EFFECT OF VARYING COMBINE HARVESTER CONFIGURATIONS ON FUSARIUM DAMAGED KERNELS (FDK) AND DEOXYNIVALENOL ACCUMULATION IN WHEAT GRAIN HARVESTED FROM PLOTS WITH DIFFERENT LEVELS OF FUSARIUM HEAD BLIGHT

摘要

To evaluate the influence of varying combine harvester configurations on Fusarium damaged kernels (FDK) and DON in wheat grain harvested from plots with different levels of FHB.Fusarium Head Blight (FHB), caused predominantly by Fusarium graminearum Schwabe (te-leomorph: Gibberella zeae) in North America, is a serious disease of wheat (Triticum aestivum L.) and other small grain in all wheat-growing regions. Infection of wheatspikes may cause significant grain yield and quality losses due to poor grain fill, high percentage of damaged (scabby) kernels, and low test weights. In addition, infected grain accumulates deoxynivalenol (DON), a mycotoxin produced by this pathogen (Bai and Shaner, 1994, and McMullen et al, 1997). DON, also known as vomitoxin, represents a health threat to humans and livestock, therefore mycotoxin-contaminated grain is either rejected or priced down in commerce. Research has shown that DON levels arepositively correlated to Fusarium damaged kernel (FDK) and other visual estimates of FHB (Paul et al, 2005). As such, reducing FDK generally leads to reduction in DON. Integration of resistant cultivars, fungicide applications and agronomic practices arecommonly recommended to reduce FDK and DON in harvested grain (McMullen, 2007). Management recommendations also include strategies to eliminate scabby, light-weight kernels during harvest by adjusting combine settings. However,