The Basics of Pest Ecology

Understanding the basic ecological processes of pest. An unwanted organism which competes with people for food and shelter, or threatens their health, comfort, or welfare. populations is important in assessing the damage they cause and in designing appropriate measures for managing them.  [Here, a pest organism is defined as any noxious organism that causes damage to a rice crop and results in lost yield and/or quality. These pests range from chewing and sucking insects, plant diseases and weeds to snails, rats Rodents of the genus Rattus and other allied genera distinguished from mice by their larger size and difference in teeth and other structures. and nematodes.]

The threat posed by any pest population will depend on its size and time of attack and the crop loss it is likely to cause. This threat will also depend on the major ecological features of the pest population. Some pests remain in the field from rice crop to rice crop, whereas others migrate or are physically carried by air or water into the rice field. Some pests can increase very rapidly under favourable conditions and cause outbreaks, whereas others, with slower growth rates, may also cause damage.

The rate The amount of active ingredient of a pesticide applied to a unit area. of growth of a pest population during the life of a crop depends on four factors:

• Host-plant resistance
• Climatic favourability
• Natural control mechanismsManagement practices