Scholarship helps with genotyping heritage apple cultivars research

Aaron Hewson is passionate about pushing the boundaries for horticulture and agriculture to future-proof growing food for communities, and his master’s research holds exciting potential for commercial orchards. 

Aaron, 22, the 2025 Horticulture New Zealand Postgraduate Scholarship recipient, has just completed the first year of his Master of Science in Plant Biotechnology at the University of Otago.

This scholarship is awarded to a student undertaking postgraduate study in horticulture or a related field and provides $10,000 cash.

Aaron’s research is focused on genotyping heritage apple cultivars at the Jim Dunckley Heritage Orchard in Mt Cargill, near Dunedin. The orchard is maintained by the Coastal Otago Branch of the Tree Crops Association.

The cultivars in the orchard were collected in the 1990s from locations across Otago and Southland, including from a former Plant & Food Research orchard.

However, over generations, the original identity of many of the heritage varieties had been lost, with some then given different names by local farmers.

The major focus of Aaron’s Masters studies, co-supervised by the Bioeconomy Science Institute (Plant & Food Research) and working alongside their expertise in apple breeding, is to use DNA from each different cultivar to identify which variety of heritage apple they are.

“There is a very good reason, apart from the historical side,” he says. “Heritage apples have an importance to the wider apple sector.

“Most of the modern commercial apples in supermarkets have been bred from a very narrow genetic base of only six apples.

“Yet there are around 10,000 heritage apple varieties worldwide. With climate change bringing increased temperatures and more disease and pests, we have to have genetic diversity to breed apple cultivars that can deal with those new challenges. So, we need to know what heritage apples we have in New Zealand, and how they relate to today’s apples.”

Ultimately, with trees in the collection fully identified, there is potential to provide germplasm to research bodies and apple breeders.

In his first year of research, Aaron has already successfully identified 80 per cent of the orchard’s heritage apples, matching them to known heritage varieties on an international database.

“The 20 per cent which have not been identified yet are also very interesting. It could be because those varieties are not yet on the database, or it could be that they are unique local New Zealand cultivars.”

Aaron’s passion for wanting to make a difference for people and places was forged growing up in urban Dunedin but with grandparents who are passionate about conservation.

“My father is from a rural town which connected me to farming and my maternal grandparents are focused on conservation and the outdoors and that was very formative for me.

“They have a property at Mt Cargill covered with native bush, which is mostly native bush and spending time there helped me to fall in love with plants and nature.”

He was awarded a HortNZ undergraduate scholarship for his initial studies at Otago where he gained a double major of Bachelor of Science in Agricultural Innovation and Plant Biotechnology and a Bachelor of Arts majoring in Religious Studies and a minor in Asian Studies.

“The scholarships have been a big help financially but what I have also really appreciated is being able to attend the Horticulture Conferences and learn so much more about the industry,” he says.

“Towards the end of my undergraduate studies, I was offered this research programme. Being awarded the postgraduate scholarship has given me the ability to really focus on my academic research.”

Alongside his studies, Aaron is also involved with organisations including Future Farmers.

“We want to be pushing boundaries for the future of agriculture and horticulture and that is relevant to what I am doing, helping to support the future of apples,” he says.

“I chose my university subjects because I want to be part of making a difference, help to improve the natural world and look after people and places. Agriculture and horticulture is where we can do a lot to support communities and conservation.”

As well as being awarded the Horticulture New Zealand postgraduate scholarship, Aaron was a 2025 joint recipient of his university’s 2025 Joan Mary Anderson prize for exceptional students who show the greatest promise for contributing to plant science.

While he says his future plans are still “a million dollar question” his goal is to “have a foot in both research and commercialisation”.

“My interest is in underutilised plants, like heritage apples and other food crops that are underrepresented in modern food using genetics to raise the status of these underutilised plants.

“Scientists are good at getting results but not always as good at getting them to the end user, so I would really like to be able to sit across both spectrums.”