Effectiveness of some clove and citronella oil based-pesticide formulas against root-knot nematode on ginger

Three clove and citronella oil based-pesticide formulas were evaluated their effectivity against root-knot nematode Meloidogyne spp. on ginger in two experimental fields. Three botanical pesticide formulas were mixture formula of: 1) clove and citronella oil, 2) citronella oil and salycilic acid, and 3) clove and java turmeric oil. Chemical carbofuran was used as control chemical pesticide. The experiments were arranged in Randomized Block Design with 3-4 replications (each replication consisted of 10 to 15 plants). Two months after planting, the plants were treated with the formula by drenching the 200 ml of 0.5-2.0% of each formula solution around the plant root system area, then repeated in 14 days interval. At 5-months aged, the plants uprooted, and parameters value were analyzed. Among the three formulas, mixture of citronella oil and salycilic acid at 1.5 and 2.0% concentration effectively reduced the penetration rate of the nematode into roots and rhizome. The formula suppressed the nematode population development in roots as much as 93.75% and the percentage of rhizome-knot symptom as much as 71.60% and 73.17% in two locations consistently. The effectivity of citronella oil and salycilic acid mixture formula towards Meloidogyne sp. could be studied further in ginger plantation.