Control of Pathogen Erysiphe alphitoides Present in Forest Crops in Current Climatic Conditions

Abstract

The production of oak seedlings in intensive crops involves the modification of natural conditions, namely the degree of humidity, through artificial irrigation, which favors the appearance of the pathogen Erysiphe alphitoides, responsible for the Oak Powdery Mildew (OPM) disease. Thus, it is necessary to identify new substances and technologies to control OPM. In this sense, new products approved by the European Union (EU) and Forest Stewardship Council (FSC) were identified, both synthetic and, a great novelty, biological (based on chito-oligosaccharides-oligogalacturonans: COS-OGA). In order to quantify the results, a correlation was made with climatic factors, by sampling data related to temperature and relative humidity with Data Logger devices. The obtained results suggest that OPM has a high virulence in the temperature range of 20 to 30 °C; at a relative humidity above 75%. The data obtained from the field experiments show that the synthetic products controlled OPM with an effectiveness between 70% and 95%, and the biological product behaved almost similarly, between 60% and 90%, which creates high opportunities for environmentally friendly control of forest pathogens.