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1.
Metconazole, (1RS, 5RS; 1RS, 5SR)-5-(4-chlorobenzyl)-2,2-dimethyl-1-(1H-1,2,4-triazol-1-ylmethyl)cyclopentanol, is a highly active fungicide, in particular controlling seed-borne and foliar diseases of cereals, such as wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.). In order to maximize its foliar activity, an experimental survey of some types of surfactants and an emulsifiable oil was undertaken. Two types of metconazole formulation were investigated using a biological assay involving the therapeutic control of two diseases (Erysiphe graminis DC f. sp. tritici Marchal and Leptosphaeria nodorum Muell.) of wheat. Enhancements of activity by ?Genapol’? C12/C14 alcohol ethoxylates of an emulsifiable concentrate (ECM) formulation of metconazole were approximately three- to four-fold. For its, initially, less active suspension concentrate (SCM) formulation, enhancements were around 35-fold, so that with these adjuvants the two formulations were of similar activity. The enhancement ability of these ?Genapol’? surfactants was optimal at lower (5–10 moles) ethylene oxide content. These analogues induced marginally better enhancements of activity than members of a range of nonylphenol ethoxylates (?Arkopal’?), and emulsifiable paraffinic/naphthenic oil (HVI 60E) and a castor oil ethoxylate (?Atlas’? G1281) but were equivalent to a similar series of alcohol ethoxylates (?Dobanol’?) from another source. Varying the alkyl chain length between C9-C11 and C14-C15 in the ?Dobanol’? series had little effect on their high enhancements of metconazole activity. It was determined from trials varying the application rate of the best alcohol ethoxylates that application rates of 1–1.5 kg ha?1 were required for maximum activity. This implied the use of high adjuvant/metconazole ratios in one-pack adjuvant-containing formulations. A range of soluble liquid (SL) formulations were prepared with either ?Dobanol’? 23–6.5 or ?Dobanol’? 91-6/metconazole ratios varying from 5:1 to 15:1. There were found to be highly active and were recommended for field testing.  相似文献   

2.
A field study is described which explored the possibility of controlling Stagonospora nodorum and Septoria tritici on wheat using a barley pathogen, Drechslera teres. Pre-treatment of wheat cv. Hussar flag leaves with D. teres resulted in a significant reduction in disease caused by S. nodorum and S. tritici, resulting in a significant increase in grain yield. When cv. Brigadier leaves were treated with D. teres prior to inoculation with S. nodorum there was an initial increase in disease expression whilst D. teres had no effect on symptoms produced by S. tritici on cv. Brigadier. There was significantly less disease on leaves of cvs. Hussar and Brigadier pre-treated with D. teres prior to inoculation with an equal mixture of S. nodorum and S. tritici compared to plants pre-treated with water. It is concluded that D. teres and other non-host pathogens show potential as biological control agents for S. nodorum and S. tritici.  相似文献   

3.
A field trials programme was conducted in which the performance of a new emulsifiable concentrate formulation (ECI) of flamprop-M-isopropyl containing the adjuvant, ‘Dobanol’ 25-7, in a ratio of 2:1 (by weight) with the AI, was compared with the current commercial formulation of ‘Commando’, in combination with its recommended adjuvant, ‘Swirl’, for the control of wild oat (Avena fatua L.) in wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.). A further treatment, in which the ‘Dobanol’ 25-7: AI ratio was increased to 4:1 by the spray tank addition of the former, was also included. The mean results from six trials (five wheat, one barley) showed that the addition of ‘Swirl’ to ‘Commando’ was beneficial, increasing wild oat floret control from a mean value of 80% to 92% at current recommended rates (flamprop-M-isopropyl, 600 g ha?1; ‘Swirl’, 2.5 litre ha?1). However, combinations of flamprop-M-isopropyl and ‘Dobanol’ 25-7 gave superior levels of control even at lower AI application rates. For example, a mean level of 96% control of Avena spp. was obtained at 300 g AI ha?1 with 1200 g ha?1 ‘Dobanol’ 25–7; with even better control at higher rates of application of both components. This improvement in performance was accompanied by a higher risk of crop phytotoxicity than observed with the ‘Commando’/‘Swirl’ mixtures. Symptoms initially were scorch and subsequently growth depression, particularly of tillers. None of the mean values in the six ‘efficacy’ trials reached commercially unacceptable levels, but in a further six ‘crop effects’ trials (three wheat, three barley), in which double rates were applied, the levels of phytotoxicity did become unacceptable and subsequently reduced grain yields. In contrast, two barley ‘crop effects’ trials gave yields higher than the control plots, possibly through the effects of reducing stem length and lodging thereby enabling more efficient harvesting. Nevertheless, there were rates of application of flamprop-M-isopropyl in the range 300–400 g ha?1 with ratios of ‘Dobanol’ 25-7 in the range 2:1 to 4:1 that would achieve high levels of control of Avena spp. without undue risk of crop phytotoxicity and further trials are planned to support this new adjuvant system.  相似文献   

