Topic: Fungicides provide a pathway for finding myrtle rust resistance in Syzygium maire

Presenter: Robert Beresford, Honorary Fellow, Bioeconomy Science Institute, Auckland 

Five urban community groups across Auckland are focused on protecting nationally threatened Syzygium maire (maire tawake; swamp maire) from the devastating impact of myrtle rust by making judicious use of fungicides to protect remnant forest stands. Without protection, myrtle rust destroys flower buds in spring and all new shoot growth during summer. The flowers and fruit on the lower branches of 5-6 m tall trees can be protected by ground spraying to allow flowering, fruiting and seed collection. The seedlings raised go into a resistance screening trial, relying on natural infection, to see if more resistant individuals can be identified for replanting in the wild – a kind-of ‘enhanced natural selection’. S. maire is an interesting host, being a hydrophyte that lives in swampy ground close to watercourses. This limits where fungicide spraying can occur and research is needed to see whether the fungicide use could be altering the aquatic ecology in sprayed areas. Extensive field trials to see if more environmentally safe alternatives to agricultural synthetic fungicides could be used, however, none of the alternatives have performed well enough to be practically useful.

Stay tuned for registration details!

For more information on this series, please email PCA’s Myrtle Rust Recovery Project Manager Jules Freeman.

https://www.anpc.asn.au/myrtle-rust-management-for-practitioners-open-series/