Shade level effects on yield and chemical composition of the leaf essential oil of Pothomorphe umbellata (L.) Miquel

摘要

Pothomorphe umbellata (L.) Miquel, is a medicinal species that belong to the Piperaceae family and commonly called "pariparoba" and "caapeba". It grows in regions rich in humus, humidity and under the shade of trees, which contribute for its best growth as it is considered a species sciophyte. The effect of shade on the yield and chemical composition of essential oil of Pothomorphe umbellata (Piperaceae) leaves was evaluated. Nine-month-old seedlings were planted in October 2002 and subjected to three shade levels (30%, 50%, 70%) and full sun; the experimental design was in randomized blocks, with four treatments and six replications, in split-plot in time scheme. Two harvests of aerial part were made (05/2003 and 05/2004). Essential oil was extracted by hydrodistillation and chemically analyzed by gas chromatography-mass spectrometry (GC-MS). The highest essential oil yield was observed in the second harvest and plants under 30% shade. Twenty-six chemical substances were identified, of which trans-nerolidol was predominant.