dobney K Albarella U Fang M Matisoo-Smith E Robins J Lowden S Finlayson H Brand T Willerslev E Rowley-Conwy P Andersson L Cooper A 《Science (New York, N.Y.)》2005,307(5715):1618-1621
Mitochondrial DNA (mtDNA) sequences from 686 wild and domestic pig specimens place the origin of wild boar in island Southeast Asia (ISEA), where they dispersed across Eurasia. Previous morphological and genetic evidence suggested pig domestication took place in a limited number of locations (principally the Near East and Far East). In contrast, new genetic data reveal multiple centers of domestication across Eurasia and that European, rather than Near Eastern, wild boar are the principal source of modern European domestic pigs. 相似文献
993.
Raksha Bhoora Linda Franssen Marinda C. Oosthuizen Alan J. Guthrie Erich Zweygarth Barend L. Penzhorn Frans Jongejan Nicola E. Collins 《Veterinary parasitology》2009
A molecular epidemiological survey of the protozoal parasites that cause equine piroplasmosis was conducted using samples collected from horses and zebra from different geographical locations in South Africa. A total of 488 samples were tested for the presence of Theileria equi and/or Babesia caballi using the reverse line blot hybridization assay. Ten percent of the samples hybridized to the Theileria/Babesia genus-specific probe and not to the B. caballi or T. equi species-specific probes, suggesting the presence of a novel species or genotype. The small subunit of rRNA gene (18S; ∼1600 bp) was amplified and sequenced from 33 of these 488 samples. Sequences were compared with published sequences from the public sequence databases. Twelve distinct T. equi and six B. caballi 18S rRNA sequences were identified. Alignments demonstrated extensive sequence variation in the V4 hypervariable region of the 18S rRNA gene within T. equi. Sequence variation was also found in B. caballi 18S rRNA genes, although there was less variation than observed for T. equi. Phylogenetic analysis based on 18S rRNA gene sequences revealed three T. equi clades and two B. caballi clades in South Africa. The extent of sequence heterogeneity detected within T. equi and B. caballi 18S rRNA genes was unexpected since concerted evolution is thought to maintain homogeneity within repeated gene families, including rRNA genes, in eukaryotes. The findings reported here show that careful examination of variants of the 18S rRNA gene of T. equi and B. caballi is required prior to the development of molecular diagnostic tests to detect these parasites in horses. Species-specific probes must be in designed in regions of the gene that are both conserved within and unique to each species. 相似文献
994.
To understand the relative dietary value of forage fish as prey in the Bering Sea and Gulf of Alaska, whole organisms of 13 species were analysed for proximate composition (protein, oil, ash and moisture content). Eulachon ( Thaleichthys pacificus ) were high in oil (total lipid) (16.8% to 21.4%) and low in moisture (64.6% to 70.8%). Oil in capelin ( Mallotus villosus ) ranged from 2.1% to 14.0%. Juveniles of walleye pollock ( Theragra chalcogramma ), Atka mackerel ( Pleurogrammus monopterygius ), Pacific herring ( Clupea pallasii ), and prowfish ( Zaprora silenus ) had low oil contents (< 1.8%) and high moisture contents (> 80.3%). Rankings of median proximate values illustrate the similarities. Surf smelt ( Hypomesus pretiosus ), rainbow smelt ( Osmerus mordax ), pricklebacks ( Lumpenus spp.), Atka mackerel, Pacific sand lance ( Ammodytes hexapterus ) and Pacific sandfish ( Trichodon trichodon ) ranked high in median protein content (> 15.4%). Median ash content for all species ranged from 0.6% to 3.3%. Total wet mass caloric content (kcal g–1 ) was calculated for the four main species and a linear model was developed for caloric content as a function of moisture. The linear models (caloric content = b0 + b1 × moisture) were Pacific sand lance and Pacific sandfish (b0 = 7.82, b1 = – 0.09); eulachon (b0 = 7.97, b1 = – 0.08); and capelin (b0 = 9.70, b1 = – 0.11). 相似文献
995.
