Exploitation of interspecific biodiversity for wheat improvement

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The world's population is set to increase from 6-9 billion by 2050 and thus food production needs to increase by 70% over its present levels. In addition, climate change and the need to develop lower-input farming practises will significantly reduce the production of crops such as wheat. Unfortunately, due to modern breeding practises relatively little genetic variation is available in modern wheat varieties for breeders to develop superior adapted genotypes. The wild relatives (alien species) of wheat provide a vast and largely untapped reservoir of genetic variation (for traits such as tolerance to abiotic and biotic stress, biomass, yield and photosynthetic potential). This variation can be exploited for the development of new high yielding varieties adapted to climate change and environmentally friendly agricultural practises. Examples of previously successful introgressions from alien species into wheat include leaf rust resistance from Aegilops umbellulata (which saved US wheat production from catastrophic failure in 1960); resistance to a range of diseases, tolerance to acid soils and increased yield advantage from rye (in the late 1990s a 1B/1R translocation was present in the majority of the world's wheat varieties and is still present in leading varieties such as "Rialto"); a gene from Ae. ventricosa conferring resistance to eyespot is present in many wheat varieties; many of the top wheat varieties in Europe, e.g. "Robigus", carry genes derived from introgressions from Triticum dicoccoides. The BBSRC have recently funded a research programme aimed at transferring genetic variation to wheat from its wild relatives. These lines will ultimately be exploited to develop new superior high yielding wheat varieties which are adapted to climate change and environmentally friendly farming practises. This funded research programme is in the process of developing 1) large numbers of wheat/alien hybrids, produced by crossing wheat with its distant relatives, and 2) a series of lines of wheat carrying single chromosome segments derived from a range of alien species. For the full potential of this programme to be realised it is essential that the wheat/alien germplasm being generated is screened for a diverse range of traits in multiple environments. In order to do this the present application will assemble an international crop physiology cluster involving groups in the UK, Australia and India. While the research will have global application the emphasis of this programme will focus on developing superior Indian wheat varieties. Over recent years wheat production has stagnated in India with new varieties failing to provide significant improvements in yield potential primarily because of the adverse affects of biotic and abiotic stresses. The introduction of alien germplasm which combats these stresses is thus of critical importance for future wheat production in India.This group will undertake research and screen the wheat/alien germplasm being developed for a range of traits including tolerance to heat, drought (including water use efficiency), acid and alkaline soils and salt; resistance to disease; increased photosynthetic capacity/biomass production and nitrogen use efficiency.As a result of this research the crop physiology cluster will enable the identification of specific alien chromosome segments that carry genes that e.g. confer resistance/tolerance to biotic/abiotic stresses, etc. These alien chromosome segments will be directly incorporated into wheat breeding programmes in India at DWR and at the ARI. Furthermore, the data obtained from this programme will be channelled back into the BBSRC funded germplasm programme and in particular to the breeders associated with it in the UK for commercial exploitation. The material will also be exploited by Australian breeders thus providing a further link between the BBSRC and the Grain Research and Development Corporation (GRDC).