Pest control, organic methods

Owing to the prohibition of chemosynthetic pesticides under organic farming standards, there is a greatly reduced availability of intervention/treatment-based methods for disease and pest control in organic fruit production systems. The efficacy of the permitted biological control, extract or mineral element (e.g. S and Cu)-based crop protection products is also usually lower than of chemosynthetic pesticides. Permitted plant protection products show efficacies of between 60 and 80% while chemosynthetic fungicides and pesticides often have efficacy levels >95% (Tamm et al., 2004). 

I hope to convince Anne that there are some potential benefits of GE, so I decide to fire away with my most powerful ammunition. There are some pests that cannot be consistently controlled using organic methods. Most ears of organically grown sweet corn carry fat cannibalistic worms and their frass. Wouldn t you rather eat GE corn carrying trace amounts of Bt toxin than eat corn carrying such surprises ... 

Organic agriculture is a know-how-intensive farming method. To be competitive, organic farmers need to experiment with new techniques, and must manage land, labour, capital and innovations quite differently from conventional farmers. How can research and development improve access for small farmers to this know-how and to specific inputs, such as seeds and biological methods of pest control ... 

Note that many of these pest-control practices are important components of a system known as integrated pest management. However, in that system pesticides are often used as a last resort, when other methods do not work effectively enough. In organic agriculture, pesticides are not used (other than the natural ones just referred to). 

Another example of organic synthesis via cross-metathesis is the synthesis of biologically active compounds such as insect pheromones. Use of such pheromones offers an effective and selective pest control method. Thus, cross-metathesis of ethyl oleate with 5-decene results in a cis-trans mixture of ethyl 9-tetradecenoate, an insect pheromone precursor [15]. Cross-metathesis of methyl d.y-5-eicosenoate (obtained from meadowfoam oil) with excess 5-decene gives methyl tm 5-decenoate, which can be transformed into a 83 17 mixture of trani -5-decenylacetate and tran.y-5-decenol (in total 90% trans), the sex pheromone of the Peach Twig Borer moth, a major pest in Northern Hemisphere fruit orchards. The isomeric mixture was active in mating disruption [16]. Other examples of organic synthesis via cross-metathesis are summarised elsewhere [17 18]. 

Langer, V. (1995). Pests and diseases in organically grown vegetables in Denmark A survey of problems and use of control methods , Biological Agriculture and Horticulture, 12 (2) 151-171. 

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