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991.
S. Stankovic J. Levic T. Petrovic A. Logrieco A. Moretti 《European journal of plant pathology / European Foundation for Plant Pathology》2007,118(2):165-172
Fusarium proliferatum can occur on a wide range of economically important vegetable plants but its role in disease is not always well established.
In 2000 and 2001, from forty-one field samples of wilting onion and garlic plants in Serbia, F. proliferatum as the predominant fungal species was isolated from root and bulbs. Seventy isolates were firstly characterized for their
sexual fertility and were shown to be mostly members of Gibberella intermedia (sixty-seven of seventy isolates, the remaining three isolates were unfertile), the sexual stage of F. proliferatum (syn. mating population D of G. fujikuroi complex). A selected set of eleven F. proliferatum isolates from both hosts were also tested for their pathogenicity and toxigenicity. Although onion and garlic plants were
susceptible to all isolates, onion plants showed a significantly higher disease severity index. Six of the eleven isolates
of F. proliferatum produced fumonisin B1 from 25 to 3000 μg g−1, and beauvericin from 400 to 550 μg g−1; ten isolates produced fusaric acid from 80 to 950 μg g−1 and moniliformin from 50 to 520 μg g−1. Finally, all isolates produced fusaproliferin up to 400 μg g−1. These results confirm F. proliferatum as an important pathogen of garlic and onion in Europe and that there is a potential mycotoxin accumulation risk in contaminated
plants of both garlic and onion. 相似文献
992.
993.
玫茄1号的母本是从台湾紫长茄中选育出的自交系21-3,父本是从福建地方品种红茄中选育出的自交系21-4,其杂种一代表现早熟,比对照闽茄1号早收7d(天),果长30~33cm,稍弯,果径4cm,单果重180g,果皮鲜紫色,果肉乳白色,肉质细嫩,商品性好。一般每公顷产30~45t,比对照增产19.5%。该品种已在闽、浙、赣、粤等省推广,种植面积达3200hm2。 相似文献
994.
995.
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997.
乌兰布和荒漠人工绿洲小气候效应研究 总被引:7,自引:0,他引:7
通过对乌兰布和荒漠东北边缘人工绿洲内和荒漠对照区各小气候因子连续12年的同步观察,采用模糊综合评判方法,全面定量分析了防护森体系不同时期的小气候效应及变化规律,评价结果表明,绿洲防护要体系对各气象因子有前显的影响,特别是降低风速,抑制蒸发,提高空气湿度等方面尤为突出,综合小气候效应明显,12年间效益值增加了0.746,增长率为31%,绿洲防护林体系对小气候的改善作用各时期不同,从综合效益值来看,初 相似文献
998.
Objective To determine practices for control of louse infestation and blowfly strike in Queensland sheep flocks that are associated with organophosphorous and synthetic pyrethroid residues on wool.
Design Information on residues was obtained from a survey of Queensland wool clips. Information on pesticide use was obtained from a trace-back postal survey. The association between pesticide use and residues was assessed using generalised linear models, controlling for potential confounding by flock location.
Procedure Between 1995 and 1997 Queensland wool clips were randomly sampled. Samples were tested for the presence and amount (mg per kg of greasy wool) of organophosphorous and synthetic pyrethroid pesticides. A questionnaire seeking information on flock characteristics and pesticide use was sent to the manager of each flock from which a wool sample was tested.
Results The median amount of OP and SP residue was 0.8 and 0.25 mg/kg, respectively, and 91 and 95% of wool samples contained < 8 mg/kg of OP and SP residues, respectively. The frequency of OP pesticide use for louse control was significantly (P = 0.005) associated with mean OP residue amount, and the timing of SP use for louse control, in relation to shearing, was significantly (P < 0.001) associated with mean SP residue amount.
Conclusion Most Queensland wool clips have acceptable amounts of residues after the use of OP and SP pesticides, but wool growers can further reduce residues by effectively controlling louse infestation with pesticide applications early after shearing and the use of non-chemical methods of ectoparasite control. 相似文献
Design Information on residues was obtained from a survey of Queensland wool clips. Information on pesticide use was obtained from a trace-back postal survey. The association between pesticide use and residues was assessed using generalised linear models, controlling for potential confounding by flock location.
Procedure Between 1995 and 1997 Queensland wool clips were randomly sampled. Samples were tested for the presence and amount (mg per kg of greasy wool) of organophosphorous and synthetic pyrethroid pesticides. A questionnaire seeking information on flock characteristics and pesticide use was sent to the manager of each flock from which a wool sample was tested.
Results The median amount of OP and SP residue was 0.8 and 0.25 mg/kg, respectively, and 91 and 95% of wool samples contained < 8 mg/kg of OP and SP residues, respectively. The frequency of OP pesticide use for louse control was significantly (P = 0.005) associated with mean OP residue amount, and the timing of SP use for louse control, in relation to shearing, was significantly (P < 0.001) associated with mean SP residue amount.
Conclusion Most Queensland wool clips have acceptable amounts of residues after the use of OP and SP pesticides, but wool growers can further reduce residues by effectively controlling louse infestation with pesticide applications early after shearing and the use of non-chemical methods of ectoparasite control. 相似文献
999.
Objective To characterise the effects of delmadinone acetate on the pituitary-adrenal axis, glucose tolerance and growth hormone concentration in normal male dogs and dogs with benign prostatic hyperplasia.
