That botanist is Associate Prof Paul Guy and his research focuses on the impact of exotic viruses spreading to many New Zealand native and endemic plants, sometimes with damaging effects.
Prof Guy points out that much of the discussion about damaging plant diseases in New Zealand has focused on commercial crops, including the devastating Psa disease which has already caused damage amounting to hundreds of million of dollars to the country's kiwifruit industry.
Also hitting the headlines has been the recent outbreak of Queensland fruit fly in Auckland.
Few researchers have been working on the effect of exotic plant viruses on New Zealand's native plants, but Prof Guy argues this deserves more attention.
And he mentions his research involving the attractive, spring-flowering native vine, Clematis paniculata.
He visited four sites near Dunedin, including Leith Saddle, Pigeon Flat and Waitati, and found that some plants (about 4% of those tested) were infected with an exotic plant virus, Cucumber mosaic virus.
When he went back to the sites within a couple of years, the infected plants were dying.
Prof Guy is not suggesting this plant species itself is threatened by the virus, but he is highlighting the potential impact of such viruses.
And he has also found exotic virus infection in many other plants, including red tussock.
What is the appeal of being a kind of plant virus detective?
''It's a bit like hunting and collecting. It's great to come across new things that other people haven't noticed before.''
''I'm fascinated by a group of about 2000 viruses which infect plants.
''I'm interested in their interactions with agricultural and native plants.
''Because they hijack their host's metabolic machinery, their effects can range from large-scale crop failure to subtle and even appealing changes in flower and leaf colour.
''I feel like a modern day hunter and collector: my trophies are smaller than the shortest wavelength of visible light.''
''I just think we've got to take it [the virus threat] seriously and work out what's going on.''
Australian-born, Prof Guy grew up in Sydney and ''wanted to be a scientist from age 8''.
''I started out collecting rocks and minerals. My family moved up the Blue Mountains when I was 12, which is where I became interested in plants,'' he adds.
When he wants to relax, he works on the family lifestyle block at Waitati.
And he plays guitar for Dunedin musical group the Wharf Street Band, and sings with the Waitati Warblers.
Prof Guy points out that the ''real problem'' with the effect of exotic viruses on native plants was that their ''full impact'' was not yet known.
But what is already known is clearly cause for concern.
He has two key messages: one is about border security, and the other is about exotic weed control in areas with native plants.
The TVNZ television programme Border Patrol made it plain that some people arriving in this country were not voluntarily complying with our biosecurity controls.
Prof Guy favours returning to previous, stricter border controls, with all luggage being subject to X-ray screening at the border to detect fruit, food or plant material that is not being declared.
And he also highlights the importance of raising overall public awareness about the need for stricter biosecurity.
''The most critical thing is how to get to people who don't think its important''.
Stricter and more effective border controls would also indirectly help to protect New Zealand's native plants as well as exotic plants, he points out.
Prof Guy also highlights the need to maintain and improve exotic weed control in native plant areas.
Rye grass, for example, could act as a reservoir of plant viruses, when it spread into areas of native grasses.
A 2009 research article, co-authored by Prof Guy, noted that a previous study had found barley yellow dwarf viruses in nine of 24 native grass species tested.
Exotic aphids were often a key factor, acting like ''flying hypodermic syringes'', and effectively injecting viruses into native plants when the aphids bit into them, Prof Guy added.
''This study provides evidence for the invasion of native species by exotic viruses.''
The study noted that seven species of New Zealand's native grasses were ''recorded as new hosts for at least one introduced virus, providing evidence of frequent and multiple introduction events of cereal and pasture viruses''.
The paper also pointed out that the impact of such infection could be indirect, predisposing infected plants to environmental stress and reducing their ability to compete with exotic species, ''therefore affecting their survival over time''.
Prof Guy noted that virus-infected native plants, including native grasses, were often symptomless, or displaying ''mild symptoms'' in the wild.
But the indirect effect of exotic viruses could make it harder for native grasses to resist aggressive invasions by exotic weeds.
New Zealand's native and endemic plant life was a key part of its distinctiveness as a country and ''we should be looking after it'', he said.
And such plants are also a key part of what overseas tourists find attractive about this country.
One plant Prof Guy knows a lot about is quinoa, which has been been a vital part of the Andean diet since at least 3000BC.
The Incas had used it as a cereal and for breads.
Quinoa was high in protein and, unlike other grains, was not from the grass family, so was gluten free.
In recent years, Prof Guy has been advocating for greater awareness and use of quinoa as a lucrative and nutritious alternative to current grain crops.
He had visited schools in the Otago Enviroschools programme to support the growing of quinoa.
And quinoa's natural defence system against plant pests - soap-like substances on the seeds - also reduced the need for pesticides.
He also uses the plant as a ''viral indicator'' in his research work involving native plants, utilising the extensive knowledge gained by scientists over the years about which known viruses infect quinoa and which do not.
As a plant pathologist, he advocates having a diversity of crops, ''rather than the current monoculture''.
''Quinoa doesn't suffer from the same diseases that affect cereals, so it is good insurance to diversify,'' he says.
SNAPSHOT
Name and age: Paul Guy (59)
Occupation: Associate professor and plant pathologist, University of Otago botany department.
Qualifications: Include PhD from Australian National University.
Short work history: Includes Australian Wool Corp Research Fellow, Dept Primary Industries Hobart; Otago University since 1992.
Proudest achievement: Helping my wife Jen raise our two daughters, Nell and Rose.
THE CHALLENGE
INVESTIGATING BIOSECURITY CONCERNS OVER THE SPREAD OF VIRUSES FROM EXOTIC PLANTS INTO NATIVE PLANTS.
What is your research about?
Identifying viruses, from exotic plants, that infect New Zealand's native and endemic plants.
Why is it important?
Because of the impact of introduced viruses on our native flora.
Most interesting aspect of your research?
It's a bit like a detective story. You come across something that's a bit of a puzzle and you just want to work out what's going on.
In what way is it unique?
Few researchers have studied the effect of introduced viruses on New Zealand's native plants or, in other countries, on their respective native plants.
