RICE RATOONING - IRRI books - International Rice Research Institute

Rice ratooning as an alternativeto double cropping in tropical AsiaK. KrishnamurthyDirector of Research, University of Agricultural Sciences, GKVK Campus,Bangalore 560 065, IndiaRice is cultivated in tropical Asia (South and Southeast Asia) over an area of about88.7 million ha, with an annual total production of nearly 183.8 million tons ofrough rice, an average productivity of 2.7 t/ha (Table 1). Only 14% of the rice area intropical Asia supports 2 crops of rice per year under irrigation. The remainingriceland is entirely rainfed, with varying water regimes.AREA OF SUITABILITYIn areas where adequate water is available after the main crop season, rice ratooningcould be practiced as an alternative to double-cropping. It is particularly suited toareas where monocropping is practiced and resources go to waste in the off-season,because no crops other than rice can be grown under the climate and moisturelimitations.Such situations exist widely in hills and valleys in the tropical heavy-rainfallmountainous regions of the world.ADVANTAGES OF RICE RATOONINGRice ratooning is not a new practice with farmers. Its usefulness has been studied inmany countries such as India, Japan, USA, Philippines, Brazil, Colombia,Swaziland, Thailand, and Taiwan. However, only in Texas, USA, is it practiced on acommercial scale on 50% of the rice area. The advantage of rice ratooning is that inareas where rice is the main crop, a double crop of rice can be grown for additionalreturns. The ratoon crop matures earlier and requires less labor and water inputs.Water use efficiency is high.Rice ratoon cropping systems on a commercial scale have not been developedin tropical Asia chiefly because of a lack of cultivars specially suited to ratooncropping and with built-in resistance to insect pests and diseases, and because oflack of appropriate agronomic practices. Location-specific strains and suitableagronomic practices need to be developed to fit the tropical monsoon climate.This paper gives an overview of the status of rice ratooning and indicates thelines of research that need immediate attention to make rice ratooning a profitable