Effect of Hermetic Storage Bags and Storage Duration on Occurrence of Storage Insect Pests in Seeds of Cereals and Legumes

Abstract

Hermetic storage has been introduced and disseminated in some parts of Ethiopia; although their efficacy in protecting  seeds has not been studied. Thus, a study was conducted to determine whether different hermetic storage protect or  not tef, durum wheat, lentil, and chickpea seeds from damage by storage insect pests over various storage periods. The  hermetic storage tested were GrainPro super bag, Purdue Improved Crop Storage (PICS) bag, and fertilizer bag, while  polypropylene bag was used as control. In each bag 10 kg of insecticide untreated seeds of tef, durum wheat and  chickpea and 4 kg of lentil seed was put and stored for 6, 12, 18 and 24 months. The treatments were arranged in two  factor nested design and treatments were replicated three times. Only lentil and chickpea seeds were infested by Adzuki  bean beetle (Callosobruchus chinensis). It was found that throughout the tested storage periods, lentil seeds  stored in PICS bag and GrainPro super bag had the lowest proportion of seeds with egg or hole; the lowest average  number of eggs per seed; and holes per seed than seeds stored either in polypropylene bag or fertilizer bag. Relatively  high level of infestation was found on chickpea seeds stored in a single inner layer GrainPro super bag and  polypropylene bag. There were no insect infestations in both tef and durum wheat seeds stored in all packaging  materials. Therefore, PICS and GrainPro super bags (as double layer) are effective in protecting both cereals and pulses  from insect pests in storage.