RESUMEN
Crop protection is mainly achieved by applying Plant Protection Products (PPP) using hydraulic nozzles, which rely on pressure, to produce a wide droplet size distribution. Because of always increased concerns about drift reduction, a wider range of low drift nozzles, such as air induction nozzles, was adopted in order to reduce the finest part of the spray. While successful for some treatments, the efficiency of coarser sprays is dramatically reduced on small and superhydrophobic target, i.e. at early stage weed control. This may be related to the increased proportion of big bouncing and splashing droplets. On the other hand, Controlled Droplet Application (CDA), using shielded rotary atomizers, stands for an improved control of droplets diameters and trajectories compared to hydraulic nozzles. Unfortunately, these atomizers, because of their horizontal droplet release, are widely recognized to produce more drift than hydraulic nozzles. The present contribution investigates whether the setting of a rotary atomizer 60 degrees forward tilted can reduce drift to acceptable levels in comparison with vertical and 60 degrees forward tilted standard and low drift flat fan nozzles for the same flow rate. In a wind tunnel, the drift potential of a medium spray produced by a tilted shielded rotary atomizer Micromax 120 was benchmarked with that of a flat fan nozzle XR11002 fine spray and that of an anti-drift nozzle Hardi Injet 015 medium spray. Operating parameters were set to apply 0.56 l/min for every spray generator. Vertical drift profiles were measured 2.0 m downward from nozzle axis for a 2 m.s(-1) wind speed. The tilted hydraulic nozzles resulted in a significant drift increase while droplets trajectories are affected by the decrease of the droplet initial vertical speed. Droplets emitted by the shielded rotary atomizer drift due to low entrained air and turbulence. A significant reduction of the cumulative drift was achieved by the rotary atomizer in comparison with flat fan nozzle while still being higher than the anti-drift nozzle. Unfortunately, the drift potential index (DIX) revealed that the cumulative drift reduction may not results in actual drift decrease because of higher drift at higher sampling locations. As a result, the DIX of the shielded rotary atomizer was similar to the standard flat-fan nozzle while the anti-drift nozzle reduced drastically drift as intended. Therefore, the 60 degrees tilted rotary atomizer failed to reach low drift levels as expected despite the reduced span.
Asunto(s)
Control de Plagas/instrumentación , Plaguicidas/química , Agricultura , Tamaño de la Partícula , Control de Plagas/métodos , VientoRESUMEN
The objective of this study was therefore to develop a formulation of conidia of T. asperellum with the aim of improving its efficacy. The formulations developed were oily dispersions. It was a combination of solvents consisting of groundnut oil or palm oil with structural agents and emulsifying-dispersing agents. Emulsification tests were carried out and the stability of the emulsions evaluated. The evaluation of the effect of co-formulants on the growth of conidia of T. asperellum was done by reading the optical densities of the formulated samples on multi-plates using a plate reader. The test on detached cocoa pods was done by treating the cocoa pods with selected formulations at 1.10(7) conidia/ml and inoculation of the treated cocoa pods was done 24 hours later with zoospores of P. megakarya at 1.10(5) zoospores/ml. The growth of necrosis on the fruits was measured daily. The screening of co-formulants and emulsification tests ended up with the selection of two formulations. The first composed of conidia of T. asperellum, groundnut oil, Tensiofix NTM and Tensiofix 869. The second differed from the first by utilisation of palm oil as the solvent. These formulations proved stable when diluted in water with 1% and 0.5% of sedimentation respectively after 24 hours. The viability test of the conidia indicated that the different formulations selected did not have a fungitoxic effect. The test on detached cocoa pods showed an improved efficacy of T. asperellum to control the disease. The growth rates of necrosis were 6.29 mm/day, 7.25 mm/day and 31.6 mm/day for treatment with formulation 1, pure conidia and control treated with water respectively.
