Hermetic on-farm storage for maize weevil control in East Africa

Maize (Zea mays L.) consumption makes up over half of daily caloric intake of persons in East Africa and adequate supply is necessary for food security for subsistence farmers, as well as for domestic stability. Hermetic post-harvest maize storage is an attractive non-chemical control strategy for maize weevil,Sitophilus zeamais (Motsch.), which is the principal cause of insect damage to stored maize grain. Laboratory experiments were conducted on instrumented hermetic and non-hermetic containers to measure effects of temperature (10 vs. 27°C) and maize moistures (6.3 to 16%) on maize weevil biology and mortality rate, and to quantify weevil oxygen consumption. Ten days weevil mortality was significantly higher in hermetic vs. non-hermetic storage, in 6.3% moisture maize vs. 16%, and at 27°C storage temperature vs. 10°C. Oxygen depletion results allow estimation of days to 100% adult weevil mortality as a function of weevil infestation level, storage temperature and maize moisture for East Africa conditions