Relative importance of seed‐tuber and soilborne inoculum in causing black dot disease of potato     

A. K. Lees  J. L. Brierley  J. A. Stewart  A. J. Hilton  S. J. Wale  P. Gladders  N. J. Bradshaw  J. C. Peters 《Plant pathology》2010,59(4):693-702

Controlled‐environment and field experiments were done to quantify the individual contribution of seed‐tuber and soilborne inoculum of Colletotrichum coccodes in causing black dot disease of potato tubers. Seed‐tuber and soilborne inocula of C. coccodes were quantified using an existing real‐time PCR assay and related to subsequent incidence and severity of disease. In four field trials, a controlled‐environment experiment and through the monitoring of 122 commercial crops, seed‐tuber inoculum was found to be relatively less important than soilborne inoculum in causing black dot, and the level of seed‐tuber inoculum did not significantly affect either the incidence or severity of disease or the percentage of progeny tubers deemed unmarketable. By contrast, soilborne inoculum had the potential to result in high levels of disease and the level of C. coccodes soil infestation (pg DNA g^?1 soil) was found to have a significant effect. At soil infestation levels below 100 pg DNA C. coccodes g^?1 soil, 7% of commercial crops had an incidence of black dot greater than 20%, increasing to 40% and 57% of crops at levels of 100–1000 pg g^?1 and >1000 pg g^?1 soil, respectively. These arbitrary threshold levels for soilborne inoculum related to disease risk are discussed. Interpretation of disease risk based on inoculum levels must, in the future, be informed by agronomic variables and potential control strategies.  相似文献   

Experimental studies of the role of the little raven (Corvus mellori) in surveillance for West Nile virus in Australia     

J Bingham  RA Lunt  DJ Green  KR Davies  V Stevens  FYK Wong 《Australian veterinary journal》2010,88(6):204-210

Objective To study the potential role of an Australian corvid, the little raven (Corvus mellori), in the surveillance for exotic West Nile virus (WNV) in Australia. Method In a series of trials, little ravens were infected with WNV (strain 4132 New York 1999) and Kunjin virus (strain K42886) by the intramuscular route. They were observed for 20 days during which blood and swab samples were taken for virus isolation. Tissue samples were taken from ravens humanely killed during the acute infection period, and at the termination of the trials, for virus isolation, histopathology and immunohistochemistry. Results Ravens infected with WNV became mildly ill, but all recovered and seroconverted. Blood virus titres peaked around 3 to 4 days after inoculation at levels between 10^3.0 to 10^7.5 plaque forming units/mL. Virus or viral antigen was detected in spleen, liver, lung, kidney, intestine, testis and ovary by virus isolation and/or immunohistochemistry. WNV was detected in oral and cloacal swabs from 2 to 7 days post inoculation. The molecular and pathogenic characteristics of the inocula were consistent with them being of high virulence, as expected for this isolate. Ravens infected with Kunjin virus developed viraemia and seroconverted, although they did not develop disease. Conclusions Little ravens do not develop severe disease in response to virulent WNV infection and for this reason may not be important sentinel hosts in the event of an outbreak of WNV, as in North America. However, as they have relatively high viraemias, they may be able to support virus cycles.  相似文献   

Predicting the emergence of the codling moth,Cydia pomonella (Lepidoptera: Tortricidae), on a degree‐day scale in North America     

Vincent P Jones  Richard Hilton  Jay F Brunner  Walt J Bentley  Diane G Alston  Bruce Barrett  Robert A Van Steenwyk  Larry A Hull  James F Walgenbach  William W Coates  Timothy J Smith 《Pest management science》2013,69(12):1393-1398

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Chemical and physical changes in milk protein concentrate (MPC80) powder during storage     

Le TT  Bhandari B  Deeth HC 《Journal of agricultural and food chemistry》2011,59(10):5465-5473

The solubility and chemical changes due to the Maillard reaction were investigated in milk protein concentrate powder containing 80% protein (MPC80) during storage at temperatures and relative humidities in the ranges of 25-40 °C and 44-84%, respectively. The Maillard reaction was studied by measuring furosine (a product of lactosylated protein after digestion with acid) and free hydroxymethylfurfural (HMF) contents by HPLC and L*, a*, b* values with a color-meter. Furosine, free HMF, and browning in MPC80 increased during storage, whereas the solubility decreased. The correlation between the Maillard reaction and solubility loss was explored in modified MPC80 to which glucose was added to enhance the rate of the Maillard reaction. More furosine and brown pigments were observed in the glucose-containing MPC80 than in MPC80 with added lactose. The opposite trend occurred for solubility, suggesting that the Maillard reaction may be a cause of solubility loss in MPC powder.  相似文献   

