Agricultural biodiversity will be affected by the magnitude and rate of climate change, its geographical extent and seasonal patterns with some regions benefitting from chances while others suffer. Crop breeding, based on selection and cross-breeding or hybridization of genetically different strains are used to improve crop immunity or resistance to yield reducing diseases. Breeding can also enhance heat tolerance, and help plants adapt to higher levels of atmospheric carbon dioxide and altered frequencies and intensities of extreme precipitation events (Hillel and Rosenzweig, 2005).