Combined effect of β-aminobutyric acid and silver nanoparticles on eggplants, Solanum melongena, infected with Meloidogyne javanica

Abstract

Summary The acquired resistance of plants to root-knot nematodes (Meloidogyne spp.) can be achieved by applying chemical inducers, such as β-aminobutyric acid (BABA). Recently, the use of metal nanoparticles with multifunctional use against plant-parasitic nematodes has been presented. In this study, silver nanoparticles (AgNPs) were synthesised using the aqueous leaf extract of Malva sylvestris. The effect of different AgNPs concentrations on hatching and mortality of the second-stage juveniles (J2) of Meloidogyne javanica was investigated in vitro. The effects of AgNPs on eggplants infected with 0, 1, 2, 4 and 8 eggs (cm3 soil)−1 were investigated under glasshouse conditions. The combined effects of AgNPs and BABA on eggplants infected with 4 and 8 eggs (cm3 soil)−1 were investigated in another study. The results showed that increasing the concentration of AgNPs the hatching of M. javanica decreased and the mortality of J2 increased. The number of eggs, galls, egg masses and reproduction factor in plants treated with AgNPs infected with 4 eggs (cm3 soil)−1 decreased by 43.4, 24.7, 23.5 and 43.2%, and in plants infected with 8 eggs (cm3 soil)−1, decreased by 64.5, 25.5, 63.1 and 64.5%, respectively, compared to control plants. The reproduction factor in infected plants with 4 and 8 eggs (cm3 soil)−1 that were treated with BABA (1 mM) and AgNPs decreased by 51.6 and 55.9%, respectively, compared to control plants. The results of this study demonstrated the effects of BABA, AgNPs and the combination of these two substances in reducing the damage of different inoculum densities of M. javanica in eggplant.