DIRECTIONS IN BREEDING FOR WINTER-WHEAT YIELD AND QUALITY IN SOUTH-AFRICA FROM 1930 TO 1990

Changes in the genetic yield and quality potential of South African wi nter wheat cultivars since 1930 were investigated by means of canonica l variate analysis. Yield potential improved by 87%, while test weight and protein percentage changed marginally. Flour colour improved most ly since 1965, but advancement of flour yield declined after 1984. Dou gh strength increased since 1930, yet current levels of dough strength should not be exceeded. When compared to farinograph assessment of do ugh strength, mixograph dough development time appears to be a less se nsitive indicator of variation in dough strength. Selection on the bas is of mixograph dough development time only, could influence a breeder 's perception of the dough quality profile of his breeding programme. Protein efficiency was maintained despite improvement in yield potenti al. Baking quality improved by 20%. The genetic winter wheat potential advanced significantly since 1930 in meeting the increased nutritiona l demands of the South African population.