Effect of bone meal on growth traits, photosynthetic pigment content, and essential oil chemical composition of Pelargonium graveolens

Abstract

Pelargonium graveolens is one of the most cultivated aromatic and medicinal plants in the world and particularly in Morocco, due to its economic importance. The essential oil of this species is widely used in cosmetics and pharmaceuticals. Moreover, the essential oils composition depended on several factors in particular the supply of minerals. In the present investigation, a pot experiment was performed to examine the effect of different rates of bone meal (BM) (0.1%, 0.5%, 1%, 1.5%, 2%, 4%), on the growth traits, photosynthetic pigment content and essential oil chemical composition of P. graveolens. The BM application led to an increase in all growth traits, such as plant height, dry and fresh weights, and photosynthetic pigments content, of which the highest increase in these parameters was found with the 4%BM treatment. In addition, the highest essential oil contents were obtained with the 2%BM (0.28%) and 4%BM (0.30%) treatments. In all treatments, Citronellol, Geraniol, 10-epi-γ-eudesmol, and Citronellyl acetate are major compounds in the essential oils, but their percentages in each treatment were very different. Some compounds such as cis-Rose oxide, geranyl valerate, and Geranyl formate appeared in P. graveolens essential oil when BM was applied at 0.1%, 0.5%, and 1%. While β-Bourbonene appeared in the essential oil when BM was applied at 1.5%, 2%, and 4%.