The use of biological control methods using entomopathogens such as fungi is one way around the increasing pesticide resistance being developed by major crop pest insects according to Stephen Ford.
Greentide Ltd.’s managing director says chemical pesticides will always have 1-2% of insects that are tolerant of the spray. Given the rapid lifecycles of many insects, it often only takes a couple of years before an insect population is resistant to a particular concentration of chemical pesticide, forcing an ever upward ratcheting of spray quantities to achieve pest control.
However, given both legislator and public desire for less chemical pesticides, a biological control through entomopathogens is a perfect solution he says.
Comparatively speaking, an entomopathogen is like being hit by a baseball bat to the head from an insect’s point of view.
Greentide’s fungi work by a spore catching the side of an insect. It punches a hole through its exoskeleton, climbs inside and helps itself to the insect as a food source.
‘It’s very difficult to get insect resistance to a physical control,’ Ford says. ‘With a physical mechanism, there is no sub-lethal dose, and there’s been no recorded resistance.’
In addition, the fungal damage caused to the insect’s cuticle increases the penetration of natural metabolites that are part of the biological-control formulation — again hastening an insect’s death. Ford has recently been granted a world-first patent for his completely non-toxic (to humans) natural metabolite — and as its won’t become insect resistant, this patent could easily be effective for the 20 years it is granted.
As one of 10 finalists in the University of Auckland Business School’s Entrepreneurs’ Challenge, if Greentide won one of the prizes, the money would be poured into even more bioreactors to produce even more of the biological control.
Being centred in New Zealand’s main vegetable crop growing area, and now having proven that his products are consistently as insect lethal as chemical controls, Greentide’s expanding to Australia and the U.S.A, and expects to be in South Africa by July next year.
‘We’re hoping to make all the product in New Zealand, though won’t for Australia,’ Ford says. ‘Over there, they’re very parochial and we’ve been advised to have an Australian Made flag on the package.’