Assessment of inoculation methods to identify resistance to Fusarium crown rot in wheat

Crown rot, caused by Fusarium culmorum and Fusarium pseudograminearum, is one of the most pervasive diseases of wheat throughout the world. Fusarium culmorum is the most prevalent causal agent in Turkey while F. pseudograminearum is the most predominant in the USA. Consistent and reliable screening methods are required to accelerate the identification and development of wheat cultivars for resistance to Fusarium crown rot in breeding programs. A multifactor experiment with seven replicates was established investigating three different inoculation techniques (seedling dip, stem base droplet and colonized grain) using two pathogenic isolates of F. culmorum in Turkey and Fusarium pseudograminearum in the USA, respectively, against known moderately resistant and susceptible wheat cultivars under controlled greenhouse conditions. Plants were harvested and evaluated for crown rot severity using a 0-10 rating scale. Results indicated that disease severity was greater in seedling dip, compared to colonized grain, and stem base inoculation (in decreasing order of severity), respectively. However, the colonized grain method produced an adequate level of severity and consistent cultivar ranking in both experiments. Results showed significant cultivar 9 inoculation method interactions, and the two species of Fusarium were considered to be virulent.