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81.
The aim of this research was to confirm the efficacy of the yeast antagonist Candida sake CPA‐1 in suppressing botrytis bunch rot development, in an organic vineyard under Mediterranean conditions for two seasons, and compare its performance with that of two biologically based products currently registered for botrytis bunch rot control in New Zealand. In 2009, treatments applied were: commercial formulations of Ulocladium oudemansii (BOTRY‐Zen®) and chitosan (ARMOUR‐Zen®), C. sake CPA‐1 combined with the fatty acid‐based additive Fungicover® and combinations of these products. All treatments were applied six times between early flowering and harvest and compared with an unsprayed control. In 2010, the treatments focused on C. sake and Fungicover and the number of applications was reduced from six to four. The population dynamics of U. oudemansii and C. sake were measured and wine quality tests were carried out in both seasons. Disease control achieved by C. sake treatments in 2009 were comparable to those achieved by BOTRY‐Zen and ARMOUR‐Zen. Applications of C. sake plus Fungicover between flowering and harvest significantly (< 0·05) reduced botrytis bunch rot incidence and severity by 64% and 90%, respectively, compared with the untreated control in 2009, and by 67% and 89%, respectively, in 2010. Treatments did not adversely affect wine quality parameters after treated grapes were processed. Candida sake consistently provided effective control of botrytis bunch rot in grapes under different meteorological and disease pressure conditions, thereby improving its potential for future commercial applications.  相似文献   
82.
Phytophthora branch canker, caused by Phytophthora citrophthora, has been an increasing problem in clementine (Citrus reticulata) production in Spain during last years. The disease was particularly severe in the new citrus-growing areas of the southwestern coastal areas in Huelva Province. Recent studies revealed that disease emergence was not related to either genetic drift or host specificity changes in P. citrophthora population. Therefore, the possible association of agronomic factors with the disease was investigated. A total of 110 orchards were selected arbitrarily from the main citrus-growing areas in Huelva Province. The presence of branch cankers together with agronomic factors including soils, cultivars, rootstocks, irrigation, pruning, techniques to improve fruit production, fungicide treatments, presence of brown rot of fruit and frost damage were recorded. Logistic regression analysis was used to detect correlations between the agronomic factors studied and disease prevalence. Phytophthora branch canker was significantly associated with mature clementine orchards. Sweet orange and hybrid cultivars as well as young clementine orchards were less affected by the disease. Although disease was less frequent in Salorthid soils, alternative high resolution procedures are required to draw conclusions about the effect of soil properties on disease prevalence. As in other Phytophthora-induced diseases, soil flooding during the rainy season was correlated positively with the prevalence of branch cankers. Improving fruit production by branch scoring showed a strong positive correlation with Phytophthora branch canker. This is the first time that girdling has been associated with Phytophthora disease epidemics on a fruit tree crop, but further research is needed to determine the cause of this relationship. Cultural practices including pruning, regulated deficit irrigation, additional phosphonate sprays, and abiotic and disease factors such as frost damage and presence of brown rot of fruit were not significantly correlated with disease prevalence.  相似文献   
83.
84.
Journal of Plant Diseases and Protection - Assessments were carried out to evaluate disease susceptibility in two local and three internationally recognised plum cultivars...  相似文献   
85.
86.
In this paper we report on an outbreak of reovirus, herpesvirus (Pacheco disease), and/or mycosis infection (Aspergillus spp. and Zygomyces spp.) affecting a batch of young African grey parrots (Psittacus erithacus), with 80% morbidity and 30% mortality. Study material was taken from five birds (four dead and one euthanatized) with a range of clinical symptoms (depression, diarrhea, respiratory symptoms). Diagnosis was confirmed by immunohistochemical detection of avian reovirus, electron microscopy, and virus isolation. Viral antigen of reovirus was detected mainly in large mononuclear cells in the bursa of Fabricius and the spleen, pancreas epithelial cells, and circulating cells; lymphoid organs displayed the largest number of immunopositive cells and severe lymphocyte depletion. Bacteriologic study was negative. Reovirus infection was common in all birds studied, whereas Pacheco disease and mycosis were found in only some, suggesting that reovirus could be the initial cause triggering the outbreak and facilitating infection by other agents and their swift spread through the batch.  相似文献   
87.
