Resistant Pest Management Newsletter

Mobile Inspection and Diagnosis Service of Sprayers in Resistance Prevention
Results Obtained Out of Inspections Performed by a Group of Producers During the 2004-2005 Season

INTRODUCTION Misaplication of pesticides is a serious problem in Agriculture. Poorly calibrated sprayers result in over-dosing or under-dosing of pesticides. Both situations are undesirable, because of environmental and commercial reasons for the former and poor control and resistance development concerns for the latter. Continuous under-dosing in a control program can exacerbate resistance problems. Our commercial and professional activity related both to pest control and the appropriate use of pesticides has enabled us, from the very start, to obtain and evaluate suggestions from a growing number of producers who have shown to be very interested in both improving and optimizing the whole process related to those two subjects. Producers are especially interested in learning about sprayers and in the techniques applied in their handling.

Aspects like reducing the volume of water used and minimizing the damages brought about both by overdosing and under-dosing, the use of new products with extremely reduced doses, the need to cut down damage risks in adyacent fields, etc.. All these aspects are related to the need to control the equipment carefully before use and to perform a close regulation and calibration of all devices. This has enabled us to visualize a demand for a fully specialized kind of service. Such a service must be carried out by highly specialized technicians who must be able both to diagnose and give solution to a countless number of failures and defects which are usual in spraying equipments. These technicians must also be able to solve problems on the spot, where the sprayer is at work and at the time required. As a result, we have decided to devise and put into practice a specific inspection service of each component of the spray hydraulic system as well as of the part that contributes to put the system at work both efficiently and safely. The aims are: to evaluate the work done by each component of the equipment, to diagnose its corresponding state and to solve any problems immediately and on the spot.

In order to develop this project, we have done some research so as to collect information which would contribute to optimize the service from various experiences of technical inspections in use, especially from European countries. We have also got some information from some articles issued by authors such as Santiago Plana de Martí (1999), Daniel Vannuci and Marcelo Biocca (1999) and Jozef Sawa (1999). Through a careful analysis and studies carried out abroad, we can pick up three basic aims to follow up in the inspection of sprayers in use. They are as follows:

a. Increase farmers' profitability: By identifying and repairing sprayers' failures he can carry out more efficient tasks, cutting down risks of over-dosing.

b. Reduce under-dosing: Increase pesticide use efficiency by ensuring the right dose application, reducing the risk of lack of control and resistance development.

c. Maximize workers' safety: By identifying possible causes of intoxication, poissoning or accidents.

d. Cut down pollution: By avoiding deficient distribution of pesticides and eventual contamination.

Our company started providing this service in 1999 by focusing attention on the Province of Córdoba, Argentina. We have provided our service to highly technically developed producers who are quite ready to adopt new technologies in their activities. At present, inspections and diagnosis work are being carried out in most areas with extensive crops in our country. This task is conducted by the previously mentioned producers.

MATERIALS AND METHODS The service is performed where the sprayer is at work. For this purpose, a utility van equipped with special instruments is used. Besides, accessories and parts of the sprayer are carried to solve any emerging problem in the machine. The technical instruments mounted on the van are the following: - Nozzle testing bench, Gauge inspection bench, Electronic flow-meters, Digital tachometer, Manometers, Electronic tester, GPS, Gauge computer, 50 m measuring tape, Graduated bars, Stakes, and Various tools. It is important to emphasize that the technical instruments used need to have the utmost grade of accuracy due to the kind of controls to be made. For this reason, the standards with which our instruments are permanently measured, are also examined and certified periodically by a certifying organization. In order to achieve the aims mentioned above, some procedures and directives have been developed in ISO 9000 Norm formats. They are based on worldwide European normatives because they are widely spread and highly accepted. These technically based normatives are meant to be the foundations of our procedures. They are as follows:

Inspection and diagnosis of the state and operation of each sprayer component such as: tank, accessory tanks, agrochemical charger, pump, flybacks, mixers, manual and electrical controls, cut off locks, pressure regulators, manometers, flow gauge, computers, filters, hoses, nozzles, disks, etc., are carried out by following instructions and procedures developed according to international requirements and normatives using the above mentioned instruments. To avoid workers' accidents we also verify the presence of personal protection equipment such as masks, gloves, helmets, boots, overalls and the protection of the power takeoff, of the drive belts, the signal protection, etc.. Once the inspection is finished, the certification is either given or not according to the state of equipments' final diagnosis.

ACHIEVED RESULTS The inspections made during 2004-2005 were applied to a segment of producers characterized by working in wide areas and the intensively use of the sprayer. The following data are obtained from the total inspections. The achieved results are as follows: Table 1, Table 2, Table 3.

The information of the inspected elements and components of each sprayer is presented in the two following charts. In figure 1, we can see the result of the elements' inspection related to the workers' security. At first side, we can infer the lack of conscience of the serious risk that the group of workers' work involves. In these inspections, we could verify that the workers do not wear helmets in 97% of the sprayers; 61% do not wear gloves; 39% work without masks, and 67% do not wear overalls.

In figure 2, we can see the state of the sprayer's components which directly affect the quality of pesticides controls carried out. The details provide what happens in Argentina with the use of pesticides, treatment cost, outcome losses, etc.

The results shown in the previous chart enable us to notice five essential problems as seen from application quality. Because of their incidence upon the desired results they should be both analyzed and corrected as soon as possible. The problems are the following: Agitators, Boom's condition and stability, Worn-out nozzles, Hydrical balance, Manometers and sensors. The solution to these problems will depend on owner's decision regarding investment on professional specialization and sprayer maintenance and repair. The results shown here indicate that most of the sprayers analyzed cannot provide an appropriate operation. It is important for those providing this type of service to emphasize the environmental and commercial importance of having a properly calibrated sprayer to optimize control and reduce the chances of pesticide resistant pest development due to under-dosing.

ACKNOWLEDGEMENTS The author wants to thank Dr. Pablo Kálnay for his collaboration with this article.

REFERENCES

S LANGENAKENS, J., BRAEKMAN, P. The Mandatory Inspection of Sprayers in Belgium: History, Organization, Criteria and Results. En II Simposio Internacional de Tecnología de Aplicacao de Agrotoxicos: Eficiencia, Economia, e Preservacao da Saúde Humana e do Ambiente. 2001.

KOCH, H. German Certification Systems of New Sprayers and Tose Already in Use. En II Simposio Internacional de Tecnología de Aplicacao de Agrotoxicos: Eficiencia, Economia, e Preservacao da Saúde Humana e do Ambiente. 2001.

ANTUNIASSI, U. R., GANDOLFO, M. A. Projeto IPP - Inspecao de Pulverizadores. En II Simposio Internacional de Tecnología de Aplicacao de Agrotoxicos: Eficiencia, Economia, e Preservacao da Saúde Humana e do Ambiente. 2001.

VANNUCCI, D., BIOCCA, M. Controllo Dell'Eficienza Distributiva delle Macchine per la Distribuzione dei Fitofarmaci. 1999.

PLANAS DE MARTI, S., GRACIA AGUILA, F. Inspección de Máquinas de Tratamientos Fitosanitarios. Vida Rural. 01/03/1998.

PLANAS DE MARTI, S., GRACIA AGUILA, F. Características Técnicas de los Pulverizadores Agrícolas en España. Vida Rural. 15/02/1999.