Red Light-Induced Systemic Resistance to Root knot Nematodes in Tomato

Abstract

This study was conducted to evaluate efficiency of red light to induce systemic resistance in tomato plants grown in 1kg plastic pots under green house conditions against Meloidogyne spp. Results indicated that tomato seedlings exposed to red light for 2 and 3wks were significantly (p=0.05) more resistant to the root knot nematodes than seedlings exposed to white light (control seedlings). This was manifested by the less number of galls on the roots of treated compared with control plants 30d after inoculation. Root gall index(gi) was 2.77 for red  light treated and 5 for control plants. Root fresh and dry weight was 5.00 and 0.39 g for red light treatment compared with 6.31 and 0.64 g for white light control treatment respectively. Significantly (p=0.05) less (55) second stage juveniles (J2) enter the roots of red light treated plants compared to 123.66 J2 in control.

Keywords: Induced  resistance, Meloidogyne spp, Red light, Tomato.