Rothschild Prize

Shalom Applebaum

Entomology | 2010

Rothschild Prize in Agriculture

Professor Shalom Applebaum, Mauerberger Professor Emeritus in Entomology at the Faculty of Agriculture of the Hebrew University, is currently devoted to the integration of biological agents and processes in pest control. On the one hand, agrochemical companies have developed chemicals which are ‘environmentally friendlier’; on the other hand, ‘green solutions’ which rely on the controlled use of predators and parasites to destroy agricultural pests are gaining popularity. Professor Applebaum believes that in order to realistically meet the food demands of the increasing world’s population, it will be necessary to integrate biological and chemical methods.

‘It all started in our research labs about 30 years ago. We decided to investigate insect physiology with an eye towards pinpointing unique life-cycle characteristics to target as potential biocontrol agents. Our basic hypothesis was that each species of insect can be differentiated by biochemical pathways and response to environmental stimuli – biotic and abiotic, ranging from behaviour in response to environmental stress, to interactions between individuals and populations which contribute beneficially to the species. We proposed that by targeting such interactions we might be able to selectively control insect populations. This was at one time an unknown approach in Israel. The studies were initially at the interface of insect physiology, biochemistry and endocrinology in the context of fertility and development. Within this framework we came to certain innovative findings – which sometimes differed from common wisdom but were often correct'.

One of Professor Applebaum’s research subjects has been the interaction between male and female insects in night flying moths. ‘We decided to concentrate on mating behaviour and to investigate ways to interfere in this process. The potential is clear: any substance which interferes in the female’s sexual interaction with the male will reduce the species’ reproductive potential. Following up on that, we investigated male response to female sex pheromones — secreted by females when reproductively mature and receptive to mating, and which they stop releasing after mating. Depression of female pheromone release effectively prevents subsequent mating. Several potential substances which hinder pheromone production are currently being examined.

The interaction of inhibitors of chitin synthesis (CSI) and a pathogenic fungus to moth larvae is being studied. CSI interfere in the synthesis of chitin (a defensive layering on the bodies of insects) and are regarded as 'more environmentally compatible' with a minimal effect on higher animals, while the fungus has no effect on most other insects.’ This approach is one which is committed to environmental responsibility without compromising effective pest control. A combination of both is based on a strong synergism between the two components and significantly increased control efficacy, minimizing environmental damage.