During outbreaks, gregarious locusts may spread over an enormous area, in particular in Africa, the Near East, Middle East, Far East, South-West Asia, North and South America and Australia. Traditionally chemical pesticides are used to control the outbreak of gregarious locusts in the field. However, in recent years chemical pesticides were discredited because of their negative effects on human health and harmful side effects on the ecosystem. In recent decades, the public awareness about the amount of residual chemicals that persist in food, ground water and the environment increased.
As a possible alternative to chemical pesticides, fungi targeting certain insect species were proposed by FAO (Food and agriculture organization) researchers and the WHO (world health organization). Major drawbacks of using this fungus for the control of locusts come with the laboratory equipment that is necessary to check for the biological activity of the fungus and to prepare the solution for the aerosol treatment. Another drawback of this fungus treatment comes with the time it takes to grow and harm infested locusts (about two weeks).
Control the outbreak of gregarious locusts in the field by using an innovative oil emulsion.
In a recent invention of the Uni Graz vegetable oils and several essential oils were mixed to create a formulation that harms all developmental stages of locusts after fumigant treatment. In contrast, mealworm beetles treated in the same way were still alive and behaved normally. The innovative oil emulsion consists of an aqueous solution of hydrogencarbonate, linseed oil (made from flax Linum usitatissimum), caraway oil (from Carum carvi), orange peel oil and wintergreen oil (Gaultheria procumbens). After fumigant treatment more than 95% of locust individuals died within 24 hours and then the oil can be removed from the vegetation by means of an environmental friendly washing solution.