Soil amendment with halophytes induces physiological changes and reduces root-knot infection in eggplant and okra

Abstract

Root-knot nematode, Meloidogyne javanica (Treub) Chitwood is a soil-borne plant pathogen of roots. Nematode infection results in altered plant growth and physicochemical processes due to gall formation. Many plants contain unique biochemicals that have biocidal properties and offer a potential novel approach to suppress the nematode populations in soil and improve growth of crop plants. In the present study effect of some indigenous halophytic plant species (Tamarix indica Willd, Suaeda fruticosa Forssk and Salsola imbricata (Schultz) Dandy) were tested against M. javanica. Tested halophytes significantly (P<0.001) reduced egg hatching and caused mortality of second stage juveniles (J₂) in vitro. These halophytes when incorporated in soil (0.3, 0.5 and 1% w/w) markedly increased growth of eggplant (Solanum melongena L. cv. Black beauty) and okra (Abelmoschus esculentus [L.] Moench. cv. Arka anamika) and provided control of root-knot infection at higher doses (0.5 and 1%). Amended eggplants and okra showed significant (P<0.001) increase in chlorophylls and decrease in chlorophyll a/b ratio. Protein concentration in leaves of both the plants were increased with 1% amendment of S. fruticosa and S. imbricata. While nucleic acid concentrations were varied with different treatments.