The native strain Paenibacillus sp. A224 mitigates stress caused by high temperatures and by the pathogen Sclerotium rolfsii in peanut plants by inducing systemic tolerance

FIGUEREDO, MARÍA SOLEDAD; ÁLAMO, TAMARA; TONELLI, MARÍA LAURA; FABRA, ADRIANA

PLANT AND SOIL

SPRINGER

Lugar: Berlin; Año: 2023

0032-079X

Background and Aim Models predicting climatechange suggest that the frequency of occurrenceof combined biotic and abiotic stresses is likely toincrease in the future. Plant growth promoting bacteria increase the defensive response of plants againstthese stresses. The main objective of this study wasto identify, in the available collection of bacteria isolated from the peanut rhizosphere or phyllosphere,those whose inoculation protects against the efects ofboth high temperature (35 °C for 6 days) and Sclerotium rolfsii occurring simultaneously through inducedsystemic tolerance (IST).Methods The trials were carried out in pots containing a peanut plant growing under optimal conditionsor under combined biotic and abiotic stress (high temperatures and Sclerotium rolfsii). Ninenative bacterial strains were tested to mitigate stress caused bysuch combined stressors by IST. Finally, systemicprotection was confrmed by quantifying biochemicalmarkers of plant defense.Results The native strain Paenibacillus sp. A224was able to reverse the deleterious efect of bothstresses on the growth and health of peanut plants.Furthermore, peroxidase activity and phenolic compound content were induced earlier in plants inoculated with Paenibacillus sp. A224 than in uninoculated ones exposed to both stresses, in concordancewith their higher tolerance to S. rolfsii and hightemperature.Conclusion The results indicate that inoculation ofPaenibacillus sp. A224 could be a useful strategy toincrease peanut tolerance against biotic and abioticstresses that occur simultaneously, through a mechanism that involves the induction of systemic defenseresponses.