Global change and plant diseases.

The importance of the environment on the development of plant diseaseshas been known for centuries (Colhoun, 1973). It is known that the environment can influence the growth and susceptibility of the host plant, the reproduction, dispersal, survival, and activities of the pathogen, as well as the interaction between the host plant and the pathogen. For this reason, global change represents a serious threat to agriculture, because they can promote significant alterations in the occurrence and severity of plant diseases. Such alterations may represent serious economic, social, and environmental consequences. Analyzing these effects is essential for the adoption of mitigating measures, in order to avoid future damages (Ghini, 2005). In the past, several epidemics that occurred in Brazilian agriculture could have been avoided or have their damages reduced if studies would have been carried out for the adoption of preventive measures