Efficiency of different storage facilities in reduction of insect pest in sun-dried sardines (dagaa) from Lake Victoria

Abstract

The study was conducted to assess the efficiency of different dagaa storage facilities used in local markets. Experiment for infestation rate was conducted in Pest Management Centre at Sokoine University of Agriculture (SUA) using four facilities namely; hessian sacks, woven sacks, used boxes and polyethylene bags for eight weeks. Dagaa (dried sardines) samples were collected from Central market in Morogoro municipality Identification and counting of insect pests was conducted under dissecting microscopes. Two major groups of insect pest were identified namely; mites and beetle both at adult and larvae stage. Two species of beetles; namely Necrobia rufipes and Dermestes sp. were identified and recorded. Significant differences were noted in terms of abundance with mites forming more than 90%. Similarly significant differences in abundance of insect pest among the storage facilities (P<0.05) were noted. The highest abundance of beetle larvae (8.1±1.7 no/kg) and adults (1.18±0.7 no/kg) were recorded from hessian sacks. The highest and lowest abundance of mites were recorded from hessian sacks (3105.5±245 no/kg) and polyethylene bag (266.3±34.2 no/kg) respectively. Abundance of beetle larvae varied with time in all facilities except polyethylene reaching peak during the fourth week and declining gradually after the fifth week. No clear pattern was observed for the infestation rate of the adult beetle. Rapid increases in density of mites during the fifth week in hessian sacks, woven sacks, used boxes facilities and in polyethylene bag during the seventh week were noted. The higher abundance and infestation rate of insect pest recorded from hessian sacks followed by woven sacks and used boxes. There was higher number of mites compared to beetles. It can be concluded from this study that polyethylene bags are more efficient in controlling insect pests for dagaa and provide longer shelf life compared to other facilities. Therefore, it is recommended that for lower infestation rate and increased shelf life for dagaa, processors, whole-sellers and retailers should pack their products in polyethylene bags immediately after drying.

Keywords: Dagaa, storage facilities, insect pests, infestation