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Spray Treatment (spray + treatment)
Selected AbstractsProtective, Curative and Eradicant Activity of the Strobilurin Fungicide Azoxystrobin against Cercospora beticola and Erysiphe betaeJOURNAL OF PHYTOPATHOLOGY, Issue 11-12 2003T. Anesiadis Abstract The protective, curative and eradicant activity of the strobilurin fungicide azoxystrobin against Cercospora beticola and Erysiphe betae on sugar beet was determined under growth chamber conditions. Difenoconazole and chlorothalonil were used as standard fungicides against C. beticola, while chlorothalonil was replaced by sulphur against E. betae. Fungicides were applied before (protective treatments) and after (curative treatments) inoculation at 24, 48 and 96 h intervals, respectively. An additional spray treatment was applied after the appearance of the symptoms to evaluate the eradicant activity of the fungicides tested. Applications of azoxystrobin at 16 ,/ml provided 89,94% and 95,97% disease control against C. beticola and E. betae, respectively. Curative treatments of azoxystrobin either at 8 or 16 ,g/ml provided control of Cercospora leaf-spot higher than 90% only when it was applied 24 h after inoculation of the plants. Comparatively, chlorothalonil (100 ,g/ml) provided satisfactory control of C. beticola when applied in protective treatments (83,87% disease control) but showed little activity when applied after the inoculation of the seedlings (45,76% disease control). High control efficacy against E. betae was also obtained by protective applications of sulphur (600 ,g/ml) but the fungicide failed to provide satisfactory disease control, particularly when applied for 48 or 96 h after inoculation of seedlings. Difenoconazole (8 ,g/ml) gave excellent protective and curative activity against both pathogens. Eradicative treatments with azoxystrobin provided high antisporulant activity of 94,96% and 85,93% against C. beticola and E. betae, respectively. Similarly, high antisporulant activity was also provided by difenoconazole, while postsymptom applications of chlorothalonil and sulphur provided significantly lower antisporulant activity against C. beticola and E. betae, respectively. Such results encourage the evaluation of azoxystrobin under field conditions to determine optimal treatment schedules and to select possibly partner fungicides for use in mixtures. [source] Topical treatment with aqueous solutions of rofleponide palmitate and budesonide in a pollen-season model of allergic rhinitisCLINICAL & EXPERIMENTAL ALLERGY, Issue 5 2004C. Ahlström-Emanuelsson Summary Background Rofleponide palmitate is an esterified glucocorticosteroid pro-drug with a promising pre-clinical profile designed to deliver topical airway treatment for allergic rhinitis and asthma in a novel manner. Thus, the rofleponide palmitate pro-drug is designed to provide topical exposure of the mucosa to the inactive lipophilic drug, which would be locally metabolized to the more hydrophilic and readily cleared drug rofleponide. Objective To examine whether rofleponide palmitate affects nasal symptoms and peak inspiratory flow (PIF) in a pollen-season model of allergic rhinitis and to compare any such effects with those of another glucocorticosteroid (i.e., budesonide). Methods During the pollen-free season, 40 patients with strictly seasonal allergic rhinitis received topical nasal spray treatment with an aqueous solution of rofleponide palmitate 400 ,g and an aqueous solution of budesonide 128 ,g once daily for 10 days in a double-blind, placebo-controlled, and crossover study. After 3 days of drug treatment, individualized allergen challenges were given once daily for 7 days while the treatment continued. The washout periods between each of the challenge series were 2 weeks. Nasal symptoms and PIF were recorded in the morning and evening, as well as 10 and 20 min after each allergen challenge. The mean recordings obtained during the last 3 days of the allergen-challenge series, when symptoms were established and when the treatment had lasted for 8,10 days, were used in the analysis. Results Both active treatments reduced nasal symptoms and improved nasal PIF compared with placebo (P<0.01,0.001). There was no overall difference in efficacy between rofleponide palmitate 400 ,g and budesonide 