Productivity and water use efficiency of aerobic rice under different moisture regimes in Eastern India

Abstract

A field experiment on aerobic rice culture was initiated at the Deras Farm,Mendhasal in Khurda district, Odisha during summer season (January to April) of 2007 and 2008 with the objective of identifying the suitable variety and irrigation regime for aerobic rice culture. Under aerobic condition, three rice varieities Lalat, Surendra and Kandagiri were directly sown in the main field without puddling. All the varieties were also sown on the same day in nursery and transplanted 25 days after sowing. Irrigation treatment consisted of I2 -keeping soilmoisture at 80-90% of available soil moisture (ASM) throughout the crop season, I3-keeping soil moisture at 60-70% of ASM during vegetative and thereafter 80-90% and I1 -keeping soil moisture at 60-70% of ASM throughout the crop season and I4-Conventional rice cultivation. Growth and yield characters were significantly influenced by establishment methods, irrigation regime andvarieties. Initial plant growth characters like plant height, tiller number were higher under aerobic rice. However, as the season advanced, values of growth characters were higher under transplanted rice. Yield attributes panicle numbers, grains per panicle were also higher under transplanted rice. Among irrigation regimes under aerobic culture, higher values of yield attributes were recorded in the treatment I1 . Under aerobic rice root mass density was maximumunder Kandagiri, which was followed by the variety Lalat. The highest yield (4.88 t ha-1 ) was recorded in the variety Surendra under transplanting method. In aerobic condition, the highest grain yield (3.98 t ha-1 ) and higher water use efficiency (46 kg ha-1 cm-1) wasrecorded in the variety Surendra, irrigated at 80-90% soilmoisture content (I1 ).