Sucrose, yield and disease resistance characteristics of sugarcane varieties under test in the SASEX selection programme

Varieties in test in the SASEX breeding programme during 1995 were compared, to illustrate trends in varietal development, and to assess the relative importance of diseases at different stages. It is apparent that there is a bias towards producing varieties with higher sucrose content and lower cane yield than control varieties. These varieties will contribute to achieving an 8:1 cane to sugar ratio, and also represent a gain in quality and profitability. Also obvious, is the large effect of disease on the selection programme, with 40% of the best varieties at each stage being rejected due to susceptibility to various diseases. This is a significant hidden cost to the industry, as many potentially high yielding varieties are not released because of disease problems. Possible solutions to this problem are discussed.