4.
Previous investigations have shown that certain C12–C18 alcohol ethoxylates with between 5 and 20 moles ethylene oxide gave large enhancements to the therapeutic activity of emulsifiable concentrate (EC) and wettable power (WP) formulations of dimethomorph in controlling two-day-old infections of downy mildew (Plasmopara viticola, Berl. & deT) on glasshouse propagated vines (Vitis vinifera, L.). In a continuation of that work it has been shown that similar enhancements could also be obtained on vines that had been grown under outdoor conditions for two to three weeks before treatment (outdoor-hardened vines) and it is concluded that the treatments would therefore be effective on field vines. Mixtures of either ammonium sulfate or the silicone ethoxylate, ‘Silwet’ L77, with the best alcohol ethoxylates, ‘Genapol’ C050 or ‘Genapol’ C080, produced slight antagonism of the action of the ‘Genapols’ and therefore were of no benefit. Trials with one-pack formulations prepared containing the ‘Genapol’ adjuvants produced good dose response curves from which estimated doses for 90% fungal control (ED90 values) could be calculated by Logit analysis. These one-pack formulations were significantly more effective than the standard EC formulation (ED90=335 g AI ha−1, glasshouse vines and 445 g AI ha−1, outdoor hardened vines) with optimum enhancements with those formulations containing an adjuvant: dimethomorph ratio of either 9:1 on glasshouse vines (ED90= 13 g AI ha−1) or 6:1 on outdoor-hardened vines (ED90=30 g AI ha−1). This last result was significantly better than that obtained with a commercial formulation of cymoxanil, ‘Fytospore’, (ED90=86 g AI ha−1) and encouraged the recommendation that these one-pack formulations should be examined in field trials.  相似文献   

5.
The effect of adjuvants on the performance of emulsifiable concentrate (EC) and wettable powder (WP) formulations of dimethomorph, a new systemic Oomycete fungicide, has been investigated using a two-day therapeutic (curative) assay with downy mildew (Plasmopara viticola, Berl. & de T.) on vines (Vitisvinifera L., cv. Cabernet Sauvignon) in glasshouse trials. The EC formulation had some therapeutic activity in this type of test. This activity was increased by the spray tank incorporation of 6 g litre−1 of either emulsifiable rape seed oil (‘Atplus’ 412) or emulsifiable paraffinic oil (‘Atplus’ 411F). However, these improvements in performance were overshadowed by those brought about by incorporation of 3 g litre−1 of a series of C13/C14 alcohol ethoxylates varying in ethylene oxide content from 5 to 20 moles:(‘Marlipal’ 34/6EO, 34/11EO, 34/20EO). Nearly complete fungal control was obtained in the presence of these adjuvants with a dimethomorph application rate of 25 g ha−1 compared with only around 90% control at 400 g ha−1 without adjuvants. The WP formulation was inactive in this therapeutic test but the presence of the adjuvants improved the performance of this formulation towards the high levels observed with the EC plus adjuvants, demonstrating that adjuvants could markedly influence the performance of solid, otherwise therapeutically inactive, dimethomorph formulations. Further trials examined other types of adjuvants (nonylphenol, alkylamine and silicone ethoxylates) but either they were no better than the alcohol ethoxylates or they induced unacceptable phytotoxicity. Trials with alcohol ethoxylates (‘Genapols’) from another source demonstrated activity equivalent to the ‘Marlipal’ surfactants. A two-factorial matrix experiment with ‘Genapol’ C050 showed that, under glasshouse conditions, >90% control could be obtained with the dimethomorph EC at 25 g AI ha−1 with 375 g ha−1 ‘Genapol’ C050. Applications of the WP formulation required slightly higher rates of either 50 g AI ha−1 plus 375 g ha−1 ‘Genapol’ C050 or 25 g AI ha−1 plus 750–1500 g ha−1 ‘Genapol’ C050. The overall conclusion was that alcohol ethoxylates varying in alkyl chain length from C12 to C18 and ethylene oxide content between 5 and 20 moles for the C12 surfactants and ∽15 moles for the C18 surfactants were effective adjuvants in promoting the therapeutic activity of dimethomorph formulationsagainst P. viticola on glasshouse-propagated vines.  相似文献   

