This research was designed and conducted through partnerships with national agricultural scientists. The primary objective was to listen to farmers and understand the various factors that constrain pest management decisions and practices on-farm.

As a result of the green revolution, the use of yield-increasing inputs such as fer tilizer and pesticides became a matter of course in irrigated rice farming in Southeast Asia. Pesticides were applied liberally, both as a guarantee against crop failure and as a means of fully utilizing the existing yield potential of the crops. However, since outbreaks of pests, such as the brown planthopper (BPH) or the tungro virus, continued to occur despite the application of chemicals, a change of approach began to take place. It is now being realized more and more in Southeast Asia that crop protection problems cannot be resolved solely by the application of chemicals. In the past several years, increasing efforts have there fore been made to introduce, as a first step, supervised crop protection, leading gradually to integrated pest management (Kranz, 1982). Although the crop protection problems naturally differ in the different devel oping countries in Southeast Asia, the economic situation prevailing in these countries can nevertheless be regarded as an important common determinant: pesticide imports use up scarce foreign currency and thus compete with other imports essential to development. For the individual rice farmer, the problem is basically the same: his cash funds are limited and he must carefully weigh whether to use them for purchas ing pesticides, fertilizer or certified seed. In view of this constraint, it is becom ing necessary to abandon the purely prophylactic, routine calendar spraying and instead, employ critically timed and need-based pesticide applications.

Crop loss assessment: background, rationale, and concepts; Component technology for crop loss assessment; Applications of pest and loss assessment technology to pest management.

Rice plant structure and growth stages. Insect pests of rice. Soil pests. Pests at the vegetative stage. Pests at the reproductive. Rice diseases. Weed pestes of rice. Identification and ecology of common weeds in rice. Methods of wees control. Biology and management of riceland rats in Southeast Asia. Management in Southeast Asia. Cultural control. Resistant rice varieties. Diseases races and insect biotypes. Biological control of rice insect pests. Parasistas. Predators. Pesticides. Integration of control meanures for all rice pests. Implementation of integrated pest management strategies.

The four-day international Conference on Pest Management in Rice, which is the subject of this volume, was the third in an ongoing series of meetings on tropical crops organised by the Pesticides Group of the Society of Chemical Industry, London. The participants came from both the public and private sectors and from many different countries. All the major groups of pests-weeds, microorganisms, arthropods and rodents-were considered, as the organisers believe that it is necessary to address the total pest management problems in each particular growing area, and the variety of the papers indicates the importance of a multi disciplinary approach to their solution. Rice is one of the most important world crops and is the major source of food for around 60% of the world's population, with a world production of 500 million tonnes from 150 million hectares of land. Since world stocks amount to only two months supply, many people are at risk from famine. Moreover, it has been esti mated that the world requirement in 2020 will be about 760 million tonnes, an increase of 50%. This pressure of population on food makes efficient pest management vital and is the reason for bringing together experts from all over the world to this major conference.