30 Apr 2025

NZ scientists share passion for high-value fruit with Vietnamese farmers

7:42 am on 30 April 2025
Passionfruit on the vine in Vietnam.

Passionfruit on the vine in Vietnam. Photo: SUPPLIED/P&FR

New Zealand scientists are teaming up with more than 70 farmers across rural Vietnam to enhance and future-proof the production of passionfruit in the Southeast Asian republic.

A team from Plant and Food Research had worked with the Socialist Republic of Vietnam on the Viet Nam Climate-Smart Fruit Value Chain project, known as VietFruit, for more than two years.

In that time, the plant science team carried out field trials and surveys to understand and improve production and post-harvest practices of passionfruit in key growing regions, the Sơn La province in the republic's northwest and Gia Lai in the Central Highlands.

Next, the New Zealand scientists will go to farms scattered across the two provinces to learn first-hand from local farmers the challenges and opportunities in harnessing passionfruit as a high-value, climate-resilient crop.

Plant and Food Research senior scientists and plant virologist Karmun Chooi in Vietnam.

Plant and Food Research senior scientists and plant virologist Karmun Chooi in Vietnam. Photo: SUPPLIED/P&FR

Empowering Vietnam's farmers to harness passionfruit's high-value opportunities

Agriculture made up about 11 percent of Vietnam's GDP and employed millions of farmers, growers and fishers throughout the S-shaped country of 100 million people with a coastline along the South China Sea.

Aotearoa contributed to various international development programmes in the Vietnam in recent years, including scientific projects in agriculture, which played a vital role in the Vietnamese economy following manufacturing.

Passionfruit, known locally as chanh dây, was already a significant horticultural crop for Vietnam, with around 12,000 hectares cultivated last year - most of which was exported, earning around $371 million.

The volume of these exports was expected to soar in the coming years, as Vietnam secured market access for passionfruit into Australia last year, was in negotiations for entry into the United States, and it gained access most recently to China, known for its strict biosecurity and pest control protocols.

The Ministry of Foreign Affairs and Trade allocated $6.2m to the VietFruit project in March last year, aiming to increase Vietnam's exports of passionfruit - and in turn, support its agriculture sector to build climate and disaster resilience and develop a more skilled workforce.

Taking VietFruit to the republic's female, ethnic minority farmers

The VietFruit project was a partnership between Plant and Food Research and Vietnam's Ministry of Agriculture and Rural Development, plant nurseries and research institutions, the Southern Horticultural Research Institute of Vietnam (SOFRI) and the Northern Mountainous Agriculture and Forestry Science Institute (NOMAFSI).

Senior scientist and project co-lead Dr Karmun Chooi said the team had spent more than two years working to understand cultivation and production of passionfruit, its threats, and the value chain.

"We're looking at how once we've harvested the fruit, how to transport that fruit and store that fruit so it's the best quality fruit for consumption in-country, but also exported," Chooi said.

"We're just about to start the extension part of the project, so the biggest opportunity now is really delivering our best insights so far in the project to the industry."

Plant and Food Research senior scientist Karmun Chooi studying passionfruit in Vietnam.

Plant and Food Research senior scientist Karmun Chooi studying passionfruit in Vietnam. Photo: SUPPLIED/P&FR

She said they will work with seven groups of 10 Vietnamese farmers across the two provinces, with a focus on ethnic minority farmers and female-led farmer collectives, to carry out farm trials of various management techniques.

Some trials will include ensuring high hygiene standards along the supply chain, enforcing strategic pruning similar to kiwifruit in New Zealand, appropriate agrichemical application and honing timing for planting and harvesting.

"We're able to provide them hopefully practical solutions that they can slightly change maybe the way they cultivate, just to improve - particularly for the ethnic minority - simple ways where they can improve the production to get higher yields and better quality fruit, so they're able to sell that or continue that on into the value chain, while increasing incomes back to their families and to the village," Chooi said.

"We're also working with nurseries that supply the plant material to ensure that the highest health plants are actually provided to farmers, so they produce the the best crops."

VietFruit objectives for passionfruit:

  • Control, detect and manage plant diseases
  • Strategic pruning for greater yields
  • Perfecting agri-chemical application spray programmes
  • Improve hygiene practices
  • Advance post-harvest protocols towards a high-value supply chain

Next was the development of a low-cost plant disease diagnostic tool to detect viral plant diseases, she said.

