Several diseases occur on sunflowers in South Africa. All diseases are influenced by the disease triangle, which includes environmental factors, host characteristics and the pathogen itself (namely, pathogenicity and inoculum). All diseases occur sporadically. However, certain diseases occur more regularly than others.
Nematodes are wormlike organisms, only visible with a microscope, and are an important sunflower pest that can cause serious damage. They live in plant roots and the root zone. In contrast with the temperate climate zones of the world where sunflowers are extensively produced, the predominantly sandy soil and semi-arid climate of South Africa is a favorable habitat for nematodes.
The ARC – Agricultural Research Council released the SDIC - Sunflower Disease Identification & Control Application. The application aims to assist farmers with the identification of a native population of disease organisms that can be a sunflower production challenge. Diseases are categorized as Fungal and Fungus-like diseases, Bacterial and Phytoplasma diseases, Viral diseases and Nematodes. Diseases are also identified via an interactive map according to the province and regions within the selected province.
In addition the SDIC Application supplies information on effective management and control, which include cultural practices, fungicides, as well as resistance. In addition, the application includes a library of sunflower disease information files, focusing on Geographic occurrence and impact, Symptoms/signs, and Biology and epidemiology.