Bioncontrol of wheat against Septoria Tritici Blotch: new elicitors

Wheat is one of the most cultivated crop plants in the world. However, this plant must constantly face numerous biotic challenges, including major yield losses every year (up to 30-50%) due to a foliar disease known as Septoria Tritici Blotch (STB). This persistent and harmful disease is caused by the fungus Zymoseptoria tritici. Disease control mainly depends on phytosanitary products. However, conventional agriculture is evolving towards more sustainable practices, out of respect for human health and the environment. Elicitors are considered as promising biological control tools for Integrated Plant Management (IPM) strategies. Contrary to conventional products, these natural compounds do not inhibit directly the pathogen but induce a general and systemic resistance in the plant to a large spectrum of diseases. The natural defense mechanisms of the plant are thus stimulated.
Few elicitors have yet been successfully tested and formulated to protect wheat against STB. This study focuses on the screening of ten potential elicitor products of various origins and structures to protect winter wheat against Zymoseptoria tritici. Greenhouse trials were carried out to measure the ability of the different products to reduce disease foliar symptoms (necrosis, chlorosis and pycnidia). In addition, the biocide activity of these products directly towards the pathogen was evaluated under greenhouse and laboratory conditions, respectively. The corresponding results will be presented and discussed with the perspective to choose the best elicitor candidates for field trials and to undertake further investigations on the signaling pathways, and the influence of environmental parameters, on the elicitation capacity.