Impact of elevated carbon dioxide and temperature on wheat production under sub temperate climate in north western Himalayas, India

Wheat is the second most important cereal crop and plays a key role in food and nutritional security. The study examines the impact of elevated carbon dioxide and temperature under limited irrigations on wheat crop using crop growth simulation models under sub temperate climate. The Info Crop model was validated using the historical data generated by the research trials of All India Coordinated Research Improvement Project at Palampur, Himachal Pradesh. The model was run for 20 years from 1991 to 2010 for Palampur weather station. The results revealed 3.6 to 4.0 percent and 1.7 to 7.5 percent increase in simulated crop yield with 420 and 470 ppm CO2 respectively. The elevated maximum and minimum temperature by 1 and 20C with 370 ppm carbon dioxide reduced the anthesis period by 5-7 and 9-11 days respectively over the sowing window of November 15th to December 30th. Similarly, days to maturity also reduced by 4-5 and 7-8 days with 1 and 20C rise in temperature respectively. The simulated crop yield showed increase by 17.9 to 63.0 and 33.2 to 133.4 percent with 1 and 20C rise in temperature at 370 ppm CO2 under limited irrigations. The simulated grain yield at 420 ppm CO2 showed an increase of 23 to 69.7 percent with 10C and 39.5 to 123.5 percent with 20C whereas at 470 ppm CO2 level the increase was 27.9 to 76.1 at 10C and 46.4 to 133.0 percent with 20C rise in maximum and minimum temperatures respectively. Hence, simulated results of elevated temperature and CO2 levels proved to be beneficial in rabi wheat with adaptations strategy of limited irrigations under sub temperate climate of North Western Himalaya