Polyphagous Shot Hole Borer on macadamias in South Africa

2019-08-05 12:33:00

Following the recent report of the polyphagous shot hole borer (PSHB) from a macadamia tree on the KZN North Coast, additional information and resources are shared with growers in this update.

The Department of Agriculture, Land Reform and Rural Development was informed of the most recent incursion of the PSHB onto macadamias on the KZN North Coast. The Department is also in the process of drafting phytosanitary guidelines which provide practical guidance on removing and disposing of infected trees and the movement of firewood, especially of confirmed reproductive hosts such as the black wattle etc. The Department is also finalizing control and quarantine measures according to the Agricultural Pests Act of 1983.

Please keep an eye out for an article outlining the PSHB disease complex, host range and control in the SAMAC Journal which will be available soon. More information on identification of the beetle and fungus, lists of reproductive and non-reproductive hosts and fact sheets are available on the Forestry and Agricultural Biotechnology Institute web page (https://fabinet.up.ac.za/index.php/research/7) and the new PSHB website (https://polyphagous-shot-hole-borer.co.za).

Dr Gerda Fourie, who heads the Macadamia Protection Programme at FABI also initiated a research project evaluating the susceptibility of different macadamia cultivars to the symbiotic fungus (Fusarium euwallaceae) of the PSHB. Through her association with the PSHB Research Network she is also involved in studying the biology and life cycle of the PSHB in different enviroments, documenting reproductive and non-reproductive hosts and evaluating control options.

Students inoculating macadamia trees and twigs with the PSHB symbiont, F. euwallaceae.

Courtesy of the Macadamia Protection Programme

Courtesy of the Macadamia Protection Programme

Growers are encouraged to remain vigilant, and to report any suspicious symptoms to SAMAC and FABI. Please also remeber that SAMAC members can make use of the Disease Clinic at FABI free of charge.