Submitted to: National Research and Action Plan for Silver Leaf Whitefly
Publication Type: Abstract Only
Publication Acceptance Date: February 15, 1998
Publication Date: N/A
Technical Abstract: Although the Silverleaf Whitefly (SLWF) is extremely polyphagous, there are resistant genotypes within the major crops. The host-plant resistance approach has many advantages, but there are disadvantages, including the potential that resistance will "break down" under high insect pressure. This possibility alone has led some to call into question the wisdom of pursuing the plant resistance approach for this pest species. Although th extreme polyphagy of this pest will make management of resistant cultivars difficult, it is likely that resistant germplasm can be deployed and sustained with a reasonable amount of managerial input. Because whitefly injury is expressed in distinct ways, there are independent mechanisms of plant resistance to counter them. Mechanisms for reducing direct feeding damage are directed at preventing SLWF populations from reaching epidemic proportions, and typically utilize antibiosis and antixenosis factors. Strategies for resistance against viruses or physiological plant disorders typically are different and independent from those aimed at reducing direct feeding damage. Many abiotic and biotic factors affect how a resistant cultivar will respond once it is planted in the field. Deployment strategies for pest-resistant cultivars should rely on theories developed for management of insecticide resistance, sustainability of transgenic insecticidal cultivars, and maintenance of conventional pest-resistant cultivars. Management of whitefly resistant resources depends on an understanding of the agronomic system and integration of this technology into a complete management system for this pest. We must be willing to put forth the managerial efforts necessary to sustain the usefulness of our resistant resources.