6.
Chlorsulfuron, giyphosate and imazaquin were evaluated in pot and field studies for their efficacy in controlling broomrape (Orobanche ramosa L.) in tomato (Lycopersicon esculentum Mill.) in Northern Greece. All herbicides were applied four to five weeks after tomato transplanting, when the crop was at early flowering stage and broomrape had started to develop underground attachments. The number of emerged broomrape shoots and underground attachments were less affected by herbicide treatments than the dry weight, suggesting that the herbicides suppress the growth of broomrape rather than kill its underground organs. In the pot experiments, chlorsulfuron applied at 5 g AI ha?1 was the most effective treatment for broomrape control and the least toxic to the crop. Imazaquin and glyphosate applied at 37 and 180 g AI ha?1, respectively, controlled broomrape but imazaquin reduced crop yield. In the field, similar rates of glyphosate and higher rates of imazaquin were not toxic to the crop but were less effective on broomrape. Chlorsulfuron applied at 10 g AI ha?1 controlled broomrape emergence by 88%. When the herbicide was applied twice (5+10 g AI ha?1), it gave complete control of broomrape but delayed crop maturity. The yield of tomato was not increased as a result of these treatments because of low broomrape infestation and a short competition period.  相似文献   

7.
BACKGROUND: Proquinazid is a new quinazolinone fungicide from DuPont registered in most European countries for powdery mildew control in cereals and vines. The aim of this paper is to present baseline sensitivity data in populations of Blumeria graminis f. sp. tritici EM Marchal and Erysiphe necator (Schw) Burr as well as results from cross‐resistance studies with other fungicides. RESULTS: Proquinazid exhibited a high intrinsic activity on B. graminis f. sp. tritici isolates at rates ranging from 0.000078 to 0.02 mg L?1. Erysiphe necator isolates were comparatively less sensitive to proquinazid, with EC50 values ranging from 0.001 to 0.3 mg L?1. Proquinazid controlled equally well B. graminis f. sp. tritici isolates sensitive and resistant or less sensitive to tebuconazole, fenpropimorph, fenpropidin, cyprodinil and kresoxim‐methyl. A positive correlation (r = 0.617) between quinoxyfen and proquinazid sensitivities was found among 51 B. graminis f. sp. tritici isolates. Quinoxyfen‐resistant B. graminis f. sp. tritici isolates were slightly less sensitive to proquinazid than the quinoxyfen‐sensitive isolates; however, proquinazid remained much more active than quinoxyfen on these isolates. A stronger sensitivity relationship (r = 0.874) between proquinazid and quinoxyfen was found among 65 E. necator isolates tested in a leaf disc assay. The sensitivity values for proquinazid were significantly lower than those for quinoxyfen, confirming the higher intrinsic activity of proquinazid on both pathogens. CONCLUSION: Given the history of resistance development in powdery mildew and the observed sensitivity relationship with quinoxyfen, specifically in E. necator, we conclude that the risk of resistance developing to proquinazid might be influenced by the use of quinoxyfen. Based on these results, the authors recommend that proquinazid and quinoxyfen be managed together for resistance management. Copyright © 2009 Society of Chemical Industry  相似文献   

8.
Interactions between Stagonospora nodorum and Septoria tritici were studied. Results from a detached glume experiment indicated that the interaction may be isolate-dependent, as it was shown that the interaction between the two pathogens may be beneficial or antagonistic depending on the isolate of each pathogen present. The number of spores produced by both pathogens was significantly greater when an aggressive isolate of S. tritici was mixed with a non-aggressive isolate of S. nodorum, whereas the number of spores produced by both pathogens was significantly less when two non-aggressive isolates were mixed. There was a significant reduction in disease level when S. tritici was applied prior to S. nodorum, compared to vice versa in the growth chamber. Results from growth chamber and field studies showed that S. nodorum produced significantly more spores when both pathogens were present together. It is concluded that S. tritici has a stimulatory effect on spore production by S. nodorum. However, there was a reduction of S. tritici spores observed in the dual inoculation treatments, suggesting that S. nodorum inhibits S. tritici.  相似文献   

