Dr. Samuel Gan-Mor has developed a blend of edible oils that can be sprayed once a week to keep insects and fungi from munching on tomatoes, zucchini peppers, and grains. Dr Gan-Mor works at the Israel Ministry of Agriculture’s research centre at the Volcani Institute.
http://www.israeltrade.org.au/israels-oily-approach-to-natural-pest-control/