Abstract

ALMARAZ-SANCHEZ, Alejandra; ALVARADO-ROSALES, Dionicio  and  SAAVEDRA-ROMERO, Luz de L.. Trapping of Phytophthora cinnamomi in oak forests with two ornamental species and induction of sporulation. Rev. Chapingo ser. cienc. for. ambient [online]. 2013, vol.19, n.1, pp.5-12. ISSN 2007-4018.  https://doi.org/10.5154/r.rchscfa.2011.09.062.

Oak mortality has increased in recent years in several Mexican states. The etiology in many cases is unknown. In the states of Colima, Jalisco and Guerrero, where the cause is known, the oak forests are being affected by the "ink disease" (Phytophthora cinnamomi Rand). The presenting symptoms of diseased trees are: chlorosis, necrosis, wilting, cankers with dark exudates on the bark of the trunk and dieback. Given the impact of the disease and the difficulty of isolating the pathogen from cortical tissue and inducing sporulation in it, this study aimed to (i) evaluate the efficiency of two trap plants, Camellia japonica and Rhododendron indicum (L). Sweet, using a soil suspension and (ii) induce sporulation of the pathogen. To this end, 6 mm discs containing leaf tissue of the trap species were embedded in a soil suspension for 24 and 48 h before being plated in PARPH selective medium. The species R. indicum showed higher capture effectiveness, 64.10 %, compared with 6.83 % for C. japonica. For sporulation, a water-soil mixture (350 mL-200 g) gave the best results.

Keywords : Soil; oak; camellia; azalea; sporangia.