01 January
31 December 2006

Service d’aide à la décision sur les ravageurs en céréales

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Cereal pestdecision support system


Integrated pest management is still very much a theoretical concept in arable crops. Even if the bases of management exist, few farmers seriously try to assess pest risks in order to design a crop protection system. Management of insecticide treatment is in many cases still in its infancy, with treatments being all too often guided by worry rather than reason. This is totally at odds with society’s expectations nowadays, especially since the resources do exist. If properly applied, knowledge gained about pests and pesticides enables crops to be protected in a way that combines efficiency, cost-effectiveness and environmental compatibility. Rather than expecting farmers to bear the full burden of the progress to which society aspires, by imposing ever-greater constraints upon them and constantly reminding them to strive for quality, cut down on inputs and be kind to the environment, this initiative aims primarily to help farmers. In the medium term, the educational impact of the undertaking ought also to make itself felt, leading to a better understanding of the problems caused by pests and more efficient use of the means of control available.

Description of tasks

Principle and operation Scientific leadership and research support are provided by the Walloon agricultural Research centre, in the form of : · Annual drafting of a technical specification describing in detail the undertaking and individual roles within it, including improvements. · Training and technical support for participants. · Drafting of recommendations. · Validation of the system by setting up tests in which the recommendations made are tested against alternative proposals, notably from the industry. Only observations made each year by the same technicians in reference fields distributed throughout the area are taken into consideration. Unlike other systems, the aim is not to provide each farmer with customised advice, but rather to tell him what is happening in similar areas in terms of geographical location and crops grown, and what is likely to happen on his farm as well. Only the commonest situations are thus covered, but regular information of guaranteed quality is provided. Recommendations are sent out within hours of observation in the field, by fax, automatic telephone answering machine, e?mail and via the farming press. Compared to direct use by farmers of ready-made models, this approach has the advantage of describing the situation as it is observed, drawing attention to any special features and above all, interpreting what is happening. Rather than a basic decision support tool including only predictable elements and supplying set proposals on that basis, the aim is to provide a thinking support tool by first of all providing the elements and explaining the logic before then, and only then, proposing action. A system of this kind, where the decision support is based on regional observations, may seem crude. However, unlike protected crops and perennial crops, where each plot retains a memory of the past in terms of population levels and types of pests and auxiliary organisms encountered, annual crops within a region start developing with more or less homogeneous data from one plot to another. The system of observation of a sample of reference plots is thus feasible. Operating a system of observations and warnings creates a sizeable workload, but the presence of entomologists in the field allows continuous monitoring of crops and ensures a rapid response to unexpected developments such as the occurrence of unusual numbers of less common pests. Main pests monitored Aphids carrying yellow dwarf virus A network of around twenty observation fields throughout the Walloon Region is established each year. Aphid counts and virological analysis of a sample indicate the extent of the epidemic in each field and allow the expediency of treatment to be assessed. The first recommendations are made in late September and carry on through to April. Wheat bulb fly: Delia coarctata FALL Oviposition levels are measured in late summer at the same hundred reference sites every year. This provides a basis for assessing the risk level compared to previous years with respect not to individual fields but a whole region. The recommendations made at the beginning of September enable cereal growers to decide to treat the seed, this being the only reliable remedy against this insect. Aphids and other summer wheat pests A variety of aphid infestation prediction models have been constructed over the last thirty years but despite extensive research, none of them is completely reliable, in view of the complexity of interactions between aphid infestation factors. Also, other pests hitherto regarded as “secondary” are often present in the crop at that time of year and are responsible for some loss of yield, in particular the cereal chrysomelid Oulema melanopa and the orange wheat blossom midge Sitodiplosis mosellana. Observations in a network of around twenty fields are aimed at describing the situation in the fields in real time and, as in the case of yellow dwarf virus, providing short-term forecasts of the likely trend. Common-sense advice aimed at avoiding the most obvious errors in identification or assessing occurrences is also offered. Slugs and rodents When occasional infestations of slugs or voles occur, advice on controlling these pests may also be included in the recommendations, on the basis of observations in the field.


Observations in the field are made by DGA-Development, CARAH, CHPTE, the Agricultural University (FUSAGx) and CRA-W. Virological analyses and soil analyses (wheat bulb fly) are the responsibility of the CRA-W laboratories, as is formal identification of aphids and other pests. This project is being run on behalf of CADCO (Centre agricole pour le développement des céréales et des oléo-protéagineux / Cereal and oil seed plant development centre). The coordinator, Xavier Bertel, is in charge of issuing recommendations.


  • CADCO - Agricultural Centre for the Development of Cereals and Seed crop
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