128 ,g. Conclusions Topical treatment with aqueous solutions of rofleponide palmitate attenuates nasal symptoms and improves nasal PIF in allergic rhinitis. The overall efficacy of 400 ,g of rofleponide palmitate is similar to that of 128 ,g of budesonide in the pollen-season model used in this study. [source] Residues of zeta-cypermethrin in bovine tissues and milk following pour-on and spray applicationPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 11 2001James T Rothwell Abstract The depletion of zeta-cypermethrin residues in bovine tissues and milk was studied. Beef cattle were treated three times at 3-week intervals with 1,ml 10,kg,1 body weight of a 25,g,litre,1 or 50,g,litre,1 pour-on formulation (2.5 and 5.0,mg zeta-cypermethrin kg,1 body weight) or 100,mg,kg,1 spray to simulate a likely worst-case treatment regime. Friesian and Jersey dairy cows were treated once with 2.5,mg zeta-cypermethrin,kg,1 in a pour-on formulation. Muscle, liver and kidney residue concentrations were generally less than the limit of detection (LOD,=, 0.01,mg,kg,1). Residues in renal-fat and back-fat samples from animals treated with 2.5,mg,kg,1 all exceeded the limit of quantitation (LOQ,=, 0.05,mg,kg,1), peaking at 10 days after treatment. Only two of five kidney fat samples were above the LOQ after 34 days, but none of the back-fat samples exceeded the LOQ at 28 days after treatment. Following spray treatments, fat residues were detectable in some animals but were below the LOQ at all sampling intervals. Zeta-cypermethrin was quantifiable (LOQ,=, 0.01,mg,kg,1) in only one whole-milk sample from the Friesian cows (0.015,mg,kg,1, 2 days after treatment). In whole milk from Jersey cows, the mean concentration of zeta-cypermethrin peaked 1 day after treatment, at 0.015,mg,kg,1, and the highest individual sample concentration was 0.025,mg,kg,1 at 3 days after treatment. Residues in milk were not quantifiable beginning 4 days after treatment. The mean concentrations of zeta-cypermethrin in milk fat from Friesian and Jersey cows peaked two days after treatment at 0.197,mg,kg,1 and 0.377,mg,kg,1, respectively, and the highest individual sample concentrations were 2 days after treatment at 0.47,mg,kg,1 and 0.98,mg,kg,1, respectively. © 2001 Society of Chemical Industry [source] Epidemiology and management of Leptosphaeria maculans (phoma stem canker) on oilseed rape in Australia, Canada and EuropePLANT PATHOLOGY, Issue 1 2001J. S. West Phoma stem canker (blackleg), caused by Leptosphaeria maculans, is an important disease on oilseed rape (canola, rapeseed, Brassica napus, Brassica juncea, Brassica rapa) causing seedling death, lodging or early senescence in Australia, Canada and Europe, but not in China. The two forms of L. maculans (A group and B group) that occur on oilseed rape are now considered to be separate species. The epidemiology and severity of phoma stem canker differs between continents due to differences in the pathogen population structure, oilseed rape species and cultivars grown, climate and agricultural practices. Epidemics are most severe in Australia, where only the A group occurs, and can be damaging in Canada and western Europe, where both A and B groups occur, although their proportions vary within regions and throughout the year. Epidemics are slight in China, where the A group has not been found. Dry climates (Australia, western Canada) lengthen the persistence of infected debris and may synchronize the release of airborne ascospores (after rain) with seedling emergence. L. maculans spreads from cotyledon and leaf infections down petioles to reach the stem, with infections on cotyledons and leaves early in the season producing the most damaging stem cankers at the stem base (crown). Development of both crown cankers and phoma stem lesions higher up stems is most rapid in regions with high temperatures from flowering to harvest, such as Australia and Canada. Breeding for resistance (genetic, disease escape or tolerance), stubble management, crop rotation and fungicide seed treatments are important strategies for control of phoma stem canker in all areas. Fungicide spray treatments are justified only in regions such as western Europe where high yields are obtained, and accurate forecasts of epidemic severity are needed to optimize their use. [source] | ||||||||||