Crop and rain water management strategies for increasing productivity of rainfed lowland rice systems uri icon

abstract

  • The timing, frequency and amount of rainfall during the growing season determine the land productivity in a rainfed environment. For increasing productivity and stabilizing yield, technologies and strategies that minimize the effects of uncertainties in water availability are needed. This study, conducted in northern Luzon, Philippines, during 1991-1992, established the benefits of the dry seeding technique of rice crop establishment over the traditional transplanted method. During the study period, farmers with dry seeded rice (DSR) were able to establish the crop about 40 days earlier than transplanted rice (TPR) and utilized about 400 mm of the initial monsoon rains. The advantage of DSR is reflected in higher expected seasonal relative water supply (RWS) values of 1.08 at 50% and 1.04 at 75% probability, compared to 1.04 and 0.52, respectively, for TPR. Thus, crop water availability would not be a problem for either system of rice culture in an average year, but TPR would be severely affected by water shortage once every 4 years. DSR was harvested about 10 days earlier than TPR and provided a better soil-water regime for the following upland crop. In an average year, farmers growing mungbean after DSR can expect to meet 50% of the potential crop water requirement from rainfall compared to 37% for those who grow mungbean after TPR. The average yield of DSR was equal to that of TPR during the study period, but the significantly higher yields of mungbean grown after the DSR substantially increased the productivity of the rainfed lowland rice systems.

publication date

  • 1995
  • 1995
  • 1995