Performance of rice (Oryza sativa) varieties at different spacing under system of rice intensification (SRI) in mid hill acid soils of Sikkim Himalayas Avasthe R.K.1, Head, Verma S., Senior Technical Officer, Kumar Ashok, Scientist (Senior Scale), Rahman H.2, Joint Director ICAR Research Complex for NEH Region, Sikkim Centre, Tadong, Gangtok, Sikkim 737 102 1Divsion of HRD, Central Soil and Water Conservation Research & Training Institute, Dehradun, Uttarakhand 248 195 2ICAR Sikkim Centre, Tadong *Corresponding author Email: ravisikkim@yahoo.co.in
Online published on 10 April, 2012. Abstract Field experiments were conducted at the ICAR Sikkim Research Farm, Tadong located at an altitude of 1450 m amsl in the per-humid mid hill acidic soils during kharif (rainy season) of 2008 and 2009 to evaluate the performance of four rice (Oryza sativa L.) varieties viz., ‘RCPL 1-87-8’ (medium-duration, 125 days), ‘Pusa Sugandh-2’ (medium-duration, 130 days), ‘RC Maniphou-7’ (long-duration, 150 days) and one local cultivar ‘Thulo Attey’ (longduration, 155 days) under different spacing in system of rice intensification (SRI) compared with conventional rice cultivation. ‘RC Maniphou-7’ recorded the highest grain yield (6.73 t/ha), N uptake (124.8 kg/ha), P uptake (40.5 kg/ha), K uptake (84.3 kg/ha), water use efficiency (2.879 kg/ha-mm), net return (Rs. 72,750) and benefit: cost (2.09) at 20 cm × 20 cm spacing under SRI. Total N, P and K uptake was the highest in SRI with a spacing of 20 cm × 20 cm in ‘RCLP 1-87-8’, ‘RC Maniphou-7’ and local cv ‘Thulo Attey’ over conventional rice cultivation. The optimum spacing under system of rice intensification for ‘RCPL 1-87-8’, ‘RC Maniphou-7’ and local cv ‘Thulo Attey’ was 20 cm × 20 cm. ‘Pusa Sugandh-2’ recorded a 2.0% yield decrease at 20 cm × 20 cm and 23.0% yield decrease at SRI 10 cm × 10 cm, as compared to conventional rice cultivation and did not respond to SRI. Top Keywords Acid soils, Long duration rice, Manure, Mid-hills, Mountain regions, Medium duration rice, Nutrient uptake, Water use efficiency. Top |