Etiology of rachis tip dieback of macadamia flowers in Australia

are reported here as novel pathogens of macadamia racemes. The high diversity of fungal species obtained revealed that multiple species can infect the same racemes and co-occur in the same tree expressing RTD symptoms. This study revealed that RTD has a biotic cause and is part of the flower blight disease complex in macadamia. The contributions of RTD to yield losses and a potential tool for predicting flower blight severity to support management decisions are discussed.