Kenya is a water deficit country and there is need to use the available little water as efficiently as possible. There are considerable losses of water not only along the irrigation canals but also through evaporation, percolation and drainage among others. It is therefore important to synchronize water availability during critical peak plant water requirements period to maximize output in rice. Rice requires more water during crop establishment and tillering to increase number of tillers hence productive tillers, reproductive and ripening phases starting from Panicle Initiation (PI) to dough stages.
In Kenya, there are three major types of rice production ecologies whose water requirements are different; irrigated, rainfed lowlands and rainfed upland ecologies.
Irrigated rice production ecologiesWater is important under irrigated production ecologies as it boosts grain yield of rice. Irrigated rice requires varied levels of water depending on crop growth and development. Water is therefore required up to 10 cm high for puddling stage before being reduced at transplanting to 3 – 5 cm depending on seedling height. At this early stage of seedling establishment high water level reduces chances of wilting. It is recommended that water is drained 21 days after transplanting to ensure efficient fertilizer application (1st top-dress), weed and insect pest and disease control, where applicable. Reduction of water depths during tillering also encourages tillering and mid-term drainage of water is essential just before PI.
After dough stage water levels could be gradually reduced to hasten ripening and maturation. No water should be left standing in the fields 7 - 10 days before harvesting and to facilitate easy handling. Water management is one of the most important technologies in encouraging rice growth and controlling weeds.
Rainfed Lowland Ecologies
2.0 Sound Water Management for upland rice
Synchronize peak water regimes with crop establishment, reproductive and ripening phases
3.0. Coping with water scarcity
Supplemental irrigation, planting at the onset of rains in western and Coastal regions.
4.0. e –water management.
Synchronize water application based on crop water requirement