9.
The effects of two herbicides, glyphosate (as a 359 g litre?1 SL) and hexazinone (as a 50gkg?1 granule) on soil microbial population, carbon dioxide evolution, and in-vitro growth of five species of ectomycorrhizal fungi were investigated. Glyphosate at 0–54 and 3.23 kg a.i. ha?1 and hexazinone at 1. 2 and 8 kg a.i. ha?1 did not reduce soil microbial population or carbon dioxide evolution in the long term (6 months). However, there was a significant short-term (2 months) effect of glyphosate on both fungal and bacterial counts at the 0.54 kg ha?1 treatment. In in-vitro tests, Cenococcum graniforme. Hebeloma crustuliniforme and Laccaria laccata were more susceptible to both herbicides than was Suillus tomentosus. which was, in turn, more susceptible than Paxillus involutus. The growth of all five ectomycorrhizal fungi was significantly reduced when subjected to concentrations above 50 μl formulation litre?1 (glyphosate) or 50 μg formulation litre?1 (hexazinone).  相似文献   

10.
The dose-response, foliar uptake, translocation and metabolism of the methylheptyl ester (MHE) of fluroxypyr were examined in lambs-quarters (Chenopodium album L.), wild buckwheat (Polygonum convolvulus L.), Canada thistle (Cirsium arvense L. Scop.) and field bindweed (Convolvulus arvensis L.). Under controlled environment growth room conditions, E50 values, determined from shoot dry weights of the susceptible species, wild buckwheat (16 g ha?1) and field bindweed (40 g ha?1), were markedly different than those of the tolerant species, lambsquarters (331 g ha?1) and Canada thistle (800 g ha?1). Regardless of species, more than 80% of applied [14C]fluroxypyr-MHE was absorbed by foliar surfaces 120 h after treatment. Translocation of radioactivity out of the treated leaves of susceptible species was significantly greater than that of tolerant species. For example, 120 h after treatment with [14C]-fluroxypyr-MHE, the proportion of applied radioactivity translocated in tolerant Canada thistle and lambsquarters was 15 and 10%, respectively, whereas in susceptible wild buckwheat and field bindweed it was 41 and 40% of applied radioactivity, respectively. High-performance liquid chromatography (HPLC) of plant extracts indicated four distinct chroma-tographic peaks common to all four species. More fluroxypyr was recovered in the susceptible species (70%) than in the tolerant species (30%), 120 h after application. Selectivity differences between the tolerant and susceptible species may be the result of enhanced metabolic transformation of the herbicide to more polar, non-phytotoxic compounds with limited mobility within the tolerant species. Les bases de la sélectivité du fluroxypyr La courbe dose effet, la pénétration foliaire, la migration et le métabolisme de Tester méthyle-heptyle (MHE) du fluroxypyr ont étéétudiés chez le chénopode blanc (Chenopodium album L.), la renouée faux-liseron (Polygonum con-vulvulus L.), le chardon des champs (Cirsium arvense L. Scop.) et le liseron des champs (Convolvulus arvensis L.). En conditions de crois-sance contrôlées, les valeurs ED50, déterminées à partir du poids de matière sèche des parties aériennes étaient nettement différentes chez les plantes sensibles et chez les plantes résistan-tes:renouée faux-liseron, 16 g ha?1; liseron des champs, 40 g ha?1; chénopode blanc, 331 g ha?1; chardon des champs, 800 g ha?1. Quelle que soit 1'espèce, plus de 80% du [14C]fluroxypyr-MHE pénétrait dans les feuilles en 120 h. La migration de la radioactivité hors des feuilles traitérs était significativement plus importante chez les plantes sensibles que chez les plantes tolérantes. Par exemple, 120 h après le traite-ment avec du [14C]fluroxypyr-MHE, la proportion de radioactivité appliquée qui avait migré dans le chardon des champs et le chénopode, tolérants, était respectivement 15 et 10%, alors que chez la renouée faux-liseron et le liseron des champs, sensibles, elle était respectivement 41 et 40%. Des analyses par HPLC des extraits de plantes montraient quatre pics chro-matographiques distincts dans chacune des quatre espèces. Davantage de fluroxypyr était retrouvé 120 h après 1'application chez les plantes sensibles que chez les plantes résistantes (70% contre 30%). Les différences de sensibilité entre espèces pourraient être dues chez les plantes tolérantes à un métabolisme plus important de l'herbicide en composés plus polaires, non phytotoxiques et peu mobiles. Grundlagen für die selektive Wirkung von Fluroxypyr Die Dosis/Wirkungs-Beziehung, Blattaufnahme, Translokation und Metabolismus des Methylheptyl-Esters (MHE) von Fluroxypyr wurden bei Weißem Gänsefuß (Chenopodium album L.), Gemeinem Windenknöterich (Polygonum convolvulus L.), Acker-Kratzdistel (Cirsium arvense (L.) Scop.) und Gemeiner Ackerwinde (Convolvulus arvensis L.) untersucht. Unter den kontrollierten Umweltbedingungen eines Phytotrons wurden anhand des Trockengewichts die ED50-Werte bestimmt, die bei den empfindlichen Arten Polygonum convolvulus mit 16 g ha?1 und Convolvulus arvensis mit 40 g ha?1 sich deutlich von denen der toleranten Arten Chenopodium album mit 331 g ha?1 und Cirsium arvense mit 800 g ha?1 unterschieden. Unabhängig von der Art waren mehr als 80 % der Aufwandmenge von [14C]-Fluroxypyr-MHE durch die Blattoberflächen 120 h nach der Behandlung aufgenommen. Die Translokation der Radioaktivität aus den behandelten Blättern war bei den empfindlichen Arten signifikant größer als bei den toleranten. Z. B. waren 120 h nach der Behandlung bei den toleranten Arten Cirsium arvense und Chenopodium album 15 bzw. 10 % der Radioaktivität transloziert, während es bei den empfindlichen Arten Polygonum convolvulus und Convolvulus arvensis 41 bzw. 40 % waren. Bei allen 4 Arten ergab eine HPLC-Untersuchung der Pflanzenextrakte 4 distinkte Peaks. Bei den empfindlichen Arten wurde 120 h nach der Anwendung mit 70 % mehr Fluroxypyr wiedergefunden als bei den toleranten (30 %). Die Selektivitätsunterschiede zwischen den toleranten und empfindlichen Arten könnten auf einen beschleunigten Metabolismus des Herbizids zu stärker polaren, nichphytotoxischen Stoffen mit eingeschränkter Mobilität bei den toleranten Arten zurückgeführt werden.  相似文献   

