Prediction of oil quality of sunflower from temperature probabilities in eastern Australia

Abstract

The probability of the occurrence of temperatures suited to the production of high quality sunflower oil has been examined for 37 locations in eastern Australia. The results indicate that temperatures suited to development of oil with =62% linoleic acid occur throughout the potential cropping season with a probability =0.6 in Tasmania, south-western Victoria, south-eastern South Australia and the highlands of New South Wales. In most established cropping regions probabilities of this level are reached only in the later third or half of the sunflower growing season. The probability of temperature suited to production of oil with = 72 % linoleic acid is less than 0.6 in all regions for much of the season, and in any environment only very late-sown crops can be expected to yield oil of this quality. The results are discussed in the light of factors controlling the distribution of sunflower production, and it is concluded that, with existing genotypes, adequate supplies of high quality oil to meet market requirements will not be reliably available from the Australian crop.