Asunto(s)
Cacao , Phytophthora/efectos de los fármacos , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Esporas Fúngicas/química , Trichoderma/química , Aceite de Palma , Aceite de Cacahuete , Aceites de Plantas/química , Aceites de Plantas/farmacología , Trichoderma/clasificaciónRESUMEN
Assessing the dermal exposure of applicators to pesticides is still an important issue, and the measurement methods used remain open to improvement. This is particularly true when it comes to characterising the exposure of applicators using back-pack sprayers. The scenarios used for the different mathematical models continue to be riddled with approximations and uncertainties. With a view to improving these scenarios, test were performed in an open environment to measure the levels of dermal exposure on various parts of an operator's body during treatment with this type of equipment. The main parameters studied are the presence of vegetation and the height of the crop. The method uses a tracer (fluorescein salt) and collectors placed all over the body in order to determine which parts are subject to most contamination during spraying. The quantitative determinations of the tracer show that exposure, in the presence of vegetation, reaches levels of 0.02%, 0.006% and 0.04% of the total quantity applied in treatment, at heights of 0.5, 1 and 2 m respectively. In the absence of vegetation, it stands at 0.21%, 0.61% and 0.62% of the total quantity applied at heights of 0.5, 1 and 2 m. In each of these situations, the lower limbs of the body (shins and thighs) collected large proportions of fluorescein. The contamination of the upper parts of the body increases in proportion to the height of treatment. These results show that the presence of vegetation and the spraying height are important parameters to be considered and to be integrated into the models, to validly assess the exposure of operators using a backpack sprayer.
Asunto(s)
Agricultura/instrumentación , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/toxicidad , Plaguicidas/toxicidad , Piel/efectos de los fármacos , Agricultura/métodos , Contaminantes Ambientales/análisis , Contaminantes Ambientales/química , Fluoresceína/química , Humanos , Exposición Profesional/prevención & control , Plaguicidas/análisis , Plaguicidas/química , Ropa de Protección , Medición de Riesgo , Piel/química , Espectrometría de FluorescenciaRESUMEN
In order to gain a better understanding of non-agricultural pesticide use and to prepare the legislative and technical dossiers required under the Water Framework Directive, between October 2006 and March 2007, two surveys were conducted of 97 Walloon communes and 65 districts of the Walloon Ministry of Public Works and Transport (MET) (General Directorates for Motorways and Roads and for Waterway Infrastructure). The questionnaire (26 questions on six topics) was sent by e-mail or fax, with a response rate of 60 out of 97 communes and 33 out of 65 districts. This article describes the environmental aspects of the surveys (health-related aspects are the subject of separate article). The surveys have brought to light a number of good practices (including zero pesticides) and a growing awareness of environmental issues among non-agricultural users. However, bad habits, legislation infringements and a failure to follow good plant protection practice are still a problem and pose major environmental risks (in the form of water pollution from pesticides). Information, awareness-raising and training therefore remain a priority for non-agricultural users.
Asunto(s)
Agricultura/métodos , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis , Plaguicidas/análisis , Concienciación , Bélgica , Guías como Asunto , Humanos , Plaguicidas/efectos adversos , Salud Pública , Opinión Pública , Política Pública , Medición de Riesgo , Contaminantes del Suelo/análisis , Encuestas y Cuestionarios , Contaminantes Químicos del Agua/análisisRESUMEN
In order to gain a better understanding of non-agricultural pesticide use and to prepare the legislative and technical dossiers required under the Water Framework Directive, between October 2006 and March 2007, two surveys were conducted of 97 Walloon communes and 65 districts of the Walloon Ministry of Public Works and Transport (MET) (General Directorates for Motorways and Roads and for Waterway Infrastructure). The questionnaire (26 questions on six topics) was sent by e-mail or fax, with a response rate of 60 out of 97 communes and 33 out of 65 districts. This article describes the health-related aspects of the surveys (environmental aspects are the subject of separate article). The surveys have brought to light a number of bad practices and a growing awareness of the non-agricultural users with respect to health risks. However, bad habits, legislation infringements and a failure to follow good plant protection practice are still a problem and pose major health risks (which endanger the operator and the public). Information, awareness-raising and, especially, training of people therefore remain a priority for non-agricultural users.
