Cracking manuka's genetic code to mitigate myrtle rust

A nationwide science project that sequenced the mānuka genome and is now exploring its genetic diversity may be instrumental in protecting the indigenous plant from the fungal disease myrtle rust.

Using state-of-the-art genome sequencing technologies, scientists at Plant & Food Research, mapped mānuka’s genetic blueprint in 2015 and shared the information with tangata whenua and the New Zealand research community.

The research focus has since moved to using bioinformatic techniques to acquire a detailed understanding of the unique attributes of mānuka’s genetic stocks – the data have been gleaned from around 1000 samples of mānuka leaf collected nationwide in a collaboration with Landcare Research, the University of Waikato and key Māori partners.

The information generated is providing important scientific insights concerning the distribution and genetic diversity within and between mānuka populations in New Zealand.

“A key objective of the project has always been to understand how genetic material is exchanged between mānuka populations by pollen and seed dispersal to help whānau and hapū, and the honey industry, to develop unique stories around provenance, and help ensure genetic variation for conservation purposes,” says Plant & Food Research Science Group Leader Dr David Chagné.

“With the arrival of myrtle rust on the New Zealand mainland, we soon realised the need for an additional and more specific conservation application for the project.

“While it’s not clear just what effect myrtle rust will have on mānuka under New Zealand conditions, we should expect differences in susceptibility and resistance across the mānuka populations.

“By using the latest technologies for DNA sequencing and new methodologies for bioinformatic data analysis we can determine which parts of the genome are associated with tolerance.

“This will help us to better predict the potential damage from myrtle rust and determine how fast the various mānuka populations will respond to the disease.

“The data will assist with guiding research priorities for maintaining and protecting diversity in mānuka,” says Dr Chagné.

Research outcomes from the project are expected to be released between June and August this year.

“The project is a great example of collaboration between Māori landowners, two Crown Research Institutes and a university to provide real benefit to both the industry and the environment,” says the project lead Dr Gary Houliston of Landcare Research.

The Māori organisations assisting with stakeholder engagement and commercial support in the project are Ngati Porou Miere, Tuhoe Tuawhenua Trust, Atihau-Whanganui, Taitokerau Miere and Tai Tokerau Honey. The project is funded by the Ministry of Business, Innovation and Employment (MBIE).

Source: Plant & Food Research

Publication date: Thu 15 Jun 2017