Mycoflora of grain maize (Zea mays L.) stored in traditional storage containers (gombisa and sacks) in selected woredas of Jimma zone, Ethiopia

Abstract

Mycoflora of maize (Zea mays L.) grain (Variety: Bako Hybrid-660) stored in two traditional storage containers (Gombisa and Sacks) for 180 days was studied for mycoflora in two agro-ecologies, that is Intermediate and Lowland, with altitude ranges of 1500-2500 meters above sea level, and 1000-1500 meters above sea level, respectively, in Jimma zone, Ethiopia. The temperature and relative humidity were observed for identifying fungi species which can flourish and cause maximum deterioration to maize grains. Significant (P<0.05) decreases in germination rate of the grains were observed with time under each storage method for both the low and intermediate altitude ranges. Germination percentage reduced from 98% and 97.5% to 68.5% and 80.5% for grains stored in Gombisa and Sacks, respectively. Storage type significantly (p<0.05) affected seed germination under intermediate agro-ecology whereas no significant (p>0.05) effect was observed under lowland agro-ecology due to storage container type. One sterile white mycelium and a total number of eight species of fungi viz., Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, Aspergillus tereus, Cladosporium cladosporioides, Drechslera halodes, Fusarium oxysporum and Penicillium chrysogenum were identified from maize grain at the beginning and during storage. The most common fungi recorded from both agroecologies in the two storage structures were A. flavus, A. niger, D. halodes and F.oxysporum. These fungi were recorded from 90, 51, 72 and 44 percentage of the seed samples, respectively. In the districts of both intermediate and lowland agro-ecology these fungi were consistently recorded throughout 180 days, during storage. A. fumigatus was detected in3.6% of samples while C. cladosporioides observed in 15% of the samples. Fungal species A. tereus and Penicillium were recorded in 0.5% of samples in selected districts of Jimma. These fungal species were known to cause deterioration of maize and are a health risk to humans and animals due to the toxins they potentially produce.