Asunto(s)
Concienciación , Exposición a Riesgos Ambientales , Plaguicidas/efectos adversos , Medición de Riesgo , Recolección de Datos , Humanos , Estilo de Vida , Plaguicidas/análisis , Encuestas y CuestionariosRESUMEN
Selectivity of pesticides to beneficial arthropods is a key data for the implementation of IPM program. In the context of field vegetables crop, a set of 16 fungicides, 17 herbicides and 14 insecticides commonly used in Belgium were tested on 5 indicator species: the parasitic hymenoptera Aphidius rhopalosiphi (De Stefani-Perez) (Hym., Aphidiidae), the aphid foliage dwelling predators Adalia bipunctata (L.) (Col., Coccinellidae) and Episyrphus balteatus (Dipt., Syrphidae) and the ground-dwelling predators Aleochara bilineata (Col., Staphyllinidae) and Bembidion lampros (Col., Carabidae). Pesticides were tested according a testing scheme including a first assessment on inert substrate (glass plates for adults of A. rhopalosiphi, larvae of A. bipunctata and E. balteatus, sand on adults of A. bilineata and B. lampros) and, for product that were toxic, a second assessment on natural substrate (barley seedlings for A. rhopalosiphi, french bean plants for A. bipunctato and E. balteatus and two type of soil for 8. lampros and A. bilineato). The effects of the product were assessed on basis on mortality, except for A. bilineata (Onion fly pupae parasitism). According to the final results obtained at the end of this testing scheme, the product were listed in toxicity class: green list if effect < or =30%, yellow list 30% < effect < 60% and orange list 60% < effect < or =80%. Products with toxicity higher than 80% on plants or on soils, or that reduce parasitism more than 80% on soil were put in red list and are not recommended for IPM. Results showed that all fungicides and herbicides were included in the green list except tebuconazole and boscalid + pyraclostrobin that were labeled as yellow for A. bipunctata. In opposite, no foliar insecticide was totally selective for all beneficial tested. However some products are in green list for one or several species. Soil insecticides were all are very toxic for ground dwelling arthropods and classed in red list. All results obtained during this study and further upgrade will be available on www.cra.wallonie.be/selectivite. In conclusions, fungicides and herbicides tested are compatible with IPM programs. For foliar insecticides, some treatments can be used carefully according to the selectivity. But for soil insecticide treatments, their toxicity raise the question of their use in IPM programs in vegetables and the need of new compounds or development of alternative pest control programs.
Asunto(s)
Artrópodos/efectos de los fármacos , Productos Agrícolas/parasitología , Control de Insectos/métodos , Plaguicidas/farmacología , Plaguicidas/toxicidad , Animales , Áfidos/efectos de los fármacos , Áfidos/crecimiento & desarrollo , Artrópodos/crecimiento & desarrollo , Fungicidas Industriales/clasificación , Fungicidas Industriales/farmacología , Fungicidas Industriales/toxicidad , Herbicidas/clasificación , Herbicidas/farmacología , Herbicidas/toxicidad , Insecticidas/clasificación , Insecticidas/farmacología , Insecticidas/toxicidad , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Control Biológico de Vectores/métodos , Plaguicidas/clasificación , Especificidad de la Especie , Pruebas de Toxicidad , Verduras/parasitologíaRESUMEN
Study of factors influencing soil insecticide toxicity are needed to reduce negative impacts of these products on beneficial insects. To date, if high toxicity differences between different type of soils have been reported, there is few specific studies on soil parameters influence on selectivity of soil insecticides to beneficial arthropods. To assess the specific impact of organic matter, the relationship between bio-availability of a soil insecticide, carbosulfan [Sheriff 1 Gr], and its toxicity on a small Carabidae, Bembidion lampros (Herbst.) on a sand enriched with increasing quantities of organic matter was studied. In laboratory, adults of B. lampros were put on different substrate, made of sand or sand with addition of organic matter at 3, 6 and 9% w/w, and treated with carbosulfan applied as granule at the rate of 312.5, 625, 1250 and 6250 microg a.i./m corresponding respectively to 0.5, 1, 2 and 10% of the recommended field rate. Mortalities of B. lampros were assessed after 14 day of exposure. In parallel, the total carbosulfan residue (total extraction) and bioavailable fraction (CaCL2 aqueous extraction) were determined 48h after substrate treatments. According to the mortalities and bio-availability obtained, a dose--response relationship was calculated and compared with a reference relation dose--response obtained on sand, where the bio-availability of the product was considered as 100% of the amount of product applied. Carbosulfan was highly toxic on sand for B. lampros, with 100, 57 and 50% mortality at 10, 2 and 1% of the recommended field rate. When organic matter was added to the sand, the toxicity gradually decreased. This reduction in toxicity was more rapidly observed on sand + organic matter than on pure sand. The mortalities were strongly correlated with the bioavailability, indicating first that the organic matter is fixing an important part of the insecticide and secondly reduce its toxicity to beneficial arthropods. The results suggest that it could be possible, with further research, to predict toxicity of products in the field on different kind of soil according previous laboratory toxicity models and soil analysis. In conclusion, the organic matter influences strongly bio-availability of carbosulfan. This bioavailability was strongly correlated to toxicity to B. lampros. With the improvement of bioavailability determination and method validation, the assessment of pesticide bio-availability in the substrate could help to estimate the pesticide toxicity towards carabidae on different type of soils.
