Allelopathic effects of aromatic species intercropped with coffee: Investigation of their growth stimulation capacity and potential of caffeine uptake in Puebla, Mexico

In this study, the potential uptake of caffeine by spearmint (Mentha piperita L.), basil (Ocimum basilicum L.), sage (Salvia officinalis L.), and oregano (Origanum vulgare L.) and conversely, the allelopathic effects of these herbs on physiological parameters in coffee (Coffea arabica L.) were investigated. Two ecological conditions in rural area of Puebla State, Mexico (2004–2005), as well as laboratory bioassays were evaluated. To summarize the results: (i). Intercropping sage, spearmint, basil and oregano stimulated the plagiotropic growth of Coffea arabica plants. (ii). Volatiles from essential oils induced stomata opening in coffee leaves. (iii). Aromatic species, principally sage and oregano absorbed caffeine and may contribute to reductions of the caffeine contamination of the soil. (iv). Finally, coffee growers can get extra income by intercropping aromatic plants during the no-harvest period (April – November) in between coffee rows of young production systems.