ABSTRACT
This chapter focuses on the role of chemical pesticides in altering the efficacy of plant pathogens, mostly fungi applied as biological control agents. Many experimental and practical examples exist that demonstrate that chemical pesticides and biocontrol agents can be successfully integrated to obtain increased weed control efficacy, improved spectrum of weed control, reduction in herbicide rates needed for weed control, or improved systems of integrated pest management. It is well established that herbicide use is frequently associated with increased fungal incidence and disease severity in certain cases in treated crops. Trifluralin, a preemergence herbicide against many annual grasses and broadleaf weeds, affects seed germination and growth processes. From the foregoing examples several possibilities for exploitation of nontarget pesticide effects to aid bioherbicide efficacy come to mind. To be practical and to achieve selectivity in application without injuring the crop species, special techniques such as slow release formulations, herbicide safeners, and timing of applications may be necessary.
