The aim of the project was to work with regional Tangata (champions) upskilling mana whenua to be able to contribute meaningful knowledge to this biosecurity threat. Capability building in host and pathogen indentation, surveillance and reporting is important empowering mana whenua to continue to be kiatiaki (guardians) when new diseases arrive. Training was carried out across the motu (country) in areas where myrtle rust had been identified. Place-based learning is important to Māori as it considers is inclusive of tikanga (customs) of the area and creates a greater connection with place. Traditionally Mmāori passed down information verbally through stories, waiata (songs) and symbolism through weaving. 

The main priorities and knowledge needed for Māori and communities to tackle the spread of myrtle rust, was:

• UTo understand the pathogen and, it’s lifecycle 

• Know native Myrtaceae and identify key susceptible and hosts.

• CTo be able to confidently identify the pathogen.

• Know how to report positive finds.

• Have the knowledge to undertake control measures to reduce the risk of spread. 

Understanding the pathogen. Wwhakapapa: m, Myrtle rust is native to South America where it causes little concern and has become a global invader establishing in North America, Hawaii, Australia, New Caledonia, and Aotearoa (ref). Myrtle rust was first detected on Metrosideros kermadecensis, kahikā rangitāhua in Aotearoa on Raoul Island of the Kermadec Islands, Rangitāhua in March 2017(ref). In May 2017 it was reported on the mainland in a Kerikeri nursery in the Bay of Islands and subsequently in Taranaki, Te Kuiti and Te Puke in Te Ika-a-Māui North Island. The locations of the initial infection sites were consistent with known wind events from Eastern Australia that spread the airborne spores to Aotearoa. 

The disease triangle is a fundamental concept that is needed to understand myrtle rust, it   consists of three key factors and all factors must be present in order to cause disease. The pathogen, a susceptible host (plant) and suitable environmental conditions. For myrtle rust to infect a plant it first needs to find a susceptible Myrtaceae spp. host and needs moist, warm temperatures (bBetween 15°C and 25°C are optimal for germination). The infection process starts with the spore landing on susceptible plant tissue, specifically the new actively growing plant parts, leaves, stem, flowers, and fruit. The spore then sends a tiny tube-like structure called a germ tube that seeks out the plant surface that develops an appressorium that attaches to the plant surface. This structure then sends out a penetration peg that pushes though the surface and into the plant cells. The fungus then feeds on the nutrient rich cells and produces more spores in pustules that burst through the leaf surface (Figure 1). A single pustule can contain thousands of spores, it only takes one spore to start the infection process. These spores then become airborne or can be transported by, birds, insects, humans and equipment.