Worldwide traditional agricultural practices are increasingly being affected by various problems such as diseases, pests, droughts, decreased soil fertility due to use of hazardous chemical pesticides, pollution and global warming. There is thus a need for some eco-friendly biocontrol agents that may help to resolve some of these problems. Biological
control, the use of specific microorganisms that interfere with plant pathogens and pests, is a nature-friendly, ecological approach to overcome the problems caused by standard chemical methods of plant protection (Harman et al. 2004). Bacteria and fungi are involved in biocontrol activity, and the fungal genus Trichoderma plays a major role in controlling the plant diseases. Trichoderma spp. are free living fungi that are highly interactive in root, soil and foliar environments.