Weed Biocontrol Issue 73

From the Editor

We have refreshed the look of this newsletter to bring it into line with other Landcare Research publications, but the content, style and purpose (to keep you updated and informed about weed biocontrol research) remain unchanged. This is the slightly longer issue that we produce each August. Thanks to our many loyal readers who regularly send feedback after each issue. It is always wonderful to receive this and please keep it coming. If you still receive a hard copy and are ready to make the move to an electronic version, please let me know.

Happy reading! Lynley.

In this issue

New World Biocontrol Catalogue

Recently an international team of researchers, led by Rachel Winston, has undertaken a major revision and expansion of this catalogue, which now includes 224 weeds and 552 agents.

Green thistle beetle (Cassida rubiginosa).

Biocontrol agents released in 2014/15

125 biocontrol agents were released in 2014/15.

Lesser calamint growing wild and unwanted in Hawke’s Bay. Image - Darin Underhill

Herb Invasion in Hawke’s Bay

Lesser calamint (Calamintha nepeta) is now a target on Landcare Research’s weed radar.

Two New ‘World-First’ Agents Ready for Combat

Two new biocontrol agents have recently been approved for release: the privet lace bug (Leptoypha hospita) and the Japanese honeysuckle stem beetle (Oberea shirahatai).

Possible symbiotic microorganism within smeared tissue of a green thistle beetle larva (400x magnification). Image - Darwin Hickman.

What’s Bugging Our Bugs?

One possible reason for weed biocontrol agents underperforming post release is the presence of unwanted microorganisms that infect the gut and other organs. In New Zealand it has been standard practice since 1984 to routinely screen all biocontrol agents for pathogens before release, but until recently there has been no follow-up research into how effective this screening has been.