Expression of cyclooxygenase genes in the jejunum of horses during low-flow ischemia and reperfusion     

Hilton H  Nieto JE  Moore PF  Harmon FA  Naydan DK  Snyder JR 《American journal of veterinary research》2011,72(5):681-686

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Estimation of relationships between mineral concentration and fatty acid composition of longissimus muscle and beef palatability traits     

Garmyn AJ  Hilton GG  Mateescu RG  Morgan JB  Reecy JM  Tait RG  Beitz DC  Duan Q  Schoonmaker JP  Mayes MS  Drewnoski ME  Liu Q  VanOverbeke DL 《Journal of animal science》2011,89(9):2849-2858

The objective of this study was to determine the influence of beef LM nutrient components on beef palatability traits and evaluate the impact of USDA quality grade on beef palatability. Longissimus muscle samples from related Angus cattle (n = 1,737) were obtained and fabricated into steaks for trained sensory panel, Warner-Bratzler shear force (WBSF), lipid oxidation measured by thiobarbituric acid reactive substances (TBARS), fatty acid, and mineral composition analysis. Pearson phenotypic correlations were obtained by the correlation procedure of SAS. Beef palatability data were analyzed by the GLM procedure of SAS with USDA quality grade as the main effect. Specific mineral concentrations did not demonstrate strong correlations with WBSF or sensory traits (r = -0.14 to 0.16). However, minerals appeared to have a stronger relationship with flavor; all minerals evaluated except Ca and Mn were positively correlated (P < 0.05) with beef flavor. Stearic acid (C18:0), C18:2, C20:4, and PUFA were negatively correlated (P < 0.05) with all 3 panelist tenderness traits (r = -0.09 to -0.22) and were positively correlated (P < 0.05) with WBSF (r = 0.09 to 0.15). The MUFA were positively correlated (P < 0.05) with panelist tenderness ratings (r = 0.07 to 0.10) and negatively associated (P < 0.05) with WBSF (r = -0.11). The strongest correlations with juiciness were negative relationships (P < 0.05) with C18:2, C18:3, C20:4, and PUFA (r = -0.08 to -0.20). Correlations with beef flavor were weak, but the strongest was a positive relationship with MUFA (r = 0.13). Quality grade affected (P < 0.05) WBSF, TBARS, and all trained sensory panel traits, except livery/metallic flavor. As quality grade increased, steaks were more tender (P < 0.05), as evidenced by both WBSF and sensory panel tenderness ratings. Prime steaks were rated juiciest (P < 0.05) by panelists, whereas Select and Low Choice were similarly rated below Top Choice for sustained juiciness. Quality grade influenced (P < 0.05) beef flavor, but not in a linear fashion. Although there were significant correlations, these results indicate tenderness, juiciness, and flavor are not strongly influenced by individual nutrient components in beef LM. Furthermore, the positive linear relationships between USDA quality grade and beef palatability traits suggest quality grade is still one of the most valuable tools available to predict beef tenderness.  相似文献   

Testing the resistance to silver scurf in commercial potato cultivars under controlled environmental conditions     

A. J. Hilton  H. E. Stewart  S. L. Linton  M. J. Nicolson  A. K. Lees 《Potato Research》2000,43(3):263-271

Summary Optimum storage conditions to identify resistance to silver scurf among commercially grown potato cultivars were determined in a series of experiments. Inoculation of field-grown tubers with a conidial suspension ofH. solani (concentration 10⁴ conidia per ml of water) and incubation at 15°C with 95% RH for 1 month followed by 2 months at 85% RH produced the greatest differences in disease severity between potato cultivars. Results with glasshouse-grown tubers were comparable with those from field-grown tubers, indicating that the test could be used to identify resistance in wild species of potato and to understand the inheritance of this resistance.  相似文献   

Vegetarian dog foods          下载免费PDF全文

Hilton JW 《The Canadian veterinary journal. La revue veterinaire canadienne》1987,28(8):535-539

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Les antioxydants: rôles, types et nécessités dans les aliments pour animaux de compagnie          下载免费PDF全文

Hilton JW 《The Canadian veterinary journal. La revue veterinaire canadienne》1989,30(10):834-837

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Antioxidants: function, types and necessity of inclusion in pet foods          下载免费PDF全文

Hilton JW 《The Canadian veterinary journal. La revue veterinaire canadienne》1989,30(8):682-684

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