A Plant Nutrient- and Microbial Protein-Based Resistance Inducer Elicits Wheat Cultivar-Dependent Resistance Against Zymoseptoria tritici

• Published in: Phytopathology Vol. 109; no. 12; pp. 2033 - 2045
• Main Authors: Ors, M, Randoux, B, Siah, A, Couleaud, G, Maumené, C, Sahmer, K, Reignault, P, Halama, P, Selim, S
• Format: Journal Article
• Language: English
• Published: United States American Phytopathological Society 01.12.2019
• Subjects: Ascomycota - physiology; Disease Resistance - drug effects; Fertilizers; Fungicides, Industrial; Life Sciences; Nutrients - pharmacology; Plant Diseases - microbiology; Triticum - drug effects; Triticum - microbiology; Vegetal Biology; wheat; Zymoseptoria tritici; induced resistance; manganese; defense mechanisms; Zymoseptoria tritic
• ISSN: 0031-949X; 1943-7684; 0031-949X
• DOI: 10.1094/PHYTO-03-19-0075-R

The induction of plant defense mechanisms by resistance inducers is an attractive and innovative alternative to reduce the use of fungicides on wheat against , the responsible agent of Septoria tritici blotch (STB). Under controlled conditions, we investigated the resistance induction in three wheat cultivars with different susceptible levels to STB as a response to a treatment with a sulfur, manganese sulfate, and protein-based resistance inducer (NECTAR Céréales). While no direct antigermination effect of the product was observed in planta, more than 50% reduction of both symptoms and sporulation were recorded on the three tested cultivars. However, an impact of the wheat genotype on resistance induction was highlighted, which affects host penetration, cell colonization, and the production of cell-wall degrading enzymes by the fungus. Moreover, in the most susceptible cultivar Alixan, the product upregulated , , , and gene expression in both noninoculated and inoculated plants and in noninoculated plants only. In contrast, defense responses induced in Altigo, the most resistant cultivar, seem to be more specifically mediated by the phenylpropanoid pathway in noninoculated as well as inoculated plants, since and were most specifically upregulated in this cultivar. In Premio, the moderate resistant cultivar, NECTAR Céréales elicits mainly the octadecanoid pathway, and induction in noninoculated plants. We concluded that this complex resistance-inducing product protects wheat against by stimulating the cultivar-dependent plant defense mechanisms.