Crop and water productivity as influenced by rice cultivation methods under organic and inorganic sources of nutrient supply

A field experiment was conducted during the wet seasons of 2010 and 2011 at New Delhi, India to study the influence of organic, inorganic, and integrated sources of nutrient supply under three methods of rice cultivation on rice yield and water productivity. The experiments were laid out in FRBD with nine treatment combinations. Treatment combinations included three sources of nutrient supply viz., organic, integrated nutrient management, and inorganic nutrition and three rice production systems viz., conventional transplanting, system of rice intensification (SRI) and aerobic rice system. Results indicated that the conventional and SRI showed at par grain and straw yields but their yields were significantly higher than aerobic rice. Grain yield under organic, inorganic and integrated sources of nutrient supply was at par since the base nutrient dose was same. Plant growth parameters like plant height, tillers, and dry matter accumulation at harvest stage were almost same under conventional and SRI but superior than aerobic rice system. Root knot nematode infestation was significantly higher in aerobic rice as compared to SRI and conventional rice. However, organic, inorganic and integrated sources of nutrient supply did not affect nematode infestation. There was significant advantage in term of water productivity under SRI over conventional transplanted (CT) rice and less quantity of water was utilized in SRI for production of each unit of grain. A water saving of 34.5-36.0 % in SRI and 28.9-32.1 % in aerobic rice was recorded as compared to CT rice.