Rational Management of Botrytis-Incited Diseases: Integration of Control Measures and Use of Warning Systems

Botrytis-incited diseases are currently managed by routine application of fungicides. This strategy has become increasingly unacceptable and alternative approaches for rational disease suppression are urgently needed. This goal can be achieved either by applying fungicides only when needed, thus eliminating unnecessary sprays, or by integrating chemical and non-chemical measures so that the nonchemical measures compensate for the reduction in fungicide use. In this chapter, the methodology for rational management of Botrytis-incited diseases is presented, and case studies are described. The decision to omit unnecessary fungicide sprays may be guided by warning systems, several of which have been developed for Botrytis management over the years. All systems attempted to recognize conditions highly conducive to spore germination and host penetration, and to schedule fungicide applications accordingly. The use of biocontrol and implementation of cultural practices as stand-alone measures for Botrytis management are not always sufficient, but integration of these measures with chemical control has proved effective. In most cases experimental use of these approaches enabled a significant reduction in fungicide use without increasing the risks of uncontrolled Botrytis outbreaks. It was concluded that rational management of Botrytis-incited disease is feasible, and that within a few years, Botrytis will be primarily managed by non-chemical measures supported by a few properly timed fungicide applications.