Productivity trends in southern and central regions and the impact of new varieties

Productivity data were analysed for the period 1966 to 1994 for seven mills in the Bundaberg and Mackay regions. A five-year moving average method was used to minimise fluctuations caused by environmental variation. The reversal in declining ccs trends in both regions in recent years corresponded well with the increasing production from new varieties CP51-21, Q141 and Q146 in Bundaberg, and Q124 in Mackay. In Bundaberg, ccs levels are now the highest they have been for at least the past 30 years. Evidence is presented to show that about two-thirds of the increase in ccs in Bundaberg was due to these new varieties, while Q124 was responsible for 40%-50% of the increase in Mackay. Sugar yields and, in most cases, cane yields are beginning to show upward trends, although only at Bingera was this short-tenn trend significant. This again corresponded well with the increased production from new varieties, although residual environmental effects in Mackay mills made interpretation difficult.