Design A prospective study involving nine normal male dogs and seven with prostatic hyperplasia.
Procedure Delmadinone acetate was administered to six normal male dogs and seven dogs with benign prostatic hyperplasia at recommended dose rates (1.5 mg/kg subcuta-neously at 0, 1 and 4 weeks). Three normal controls received saline at the same intervals. Blood concentrations of ACTH, cortisol, glucose, insulin and growth hormone were measured over 50 days. Intravenous glucose tolerance and ACTH response tests were performed before and after treatment in the nine normal animals.
Results A substantial suppression of basal and 2 h post-ACTH plasma cortisol secretion was demonstrated after one dose in all dogs given delmadinone acetate. Individual responses after the second and third administration varied between recovery in adrenal responsiveness to continued suppression. Plasma ACTH concentration was also diminished after one treatment. No effects were evident on glucose tolerance or serum growth hormone concentrations.
Conclusion Delmadinone acetate causes adrenal suppression from inhibition of release of ACTH from the pituitary gland. Treated dogs may be at risk of developing signs of glucocorticoid insufficiency if subjected to stressful events during or after therapy. Neither glucose intolerance nor hyper-somatotropism seems likely in male dogs given delmadinone acetate at the recommended dose rate, but the potential for excessive growth hormone secretion in treated bitches remains undetermined. 相似文献
Design A prospective study involving nine normal male dogs and seven with prostatic hyperplasia.
Procedure Delmadinone acetate was administered to six normal male dogs and seven dogs with benign prostatic hyperplasia at recommended dose rates (1.5 mg/kg subcuta-neously at 0, 1 and 4 weeks). Three normal controls received saline at the same intervals. Blood concentrations of ACTH, cortisol, glucose, insulin and growth hormone were measured over 50 days. Intravenous glucose tolerance and ACTH response tests were performed before and after treatment in the nine normal animals.
Results A substantial suppression of basal and 2 h post-ACTH plasma cortisol secretion was demonstrated after one dose in all dogs given delmadinone acetate. Individual responses after the second and third administration varied between recovery in adrenal responsiveness to continued suppression. Plasma ACTH concentration was also diminished after one treatment. No effects were evident on glucose tolerance or serum growth hormone concentrations.
Conclusion Delmadinone acetate causes adrenal suppression from inhibition of release of ACTH from the pituitary gland. Treated dogs may be at risk of developing signs of glucocorticoid insufficiency if subjected to stressful events during or after therapy. Neither glucose intolerance nor hyper-somatotropism seems likely in male dogs given delmadinone acetate at the recommended dose rate, but the potential for excessive growth hormone secretion in treated bitches remains undetermined. 相似文献
1000.
C. HAMBLIN JS SALT SD GRAHAM K. HOPWOOD AM WADE-EVANS 《Australian veterinary journal》1998,76(9):622-629
Objective To study the clinical signs following bluetongue virus serotypes 1 and 3 infection in Poll Dorset sheep.
Design A clinical and pathological study.
Procedure Twenty Poll Dorset sheep were inoculated with bluetongue virus serotypes 1 or 3, each inoculum having a different passage history. The sheep were examined daily and their clinical appearance and rectal temperatures recorded. Heparinised and non-heparinised blood samples were taken at intervals for virological and serological study. Gross pathological findings were recorded for several sheep at necropsy and tissue samples were collected from three sheep for virological studies.
Results All inoculated sheep developed clinical disease. The clinical signs and gross pathological changes varied considerably but were consistent with damage to the vascular endothelial system. There was a decline in the titres of infectious bluetongue virus and of antigen in tissues collected between 7 and 12 days after infection.
Conclusions The severity of disease was related to the speed of onset and duration of pyrexia and not the development or titre of viraemia. Generally, those animals with sensitive mouths, depression, coronitis, recumbency and reluctance to move were the most debilitated. Whole blood was the most reliable source of infectious virus from acutely and chronically infected and convalescent animals. However, tissue samples particularly spleen, collected from dead or killed animals suffering from either peracute or acute forms of disease were most appropriate for the rapid confirmation of a clinical diagnosis. 相似文献
Design A clinical and pathological study.
Procedure Twenty Poll Dorset sheep were inoculated with bluetongue virus serotypes 1 or 3, each inoculum having a different passage history. The sheep were examined daily and their clinical appearance and rectal temperatures recorded. Heparinised and non-heparinised blood samples were taken at intervals for virological and serological study. Gross pathological findings were recorded for several sheep at necropsy and tissue samples were collected from three sheep for virological studies.
Results All inoculated sheep developed clinical disease. The clinical signs and gross pathological changes varied considerably but were consistent with damage to the vascular endothelial system. There was a decline in the titres of infectious bluetongue virus and of antigen in tissues collected between 7 and 12 days after infection.
Conclusions The severity of disease was related to the speed of onset and duration of pyrexia and not the development or titre of viraemia. Generally, those animals with sensitive mouths, depression, coronitis, recumbency and reluctance to move were the most debilitated. Whole blood was the most reliable source of infectious virus from acutely and chronically infected and convalescent animals. However, tissue samples particularly spleen, collected from dead or killed animals suffering from either peracute or acute forms of disease were most appropriate for the rapid confirmation of a clinical diagnosis. 相似文献