Asunto(s)
Carbamatos/toxicidad , Escarabajos/efectos de los fármacos , Insecticidas/toxicidad , Suelo/análisis , Animales , Disponibilidad Biológica , Carbamatos/farmacología , Escarabajos/crecimiento & desarrollo , Relación Dosis-Respuesta a Droga , Insecticidas/farmacología , Cinética , Residuos de Plaguicidas/análisis , Dióxido de Silicio , Contaminantes del Suelo/farmacología , Contaminantes del Suelo/toxicidad , Factores de TiempoRESUMEN
Regulatory requirements, and in particular phytosanitary quality standards change rapidly. As ACP producers/exporters race to become more competitive, to keep their market share and to satisfay their customers' commercial demands (e.g. EUREP-GAP certification), the need for competent staff who are aware of the company's quality objectives and trained to follow instructions is crucial. Mastering sanitary quality is only possible if matched with a programme to build the skills of companies' human resources. The Pesticide Initiative Programme (PIP), mindful of the importance of making operators autonomous and of training them to monitor EU food safety regulations and technology on their own, has successfully developed a training programme while building a quality network of local/ACP service providers. By building the capacities of ACP experts and then securing their services as trainers, PIP also guarantees companies' access to expertise and the sustainability of their efforts to comply with new EU regulations. The training strategy developed by PIP rests on two pilars: instructor training and collective training. Instructor training consists in reinforcing the technical knowledge of local experts (agronomists, hygienists, etc.) by providing them with active teaching methods. Once the ACP experts have gained enough technical knowledge of the key areas of crop protection--mainly pesticides management--and food safety, and have demonstrated their capacity to train the technical staff of local companies, the PIP has carried out a collective training programme in 2004, 2005 and 2006. To date, more than 130 consultants covering about 15 ACP countries have received instructor training, and more than 700 people have participated in collective and in-company training sessions.
Asunto(s)
Seguridad de Productos para el Consumidor , Productos Agrícolas/química , Productos Agrícolas/normas , Industria de Alimentos , Residuos de Plaguicidas/análisis , Unión Europea , Industria de Alimentos/legislación & jurisprudencia , Industria de Alimentos/normas , Frutas/química , Frutas/normas , Humanos , Legislación Alimentaria , Control de Calidad , Verduras/química , Verduras/normas , Recursos HumanosRESUMEN
The increased concern about environmental effect of off-target deposits of pesticides use has resulted in the development of numerous spray drift models. Statistical models based on experimental field studies are used to estimate off-target deposits for different sprayers in various environmental conditions. Random-walk and computational fluid dynamics (CFD) models have been used to predict the effect of operational parameters and were extensively validated in wind tunnel. A third group, Gaussian dispersion models have been used for several years for the environmental assessment of the pesticide spray drift, mainly for aerial application. When these models were used for the evaluation of boom sprayer spray drift, their predictions were found unreliable in the short range, were the initial release conditions of the droplets have a significant effect on the spray deposits. For longer ranges, the results were found consistent with the field measurements as the characteristics of the source have a reduced influence on the small droplets drift. Three major parameters must be taken into account in order to define realistic initial conditions of the droplets in a spray drift model: the spray pattern of the nozzle, the boom movements and the effect of entrained air and droplet velocities. To take theses parameters into account in a Gaussian model, the nozzle droplet size distribution measured with a PIV setup to divide the nozzle output into several size classes. The spray deposits of each diameter class was computed for each successive position of the nozzle combining the nozzle spray distribution with drift computed with a Gaussian tilting plume model. The summation of these footprints resulted in the global drift of the nozzle. For increasing droplet size, the release height used in the Gaussian model was decreased from nozzle height to ground level using an experimental law to take into account the effect of entrained air and droplet initial velocity. The experimental law was adjusted on 2 m/s wind tunnel measurements and robustness was evaluated for 1 and 4 m/s.