Taylor Alan H. Airey-Lauvaux Catherine Estes Becky Harris Lucas Skinner Carl N. 《Landscape Ecology》2020,35(12):2777-2790
Landscape Ecology - Spatial patterns of fire severity are influenced by fire-vegetation patch dynamics and topography. Since the late nineteenth century, fire exclusion has increased fuels and... 相似文献
996.
Anna C. DILGER Michael E. SPURLOCK Alan L. GRANT David E. GERRARD 《Animal Science Journal》2010,81(5):586-593
Our objective was to determine sensitivity of myostatin null (MN) mice to obesity induction by dietary or genetic means. To induce dietary obesity, 3‐week‐old wild type (WT) and MN mice were fed diets with 60% calories (HF) or 10% calories from fat (LF) for 4 weeks. MN mice did gain body fat on the HF diet but to a lesser extent than WT mice. Body weight and fat content was similar in MN mice fed HF and LF diets. To induce genetic obesity, the MN mutation was incorporated into leptin db/db (DB) mice generating mice homozygous for each mutation (MNDB). Nine‐week‐old MNDB mice were obese, similar to DB mice. Body weight, body fat content, fat pad weight and adipocyte size were all increased in MNDB mice compared to MN and WT mice and were quite similar to DB mice. However, fasting blood glucose, an indicator of insulin resistance and diabetes, was reduced in MNDB mice compared to DB mice. These results indicate that MN mice gain less body fat than WT on a HF diet, but the MN mutation does not alter fat accumulation caused by DB mutation. Thus, MN mice are not always resistant to obesity development. 相似文献
997.
Everett Hansen Paul Reeser Wendy Sutton Alan Kanaskie Sarah Navarro Ellen M. Goheen 《Forest Pathology》2019,49(4)
Phytophthora ramorum, cause of sudden oak death, has been distributed widely across the United States in horticultural situations, but is not established in forests outside of California and Oregon. Here, it has triggered widespread concern and, especially in Oregon, an intensive disease management programme. Now, we provide the first systematic evaluation of the efficacy of that effort. This paper evaluates four measures of the efficacy of Sudden Oak Death (SOD) local eradication treatments: inoculum availability; inoculum from tree species other than tanoak; disease spread from treated areas; and cumulative infested area with and without treatment. We conclude that local treatments demonstrably reduce local inoculum levels. Eradication of SOD from infested sites is difficult but not impossible. The disease usually does not persist after cutting infected trees but spread on the landscape continues because the pathogen may be present on undetected new infections for a year or two before whole tree symptoms are visible. This limits early detection and coupled with delays in completing eradication treatments, prolongs the chances for long‐distance aerial dispersal. 相似文献
998.
999.
Daniela Portz Eckhard Koch Alan J. Slusarenko 《European journal of plant pathology / European Foundation for Plant Pathology》2008,122(1):197-206
The volatile antimicrobial substance allicin (diallylthiosulphinate) is produced in garlic when the tissues are damaged and
the substrate allicin (S-allyl-l-cysteine sulphoxide) mixes with the enzyme alliin-lyase (E.C.4.4.1.4). Allicin undergoes thiol-disulphide exchange reactions
with free thiol groups in proteins and it is thought that this is the basis of its antimicrobial action. At 50 μg ml-1, allicin in garlic juice inhibited the germination of sporangia and cysts and subsequent germ tube growth by Phytophthora infestans both in vitro and in vivo on the leaf surface. Disease severity in P. infestans-infected tomato seedlings was also reduced by spraying leaves with garlic juice containing allicin over the range tested
(55–110 μg ml−1) with an effectiveness ranging from approximately 45–100%. Similarly, in growth room experiments at concentrations from 50–1,000 μg
ml−1, allicin in garlic juice reduced the severity of cucumber downy mildew caused by Pseudoperonospora cubensis by approximately 50–100%. These results suggest a potential for developing preparations from garlic for use in specialised
aspects of organic farming, e.g. for reducing pathogen inoculum potential and perhaps for use under glass in horticulture. 相似文献
1000.