On December 27, 2004 personnel from the General Directorate for Forestry and Soil Management-SEMARNAT (DGGFS-SEMARNAT) detected the presence of powdery mildew, caused by Olivea tectonae, in nursery plants and teak trees (Tectona grandis) of various ages in the municipality of Las Choapas, Veracruz. As a phytosanitary risk mitigation measure, the day after the detection of the fungi, a Benomyl based fungicide at a dose of 120 ml per 100 litres of water in the affected area for these pathogens (20 hectares) was applied. This detection was confirmed by personnel of the Regional International Organization for Agriculture and Animal Health (OIRSA) when they sampled 6 sites to determine the presence and distribution in the above-mentioned municipality during the period of February 14 to March 6, 2005 and in which it was determined that severity ranged from 30 to 90 percent.
The causal agent of powdery mildew was identified by the National Centre for Reference in Forestry Parasitology of the DGGFS-SEMARNAT, with the support of researchers from the Autonomous University of Chapingo and the National Institute for Forestry and Agricultural Research and ratified by researchers and technicians from the Agricultural Research Institute of Panama and the National Centre for Phytosanitary Reference of the Plant Health Directorate -SENASICA-SAGARPA. During sampling activities done by OIRSA personnel on the powdery mildew in the municipality of Las Choapas, Veracruz, the presence of the following hyperparasites fungi was detected: Cladosporium oxysporum and Acremonium recifei.
Presently, in existing teak plantations and nurseries in our country, continuous sampling and diagnosis is taking place, targeted to determine the presence or absence of this pathogen. Also, coordinated actions are being applied to minimize damages caused by this pest, together with DGGFS-SEMARNAT, the National Forestry Commission (CONAFOR), OIRSA, the Plant Health Directorate -SENASICA-SAGARPA and the National Association of Foresters (ANAPLAN).