INTER-VARIETAL CHROMOSOME SUBSTITUTION LINES IN WHEAT - REVISITED

The difficulties in developing inter-varietal chromosome substitution lines in wheat are reviewed. The use of genetical, cytological and mol ecular markers is suggested as a way of overcoming them. These difficu lties and the use of markers, as well as the need to develop duplicate lines to detect background variation, are described using the develop ment and analysis of the Cappelle-Desprez (Bezostaya 1) chromosome sub stitution set as an example. The effects of substituting Bezostaya 1 c hromosomes on final plant height and adult-plant resistance to yellow rust are reported. The large number of aneuploids and substitution lin es available in wheat provides a tremendous, international resource, w hich should be exploited in the future.