Soil Science Division - Improved Alternate Wetting and Drying Technique (Improved-AWD) in Rice Cultivation

Technology

2 – 3 weeks after the crop establishment, irrigate the field up to 5 cm and allow to drain until water level goes down to 15 cm below soil surface
Irrigate again up to 5 cm and allow draining as above
Continue the procedure until first flower appearance
- Maintain 0 – 5 cm water level for two weeks from first flower appearance
Stop irrigation and allow draining out water level goes down to 15 cm below the soil surface
- Practice again AWD until 2 weeks before expected date of harvesting and then stop irrigation

Important

To measure water level in the soil, use a PVC pipe/tube (diameter – 4”, length – 20 cm) making several cuts along the wall (Figure 1)
Insert the PVC tube to the soil 15 cm below soil surface by removing mud inside (Figure 2)
Number of tubes per area depend on landscape of the paddy tract (e.g. 3 tubes/Ac if land is flat)
Mark where PVC tube is installed (Figure 3)
Measure the water level inside the tube using a ruler (Figure 4)
Apply fertilizer when the soil is moist and pay attention to control weeds at land preparation and before starting AWD
Improved-AWD is not suitable for saline paddy fields

This technology should be practiced in entire Yaya or water distribution channel with the collaboration of famers, agriculture officers and irrigation officers to get better results
Improved AWD is highly suitable for major and minor irrigated areas of the Dry and Intermediate Zones

Benifits

Reduced 2 – 3 irrigations practices per season and 10 – 20% of total water can be saved
Saved water can be utilized to expand the cultivated extent, to cultivate long age varieties, to implement mid season cultivation and to start the next season in time.

Principal inventor

M.U.K. Rathnayaka, Assistant Director of Agriculture (Research), Rice Research and Development Institute, Bathalagoda

Collaborators

rrdi_technology_soilscience_IAWD