Expected Benefits from Nonchemical Methods of Alfalfa Weevil Control

Abstract

The problem of managing insect pests has been receiving increased interest as a part of the technological revolution that has dramatically increased agricultural output.' During the past few decades, several biological and cultural methods of pest control have been conceived and/or implemented, e.g., DeBach, Huffaker (1971, 1980), Huffaker and Messenger, Metcalf and Luckmann, Reichelderfer and Bender. However, contemporary technology has analyzed and relied heavily on the use of synthetic chemical pesticides (Hall and Norgaard; Regev Gutierrez, Feder; Talpaz and Borosh; Talpaz et al.). The preference for chemical control is derived, in most cases, from its achievement of satisfactory control at relatively low costs. However, the intensive, as well as extensive, uses of synthetic organic pesticides, in particular a few persistant insecticides such as DDT and BHC, have had detrimental effects on the quality of the environment. Prolific use of chemical pesticides develops genetic pest resistance, changes pest complexes by affecting nontarget populations and allowing outbreaks of secondary pests, and affects the ecosystem with its residues in feeds, foods, and organisms (Shoemaker). Policymakers have reflected the concern of society for environmental contamination by legislation restricting pesticides, suggesting that future pest control cannot solely depend upon routine applications of insecticides. This note investigates the potential gains that may be derived from the use of biological means of control as well as the introduction of a host plant with added resistance (antibiosis) against the alfalfa weevil (Hypera postica). This insect contitutes one of the more important insect pests of alfalfa and can cause large losses in yield or even death of the crop if uncontrolled (Armbrust and Gyrisco). Model Description and Procedure