– Pierce A. Paul, Department of Plant Pathology, Ohio State University Extension
Accurate testing depends on thorough and appropriate sampling and sample processing.
Moldy grain and vomitoxin levels vary considerably within the grain lot. This is largely because the number of ears infected with Gibberella zeae, the fungus that causes Gibberella ear rot and produces vomitoxin in the grain, and number of infected kernels on a given ear within a field are highly variable. In addition, ears, and kernels with a similar appearance in terms of surface moldiness may have vastly different levels of internal fungal colonization, and consequently, different levels of vomitoxin contamination. In addition, pockets of warm, humid area in the grain lot coupled with moldy grain may lead to vomitoxin “hot spots” that can affect vomitoxin test results if sampling is inadequate. This may lead to price discounts or rejection of grain lots that are less contaminated than test results suggest, or conversely, acceptance of lots that are more contaminated than indicated by the results. For instance, if a single sample is drawn and the location from which it is drawn happens to be a hot-spot, then the overall level of contamination of the lot will be overestimated. Conversely, if the sample misses the hot spots completely, vomitoxin contamination may be . . .
Continue reading Sampling Corn Grain for Vomitoxin