Assessment of Storage Losses of Maize in Three Districts of Bhutan

Karma Dorji, Dechen Tshering, Sonam Lhamo


Storage loss of maize (Zea mays) in Bhutan is assumed to be high but there is insufficient data to validate it. This study was conducted in the three major maize growing districts of Bhutan covering nine locations to assess and determine the storage losses of maize in traditional method of storage in the attic floors and hanging method.  The total grain loss was estimated as the sum of the percentage of grains damaged by insects and fungal diseases counted from two different storage methods and at different storage months which is estimated to be six months of storage period. At the end of six months storage, the total mean storage losses were 16.18%, 38.21% and 23.83% for Chukha, Dagana and Mongar, respectively. The damage from insect during storage was recorded at 9.11%, 36.41% and 9.81% during December while in March it increased to 14.91%, 21.99% and 15.7% for Chukha, Dagana and Mongar, respectively. Similarly, fungal damage increased from 0.95%, 8.10% and 6.50% in December to 1.27%, 16.22% and 8.03% in March for Chukha, Dagana and Mongar. There was no significant difference in losses from insect, fungal damages and total storage losses between the two storage methods. Storage losses of maize grains from insect infestation were higher compared to fungal diseases in all the study locations. Storage losses were slightly higher in the low altitude locations in all the three districts. The survey findings indicated that there is a major loss of maize during the storage with maximum losses caused by insect damage followed by fungal infection. This study recommends the design and promotion of improved storage methods and interventions in good post-harvest management to minimize losses during the storage.

Keywords: Maize, Storage loss, Insect, Fungal

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