Effect of Ralstonia solanacearum and Meloidogyne javanica on Tomato Plant Antioxidant Activity

Meloidogyne javanica and Ralstonia solanacearum are the highly specialized soil-born plant parasites with economic importance causing root-knot and bacterial wilt diseases in tomatoes, respectively. The occurrence and intensity of the bacterial wilt escalated in the presence of root-knot nematodes and R. solanacearum concurrently detected in different vegetable crops. Sampling and preparation of leaf extract were done to investigate the activity of catalase (CAT), superoxide dismutase (SOD), and peroxidase (POX) enzymes at ۲۴, ۴۸, ۷۲, and ۱۲۰ hours post-inoculation (hpi) of tomato plants with R. solanacearum and M. javanica. The enzyme activity was measured at each time interval. The CAT and SOD enzymes exhibited maximum activity levels at ۱۲۰ and ۴۸ hpi in the nematode treatment, respectively. Meanwhile, the levels of POX enzyme peaked at ۴۸ and ۷۲ hpi in the nematode and nematode-bacterium treatments, respectively. Pathogen stress eventually led to a decrease in the SOD and POX enzymes ۱۲۰ hours after inoculation and a significant increase in CAT during nematode-bacterium treatment. The results revealed apparent enzyme activity variations in tomato plants infected with both pathogens at different time intervals after inoculation.

کلیدواژه ها:

Bacterial wilt ، Enzyme Activity ، Interaction ، Root-knot nematode