Pinus radiata is Australia’s most valuable softwood resource and extremely susceptible to mortality from pest Sirex – a wood wasp known to attack pine trees, and the most serious invasive softwood pest in the Southern Hemisphere.
In great news for pine growers in Australia, the discovery of a new type of nematode (often referred to as roundworm) could hold the key to overcoming the devastation that Sirex noctilio can inflict on pine plantations.
Australia pioneered the main Sirex management technique now used globally: vaccinating infested trees with the very small, slender worm-like nematodes. The nematodes feed on the Sirex fungus, infest its larvae and sterilise emerging females.
Research at the Forest and Biotechnology Institute (FABI) in South Africa, funded by the National Sirex Coordination Committee (NSCC), unexpectedly uncovered a previously unknown strain of nematode that is genetically distinct from the Kamona strain traditionally used to combat Sirex infestation.
Recent research supported by FWPA, NSCC, FABI, the Queensland and New South Wales governments, and the University of the Sunshine Coast, found that this new strain, known as ‘Lineage D’, has a faster reproductive rate, proven field persistence and broader genetic diversity than the Kamona strain. Importantly, it can also sterilise Sirex eggs.
The new strain is expected to be introduced into Sirex biocontrol programs over the next few years, with the traditional Kamona strain phased out.
Two of the researchers involved in the discovery of Lineage D, Dr Helen Nahrung, University of the Sunshine Coast, and Dr Angus Carnegie, NSW Department of Primary Industries, are organising a satellite Sirex management meeting to discuss their findings at the IUFRO Forest Health in Southern Hemisphere Commercial Plantations meeting to be held in Brazil this September.
“We are delighted that this work has resulted in such an unexpected, hugely significant discovery prompting a global conversation about Sirex biocontrol approaches and how they may be improved with the use of this newly discovered strain,” Dr Nahrung said.
Source: Forest & Wood Products Australia