Direct-Drill Seeded Rice: A Need of the Day.

Rice-wheat system of the Indo-Gangetic Plains (IGP) in South Asia is vital for food security in the region. Conventional rice production method [puddled transplanting (CT-TPR) is labor, water and energy intensive. Due to labor shortages, transplanting cost has gone up from US$ 30 ha^-1 in 2007 to US$ 50 to 70 ha^-1 in 2008. In many parts in the region, water is becoming increasingly scarce. Groundwater tables have fallen at a rate of 0.5-0.7 m yr^-1 in Indian Punjab and Haryana due to pumping of groundwater for rice. All these factors are making conventional system less profitable. Direct-drill seeded rice (DSR) as alternative to CT-TPR has potential to overcome these emerging constraints. The benefits of DSR include savings in (1) water (12-60%); (2) labor (20-30%); and (3) cost of production. Performance of DSR in on-station and on-farm trials across the IGP has been variable ranging from lower, equivalent or slightly higher yield than CT-TPR. However, DSR relative to CT-TPR performed better in the eastern IGP than in the northwestern IGP. Results suggest that optimal land leveling and weed management are crucial for the success of DSR. Technologies for land leveling and crop establishment are available in the region. However, variability in rainfall pattern and unavailability of timely water supply can adversely affect crop establishment. Weed control remains the major constraint. A multilocation study initiated in 2008 revealed that pre-emergence (pendimethalin) followed by bispyribac 20 DAS or cover crop (sesbania and cowpea) before rice and bispyribac 20-25 DAS or bispyribac+azimsulfuron 15-20 DAS or bispyribac/penoxsulam/fenoxaprop+ethoxusulfuron 20 DAS were effective in controlling weeds depending on weed flora. In conclusion, DSR is need of the day and has potential to substitute CT-TPR but challenges remain to develop effective integrated weed management program, precise water management and development of new plant types suited for DSR.