A Laminarin-Based Formulation Protects Wheat Against Zymoseptoria tritici via Direct Antifungal Activity and Elicitation of Host Defense-Related Genes

Abstract

The present study aimed to evaluate the potential of the laminarin-based formulation Vacciplant® to protect and induce resistance in wheat against Zymoseptoria tritici, a major pathogen on this crop. Under greenhouse conditions, a single foliar spraying of the product two days before inoculation with Z. tritici reduced disease severity and pycnidium density by 42% and 45%, respectively. Vacciplant® exhibited a direct antifungal activity on Z. tritici conidial germination both in vitro and in planta. Moreover, it reduced in planta substomatal colonization as well as pycnidium formation on treated leaves. Molecular investigations revealed that Vacciplant® elicits but did not prime the expression of several wheat genes related to defense pathways, including phenylpropanoids (phenylalanine ammonia-lyase and chalcone synthase), octadecanoids (lipoxygenase and allene oxide synthase), and pathogenesis‐related proteins (β‐1,3‐endoglucanase and chitinase). By contrast, it did not modulate the expression of oxalate oxidase gene involved in the reactive oxygen species metabolism. UHPLC-MS analysis indicated limited changes in leaf metabolome after product application in both non-inoculated and inoculated conditions, suggesting a low metabolic cost associated with induction of plant resistance. This study provides evidence that the laminarin-based formulation confers protection to wheat against Z. tritici through direct antifungal activity and elicitation of plant defense-associated genes.

Microbial consortium mediated acceleration of the defense response in potato against Alternaria solani through prodigious inflation in phenylpropanoid derivatives and redox homeostasis

“…PR proteins are a set of novel proteins mainly produced by various plant organs in lower amounts and directly linked with host defense, which hampers the pathogen progression [ 110 , 111 ]. The two important PR proteins, β-1,3-glucanase and chitinase, belonging to the PR 2 and PR 3 families, respectively, play pivotal roles in plant resistance [ [112] , [113] , [114] ]. Saravanakumar et al [ 115 ] demonstrated that when rice plants were treated with a consortium of Pseudomonas spp., higher accumulations of chitinase were found against the sheath rot pathogen caused by Sarocladium oryzae .…”

Plant Resistance Inducers Affect Multiple Epidemiological Components of Plasmopara viticola on Grapevine Leaves

“…This prompt reaction has been linked to strong hydrogen peroxide (H 2 O 2 ) up-regulation Trouvelot, Varnier [ 31 ], [ 63 ], which could reduce stomatal opening and impair a pathogen’s penetration of the host [ 64 ]. A direct effect of LAM was found against Zymoseptoria tritici in wheat [ 65 ], but its role against P. viticola is controversial. Besrukow et al [ 66 ] observed impaired zoospore motility, and Mestre, Arista [ 67 ] identified an endo-β-1,3-glucanases able to exert a direct effect against DM, whereas Gauthier, Trouvelot [ 49 ] and Steimetz, Trouvelot [ 63 ] reported no direct effect of LAM on P. viticola .…”

Jania adhaerens Primes Tomato Seed against Soil-Borne Pathogens

“…To highlight the potential induced resistance effect by JA WSPs, treated seeds were water-washed after soaking, to remove any extract residues that could have a direct antifungal effect. Polysaccharides such as laminarin were reported to exert an antigerminative effect against the conidia of some fungi [64,65]. The polysaccharides extracted from JA might explain the elicitation of plant physiological responses against pathogens with the improvement of seedling emergence and plant growth, which may have concurred to the disease reduction.…”