Submitted to: National Fusarium Head Blight Forum Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 11/1/2004
Publication Date: 12/11/2004
Citation: Zhang, X., Jin, Yue. 2004. Investigation of kernel infection by Fusarium graminearum in wheat. Proceedings of the 2nd International Symposium on Fusarium Head Blight. December 11-15, 2004. Orlando, Florida
Technical Abstract: Fusarium head blight (FHB) or scab of wheat is a destructive disease. Screening for FHB resistance of wheat relies heavily on field nurseries. Besides assessment of visual symptoms on the spikes, estimates of kernel damage by the pathogen on the basis of percentage of Fusarium-damaged kernels (FDK) or visual scabby kernels (VSK) and concentration of deoxynivalenol (DON) have been a common practice in measuring the disease. Variations of kernel color and size pose difficulties in distinguishing Fusarium damage from environment-induced damage and in interpreting data. This study was to investigate infection by F. graminearum of seed harvested from field FHB nursery, to compare seed infection with VSK, DON, and seed infection levels with the visual appearance of the kernel measured by kernel color and size. The fungus was recovered from all classes of wheat kernels with the highest infection occurring in the class of shriveled and discolored kernels. Seed infection and VSK was highly correlated whereas seed infection and DON concentration was not correlated. Results also indicate that environmental stresses in a field nursery, i.e. excessive moisture and high temperature, can induce discolored and shriveled kernels, thus confounding the effects of seed infection by the pathogen.