Abstract

Gmelina arborea Roxb is a fast-growing forest species adapted to the edaphoclimatic conditions of Ecuador, a quality that has stimulated the establishment of intensive plantations for commercial purposes. A disease with characteristics of vascular wilt and stem rot is killing thousands of trees in the country. Ceratocystis fimbriata is listed as the causative agent of the disease, However, the complex symptoms and the frequent isolation of Fusarium spp. from diseased trees, make us suspect that this phytopathogen is involved in the pathogenesis of melina. Koch's Postulates were applied at the greenhouse level, and for the effect, 5 treatments based on the inoculation of 17 plants G. arborea of 4-month-old per treatment were plated. T1 = Fusarium sp.1, T2 = Fusarium sp.2, T3 = Fusarium sp.3, T4 = Fusarium sp.4, and T5 = agar-agar (control). A complete randomized design (DCA) was used and the plants were evaluated 155 days after inoculation. The treatments Fusarium sp.1 and Fusarium sp.2 caused the largest apparent volumes of necrosis (2.31 cm3 and 2.43 cm3 ), and generated mild symptoms of disease, however they did not die. These results are considered as a baseline, and would indicate the involvement of Fusarium spp. in melina disease, but they are not conclusive