11.
Experiments were conducted in a controlled environment growth room to compare the phytotoxicity of five formulations of clopyralid and to determine the effect of post-treatment simulated rainfall applications on the efficacy of these formulations. Clopyralid, formulated as the acid, monoethanolamine salt, potassium salt, 2-ethylhexyl ester or 1-decyl ester was applied to Cirsium arvense or Polygonum convolvulus at the 8–10 and 4–6 leaf stage of development, respectively. Based on the shoot and root dry weight data from both species, the 2-ethylhexyl ester was consistently less phytotoxic than the other four formulations. With respect to Cirsium arvense shoot and root dry weight, there was no difference in efficacy between the acid, monoethanolamine salt, potassium salt and 1-decyl ester. Root dry weight changes of Polygonum convolvulus did not correlate well with an increase in dose of the five formulations. Maximum increase in stem diameter of Polygonum convolvulus occurred after application of 100 g a.e. ha?1 of the acid, monoethanolamine salt, potassium salt and 1-decyl ester whereas with the 2-ethylhexyl ester, the maximum increase occurred after application of 200 g a.e. ha?1. Simulated rainfall was applied 3, 6, 9 or 12 h after application of 200 g a.e. ha?1 of the five clopyralid formulations to both species. Rainfall reduced the efficacy of clopyralid, regardless of the formulation or species. The 2-ethylhexyl ester was less efficacious than the other four formulations, irrespective of the timing of simulated rainfall.  相似文献   

12.
BACKGROUND: The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is a cosmopolitan insect pest of citrus and vectors the bacterium Candidatus Liberibacter asiaticus, a suspected causal organism of citrus greening or ‘huanglongbing’ disease. Aldicarb 150 g kg?1 GR (Temik® 15 G) was evaluated at three rates, two placements and three timings for ACP control in orange trees. RESULTS: Application of aldicarb at 5.6, 2.8 and 1.4 kg AI ha?1 in March 2006 reduced adults by 58–66%, 45–46% and 25–37% respectively compared with untreated controls in two separate trials. No difference was observed in placement (one versus two sides of the tree) or tree size (8 years old versus 12 years old). Application at 5.6 kg ha?1 in January 2007 reduced adults by 86% and shoot infestation by 77% in spring, and was generally better than the November and especially February applications. Even more striking results were evident on adults caged on treated plants for 25 days in March. Spiders and ladybeetles were equally abundant in treated and untreated trees. CONCLUSION: Aldicarb application at 5.6 kg ha?1 to the bed side of mature citrus trees 2–3 months before spring growth can suppress ACP through spring without a direct effect on principal psyllid natural enemies. Copyright © 2008 Society of Chemical Industry  相似文献   

