​Macadamia post-harvest physiology

The South African macadamia industry currently loses considerable revenue due to physiological problems associated with the crop. Kernel dis-colouration is a physiological disorder which reduces the quality of kernel, currently affecting more than R10 million worth of product each year. Since the disorder varies considerably between regions, a survey is currently under way to determine the factors which determine these regional differences. This should lead to an intervention strategy which allows the disorder to be minimized in the worst affected areas.

Another project under investigation at ARC- ITSC is the use of ethephon to cause nut abscission. The South African industry currently relies heavily on the ‘Beaumont’ cultivar since it yields very good crops. However, this cultivar does not drop mature nuts which then have to be harvested by hand from the tree. This leads to quality problems, as the nuts spend too long a period on the tree. It also results in high labour costs due to the number of man-hours needed to strip the trees. The project has shown considerable success and a product to deal with nut abscission should be registered in the next two seasons.



Contact Email: infoitsc@arc.agric.za