An in vitro approach to study oxidative stress in tomato roots during root-knot nematode infection

Root-knot nematodes (Meloidogyne spp.) are among the most economically damaging pests in agriculture, capable of severely impairing crop productivity by disrupting root function and nutrient uptake. These soil-borne phytoparasites manipulate the host plant’s root system to form specialized feeding structures, compromising plant vigor and yield. Understanding how crops respond to nematode infection at the physiological level is essential for developing effective control strategies. However, traditional field and greenhouse studies often face challenges due to environmental variability and biological complexity.

In this study, we resorted to in vitro culture systems of tomato transgenic roots to examine host responses to Meloidogyne incognita under controlled conditions. Oxidative stress markers were assessed by spectrophotometric analysis, focusing on the accumulation of thiobarbituric acid-reactive substances (TBARS), a proxy for lipid peroxidation, and the activity of the antioxidant enzyme ascorbate peroxidase (APX). Nematode-infected roots exhibited a 25% increase in APX activity, along with higher TBARS levels, indicating a noticeable oxidative response following root infection.

These results suggest that M. incognita may alter the redox status of host root tissues, reflecting both a plant defense strategy and/or nematode-induced physiological disruption. Understanding these stress pathways provides valuable insight into the mechanisms underlying crop susceptibility and resilience, offering potential targets for improving resistance and minimizing nematode-related yield losses.