13.
The potential of the fungicide tridemorph selectively to control established plants of Holcus lanatus L. in ryegrass (Lolium perenne L) and Bromus sterilis L. in barley (Hordeum vulgare L.) was examined in glasshouse trails. A dose of 4.2 kg ha?1 tridemorph gave selectively between H. lanatus and ryegrass similar to, but more costly than, that which would be provided by 1.2 kg ha?1 asulam. B sterilis was more sensitive to tridemorph than was barley. Two additives, glycerol and the oil-surfactant mixture ‘PF’ enhanced this selectivity when tridemorph was applied at 2.1 kg ha?1.  相似文献   

14.
In 1997 and 1998, five field studies were conducted at four Portuguese wine‐growing regions in order to evaluate the effectiveness of the chemical control of vineyard weeds under Mediterranean conditions using either reduced doses of residual herbicides or only foliar herbicides. Amitrole (3440 g a.i. ha?1), amitrole + glyphosate mono‐ammonium salt (1720 + 900 g a.i. ha?1), amitrole (3400 g a.i. ha?1), amitrole + diuron (2580 + 1500 g a.i. ha?1), amitrole + simazine (2580 + 1500 g a.i. ha?1), amitrole + terbuthylazine (2580 + 1500 g a.i. ha?1) and amitrole + diuron + simazine (2580 + 1300 + 1400 g a.i. ha?1) were assayed and compared with the following reference herbicides: glyphosate isopropylamine salt (1800 g a.i. ha?1), amitrole + diuron (2520 + 1680 g a.i. ha?1), diuron + glyphosate + terbuthylazine (1275 + 900 + 1425 g a.i. ha?1), amitrole + simazine (1900 + 3900 g a.i. ha?1) and glyphosate + simazine (800 + 2200 g a.i. ha?1). The herbicides were applied during late winter. The results indicated that good control was achieved by the application of foliar herbicides alone or of reduced rates of a mixture of residual herbicides with foliar herbicides for at least 2 months. Three months after application, the efficacy of post‐emergence herbicides and lower rates of residual herbicides decreased significantly in clay soils and under heavy rainfall conditions. Convolvulus arvensis– a weed that is becoming increasingly significant in Portuguese vineyards – was poorly controlled, even when glyphosate was used. Despite this, it can be assumed that in those regions in which the trials were conducted, it is possible to employ weed control strategies that entail the elimination or a reduction in the rate of residual herbicides.  相似文献   

15.
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   

16.
Biological characterization of sulfoxaflor, a novel insecticide   总被引：1，自引：0，他引：1  
BACKGROUND: The commercialization of new insecticides is important for ensuring that multiple effective product choices are available. In particular, new insecticides that exhibit high potency and lack insecticidal cross‐resistance are particularly useful in insecticide resistance management (IRM) programs. Sulfoxaflor possesses these characteristics and is the first compound under development from the novel sulfoxamine class of insecticides. RESULTS: In the laboratory, sulfoxaflor demonstrated high levels of insecticidal potency against a broad range of sap‐feeding insect species. The potency of sulfoxaflor was comparable with that of commercial products, including neonicotinoids, for the control of a wide range of aphids, whiteflies (Homoptera) and true bugs (Heteroptera). Sulfoxaflor performed equally well in the laboratory against both insecticide‐susceptible and insecticide‐resistant populations of sweetpotato whitefly, Bemisia tabaci Gennadius, and brown planthopper, Nilaparvata lugens (Stål), including populations resistant to the neonicotinoid insecticide imidacloprid. These laboratory efficacy trends were confirmed in field trials from multiple geographies and crops, and in populations of insects with histories of repeated exposure to insecticides. In particular, a sulfoxaflor use rate of 25 g ha?1 against cotton aphid (Aphis gossypii Glover) outperformed acetamiprid (25 g ha?1) and dicrotophos (560 g ha?1). Sulfoxaflor (50 g ha?1) provided a control of sweetpotato whitefly equivalent to that of acetamiprid (75 g ha?1) and imidacloprid (50 g ha?1) and better than that of thiamethoxam (50 g ha?1). CONCLUSION: The novel chemistry of sulfoxaflor, its unique biological spectrum of activity and its lack of cross‐resistance highlight the potential of sulfoxaflor as an important new tool for the control of sap‐feeding insect pests. Copyright © 2010 Society of Chemical Industry  相似文献   

