Effect of temperature and pH on the growth of Fusarium spp. causing Fusarium head blight (FHB) in wheat

Abstract

Fusarium head blight (FHB) or head scab is emerging as a destructive disease affecting the quantity and quality of wheat worldwide. Several Fusarium spe-cies have been associated with the disease but their composition varies among geographical regions and years. Climatic factors like temperature, pH and humidity influence the growth, survival and infestation of Fusarium species. In the present study, response of thirty six isolates of three Fusarium spp. viz F. graminearum, F. oxysporum and F. pallidoroseum (F. semitectum) to different temperature and pH was assessed by analysing their in vitro growth rate (mm/day) on potato dextrose agar (PDA) medium. We found that all the isolates responded differentially but interestingly isolates of F. graminearum showed better tolerance at broader range of temperature and pH. This attributes make F. graminearum a widely distributed and potent pathogen of wheat.