Effects of Marigold Extracts for Controlling Root-knot Nematodes of Tomato

Abstract

Effects of the extracts from three marigold varieties, i.e. King Yellow, Galore, and French for controlling root-knot nematode (Meloidogyne spp.) of tomato (Lycopersicon esculentum) grown in the greenhouse were investigated. Extracts from whole plant, stem and leaf, and root of those varieties were used in the experiment. The extracts were dispensed twice to 30 days old tomato stem base in pots every 2 weeks. Records were done in 1 and 2 months after treatments. The results showed that after 1 month, all extracts not reduced the gall number. However after 2 months trials, Kings Yellow extracts showed the best results, especially the extract from the root, gall number percentage increased to 5.31 while the inoculated control reached to 300.30%. Moreover, the effects of the extracts on the growth of tomato were also investigated. The result showed that all extracts were promoted the height and fresh weight of treated tomato plants. When comparing among the extracts from each part of each varieties, plant fresh weight but not height promotion effects were considered to be difference.