COMERCIALLY VIABLE BIOCONTROL METHODS TO COMBAT INSECT PESTS
Insects cause damage totalling several billion kronor a year to harvests in Sweden. Insecticides, the chemical agents available for controlling insect pests, often have serious effects on the environment and health. Insecticides also result in resistance among insects, which further boosts the use of chemicals. Many insecticides have been banned and today only a few remain. Accordingly, the need for new methods of pest control has grown.
The Biosignal research programme brought together biologists, chemists and ecologists to develop methods of plant protection from insects’ own signal systems, using various ‘pheromones’. Starting with the world of insect scents and tastes, the researchers sought to divert the pests from the crops to be protected. Biological control (biocontrol) and forecasting methods to predict when protection is needed have been developed and are helping to bring about more sustainable use of nature for food production with lower insecticide requirements. These methods also have the advantage of not causing insect pests to develop resistance, which is otherwise a major problem in all pest control.
WHAT RESULTS HAS THE PROGRAMME HAD?
Several of the research results from the programme have been applied in sustainable, effective and economically rational methods of controlling insect pests. The work has also yielded several patents, and two companies have been started by the researchers.
‘I expect the use of pheromones for control and forecasting of insect pests to increase in the United States over the ten-year period ahead as the insecticides used to date are prohibited.’ Professor Jay F. Brunner of the Tree Fruit Research and Extension Center, Washington State University, USA
Pest control of the apple fruit moth (Argyresthia conjugella), an economically significant pest, with a pheromone technique that confuses the insects with scents proved a great success during several growing seasons in Österlen and Norrköping. The results confirm that the longer it is used and the larger the contiguous area in which it is applied, the more effective the method becomes, Moreover, unlike insecticides, the confusion method affects only the target organism and does not disturb other species in the ecosystem. In 2005, the programme registered the pheromones of the apple fruit moth with the Swedish Chemicals Agency for biocontrol in Sweden. In 2007 use of Gusathion, the most effective insecticide against this pest, was banned. Today, the pheromone method is used in virtually all commercial orchards in Sweden. WebGIS, a database that correlates insect capture in pheromone traps with other relevant data, has been compiled for orchards in Skåne.
Delaying infestation by aphids proved feasible by means of the plant substance methyl salicyclate, which mobilises the plant’s own defences as well. This applies especially to aphids in greenhouses, but also to those that infest cereals. Methyl salicylate and another two substances are marketed under the trademark Nocoron, which is registered in Germany.
A labour-saving system for spreading various volatile compounds in greenhouses was developed. Experiments in practical cultivation have also indicated a control effect against certain sap-sucking pests known as homopterans. This may open up an entirely new market since pests in this group are very common in, for example, potato cultivation. The spin-off company Organox has been formed.
Another spin-off firm, Pheronet AB, markets part of the results from Biosignal along with results from other research activities. Through the company, the growers are being offered forecasting systems and monitoring traps for several different species of insect pest, and also dispensers for biocontrol using pheromones.
WHO HAS BENEFITED FROM THE RESEARCH?
Fruit and cereal growers, viniculturists and the milling industry in Sweden and the rest of the world benefit greatly from the results, as do the companies engaged in developing and selling biocontrol methods for these users. Besides agriculture, benefits from the research accrue to forestry and the food industry, as well as public agencies at various levels with responsibility for these livelihoods. For the public, the gain is that fewer chemicals with an environmental impact are being used in farming and dispersed further in the environment.