Phytophthora capsici is a highly destructive pathogen of crops. Although chemical pesticides are the most widely used strategy to counter phytopathogens, they have been inefficient to combat P. ...capsici and have produced significant environmental and health problems. Therefore, sustainable alternatives to control soilborne pathogens, such as the inhibitory effect of self‐extracellular DNA (eDNA), have been proposed. This inhibition phenomenon has been attributed to the action of self‐eDNA as a damage‐associated molecular pattern (DAMP). Here, we describe the effect of self‐eDNA on P. capsici zoospore germination rate, antioxidant enzymes activity and MAPK gene expression. Also, the effect of P. capsici eDNA on the protection of chilli pepper (Capsicum annuum) plants against P. capsici was investigated. The results highlight that P. capsici can sense 2–500 µg/ml self‐eDNA and induce stress‐related responses like SAK1 gene expression, and superoxide dismutase and catalase activities. Moreover, in vitro zoospore germination rate was suppressed with self‐eDNA concentrations ranging from 50 to 500 µg/ml. Interestingly, drench applications of P. capsici eDNA at 60 and 100 µg/ml on chilli pepper plants did not show any protective effect against the phytopathogen, whereas 2 µg/ml of P. capsici eDNA drench application showed a lower percentage of plants with symptoms and lower disease severity. Moreover, phenols and total flavonoids were increased in chilli pepper plants, therefore inducing plant immunity. This study showed that self‐eDNA acts as a DAMP in P. capsici and provides insight into the use of eDNA for the protection of crops of agronomic interest.
This study showed that self‐eDNA acts as a DAMP in P. capsici inducing stress‐related responses, giving an insight into the use of self‐eDNA in field‐like conditions against the phytopathogen.
Current research in basic and applied knowledge of plant science has aimed to unravel the role of the interaction between environmental factors and the genome in the physiology of plants to confer ...the ability to overcome challenges in a climate change scenario. Evidence shows that factors causing environmental stress (stressors), whether of biological, chemical, or physical origin, induce eustressing or distressing effects in plants depending on the dose. The latter suggests the induction of the “hormesis” phenomenon. Sustainable crop production requires a better understanding of hormesis, its basic concepts, and the input variables to make its management feasible. This implies that acknowledging hormesis in plant research could allow specifying beneficial effects to effectively manage environmental stressors according to cultivation goals. Several factors have been useful in this regard, which at low doses show beneficial eustressing effects (biostimulant/elicitor), while at higher doses, they show distressing toxic effects. These insights highlight biostimulants/elicitors as tools to be included in integrated crop management strategies for reaching sustainability in plant science and agricultural studies. In addition, compelling evidence on the inheritance of elicited traits in plants unfolds the possibility of implementing stressors as a tool in plant breeding.
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•A big challenge in current plant production is to cope with climate change.•Environmental hormesis must be included in plant science research.•Plant biostimulants/elicitors are current agrochemicals sometimes displaying hormesis.•Controlled elicitation strategies including hormetic scenarios must be designed.•Plant biostimulation using controlled management of stressors is proposed as a tool for sustainable agriculture.
Epigenetic regulation is a key component of stress responses, acclimatization and adaptation processes in plants. DNA methylation is a stable mark plausible for the inheritance of epigenetic traits, ...such that it is a potential scheme for plant breeding. However, the effect of modulators of stress responses, as hydrogen peroxide (H
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), in the methylome status has not been elucidated. A transgenic tobacco model to the
gene displayed high H
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endogen levels correlated with biotic and abiotic stresses resistance. The present study aimed to determine the DNA methylation status changes in the transgenic model to obtain more information about the molecular mechanism involved in resistance phenotypes. The Whole-genome bisulfite sequencing analysis revealed a minimal impact of overall levels and distribution of methylation. A total of 9432 differential methylated sites were identified in distinct genome regions, most of them in CHG context, with a trend to hypomethylation. Of these, 1117 sites corresponded to genes, from which 83 were also differentially expressed in the plants. Several genes were associated with respiration, energy, and calcium signaling. The data obtained highlighted the relevance of the H
O
in the homeostasis of the system in stress conditions, affecting at methylation level and suggesting an association of the H
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in the physiological adaptation to stress functional linkages may be regulated in part by DNA methylation.
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