ABSTRACT
A common view of microbes is that they are a nuisance – pernicious pathogens that constrain agricultural crop production. This chapter discusses the contributions of fungi with a focus on the fungus Trichoderma, which lives ubiquitously within soil systems. Fungi live ubiquitously within the soil and elsewhere, with some of them living also within plants as symbiotic endophytes. Fungi live also in many other environments aboveground, but they cannot survive where there is no oxygen because, as aerobic organisms, they require oxygen for their metabolism. Trichoderma fungi live and thrive in a wide variety of different ecological niches. Trichoderma strongly interact with other organisms in the soil and elsewhere via their parasitic attacks on other fungi. In the past, such attacks were considered to be the principal mechanism by which Trichoderma could control fungal plant pathogens.