Asunto(s)
Agricultura/instrumentación , Agricultura/métodos , Contaminantes Ambientales/análisis , Plaguicidas/análisis , Viento , Aerosoles , Movimientos del Aire , Monitoreo del Ambiente/métodos , Modelos Teóricos , Distribución Normal , Tamaño de la Partícula , Medición de RiesgoRESUMEN
In order to improve IPM programs in carrot, 7 fungicides, 12 herbicides and 9 insecticides commonly used in Belgium were tested for their toxicity towards five beneficial arthropods representative of most important natural enemies encountered in carrot: parasitic wasps - Aphidius rhopalosiphi (De Stefani-Perez) (Hym., Aphidiidae), ladybirds - Adalia bipunctata (L.) (Col., Coccinellidae), hoverfly - Episyrphus balteatus (Dipt.. Syrphidae), rove beetle - Aleochara bilineata (Col., Staphylinidae) and carabid beetle - Bembidion lampros (Col., Carabidae). Initialy, all plant protection products were tested on inert substrate glass plates or sand according to the insect. Products with a corrected mortality (CM) or a parasitism reduction (PR) lower than 30% were kept for the constitution of positive list (green list). The other compounds were further tested on plant for A. rhopalosiphi, A. bipunctata, E. balteatus and soil for B. lampros and A. bilineata. With these extended laboratory tests results, products were listed in toxicity class: green category [CM or PR < or = 30%], yellow category [30% < CM or PR < or = 60%] and orange category [60% < CM or PR < or = 80%]. Products with toxicity higher than 80% on plants or that reduce parasitism more than 80% on soil were put in red category and are not recommended to Integrated Pest Management programs in carrot. Results showed that all fungicides tested were harmless to beneficials except Tebuconazole, which was slightly harmful for A. bipunctata. Herbicides were also harmless for soil beneficials, except Chlorpropham. This product was very toxic on sand towards A. bilineata and must be tested on soil. All soil insecticides tested were very toxic for ground beneficials and considered as non-selective. Their use in IPM is subject to questioning in view of negative impacts on beneficials. Among foliar insecticides, Dimethoate and Deltamethrin are not recommended for IPM because their high toxicity for all beneficials. The other foliar insecticides were more selective; any of them were harmless for all species tested.