17.
Fluazifop-butyl, haloxyfop and sethoxydim with adjuvant oil were applied for three successive growing seasons to established strawberries infested with Elymus repens. The weed was virtually eradicated by three applications of haloxyfop (0.8 kg a.e. ha?1) in successive years. A similar effect was given by five applications of haloxyfop (0.4 kg a.e. ha?1) and fluazifop-butyl (1.6 kg AI ha?1) in three growing seasons. Lower rates of haloxyfop and fluazifop-butyl, and a high rate of sethoxydim (1.6 kg AI ha?1) applied five times were less effective, the ground cover of E. repens shoots not being reduced by the end of the experiment although weight of living rhizome was only 10-30% of that on untreated plots. Fruit yields on treated plots generally reflected the level of E. repens control, but there was some evidence of crop phytotoxicity from herbicide treatments. During the experiment E. repens untreated plots increased from about 30-100% ground cover and reduced yield 13, 28 and 68% in successive years compared with weed-free plots.  相似文献   

18.
Field experiments were conducted from 1989 to 1992 to determine the effects of pre-emergence herbicides in sunflower (Helianthus armuus L.) on: (1) the control of Orobanche cemua Loefl. (broomrape) and (2) crop damage and crop yield. Herbicides tested belong to the imidazolinone, sulfonylurea and substituted amide families. Imazethapy r (20–40 g ha?1), imazapy r (12.5–25 gha?1) and chlorsulfuron (4–6 gha?1) controlled broomrape efficiently without crop injury. With good O. cernua control and good crop tolerance, sunflower seed yield from these treatments were generally similar to the non-infested checks and higher than the infestedchecks. Imazaquin (20–40 gha?1), triasulfuron(4gha?1), pdmisulfuron(3g ha?1), acetochlor (4–4 kg ha?1) and metazachlor (2 kg ha?1) were less effective. Imazamethabenz (200–600 g ha?1) and metolachlor (3–3 kg ha?1) were ineffective. Wetconditions aftercropsowing considerably decreased O. cemua control with pre-emergence herbicides probably caused by enhanced degrädation. Des herbicides de prelevee pour la lutte contre Vorobanche (Orobanche cemua Loefl.) dans le toumesol (Helianthus annuus L.) Des expérimentations au champ ont été conduites de 1989 á 1992 pour determiner les effets d'herbicides de pré1evée du toumesol sun (a) la destruction de l'orobanche (Orobanche cernua Loefl.) et (b) la phytotoxcité sur la culture. Les herbicides testés appartenaient aux imidazolinones, aux sulfonylurdes et aux amides substituées. L'imazethapyr (20 á 40 gha?1), l'imazapyr (12,5 á25gha?1)et le chlorsulfuron (4 á 6 gha?1) détruisaient efficacement l'orobanche sans occasionner de phytotoxidt6 sur la culture. Dans ces conditions, les rendements étaient généralement semblables à ceux des témoins non infestés et supérieurs à ceux des témoins infestés. L'imazaquin (20 à 40 g ha?1), le triasulfuron (4 gha?1), le primisulfuron (3 g ha?1), lacétolachlor (4,4 kg ha?1) et le métazachlor (2 kg ha?1) étaient moins efficaces. L'imazaméthabenz (200 á 600 g ha?1) et le métolachlor (3,3 kg ha?1) etaient inefficaces. Des conditions humides aprfes le semis diminuaient considérablement la destruction de O. cemua par les herbicides de prélevée, probablement à cause d'une dégradation plus élevée. Vorauflaufherbigide zur Bekdmpfung der Sommerwurz Orobanche cemua Loefl. in Sonnenblume (Helianthus annuus L.) Zwischen 1989 und 1992 wurden in Sonnenblume Feldversuche zur Wirkung von Vorauflaufherbiziden aus den Gruppen der Imidazolinone, Sulfonylharnstoffe und substitutierten Amide auf die Sommerwurz Orobanche cernua und auf Kulturpflanzenschaden sowie den Ertrag durchgefuhrt. Mit Imazethapyr (20 bis 40 g ha?1), Imazapyr (12,5 bis 25 g ha?1) und Chlorsulfuron (4 bis 6 g ha?1) lieβ sich die Sommerwurz wirksam bekampfen, ohne daβ Schaden an der Sonnenblume auftraten, und die Ertrage waren allgemein ahnlich oder hoher als bei der nichtparasitierten Kontrolle. Imazaquin (20 bis 40 ha?1), Triasulfuron (4 g ha?1).Primisulfuron (3 g ha ?1). Acetochlor (4,4 kg ha ?1 und Metazachlor (2 kg ha ?1) waren weniger wirksam. Imazamethabenz (200 bis 600 g ha?1) und Metolachlor (3,3 kg ha?1) hatten keine Wirkung. Bei Niederschlagen nach der Saat der Sonnenblume war die Bekampfung der Sommerwurz mit Vorauflaufherbiziden vermutlich wegen verstärkten Abbaus erheblich schwächer.  相似文献   

