However, over the past 35-40 years, there has been increasing use of these pathogens, in both the classical and inundative approaches. Among pathogens, fungi re usually preferred over bacterial or viral agents in classical control programmes (Char udattan, 2001), mainly because they generally do not require a vector for dissemination but also because they often have higher specificity. Although root pathogens cause some of the most devastating plant diseases, leaf pathogens have been preferentially selected as biocontrol agents, as they are usually more specific and more easily dispersed by wind or rain (Watson, 1991).