Application of nematicides via drip irrigation.

Use of drip, or trickle, irrigation in agriculture has increased rapidly during the past 20 years. In 1970 approximately 50,000 ha in the United States were under drip irrigation, by 1985 the area had increased to over 300,000 ha (6). Irrigation has been used to deliver fertilizers and pesticides (8,9,14,18,27,28), and there are increasing numbers of studies on the application of nematicidal compounds or other pest control agents via drip irrigation (15,12,13,16,19,20,22,24,25,32). Most of these reports, however, do not detail the mechanical considerations of delivering nematicides through drip irrigation. In the following we discuss application of nematicides through drip irrigation, ment ioning potential problems and considerations that are important for successful application. We focus on the use of drip irrigation for delivery of nematicides in research, and refer to our research experience with nematicides delivered by drip irrigation systems in Hawaiian pineapple. The technical (soil physics and engineering) aspects of drip irrigation are not discussed here, as reviews on these topics are available (6,8,9,21,29). Concepts and history: Drip or trickle irrigation delivers relatively low volumes of