|PALUMBO, J - University Of California
Submitted to: Pest Management Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/2/2009
Publication Date: 10/19/2009
Citation: 2009. IPM for fresh-market lettuce production in the desert southwest: the produce paradox.. Pest Management Science.
Interpretive Summary: In the 1959 article ‘The Integrated Control Concept’ by V. M. Stern and colleagues, the authors pointed out certain situations that might preclude implementing the principles of integrated control that they developed in their article and that eventually became the foundation of IPM. One of these situations is where economic thresholds are set so low as to make reliance on biological control impractical from a market perspective. For example, consumers have an expectation that fresh market fruits and vegetables should be blemish-free, as though insect pests did not exist. Anything that alters the aesthetic appearance of fresh produce risks lowering the price the consumer will pay. Hence, produce growers are loathe to risk having their crop undervalued due to insect damage or potentially rejected altogether. However, the consumer also expects pesticide-free produce and is often disturbed by reports of excessive pesticide use in agriculture. This, then, is the produce paradox: two values, i.e. the desire for insect-free and pesticide-free produce that are diametrically opposed to one another in situations where even light pest pressure occurs. Despite these constraints, this paper discusses the influence that the integrated control concept has had on the adoption of pest management in desert lettuce crops.
Technical Abstract: In the ‘Integrated Control Concept’, Stern et al. emphasized that, although insecticides are necessary for agricultural production, they should only be used as a last resort and as a complement to biological control. They argued that selective insecticide use should only be attempted after it has been determined that insect control with naturally occurring biotic agents is not capable of preventing economic damage. However, they concluded their seminal paper by emphasizing that integrated control will not work where natural enemies are inadequate or where economic thresholds are too low to rely on biological control. Thus, it is no surprise that insect control in high-value, fresh-market lettuce crops grown in the desert southwest have relied almost exclusively on insecticides to control a complex of mobile, polyphagous pests. Because lettuce and leafy greens are short-season annual crops with little or no tolerance for insect damage or contamination, biological control is generally considered unacceptable. High expectations from consumers for aesthetically appealing produce free of pesticide residues further forces vegetable growers to use chemical control tactics that are not only effective but safe. Consequently, scientists have been developing integrated pest management (IPM) programs for lettuce that are aimed at reducing the economic, occupational and dietary risks associated with chemical controls of the past. Most of these programs have drawn upon the integrated control concept and promote the importance of understanding the agroecosystem, and the need to sample for pest status and use action thresholds for cost-effective insect control. More recently, pest management programs have implemented newly developed, reduced-risk chemistries that are selectively efficacious against key pests. This paper discusses the influence that the integrated control concept, relative to zero-tolerance market standards and other constraints, has had on the adoption of pest management in desert lettuce crops.