Assessment of association of storage practices, fungal pathogen and nutritional quality of stored maize (Zea, mays L.) At farmers’, collectors’ and wholesalers’stages in jimma zone, Ethiopia

Abstract

Maize(Zea mays L.)is a major staple food source for millions of people in Ethiopia. Due to its high productivity and low cost of calorie it is preferred crop for food security of the country. Likewise, in Jimma zone maize ranked first both in production and productivity compared to all cereals and a major staple food crop for large number of households. Even though, the crop plays a key role in household food security the benefit of higher production and productivity has been negated due to high post-harvest loss. Thus, this study was conducted to assess association of storage practices, fungal pathogens and nutritional quality of store maize at farmers’, collectors’ and wholesalers’ storages condition in selected districts of Jimma Zone. The study was conducted in five purposively selected districts (Dedo Kersa, Omo Nada, Mana and Sokoru) which represents the three agro-ecologies of Jimma zonefrom January 2014 to June 2015. Multi-stage sampling procedure was used to select the target groups. Totally 342 respondents were interviewed using semi-structured questioner. For laboratory experiments farmers who produce HB-660 variety and store their maize in “gombissa” were purposively selected. Morphological identification of fungal pathogens wascarried out by direct plating method monthly interval. However, nutritional analysis was done every two month interval starting from harvest to six month storage following AOAC methods. Both qualitative and quantitative data were analyzed using SPSS version 20 and SAS version 9.0. Survey result showed, about 12 post-harvest activities were practiced by farmers and some of the activities also used by traders. Three maize storage structures (gombisa, modified and bag) were identified. However, most of the farmers(>75%) use gombisa which is constructed from bamboo or Soyam wood. Comparing different activities alongpost-harvest period, storage loss identified the critical loss point based on producer’s perception. In totalseven fungal genera were isolated. However, Fusarium, Pencillium and Aspergillus spp.were predominantly identified in all samples with decreasing order.Mould incidence and severity in stored maize showed significant (P <0.05) difference both for storage duration and agro-ecologies for different actors. Nutritional analysis result showed significant (P< 0.05) effect of storage duration and agro-ecologieswere observed on moisture contentof stored maize under all actors storage condition.Crude protein, fat carbohydrate and caloric value were significantly (P<0.05) decreased as the storage duration increased.But, fiber, ash and mineral (Ca, Zn and Fe) content were slightly increased along the storage period whereas, phosphorus content declined along the storage period. The carbohydrate and calorific value were significantly declined from 68.1±0.6% and 349.5±3.4 Kcal to 60.6±0.6% and 305.03.4 Kcal after six monthsof storage. This finding showed that fungal load increased and nutritional quality declined as the storage duration increased. Moreover, the most important mycotoxins producing fungi are dominantly found infecting maize along the value chain. Furthermore, different actors along the value chain are less awared about health hazard of those pathogens. This research highlights, the need for determination of mycotoxin associated with those fungi genera. There is also need for awareness creation all stakeholders on postharvest loss reduction and also health impact of mouldy maize.