Simulation of impact of projected climate change on wheat in India

The problem of global climate change due to natural processes and anthropogenic sources and its impacts on world food security in general and its regional impacts in particular have come to forefront of the scientific community in recent years. Though the uncertainty of projected climate change at the regional level is higher, it is still necessary to assess its impacts on crop productivity for formulating response strategies. Climate change scenarios projected by the middle of the current century, based on the latest studies, were created and the impacts of concurrent changes of temperature and CO2 on the growth, development and yields of wheat in northwest India were quantified using a state-of-the-art dynamic simulation model. Yield enhancements of the order of 29-37% and 16-28% under tainted and irrigated conditions respectively in different genotypes were observed under a modified climate (T-max + 1.0degreesC, T-min + 1.5degreesC, 2 x CO2). Any further increase beyond 3degreesC cancelled the beneficial impact of enhanced CO2. Adaptation measures to mitigate the potential impact of climate change included possible changes in sowing dates and genotype selection. Enhancement of sowing by 10 days in late-sown cultivars and delaying of sowing by 10 days in normally sown cultivars resulted in higher yields under a modified climate, whereas a reduction in yield was observed in the reverse strategies. Copyright (C) 2003 Royal Meteorological Society.