Exploring levan oligosaccharide-producing organisms to protect strawberry fruit

Novel approaches to develop alternatives for the use of  agrochemicals, e.g. fungicides, are urgently needed. Application of biocontrol microorganisms and natural compounds leads to more sustainable and environmentally friendly disease-control on important crops. Strawberry is a highly popular small fruit crop worldwide with a significant economic importance and a large market share in Europe. In Estonia and Belgium strawberry is the most important berry crop which is produced and exported increasingly. Diseases caused by fungal pathogens on strawberry plants are causing tremendous economic loss worldwide, especially in humid conditions. The aim of the project is to incorporate the expertise of research groups in KU Leuven and University of Tartu for exploration and initial screening of microbial communities and selected microorganisms in combination with levan oligosaccharides (LOS) in order to protect strawberry from fungal infection. It has been recently proven that fructans (incl. levan) boost plant innate immunity. In this project, culture-based approaches will be applied to get an insight of the potential LOS-producing bacteria and their significance in strawberry to protect the fruit against grey mold (Botrytis cinerea). The effect of the treatments with selected bacteria and levan-type saccharides during the fruit production and postharvest stages will be evaluated. As an outcome of this project some of the fundamental concepts for future European collaboration projects focusing on sustainable solutions for plant health and the improvement of product quality will be verified. Insights in structure-function relationships of levan-degrading enzymes will offer a great potential for novel enzyme design-based applications which are in line with future plant and animal disease prevention strategies.