Occurrence and Leave Extractable Essential Oil of Lippia multiflora M. (Verbenaceae) as Affected by Soil Acidity, Carbon, Nitrogen and Phosphorus Contents in North Cote d’Ivoire

Abstract

For generating a strategy of quantitative and qualitative productions of invasive Lippia multiflora, influence of soil pH and the contents of organic carbon (C), total nitrogen (Nt), total (Pt) and available (Pa) phosphorus were explored via dominant-abundance (DAI) and aggregation (AI) index of the species as well as the leave extractable essential oil. In three sites (Labelekaha, Taoura and Zievogo) of L. multiflora ecosystem in north Cote d'Ivoire (Sudan savanna), corresponding DAI and AI were recorded coupled with soil and leave sampling at different topographic sections. Soil pH and the contents of C, Nt, Pt and Pa were determined as well as the concentrations of essential oils. Occurrence of L. multiflora was highest in the down slope position of the landscapes with significant influence of Pa also noticed for essential oils mainly characterized by highest concentrations of Geranial, Neral, α-Phellandrene, Para-Cymene, Limonene+β-Phellandrene and α-Humulene. The effect of soil organic C, and Nt were accounting for hydromorphic condition as occurred at Ziévogo. The cultivation of L. multiflora may be possible in down slope position applying P for high yields of leaves and essential oils mainly composed of terpenoid derivatives. Further applications of organic C and N are required for hydromorphic soil.