Hermetic storage systems for maize stored on subsistence farms

Abstract

Abstract: Maize grown by subsistence farmers is a staple food for millions of people around the world, especially in Sub-Saharan Africa and Central America. Following harvest and shelling, maize is subject to storage losses caused by birds, rodents, fungi, and insects. The losses amount to millions of Mg per year of maize, which could be available with no additional inputs of land, seed, fertilizer and water. On-farm hermetic storage has the potential to substantially reduce these losses without the use of pesticides. This paper explains the basis of hermetic storage and presents the Iowa State University procedure for predicting the time required for 100% mortality of adult maize weevils in hermetically-stored maize, shows field data verifying the prediction accuracy, and describes four systems being successfully used for hermetic maize storage on subsistence farms: Postcosecha galvanized steel silos, Purdue triple-bagging system, Grain Pro ultra hermetic bags, Recycled plastic food containers. Based on purchase price, the steel silo is the least cost system. The two bagging systems cost three to four times as much. The recycled oil container is the most costly, in spite of its low purchase price.