Abstract
Tolima is one of the largest zones in Colombia where avocado and rice are produced. The disease management programs for these crops are mainly chemical-dependent and tend to have variable results since the diagnosis of some diseases is based on unspecific symptoms. In this context, the present study aims to bring information about the phytopathogens affecting Tolima´s rice and avocado crops. From foliar tissue, culm, and roots of rice plants, 18 isolates closely related to Gaeumannomyces graminis var. graminis/G. oryzae and 06 Magnaporthe oryzae were obtained. The isolation of these fungi was concordant with the crown sheath rot and rice blast symptoms observed. Also, 13 different fungi belonging to the C. acutatum and C. gloeosporioides complex were isolated from avocado fruits with symptoms of anthracnose. Interestingly, only two Phytophthora sp. isolates were purified from necrotic roots of avocado trees. However, several fungi belonging to the Cylindrocarpon/Ilyonectria genera and one strain identified as Bjerkandera adusta were isolated from these samples. Symptoms caused by these fungi are similar making it necessary to do a differential diagnosis of the actual pathogen causing avocado root necrosis. The data obtained constitute the first report of the above-mentioned phytopathogens in Tolima avocado crops and established the basis for an epidemiologic study of its distribution in Colombia.
Key words: Rice, avocado, Gaeumannomyces, Magnaporthe, Phytophthora, Cylindrocarpon, Ilyonectria, Colletotrichum