"So this is where we are hoping to be able to provide the nurseries but also other laboratories the ability to do these diagnostics."

Passionfruit struck by disease during farmer discussion groups in Vietnam.

Passionfruit struck by disease during farmer discussion groups in Vietnam. Photo: SUPPLIED/P&FR

Chooi said the goal was not to just give farmers protocols, but to improve their own knowledge bases so they could become "their own scientists" and improve growing passionfruit and other crops.

She hoped the insights would be useful to the wider horticultural industry.

"First, we'll work with innovation groups, then we'll also invite the wider extension, so some of the commercial companies, and nurseries that sell seedlings," she said.

"The best way for people to learn is through talking to farmer to farmer, so we'll invite everyone and we'll have a big, open discussion and forum hopefully within the next year."

Enabling climate-smart, resilient farming systems

Climate change adaptation was a new pillar in the new comprehensive strategic partnership signed between New Zealand and Vietnam in February, in celebration of 50 years of diplomatic ties.

Project co-lead and Plant and Food Research's international development programme manager Stephanie Montgomery, based in Cambodia, said farmers in Southeast Asia were dealing with more unpredictable weather patterns due to climate change.

She said the team explored ways to help "buffer" farmers against changes to the typical wet and dry periods to ensure they maintained good volume and quality yields - like increasing cover cropping to protect against erosion or increasing water storage options.

"There are a lot of climate impacts and generally we're seeing extended periods of either drought or flooding," Montgomery said.

"We really look at the problem and see how pragmatically we could implement something that will benefit the farmers that they are able to adopt themselves."

Montgomery said they were trying to address climate impacts on passionfruit production in Vietnam's Sơn La and Gia Lai provinces, and seeking to improve climate resilience.

"In Sơn La, it's a very steep terrain and the passionfruit is grown on the side of these very steep hills.

"There are a lot of issues around erosion in the wet season and lack of water in the dry season, access to market and trying to get the passionfruit down the mountain, especially in the wet season. So there are quite a few challenges.

"And then you go down to Gia Lai and they are still small holder farmers, but slightly larger farms, more undulating, easier access, deeper and more fertile soils with high yield opportunities - but also constraints as well."

Montgomery said agriculture could have negative environmental impacts at times, but it was about striking a balance of protecting the natural resource while optimising food production and food security.

"There's a balance there and it does change from system to system. In some of these areas, we do have large erosion issues which result from cropping the land and having soil exposed, so that is a negative impact of agriculture. But we do try to minimise and mitigate against that by having cover cropping, so the ground cover is really important."

She said there were knowledge gaps around nutrient and water use for some farmers in the two provinces.

"They either haven't learned about them or haven't had as much access to the knowledge about them as say we have in New Zealand and other areas. So it is a good knowledge base to start from and have a discussion about."

Montgomery said there was willingness among Vietnamese farmers to be involved with their innovation groups and the wider project, many of whom were struggling with plant disease.

"[Passionfruit] is an important fit in the farming system [in Vietnam] and there's definite interest in helping to optimise the production that comes from it," she said.

"It of course has competition in the farming system from other high-value products, such as durian which is the king fruit, coffee and other things, but it's often intercropped.

"I think the farmers are looking for answers as well because the virus is quite crippling in these vines."

The Plant and Food Research team assesses fruit quality in Vietnam.

The Plant and Food Research team assesses fruit quality in Vietnam. Photo: SUPPLIED/P&FR

She said the plant science team will regularly report back to the project's partners and check in with farmers on any progress once they adopted new practices.

"You get that local lens that gives you the real practicality and truth of the matter, and then you work together from there to see what solutions we can devise together.

"So it's going well, but we've got a lot of work still to do."

Montgomery said the next milestone will be trialling new passionfruit washer prototypes currently being engineered.

She will return to Vietnam in the coming months to progress work on the ASEAN climate smart working group.

Plant and Food Research worked with SOFRI from 2013 on a similar project, supported by the Ministry of Foreign Affairs and Trade (between 2013-2021), to develop and breed new cultivars to increase the value of dragonfruit, its largest horticultural export.

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