0000000000294212
AUTHOR
Victor Flors
Effect of a novel chemical mixture on senescence processes and plant--fungus interaction in Solanaceae plants.
The effects of exogenous application of a chemical mixture consisting of adipic acid monoethyl ester, furfurylamine, and 1,2,3,4-tetra-O-acetyl-beta-D-glucopyranose (FGA) on various metabolic pathways and the plant-fungus interaction have been studied in Solanaceae plants. Tomato and pepper plants were sprayed with the FGA mixture, and different biochemical parameters such as gas exchange, chlorophyll concentration, protein, cell wall sugar and phenolics contents, and peroxidase and phenylalanine ammonia lyase (PAL) activities were measured. FGA-treated plants showed, in general, an increase in cell wall sugar content and decreases in the chlorophyll degrading rate and the peroxidase activi…
Preventive and post-infection control ofBotrytis cinereain tomato plants by hexanoic acid
The antifungal activity of hexanoic acid on the phytopathogen Botrytis cinerea was studied. This chemical inhibited both spore germination and mycelial growth in vitro in a concentration- and pH-dependent manner, and stopped spore germination at a very early stage, preventing germ-tube development. The minimum fungicidal concentration (MFC) for in vitro spore germination was 16 m m . Hexanoic acid also inhibited in vitro mycelial growth of germinated spores at an MFC of 12 m m . Studies performed to characterize the mechanisms underlying the antimicrobial effect of hexanoic acid showed that it alters fungal membrane permeability. In addition, hexanoic acid treatment increased the levels of …
Priming for JA-dependent defenses using hexanoic acid is an effective mechanism to protect Arabidopsis against B. cinerea
Abstract Soil drench treatments with hexanoic acid can effectively protect Arabidopsis plants against Botrytis cinerea through a mechanism based on a stronger and faster accumulation of JA-dependent defenses. Plants impaired in ethylene, salicylic acid, abscisic acid or glutathion pathways showed intact protection by hexanoic acid upon B. cinerea infection. Accordingly, no significant changes in the SA marker gene PR-1 in either the SA or ABA hormone balance were observed in the infected and treated plants. In contrast, the JA signaling pathway showed dramatic changes after hexanoic acid treatment, mainly when the pathogen was present. The impaired JA mutants, jin1-2 and jar1 , were unable …
Mycorrhizal symbiosis primes the accumulation of antiherbivore compounds and enhances herbivore mortality in tomato
Abstract Plant association with arbuscular mycorrhizal fungi (AMF) can increase their ability to overcome multiple stresses, but their impact on plant interactions with herbivorous insects is controversial. Here we show higher mortality of the leaf-chewer Spodoptera exigua when fed on tomato plants colonized by the AMF Funneliformis mosseae, evidencing mycorrhiza-induced resistance. In search of the underlying mechanisms, an untargeted metabolomic analysis through ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS) was performed. The results showed that mycorrhizal symbiosis had a very limited impact on the leaf metabolome in the absence of stress, but significantly m…
Three novel synthetic amides of adipic acid protect Capsicum anuum plants against the necrotrophic pathogen Alternaria solani
Three novel amides of adipic acid, 5-carbamoil ethyl pentanoate (N1), 5-(2-furfurylmethylcarbamoil) ethyl pentanoate (N2) and 5-(3-aminopropylcarbamoil) ethyl pentanoate (N3) were synthesized and their resistance-inducing activity was studied on pepper (Capsicum annuum) plants. Treatment with low doses of each amide protected pepper plants against the pathogen Alternaria solani, N1 being the most effective. Although their mode of action is still unknown, prechallenge studies demonstrated the induction of the phenylpropanoid pathway and an antisenescence effect. These effects were previously shown for other mixtures and derivatives of adipic acid. These new chemicals showed no antimicrobial …
The Sulfated Laminarin Triggers a Stress Transcriptome before Priming the SA- and ROS-Dependent Defenses during Grapevine's Induced Resistance against Plasmopara viticola
Grapevine (Vitis vinifera) is susceptible to many pathogens which cause significant losses to viticulture worldwide. Chemical control is available, but agro-ecological concerns have raised interest in alternative methods, especially in triggering plant immunity by elicitor treatments. The β-glucan laminarin (Lam) and its sulfated derivative (PS3) have been previously demonstrated to induce resistance in grapevine against downy mildew (Plasmopara viticola). However, if Lam elicits classical grapevine defenses such as oxidative burst, pathogenesis-related (PR)-proteins and phytoalexin production, PS3 triggered grapevine resistance via a poorly understood priming phenomenon. The aim of this st…
Evolution de la résistance basale à Botrytis cinerea au cours de la maturation de la baie
National audience; Mature grapevine berries at the harvesting stage (MB) are very susceptible to the grey mould fungus Botrytis cinerea while veraison berries (VB) are not. We conducted simultaneous microscopic and transcriptomic analyses of the pathogen and the host to investigate the infectious process developed by B. cinerea on MB versus VB, and the plant defence mechanisms deployed to stop the fungus development. On the pathogen side, our genome-wide transcriptomic data revealed that B. cinerea genes up-regulated during infection of MB are enriched in functional categories related to necrotrophy such as degradation of plant cell wall, proteolysis, membrane transport, oxidative stress re…
Absence of the endo-beta-1,4-glucanases Cel1 and Cel2 reduces susceptibility to Botrytis cinerea in tomato.
Cel1 and Cel2 are members of the tomato (Solanum lycopersicum Mill) endo-beta-1,4-glucanase (EGase) family that may play a role in fruit ripening and organ abscission. This work demonstrates that Cel1 protein is present in other vegetative tissues and accumulates during leaf development. We recently reported the downregulation of both the Cel1 mRNA and protein upon fungal infection, suggesting the involvement of EGases in plant-pathogen interactions. This hypothesis was confirmed by assessing the resistance to Botrytis cinerea infection of transgenic plants expressing both genes in an antisense orientation (Anti-Cel1, Anti-Cel2 and Anti-Cel1-Cel2). The Anti-Cel1-Cel2 plants showed enhanced …