ARGONAUTE4 and the DNA demethylase REPRESSOR OF SILENCING 1C mediate dehydroascorbate-induced intergenerational nematode resistance in rice.

Plants can transmit information to the next generation and modulate the phenotype of their offspring through epigenetic mechanisms. In this study, we demonstrate the activation of "intergenerational acquired resistance" (IAR) in the progeny of rice (Oryza sativa) plants exogenously treated with dehydroascorbate (DHA). The offspring of lifelong DHA-treated plants (DHA-IAR) were significantly less susceptible to the root-knot nematode Meloidogyne graminicola and partially inherited the DHA-induced transcriptional response found in the parental plants.

Potential of Exogenous Treatment with Dehydroascorbate to Control Root-knot Nematode Infection in Rice.

Induced resistance (IR) is a unique physiological state characterized by reduced plant susceptibility to (a)biotic stress. Our previous studies showed that exogenous foliar application of dehydroascorbate (DHA), the oxidized form of ascorbic acid, induces systemic resistance against root-knot nematode Meloidogyne graminicola in rice. In the present study, the potential of DHA in protecting rice plants against M.

Distinct chemical resistance-inducing stimuli result in common transcriptional, metabolic, and nematode community signatures in rice root and rhizosphere.

Induced resistance (IR), a phenotypic state induced by an exogenous stimulus and characterized by enhanced resistance to future (a)biotic challenge, is an important component of plant immunity. Numerous IR-inducing stimuli have been described in various plant species, but relatively little is known about 'core' systemic responses shared by these distinct IR stimuli and the effects of IR on plant-associated microbiota. In this study, rice (Oryza sativa) leaves were treated with four distinct IR stimuli (β-aminobutyric acid, acibenzolar-S-methyl, dehydroascorbic acid, and piperonylic acid) capable of inducing systemic IR against the root-knot nematode Meloidogyne graminicola and evaluated their effect on the root transcriptome and exudome, and root-associated nematode communities.

Dehydroascorbate induces plant resistance in rice against root-knot nematode Meloidogyne graminicola.

Ascorbic acid (AsA) is an important antioxidant in plants and regulates various physiological processes. In this study, we show that exogenous treatments with the oxidized form of AsA, that is, dehydroascorbate (DHA), activates induced systemic resistance in rice against the root-knot nematode Meloidogyne graminicola, and investigate the molecular and biochemical mechanisms underlying this phenotype. Detailed transcriptome analysis on roots of rice plants showed an early and robust transcriptional response on foliar DHA treatment, with induction of several genes related to plant stress responses, immunity, antioxidant activity, and secondary metabolism already at 1 day after treatment.

Rice diterpenoid phytoalexins are involved in defence against parasitic nematodes and shape rhizosphere nematode communities.

Rice diterpenoid phytoalexins (DPs) are secondary metabolites with a well known role in resistance to foliar pathogens. As DPs are also known to be produced and exuded by rice roots, we hypothesised that they might play an important role in plant-nematode interactions, and particularly in defence against phytoparasitic nematodes. We used transcriptome analysis on rice roots to analyse the effect of infection by the root-knot nematode Meloidogyne graminicola or treatment with resistance-inducing chemical stimuli on DP biosynthesis genes, and assessed the susceptibility of mutant rice lines impaired in DP biosynthesis to M.