Biological Control By Farmer Insectaries

 

By Jan Dietrick and Everett J. (Deke) Dietrick, CPE, Rincon- Vitova Insectaries

 

Biological control by natural enemies is the only permanent, low-cost way to control insect pests. Combined with safety and environmental concerns and the documentation of hundreds of species now resistant to pesticides,. producers and consumers are getting smart about biological control. Despite the potential for solving pest problems biologically, funding is not being allocated to develop and promote reliable biological programs. Leadership in the way of funding from grower organizations is the most logical trend. Farmers specializing in specific crops in particular areas can benefit by spreading costs among themselves. The Fillmore Citrus Protective District is a well-known example of the farmer-financed insectary. Growers organized in the late 1930's to build their insectary to grow the black scale parasite, Metaphycus helvolus (Compere) for control of Saissettia oleae (Oliver). In 1961, the Fillmore Insectary started growing the "Golden Chalcid" Aphytis melinus DeBach, for control of California red scale.Augmentative releases of these beneficials has been the basis of its very successful pest management programs. Reliance on biological control has led to control of ten species of insects that are major pests of citrus in other districts. Limited pesticide treatments, such as for ant control, are made in ways that conserve natural enemy complexes associated with all pests of citrus. Thus a large group of farmers with total of 9,400 acres has kept average pesticide treatments below one application per acre per year for over 50 years. One might ask why the existing commercial insectaries are not producing more new and varied biological controls on contract or for sale. If you think about it, the vast array of natural enemy complexes are not being marketed, because there is not enough demand. Needs are often very specific and within limited time frames. Losses from variable weather patterns affecting the window for releases, shipping and now the growing administrative costs of compliance with regulatory agencies over the transport of biological organisms not to mention the capital, supply and human resource development costs associated with developing a new mass-rearing system result in little if any profitability. When you consider that after all of this investment, the organism is not-patentable and belongs to anybody who wants to buy it and piggyback on the original producers developmental efforts, it is no wonder that new organisms are not arriving in the marketplace the farmers would like.Farmer insectaries avoid many costs of commercial. insectaries. They give preferred service in timing releases. Specific strains most appropriate to the geographic region are produced. There are no marketing and distribution Costs. Combining insectary beneficials with monitoring by affiliated entomologists to maximize indigenous natural enemy complexes allows for maximum flexibility and minimum losses.In addition to the mass-rearing and monitoring resources that the growers can fund cooperatively, classical biological projects can also be organized most cost-effectively by cooperatives with technical assistance from universities. Governments and universities are not obtaining the needed funds to conduct these essential projects to meet demands of increasing numbers of exotic pests being spread around the world by travel and commerce. Even when governmentdoes acquire the money to research and import an exotic beneficial, there is never enough money to mass-produce and distribute them. The implementation of biological control on farms is up to individual growers working together. The small farmer-financed insectary can fulfill this need.

 

An example of how this might work would be with the classical biological control "biotype" obtained of the egg parasite Anagrus epos that attacks the variegated leafhopper. These parasites have been imported and colonized successfully by the University of California biological control specialists. Numerous releases have been made experimentally, but there is no money for wide distribution of these new parasites. If farmers wait for them to spread throughout the range of the host, it may take years.

 

A grower-owned insectary could easily obtain and produce this parasite and spread it among its members right away. Thus, biological control of this key pest can be achieved in a few years instead of a decade or more.Organizing- farmer-owned biological control insectaries is not a subject taught in agricultural schools in the U.S., nor is it effectively promoted by the agricultural extension services. Considerable effort and money is spent on monitoring pests and on propaganda describing pests and pesticides, but our educational and advisory institutions have ignored the development of informational materials and training in skills of insectary development and management, beneficial insect production systems and in how to best use beneficials in various production settings.

 

Although it is difficult to join together the several forces that are needed to begin such cooperative efforts, the time is right and the results promise to be long-lasting with increased profits going where they belong.., to the farmers. The technology is known and there are under-employed advocates trained in the science of biological control who would welcome the chance to practice under the leadership and financing of grower organizations.