A very likely consequence of global warming would be a change in the range of some phytopathogens such as Phytophthora capsici, Rhizoctonia solani and Fusarium oxysporum certain micro-organisms to have a distribution limited by temperature. In this study, in vitro we focused on the mean rate of mycelial growth as a function of the time (Vmax = d/t) of the three phytopathogens, at three different temperatures (20, 25 and 30°C) and we also used a series of agrocli-matic indices. The results show that F. oxysporum and R. solani have a very limited distribution at 22 and 30°C (Vmax ≈ 10 mm) for 72h; however P. capsici showed a Vmax ≈ 20 mm for 72h the pathogenicity testing made by artificial inoculation of pepper seedlings shows that P. capsici is very aggressive at 30°C, F. oxysporum showed virulence only at 25°C but R. solani lost all virulence between 22 and 30°C.