Evaluation of Marigold (Tagetes Erecta L.) Flower Essential Oil for Antifeedant Activity against Spodoptera litura F.

Marigold essential oil was obtained through hydrodistillation ffom the fresh flower petals collected from the experimental field of Indian Agricultural Research Institute, New Delhi. The oil yield was 0.1%. The dried oil was injected to a GC-MS, which yielded ten peaks. The mass spectra of five out of the ten compounds could be analyzed. The spectral fragmentation pattern revealed that the volatile constituents of marigold oil are mixture heterogeneous components. The first three compounds were identified as α-sesquiphellandrane (I), β-sesquiphellandrene (II), and 2-methyl-6-(4-methyl cyclo hexadienyl) hept -4-en-2-ol (III), respectively. The remaining two compounds were tentatively assigned the structure as myristoleic acid (IV) and trieicosane (V), respectively. The essential oil extracted through hydrodistillation showed fairly good antifeedant activity (EC₅₀ 680 μg mL⁻¹) against Spodoptera litura larvae.