New Zealand

Kiwi scientist finds way to counter mealybug threat

By RJ Whitehead

- Last updated on GMT

White mealybugs strike fear in the hearts of winegrowers
White mealybugs strike fear in the hearts of winegrowers

Related tags New zealand Wine

The New Zealand wine industry is now better equipped to battle a devastating plant pathogen thanks to new research carried out in the country.

Economic losses from Grapevine leafroll-associated virus 3 total tens of millions of dollars each year in New Zealand alone. 

The virus is transmitted by insects called mealybugs, which spread the disease while feeding on grapevines. Leafroll 3 reduces grapes’ sugar content, flavour and yields—particularly for premium red-grape varieties such as Pinot Noir.

There is no cure for the virus and once infected, vines eventually succumb to the disease, leaving growers with no option but to remove them and replant entire vineyards at considerable expense.

Going rogue

But now Vaughn Bell, a scientist with the New Zealand Institute for Plant & Food Research, has shown that the virus can be accurately diagnosed by visual assessment on red varieties. Growers can then remove individual infected vines annually—a process known as “roguing​”.

The research has also demonstrated that only infected vines need to be removed, not the healthy nearest neighbouring vines as well, as was previously assumed. In addition, Bell’s work has added much-needed clarity to the relationship between the disease and the mealybugs that carry it.

The complete elimination of mealybugs from vineyards is not needed and would probably be impossible​,” said Bell. “But to control the virus, we do need low population densities of vectors. So growers must not only manage their infected vines, but also the mealybug populations in their vineyards​.”

For the past five years, Bell has been a key team member of a New Zealand Winegrowers’ project that is tackling both leafroll 3 and mealybugs in participating vineyards.

The project extends over Hawke’s Bay, Wairarapa and Marlborough—all prime vinelands. Using protocols that incorporate findings from Bell’s research, many vineyard managers have been able to reduce disease incidence to less than 1%, improving the longevity and economic viability of their vineyards.

White grapes next

Vaughn’s work has helped halt the spread of leafroll 3 within New Zealand vineyards​,” says Dr Simon Hooker, research general manager at New Zealand Winegrowers. 

His ongoing engagement with the sector has also helped generate greater awareness among growers about the disease and the role played by mealybugs​.”

However, Bell said his work on finding ways to reduce the impact of leafroll 3 is far from over: “We've developed what seems to be an effective virus management programme in red-grape varieties. The next challenge is to do the same for the vines of white grape varieties which, when virus-infected, lack the visual symptoms​.”

Related topics Policy Oceania Beverages

Related news

Related products

Analyzing the unknown threat from Microplastics

Analyzing the unknown threat from Microplastics

Content provided by Agilent Technologies | 06-Nov-2023 | Infographic

Microplastics are any plastic-derived synthetic solid particle or polymeric matrix, ranging in size from 1 µm to 5 mm and insoluble in water.

Mastering taste challenges in good-for-you products

Mastering taste challenges in good-for-you products

Content provided by Symrise | 12-Sep-2023 | White Paper

When food and beverage manufacturers reduce sugar, salt, or fat and add fibers, minerals or vitamins, good-for-you products can suffer from undesirable...

Functional Beverage Market Insights in ASPAC

Functional Beverage Market Insights in ASPAC

Content provided by Glanbia Nutritionals | 06-Jul-2023 | Product Brochure

High growth ahead for protein beverages makes Asia Pacific (ASPAC) the market to watch. Consumer research shows new usage occasions, key consumption barriers,...

The latest plant-based beverage trends in SEA

The latest plant-based beverage trends in SEA

Content provided by Tetra Pak | 27-Mar-2023 | White Paper

Data shows that consumers’ liking and thirst for plant-based beverages is growing rapidly, especially in Malaysia, Singapore, Philippines and Indonesia....

2 comments

mealy bugs

Posted by jo,

you are right Roger -- a preditor not a mealybug. v.bell--- nice using reachers that was done in an African country on mealy bug control in vines

Report abuse

Mealybugs and ladybugs

Posted by Rodger,

This looks very similar to a beneficial Mealy bug destroyer, Cryptolaemus spp. which is a ladybug or ladybird.

Report abuse

Follow us

Products

View more

Food & Beverage Trailblazers

F&B Trailblazers Podcast