Myrtle Rust Pathogen now also in Limpopo 2014-07-31
In May 2013 the Myrtle rust pathogen, Puccinia psidii, was detected for the first time in South Africa (on a non-native, ornamental tree, Myrtus communis). This was on the KZN south Coast (see attached paper). Recently, the pathogen was detected at a second site in South Africa, this time on a native South African host in the genus Eugenia.
The second confirmed report of P. psidii, unexpectedly, comes from the Wolkberg Wilderness area near Haenertsburg and Tzaneen in the Limpopo Province. The fungus was found on two native Eugenia sp. trees in the native forest near Serala Peak. Finding it in a relatively remote area since as this means that it most likely also occurs in other areas in the region.
We encourage all foresters, conservation workers, farmers and any interested person, especially in the Wolkberg/Tzaneen areas, to keep their eyes open for the Myrtle rust pathogen. To date, it has only been found on plants in the Myrtaceae, including species of Eucalyptus, Eugenia, Psidium (guava) and Syzygium (waterberry/umdoni genus). The Myrtaceae includes a number of popular garden ornamentals and fruit trees (eg. guava, rose apple etc.). Myrtle rust may thus be found not only in Eucalypt plantations, but also in your garden and town. The pathogen mostly infects young, green tissue, and results in masses of yellow spores in single or multiple spots on young leaves, fruits and stems.
If you think that you have seen the disease, or need more information on it, please contact Prof Jolanda Roux at FABI immediately. Her email address (without the space) is jolanda.roux@ fabi.up.ac.za