Pest and disease control

Organic systems seek to have a more measured pace of crop growth which encourages a more robust plant to resist pests and diseases. The greater balance of biodiversity achieves a more natural level of pest predators and a non-stressed crop is more likely to resist disease. Unless specifically targeted, some pesticides will kill beneficial as well as pest insects. 

Pesticides approved for organic production also have to comply with the PSD requirements. However, it must be stressed that the use of any plant protection product on an organic crop is seen very much as being a matter of last resort. Growers need to seek derogations for their use from their certification body. The EU is currently undergoing a complete review of all pesticide approvals and there is a strong likelihood that substances such as copper and sulphur will be dropped from the approvals list in future. 

Some concern has been raised over the lack of harmonisation of the approved pesticides in organic standards between different states. There are some plant protection products available to organic growers in Holland and France which cannot be used in the UK. Clearly this is disadvantageous to British growers and should be resolved at the earliest opportunity by the Commission. 

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Pest and Disease Controls. Chapter in Technology and Western Civilization, vol. II, Melvin Kranzberg and Carroll W. Pursell, Jr., eds., Oxford University Press, New York, 1967, pp. 369-85. 

This is the practice of growing related vegetables in different areas of the garden in consecutive years. If crops from the same family—the lettuce family, the brassica family, and so on (see pp.234-253)—are grown in the same place year after year, related soilborne pests and diseases may become established. In small plots, moving vegetables just a few yards may not have much effect on pest and disease control, but it is still worth doing for other benefits. 

Unger and McCalla have pointed out factors (21) which could contribute to the observed yield reductions including lack of proper expertise and equipment to manage surface residues, lack of pest and disease control, inadequate nutrient availability, particularly nitrogen, major alterations in biological properties of soil, and production of phytotoxic chemicals. 

Lack of knowledge on improving soil fertility, pest and disease control... 

Many of the amendments have been prompted as a result of practical experience and continuing discussion between member states. The increased definition of the composition and conditions of use of soil amendments and pest and disease control products forming Annex II is a good example of the increasing level of detail that the Regulation has embraced. It is well known that the initial intention of the Commission when commencing the development of the Regulation was a fairly basic statement of the need to avoid the use of synthetic chemicals. It soon became clear that much more detailed rules would be required. 

General Field histories Crop Inputs, e.g. fertilisers, farm yard manure, pesticides Crop and forage production Rotations Manure and fertiliser management, including sources, treatments, rates and dates of applications Seed treatments Pest and disease-control measures... 

Scopes, N. and Stables, L. (1989) Pest and Disease Control Handbook. (3rd edn) BCPC. 

Key words principles of organic farming, weed, pest and disease control on organic farms, organic farming and the enviromnent, organic winter wheat, organic potato production. 

In the first edition there was nothing on pesticide resistance. There had been a few cases of resistance to the oiganochlorine insecticides but it was not considered an important issue. Now, with 40 plus years of routine use of pesticides, resistance is a common problem in many groups of agrochemicals. It is partly because of resistance issues and the limited production of new chemicals that maity farmers have had to take a more integrated approach to weed, pest and disease control, so a specific chapter was added in the 8th edition. 

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