Weeds
Grasses
Sedges
Broadleaf
Diseases
Fungal
Bacterial
Viral
Agro-ecology
Cowpea, mungbean, corn, bell pepper, garlic, onion, soybean, etc, serve as important homes of natural enemies during the non-rice season. Non-rice crop fields which form a pattern within the rice blocks are good for conserving
natural enemies. In a
monoculture situation, staggered planting provides a better conservation of natural enemies than does strictly
synchronous planting.
Fish culture in rice fields reduces the use of pesticides and fertilizer. Common carp, catfish, and tilapia are fish species commonly raised in rice fields. Fishes are able to reduce populations of rice leafhoppers and rice leaf rollers 26 times as well as rice planthoppers and the yellow stem borer. Some fishes feed on planthopper and leafhopper eggs on the outer leaf surface of the plant. Aside from controlling pests and maintaining soil fertility, the control of weeds and diseases is another ecological benefit of rice-fish culture.
The use of ducks for pest control is a common practice in China and Vietnam. Ducks feed on the stem borer, leaf folders, grasshoppers, plant hoppers, leafhoppers, and other rice pests. A duck can consume 100 pests an hour and can rapidly decrease pests population quickly particularly in the early to mid-tillering stage.
Black drongos, commonly found in the rice environments of South Asia, are insectivorous birds that prey on rice pests. Placing bamboo or wooden perches in rice fields can attract these insect-predatory birds. These perches serve as watchtowers and resting places for these birds during the hunting stage.
Further information
IRRI has developed golden indica rice that is suitable for planting in a tropical Asian environment. This is a variety (Japonica rice cultivar, T309) with beta-carotene and enhanced iron to reduce malnutrition and premature death prevalent among children in developing countries. However, many more months of research are required before it finally becomes available in the local markets; it has to be tested on the basis of palatability, resistance to pests and diseases, and validity of answers to queries regarding food safety.
Australian scientists are developing drought-resistant rice for the benefit of farmers in Cambodia, Laos, and Thailand. These regions do not have irrigation water to grow rice; about 70% of their rice fields simply rely on rainfall. The University of Queensland is in the process of identifying the genes that will make rice plants resistant to droughts. Once the genes are identified, researchers can start using molecular tools to improve the efficiency of developing rice plants.
External links
References
- IRRI & Queensland University. (2001): Rice IPM. An interactive information and identification system for integrated pest management in rice. University of Queensland and IRRI.
- IRRI. (2004): Rice integrated pest management. http://www.knowledgebank.irri.org/pu_ipm.htm
- Reissig, W.; Heinrichs, E.; Litsinger, J.; Moody, K.; Fiedler, L.; Mew, T.; Barrion, A. (1986): Illustrated guide to integrated pest management in rice in tropical Asia. IRRI. Los Banos, Laguna, Philippines.