19.
BACKGROUND: A mixture of trifloxystrobin and tebuconazole is excellent in controlling both powdery and downy mildew of grapes. The objective of the present work was to study the behaviour of trifloxystrobin and tebuconazole on grape berries and soil following treatment with Nativo 75 WG, a formulation containing both fungicides (trifloxystrobin 250 + tebuconazole 500 g kg?1). This study was carried out for planned registration of this mixture for use on grapes in India. RESULTS: Initial residue deposits of trifloxystrobin and tebuconazole on grapes were below their maximum residue limit (MRL) of 0.5 and 2 mg kg?1, respectively, when Nativo 75 WG was applied at the recommended dose of 175 g product ha?1. The residues dissipated gradually to 0.02 and 0.05 mg kg?1 by 30 days, and were below the quantifiable limit of 0.01 mg kg?1 at the time of harvest (60 days after the last treatment). Trifloxystrobin and tebuconazole dissipated at a pre‐harvest interval (PHI) of 36 and 34 days, respectively, from the recommended treatment dose. The acid metabolite of trifloxystrobin, CGA 321 113, was not detected in grape berries at any point in time. Soil at harvest was free of any pesticide residues. CONCLUSION: Residue levels of both trifloxystrobin and tebuconazole were below MRLs when grapes were harvested 30 days after the last of four applications of 175 g product ha?1 (trifloxystrobin 44 g AI ha?1, tebuconazole 88 g AI ha?1) under the semi‐arid tropical climatic conditions of India. Copyright © 2010 Society of Chemical Industry  相似文献   

20.
Petroleum spray oil (2, 4 and 6% in water) was applied to Valencia orange, Citrus sinensis (L.) Osbeck, for the control of Chinese wax scale, Ceroplastes sinensis del Guercio, using a low-volume ( <2000 litre ha?1)air-blast (LV AB) sprayer, a low- to high-volume (L-HV) (up to 7000 litre ha?1) sprayer with four fan-assisted rotary atomiser (FARA) spray heads mounted on a vertical tower, and a high-volume (>7000 litre ha?1) oscillating boom (HV OB) sprayer. The most effective sprayer was the L-HV FARA sprayer. The most cost-effective treatment was a 20 ml litre?1 (60 litre oil ha?1) spray applied at 3000 litre ha?1 by the L-HV FARA sprayer. It gave mortality equivalent to a standard 20 ml litre?1, 10 700 litre ha?1 spray (214 litre oil ha?1) applied by the HV OB sprayer but with 72% less spray and significantly less oil deposited per cm2 of leaf area. Equivalent or significantly (P = 0·05) higher mortality than that given by the 10 700 litre ha?1 HV OB spray was given by the 40 ml litre?1, 3000 (120 litre oil ha?1) and 60 ml litre?1, 2180 and 3000 litre ha?1 (130·8 and 180 litre oil ha?1) L-HV FARA sprays, but the 60 ml litre?1 sprays deposited more oil per cm2 than the 20 ml litre?1 HV OB spray and were considered to be potentially phytotoxic. The least effective sprayer was the LV AB sprayer, which applied a 60 ml litre?1 spray (57·6 litre oil ha?1) at 960 litre ha?1. Linear relationships were established for Chinese wax scale mortality, transformed using an angular transformation (arcsin proportion), versus log10 spray volume for the 20, 40 and 60 ml litre?1 sprays applied by L-HV FARA at 1260,2180 and 3000 litre ha?1, mortality versus log10 μg oil cm?2 and log10 μg oil versus log10 volume of oil sprayed.  相似文献   

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