EFFECT OF ESSENTIAL OILS OF SOME MEDICINAL-PLANTS ON PHYTONEMATODES

The essential oils of four medicinal plants belonging to Lamiaceae wer e explored for phytonematode control. The four oils inhibited (P < 0.0 5) nematode motility but Mentha spicata was generally more effective i n reducing the numbers of active nematodes followed by Thymus vulgaris , Majorana hortensis and Mentha longifolia. The main corresponding com pound of each oil, determined by GLC analysis, was carvone (58.14%), P -cymene (40.5%), terpinen-4-ol (41.6%) and carvone (70.36%). Soil stag es of the reniform nematode were more affected by the oil than those o f the ring and lance nematodes. When transferred to water, the total n ematodes that regained their activeness ranged from 12% for T. vulgari s to 60% for M. longifolia. The four 0.1 oil solutions inhibited more than 80% of Meloidogyne incognita-juvenile hatching compared to about 3.5% at the control. The content of oxygenated compounds in these oils ranged from 45.79% to 96.5% and may be partially responsible for the nematicidal effects.