ASSESSING THE COMPARATIVE PERFORMANCE OF PAINTED AND NON PAINTED METALLIC GRAIN STORAGE FACILITIES ON MAIZE GRAIN

Abstract

Lack of effective storage facilities to mitigate post harvest losses threatens the profitability of harvested maize grains. In Malawi, small scale farmers use traditional cribs, gunny bags and pesticides which just aggravate the losses. Currently small metallic grain storage facilities, which have proven to be effective, have been introduced. The effect of these small metallic grain storage facilities on maize grain in the tropics has little been studied and documented. This study set out to investigate the effect of painting on the temperature and quality of maize in small grain metallic silos. Specifically the study set to investigate the effect of painting on the storage temperatures in small grain metallic silos; to investigate the level losses of grain stored in painted and non-painted metallic silos. An experiment was conducted to assess the comparative performance of painted and non painted metallic grain storage facilities on maize grain under a typical tropical weather condition in Zomba, Malawi. Four small grain metallic silos of 250 kg capacity were installed. Two were painted white, and the other not painted. Each silo was filled with 250 kg of MH 18 maize variety (Zea Mays) at 11.5 % moisture content (wet basis), obtained from Makoka Research Station. The cleaned, weighed and sound maize grains were stored in the silos, which were then tightly closed and placed under a shed. Temperature variations within and outside the silos were monitored for 120 days during storage.v Results on temperature variation, moulding and caking between painted and non-painted metallic silos have been documented. Higher temperatures have been constantly observed in non-painted silos. This was true in all silo locations. These results were consistent when using graphs, t-test or ANOVA. Caking and moulding was also more pronounced in non-painted silos than painted ones. To a greater extent, this was more adverse on the silo walls. The results of this study provide satisfactory evidence that painting had a considerable effect in controlling inside silo temperatures and also helped to maintain the quality of the stored grain. This clearly shows that painting can greatly improve the performance of the metallic silo and bring gains in the quality of the stored grain. In this regard, white painting of small metallic grain silos would be highly recommended to all stakeholders, particularly, small scale farmers in similar tropical conditions.