The jaborandi (Pilocarpus microphyllus Starf.) is a medical plant found in Maranhão State, Brazil, which is the natural source of the drug pilocarpine used to treat glaucoma, a disease that frequently causes blindness. The leaves used for extraction of pilocarpine are presently collected from plants that grow naturally. Instead of pure extractive exploitation it has been tried the cultivation of this plant in order to improve and increase the production. Nevertheless, 90% of 160,000 young seedlings were lost due to the infestation of Meloidogyne incognita race 1. Research showed the soil as the source of infestation.