Etiology of premature plant death in coriander (coriandrum sativum L.) in ocotlán de Morelos, Oaxaca, Mexico and effect of essential oils in vitro on the pathogen [Etiología de la muerte prematura del cilantro (coriandrum sativum L.) en ocotlán de Morelos, Oaxaca, México y efecto de aceites esenciales in vitro sobre el patógeno]

The etiology of premature death of the coriander (Coriandrum sativum L.) plant in Oaxaca, Mexico was determined and the effect essential oils of Syzygium aromaticum, Thymus vulgaris, Origanum vulgare, Cymbopogon citratus, Bursera linanoe, Laurus nobilis, Larrea tridentata and Mentha pulegium was assessed, in dosages of 50, 100, 200 and 400?l.l-1 of potato-dextrose agar culture medium, on the inhibition (%) of in vitro mycelial growth of the pathogen. Fungal isolates were obtained from the roots of symptomatic coriander plants and their pathogenicity was verified in non-symptomatic coriander plants. Morphometric and molecular characterization of the pathogen was done and was identified as Fusarium oxysporum. The fungi caused constriction of the primary roots, rot of secondary roots, wilt and premature death of 100% of inoculated plants after 20 days. S. aromaticum and T. vulgaris oils in 100 and 200?l.l-1 dosages, respectively, inhibited 100% of F. oxysporum mycelial growth. O. vulgare oils at a dose of 400?l.l-1 showed 96% growth inhibition. For the other oils, 400?l.l-1 doses inhibited between 12 and 46% of fungal growth.