Investigating Disease Control Options for Potatoes in Storage
The quality and volume of potatoes can be substantially lowered in a relatively short amount of time if proper storage practices are not employed. Nearly 82% of the potatoes produced in Idaho are stored for some duration. In most years, a loss in storage due to shrink and disease is approximately 6 to 7% but can be higher if frost or wet rots have affected the crop. Minimizing potential storage loss is always a major concern for storage managers. Stakeholder and other industry inputs have indicated disease control needs for processing, fresh market and seed potatoes as an area of research emphasis. It is important to minimize wounding of the crop during harvest and handling to reduce susceptibility to many storage diseases. The impact of wounding and predisposition to disease development can also be influenced by cultivar, pulp temperatures and
storage conditions. Post-harvest applications of either sprout- or disease-control agents to tubers are often made to help maintain quality prior to entering the storage facility and after leaving the packing shed. There are very limited data on the impacts from the use of post-harvest disease-control agents on wound healing. The use of phosphorous acids as a low-pressure spray application on potatoes being loaded into the storage facility is gaining nationwide acceptance. This product is very effective in minimizing the spread of pink rot and late blight in storage. There is currently no data on the impact of wound healing in storage after applications of this product. Additional products being used in the industry include disinfestants applied on either potatoes going into storage or just prior to being packaged and shipped. Additionally, for both the organic and conventional markets,
microbial biocontrol agents are also being considered. Again, there is limited information on these post-harvest products on the potential effects on wound healing, efficacy and subsequent tuber quality. Data on this response would be beneficial to fully recognize the use and impacts of these post-harvest disease-control agents. The potato industry has gained a few novel post-harvest products in the last several years although there is still a paucity of post-harvest chemicals and/or application methodologies available to the industry. The lack of effective products to control disease in storage prompted the industry to support and evaluate the use of additional control agents in storage. Products with low food safety concern need to be tested as viable post-harvest disease-control agents. Research information will help establish recommendations on the use of post-harvest disease-control
products and if additional alternative products or methods need to be identified. Various methods of applications, such as application via aerosol or humidification, may need to be implemented in some situations to elevate efficacy. The impact of this project will be to provide research based information to the potato industry regarding storage management of diseases and the use of post-harvest disease control products.