Asunto(s)
Daucus carota/parasitología , Control de Insectos/métodos , Plaguicidas/farmacología , Plaguicidas/toxicidad , Animales , Fungicidas Industriales/clasificación , Fungicidas Industriales/farmacología , Fungicidas Industriales/toxicidad , Herbicidas/clasificación , Herbicidas/farmacología , Herbicidas/toxicidad , Insecticidas/clasificación , Insecticidas/farmacología , Insecticidas/toxicidad , Plaguicidas/clasificación , Especificidad de la Especie , Pruebas de ToxicidadRESUMEN
The aim of this paper is to analyse the effect of adjuvants and formulations on drift. The spray liquids consisted of four adjuvants (Actirob 0.4 %, Tensiofix 0.2%, Breakthru 0.2%, Silwet L-77 0.1%) with water and with two formulations of Phenmediphame (C16H16N2O4, 4.45%): an emulsion-forming (EC) and a suspension concentrate (SC). A standard flat fan nozzle at a pressure of 3 bar was used. The droplet size spectrum of each combination was determined using a Malvern granulometer. The droplet size was characterized by the volume median diameter (VMD) and the percentage of spray volume contained in droplets <100 microm (%<100). The relative drift potential was measured for each combination of formulation and adjuvant in a wind-tunnel. This latter has a working section 2.0 m wide by 2.0 m high by 6.0 m long. The air-stream is drawn by a 1.2 m diameter axial flow fan, powered by a 22 kW electric motor. Wind speed was 5 m/s. Its uniformity was controlled by a three-dimensional sonic anemometer able to move on a linear translation beam placed in the tunnel cross section. The wind-tunnel was operated under ambient conditions and three repetitions were performed randomized in order to eliminate variations in temperature and humidity for each combination. The ground spray deposits were measured on glass fibber collectors using a fluorescent tracer dye (sodium fluorescein), at a concentration of 2.5 mg/l. The statistical analysis of the droplet spectrum showed that the Phenmediphame SC formulation generated droplets of higher size than the EC. The mean VMD values were respectively equal to 228+/-11 microm and 185+/-11 microm for these formulations. For SC formulation, Break-thru decreased the VMD while Tensiofix increased the %<100. This confirmed that the degree to which an adjuvant influences spray characteristics is very variable. The drift profiles produced by the different combinations were similar, but the relative drift potential was significantly different comparing SC and EC formulations: it respectively reached 0.8+/-0,08% and 1.2+/-0,08%, whatever the adjuvant used in the liquid. Clearly, when using a flat fan nozzle to spray Phenmediphame, the droplet size and the drift potential are mainly governed by the kind of formulation, even if an interaction between the formulation and the adjuvant exists.
Asunto(s)
Agricultura , Carbamatos/análisis , Carbamatos/química , Plaguicidas , Viento , Agricultura/instrumentación , Agricultura/métodos , Fenómenos Químicos , Química Física , Emulsiones , Excipientes , Tamaño de la Partícula , Plaguicidas/análisis , Plaguicidas/química , Tensión Superficial , Tensoactivos , ViscosidadRESUMEN
In order to promote IPM programmes in potato, the toxicity of 19 fungicides, 4 herbicides and 11 insecticides commonly used in this crop in Belgium was assessed on three beneficial arthropods. These species were representative of the most important aphid specific natural enemies encountered in potatoes: a parasitic wasp--Aphidius rhopalosiphi (De Stefani-Perez) (Hym., Aphidiidae), a ladybird--Adalia bipunctata (L.) (Col., Coccinellidae) and a hoverfly--Episyrphus balteatus (Dipt., Syrphidae). In a first time, pesticides were tested on glass plates on A. rhopalosiphi adults and A. bipunctata and E. balteatus larvae. For each insect, products inducing corrected mortality (Mc) lower than 30% were directly classified in a positive list for harmless products (green list). The other compounds were further tested on plants and listed in toxicity classes according to mortalities induced during this extended laboratory test: harmless (Mc < 30%), slightly harmful (30% < Mc < 60%), moderately harmful (60% < Mc < 80%) and harmful (Mc > 80). A chemical determination of pesticides residues was also performed for each experiment in order to determine the exposure of beneficial arthropods to pesticide residues and to validate the application of chemicals on tested substrates. On the basis of the results of acute toxicity tests, the period of each pesticide use according to normal agricultural practices and the abundance and importance of the three different groups of aphid natural enemies at different periods of the year, four pesticides lists were built up. Each list corresponded to a different period of pesticides application: Period I--from seedling to beginning of June (based on A. rhopalosiphi tests), Period II--beginning to end of June (based on A. rhopalosiphi tests), Period III beginning to end of July (based on E. balteatus and A. bipunctata tests) and Period IV--August to harvest (no exposure of beneficials). Results showed that herbicides were not toxic to the three species and can be used according to normal agricultural practices without restrictions. All fungicides can also be used without restrictions at recommended rates. Only the mixture Metalaxyl-M + Fluazinam was slightly harmful to A. bipunctata but had no effects on A. rhopalosiphi and E. balteatus. Results were more contrasted for insecticides and none of them was totally selective for all the 3 beneficial arthropods. Therefore, they can only be used with restrictions at periods II and III, according to the beneficial species that need to be protected.