The relative importance of cane yield and traits affecting CCS in sugarcane varieties

The traits 'cane yield' and 'CCS of sound stalks' currently receive most attention in most stages of selection in Australian sugarcane breeding programs. With adoption of green cane harvesting, other traits that may affect mill CCS have come under increased scrutiny. Lodging, suckering propensity, and degree of trashiness (amount of dead leaf at harvest and how tightly it is held to stalks) are three traits known to vary among varieties that may affect mill CCS and cane yield. As part of a wider study, the economic importance of genetic variation in these traits from a whole of industry perspective was estimated for different regions. The importance of this variation was compared with changes in cane yield and CCS per se. The results suggested that, if efficient methods of assessing lodging propensity, trashiness and suckering propensity could be developed, then it would be of value to incorporate these traits in a selection index from early stages in selection systems in breeding programs. Further research is needed to develop and assess selection indices incorporating these traits for different stages of selection, and assess the role of managed environments in selection associated with lodging and suckering. While highly speculative at this stage, a possible structure of a selection scheme incorporating selection for non-whole stalk traits affecting CCS is discussed.