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. graminicola was evaluated in lab, pot, and field studies. In an experiment where the interval between foliar treatment and inoculation was varied, 20 mM DHA was found to protect rice plants from M. graminicola for at least 14 days. Pot and field studies confirmed that 10 or 20 mM DHA are highly effective in reducing gall formation and led to a significant increase…