Management interventions to enhance water productivity in dry-seeded rice (Oryza Sativa L.)

Rice (Oryza sativa L.) is grown in alluvial irrigated tract of north-west India due to high productivity and profitability. Rice is the major source of calories for half the world'spopulation as well as in our country (Roy and Bisht, 2012). However, large amount of water input in rice culture has led to over-exploitation of groundwater as indicated by alarming fall in water table. Average fall in water table in Punjab and Haryana state has been more than 0.75 m year-1 in the last decade (Minhas et al. and Humphreys et al. 2010). Thus, there is a need to explore alternate techniques that can sustain rice production and are resource conservative. On the face of global water scarcity and escalating labour rates, when the future of rice production is under threat, direct seeded rice offers an attractive alternative. In this regard, dry-seeded rice (DSR) is one option that can help in saving water, energy, labor and time. Management interventions that reduce irrigation water and increase water productivity (WP) are required in dry-seeded rice. Irrigation scheduling, tillage and short duration cultivars are some of the interventions in this regard. Irrigation scheduling aimed at eliminating over or under irrigation and ensures optimum yields with high water productivity. Tillage affects crop growth by altering soil edaphic environment. Rice plants are unable to utilize soil water in the deeper layers because of shallow root system. Deep tillage has emerged as a better option to improve deep root growth (advantageous for water extraction during drought in upland rice) of rice cultivars. Based on the existing evidence, present paper reviews the management interventions to enhance water productivity in dry-seeded rice.

Deep tillage enhanced productivity of dry seeded rice in irrigated subtropical environments.

Tillage gains on productivity is greater in in-frequent irrigation regimes than frequent irrigation regimes.

Short duration cultivars in rice saves more water than medium or long duration cutivars.