Imported plant disease first used in war on weeds: New Zealand scientists

New Zealand scientists are claiming a world first in using South American plant diseases to control a notorious weed.

The government's Landcare Research institute said Wednesday it had released the Peruvian disease, lantana blister rust, in the eastern North Island in a bid to control lantana, considered one of the world's 10 worst weeds.

Landcare Research scientists said they had been searching for biocontrols before lantana became widespread and had settled on a pathogenic fungi.

Lead researcher on the project Maj Padamsee said the emerging weed posed a serious threat to New Zealand's agricultural industry as it was extremely difficult to control once established and could easily overrun farmland.

"These releases are pre-emptive to make sure it doesn't get to that point. We're trying to nip lantana in the bud," she said in a statement.

"It's the first time the lantana blister rust has been used as a biocontrol anywhere in the world, which makes this release really exciting."

The lantana blister rust attacks the stems, leaf stalks and leaves, effectively killing the plant.

Lab technician Chantal Probst said Landcare Research imported lantana infected with the disease last year and began mass-rearing it for release.

The Brazilian plant disease, lantana leaf rust, which affects the leaves, had also recently been released.

Both plant diseases could co-exist on lantana and were expected to complement each other by having slightly different climatic requirements, Probst said in the statement. Endi