Mapping genes for flowering time and frost tolerance in cereals using precise genetic stocks

The development of comprehensive genetic maps based on molecular markers ha s increased the power of genetical analysis immensely in the last few years . Characters previously recalcitrant to analysis, such as abiotic stress re sponses, are now amenable, and individual major genes and QTL mediating the variation can be identified. This has allowed the development of strategie s for stress amelioration by adjusting the timing of the life cycle and int roducing genes which enable the plant to tolerate stress. These strategies are illustrated here by showing how genes for vernalization response and co ld tolerance on chromosomes 5A and 5D of wheat have been identified and loc ated. Additionally, their relationships to genes in other species, such as barley and rice can be characterised through comparative mapping approaches , leading to strategies for their isolation using rice genomic tools.