Int.J.Curr.Microbiol.App.Sci (2019) 8(2): 554-565 554 Original Research Article https://doi.org/10.20546/ijcmas.2019.802.063 Water Management and Planting Methods Influence Growth, Spikelet Sterility and Nutrient Acquisition in Aerobic Rice Arjun Singh, Anchal Dass*, Shiva Dhar, C.V. Singh, S. Sudhishri, Teekam Singh, G.A. Rajanna and Pooja Pande ICAR-Central Rainfed Upland Rice Research Station (CRURRS), Hazaribagh, Jharkhand-825302, India *Corresponding author ABSTRACT Introduction Rice (Oryza sativa L.) constitutes staple food for more than half of the India’s population and plays an important role in country’s food security. India should produce additional 50 mt of rice at growth rate of 3 m t annually to feed 1523 million population by 2030 (CRRI International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 8 Number 02 (2019) Journal homepage: http://www.ijcmas.com Aerobic rice (Oryza sativa L.) is widely grown in eastern India. Soil moisture stress and unscientific ways of sowing, limit its yield and grain quality. Thus, a field experiment was conducted at Central Rainfed Upland Rice Research Station, Hazaribagh, Jharkhand, India during rainy season of 2016, to study the effects of irrigation regimes, soil adjuvants and planting methods on growth, and uptake and portioning of micro-nutrients in aerobic rice. The experiment was laid-out in a split-plot design replicated thrice. The treatments included 4-irrigation schedules, irrigation at 0.9, 1.2, 1.5 IW/CPE ratio and no-irrigation (rainfed), and 2-soil adjuvants (soil adjuvant applied and no-soil adjuvant) allotted to main-plots and 2-planting methods–conventional dry seeding at 20 cm row spacing and spot-sowing (dibbling of 4-seeds/hill at 20 × 15 cm interval) to the sub-plots. Irrigation at IW/CPE 1.5 exhibited the highest tiller count which was 4.2, 10.6 and 18.7% higher than IW/CPE, 1.2, IW/CPE 0.9 and rainfed treatment. The conversion of tillers to effective tillers was higher in IW/CPE 1.5 and 1.2 than water stressed crop (IW/CPE 0.9 and rainfed). Irrigation at IW/CPE ratio 0.9, 1.2 and 1.5 caused 16, 25 and 40% enhancement in filled-grain weight panicle -1 , respectively, over rainfed crop; the corresponding reduction in grain sterility was 21, 33 and 47%. Total uptake of Fe, Zn, Cu and Mn went up by 23.3, 24.6, 24.4 and 24.4%, respectively, in IW/CPE 1.5 over rainfed condition. Micro-nutrient harvest index and partial factor productivity of applied N, P and K also stood highest in IW/CPE 1.5. Spot-planting resulted in significantly larger tiller-count, higher number of panicles m -2 with larger and heavier panicles compared to conventional planting. Micro-nutrient accumulation and harvest index were also higher with spot- planting. Soil adjuvant application did not express significant effect on any of the studied parameters. Hence for better crop growth and accumulation of micro-nutrients and their larger portioning towards grains, aerobic rice should be spot-planted and irrigated at IW/CPE 1.5 under adequate water supply and at IW/CPE 1.2 when water is limited. Keywords Adjuvant, Aerobic rice, Irrigation, Nutrient harvest index, Partial factor productivity, Spot- planting, Sterility Accepted: 07 January 2019 Available Online: 10 February 2019 Article Info