Using wild ancestor plants to make rice more resilient to increasingly unpredictable water availability

Enabling food production to keep pace with population growth in the face of global climate change is a significant challenge. Both high and low extremes in rainfall increasingly limit food production, particularly for the poorest farmers. Furthermore, droughts and floods are predicted to occur more frequently under climate change, whilst the availability of water for agriculture will decline. The "green revolution" resulted in a doubling of rice yields across much of Asia, but demand for rice now exceeds production and UN FAO predictions suggest rice yields will need to increase by 50% by 2050 to meet population growth. A quarter of global rice production, rising to 45% in India, is in rain-fed environments thus at serious risk from climate change. New developments in modern plant breeding are allowing scientists to address this problem. The use of DNA based molecular markers that predict how adult plants perform under challenging environments such as drought allow breeding to be speeded up and different phenotypes or traits to be combined and transferred from one variety to another. These molecular tools make the selection process much more efficient so that what previously would have taken six generations can now be done in two. However, the loss of genetic diversity during the hundreds of years of domestication of crops such as rice means that the germplasm associated with modern cultivars offers limited scope for the improvements that are needed to meet the challenges of the 21st Century. The exciting thing about this project is that we will use new technology platforms developed in one of our laboratories at Cornell University, USA, to access valuable genetic variation from ancestral wild species of rice, introduce this to modern day elite cultivars that are widely grown in India and identify new varieties that have increased yields under drought conditions due to the presence of small segments of DNA from the wild species. Field trialling of hundreds of different lines carrying different segments of DNA from the wild species will be conducted by the Central Rice Research Institute in India and in parallel researchers at the Universities of York and Cornell will carry out a range of different experiments to understand what causes increased drought resistance in specific lines. With this new understanding it will be possible to develop new DNA based molecular markers that allow the genetic variation from the wild species to be efficiently transferred to a wide range of commercial rice cultivars. So the outputs during the four year project will not only be improved rice varieties but also new breeding tools for rapid deployment of drought conferring genetic variation to multiple rice cultivars. However, the adoption of new rice varieties by local communities is dependent on multiple factors in addition to yield performance with grain quality being one of the most important. Cultural and sociological issues such as the role of gender also play a significant part in determining the success of a new cultivar and in order to address this we will perform a socioeconomic study to assess the likely uptake patterns of any new varieties and their impact on farmers' incomes. The impact of new rice cultivars on yield, per unit cost of production, and total production per specific input (land, labour, fertilizers, seeds) will be evaluated and on-farm testing and participatory evaluation will be an integral component of cultivar field trials. This project will also model the impact of new varieties to quantify how yields are enhanced in drought-prone landscapes currently and in the future as climate changes. This information along with the outputs from our socio-economic studies will inform policy makers in developing countries about the socio-economic benefits of new varieties and thus improve adoption of the most effective strategies to address food insecurity and poverty.