Wheat, peanuts and rice under threat from climate change
Release Date 29 November 2006
Farmers across the world could see a dramatic drop in their harvest of wheat, peanuts and rice by the end of this century unless plant varieties are developed that are more suited to a warmer climate. Scientists from the University of Reading's Walker Institute for Climate System Research have found that peanut crops could drop by two thirds in India - the world's largest producer of peanuts - by the 2080s as a result of global warming. The scientists have been studying how a warmer world will affect future harvests. They focused on peanuts (or groundnuts) in India, which are used as food and to make oil. Dr Andy Challinor, lead author of the study, said: "Although the work so far has focused on groundnut in India, many annual crops – such as wheat, soybean and rice – have a threshold temperature above which seeds do not form properly leading to lower crop yields. This study of the peanut crop highlights a more general and important risk to food crop production world wide." Dr Tim Wheeler, from the Department of Agriculture at the University, added: "The crop model we have developed is now being used to study how high temperatures will impact other crops and in more regions, and to consider ways to cope with climate change – such as specifying new crop varieties for a changing climate." The study highlights the need to develop and test varieties of crops that will be able to cope better with extreme high temperatures. This kind of adaptation to climate change will be a particular challenge in developing countries that are likely to be hardest hit by climate change, but have less money to invest in ways to cope. As the world gets hotter, two things could happen to the grain crops that give us our staple foods like rice, flour and peanuts: - Very hot days will become more common. If they occur when a crop is flowering, seed may not form properly so there are less grains of rice or wheat to harvest. - A crop makes bigger grains if it grows slowly – as long as the crop has enough water and nutrients – because it has more time to develop large leaves and plump grains. Surprisingly, crops could actually grow too quickly in a warmer world and so they would make smaller grains. The Walker Institute scientists have for the first time modeled across the whole of India how different peanut varieties – some suited to warmer temperatures and some to cooler – will grow in a future climate. The biggest drop in yield – of 70% - happens with a variety of peanut that is sensitive to high temperatures, that does not get enough rain and which grows quickly. But a peanut variety able to cope better with extreme high temperatures and which grows slowly at warmer temperatures could actually produce more peanuts in the 2080s than now. ends A joint University of Reading Walker Institute and NCAS release Lucy Ferguson, senior press officer, University of Reading 0118 378 7388 L.Ferguson@reading.ac.uk Notes to editors: For more information and to arrange interviews please contact: Kathy Maskell or Maria Noguer on 0118 3787380. Alternative number: 0118 378 8316. The lead authors of the paper are: Dr Andy Challinor and Dr Tim Wheeler from the Crops and Climate Group, Walker Institute, University of Reading (www.walker-institute.ac.uk) The Crops and Climate Group is a multidisciplinary group of crop scientists, climate scientists, and physicists that study the impacts of climate variability and change on crops through research at the interface of agriculture and weather www.rdg.ac.uk/pel/cropsandclimate. The Walker Institute for Climate System Research at the University of Reading is concerned with understanding our climate, in order to deliver better knowledge of future climate and its impacts for the benefit of society. It is composed of groups from a number of departments across the University – including the Departments of Agriculture and Meteorology. See www.walker-institute.ac.uk. The work was carried out as part of the National Centre for Atmospheric Science – Climate Program www.ncas.nerc.ac.uk. Media contact: Dr Louisa Watts, Knowledge Transfer & Science Communications Manager Tel: 01793 411609 Email - NCAScomms@nerc.ac.uk The National Centre for Atmospheric Science - NCAS - carries out the UK's core academic atmospheric research program, including climate variability and climate change. NCAS is funded by the Natural Environment Research Council. The NCAS-Climate program addresses fundamental questions in understanding and forecasting climate variability and change and its impacts www.ncas.nerc.ac.uk. Funding also came from the EU FP6 Ensembles project Paper from which these results are drawn: A J Challinor, T R Wheeler, P Q Craufurd, C A T Ferro and D B Stephenson, 2006. Adaptation of crops to climate change through genotypic responses to mean and extreme temperatures. Agriculture, Ecosystems and Environment (in press), doi:1016/j.agee.2006.07.009. The scenario of future climate used in the study was derived from the Met Office Hadley Centre regional climate model - see the Met Office website - using the IPCC A2 scenario.