Detecting storage pathogens by monitoring volatiles in the storage atmosphere

Authors: Bethke, Paul

Submitted to: Potato Association of America Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 3/28/2012
Publication Date: 8/13/2012
Citation: Bethke, P.C. 2012. Detecting storage pathogens by monitoring volatiles in the storage atmosphere [citation]. Potato Association of America Proceedings. Paper No. 011.

Interpretive Summary:

Technical Abstract: Pathogenic rot of stored potatoes results in loss of product and decreased tuber quality on an annual basis. The objective of this research project is to determine if measuring the abundance of low molecular weight volatile compounds in the atmosphere of bulk potato storages provides information that can be used to detect or monitor the activity of bacterial or fungal pathogens that cause spoilage of the crop. Air samples were removed from the return air in research storage bins and from commerical potato storages. Compounds were identified and quantified using gas chromatography. Sixteen compounds were monitored including 8 that have been found previously to be associated with fungal or bacterial infection of tubers: acetaldehyde, acetone, 1-butanol, ethanol, ethylene, MEK, 1-propanol and 2-propanol. Each was identified in multiple samples from commercial and research storages. Potato storages with low amounts of volatile compounds typically had few problems with rot. Potato storages that had ongoing, extensive problems with pathogenic rot, on the other hand, typically had higher amounts of volatile compounds. Ethylene, 1-propanol and acetone appear to be useful markers for pathogen activity. Other unidentified compounds also increased in abundance when pathogen activity increased. These data suggest that volatile monitoring might be a useful tool for potato storage management. Early season measurements could indicate how likely it is that pathogen activity will limit storage duration. Alternatively, an increase in the volatiles being produced might indicate that pathogen activity has increased and greater vigilance or an active response is required. The data indicate that both kinds of information may be available.