The aims of the present study were to determine whether salsolinol (SAL), a dopamine-related compound, is present in the bovine posterior pituitary (PP) gland, and to clarify the effect of SAL on the secretion of prolactin (PRL) in ruminants. SAL was detected in extract of bovine PP gland using high-pressure liquid chromatography with electrochemical detection (HPLC-EC). A single intravenous (i.v.) injection of SAL (5 and 10mg/kg body weight) significantly and dose-dependently stimulated the release of PRL in goats (P<0.05). Plasma PRL levels reached a peak 10min after the injection, then gradually returned to basal values in 60-80min. The PRL-releasing pattern was similar to that in response to sulpiride (a dopamine receptor antagonist). The intracerebroventricular (i.c.v.) injection of 1mg of SAL had no significant effect on the release of PRL in calves, however, 5mg significantly stimulated the release (P<0.05) with peak values reached 30-40min after the injection. Moreover, SAL significantly stimulated the release of PRL from cultured bovine anterior pituitary cells at doses of 10(-6) and 10(-5)M, compared to control cells (P<0.05). Taken together, our data clearly show that SAL is present in extract of the PP gland of ruminants, and has PRL-releasing activity both in vivo and in vitro. Therefore, this endogenous compound is a strong candidate for the factor having PRL-releasing activity that has been previously detected in extract of the bovine PP gland.  相似文献   
88.
The objective of the study was to evaluate an efficacy of sows vaccination protocols in the herd with serious problems affecting efficacy of reproduction. The study was performed in a large pig herd with about 1200 sows. Before vaccination against PCV2, farrowing rate in this farm was about 65%. Sows, boar and replacement gilts were immunized using Circovac vaccine (Merial, France) according to producer's recommendations. Parameters of production were analyzed since 2007 until 2010 in selected batches of sows inseminated at the same weeks of the year (17th, 18th, 19th and 20th) to eliminate seasonal variability. In total, 940 sows were subjected to the study. No significant changes in management during these years were introduced. The applied protocol of sow herd long-term vaccination proved to be very efficient. All measured production parameters: reproduction rate, number of piglets born alive, birth weight of piglets and number of piglets weaned per a litter improved after implementation of immunization program. Moreover, further improvement was observed with vaccination in the following reproduction cycles. The most spectacular effect of vaccination regarded average farrowing rate that increased from 64.76% in control group to 86.93% after basic vaccination. Two years after implementation of vaccination program this parameter reached 93.6%. Number of piglets weaned per sow per a litter improved from 10.31 to 11.74 after one year of vaccination and remained relatively stable through the following year. Simultaneously, the percentage of newborn piglets with birth weight < 1 kg decreased significantly (p < 0.05). To summarize, vaccination against PCV2 influenced positively the insemination rate, number of piglets born alive and weaned per litter as well as birth body weight and percentage of piglets weighing < 1 kg.  相似文献   
89.
1. Eggs from wild and captive populations of Greater Rhea (Rhea americana) were studied to determine their physical and chemical characteristics. 2. Significant differences were found among populations in almost all chemical parameters studied, whereas within physical parameters only shell weight (as a proportion of the entire egg) and density showed differences. 3. Eggs from wild populations had the highest protein and linolenic acid and the lowest total lipid contents, while cholesterol levels of these eggs and of those from the largest captive area were the lowest.  相似文献   
90.
In food industry, roselle beverages and their subproducts could be functional ingredients since they are an excellent source of bioactive compounds with improved performance due to their important anthocyanins content. The aim of this study was to analyze anthocyanin content and antioxidant properties of aqueous infusions elaborated with color contrasting Hibiscus materials and design a mathematical model in order to predict color-composition relationship. Color measurements of beverages from roselle (Negra, Sudan and Rosa) were made by transmission spectrophotometry, anthocyanins quantification was determined by HPLC, and antioxidant potential was evaluated by in vitro methods (ABTS and FRAP assays). Beverages prepared with particle size minor of 250 μm presented until 4- and 2- times more anthocyanins content and antioxidant capacity respectively, in comparison to beverages prepared with powders with particle size major of 750 μm. Positive correlations among pigments composition and color parameters were found (p?<?0.05), showing that anthocyanins content, antioxidant capacity, C*ab and hab values increased in relation with the smallest particle size of flours. Also, mathematical models were stablished to predict anthocyanin content (r?≥?0.97) and antioxidant capacity (r?≥?0.89) from color data; we propose equations for quick estimation of the antioxidant capacity in the Hibiscus beverages with high anthocyanin content. The obtained models could be an important tool to be used in food industry for pigment characterization or functional compounds with potential health benefits.  相似文献   
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