Improving Pit Storage Systems to Reduce Rots of Whiteyam (Dioscorea rotundata) In Ghana

2015

English

Harvested tubers stored in dug pits (a common practice in Wenchi Municipal, Ghana) are prone to rot infections by soil-borne pathogens. Improving this system would go a long way to ensure food security and increased returns of yam growers and actors along the food chain.Efficacies of two chemical fungicides, Shavit F71.5 WP and Metalaxyl Mancozeb WP, in protecting buried whiteyams(‘dente’ and ‘pona’) tubers against rots were investigated.Healthy looking tubers were sprayed with the two chemical fungicides, dried and buried in dug pits using CRD design (3 replicates). Control was set-up with no application of fungicides on healthy tubers. Pits were further covered with cut vegetation and soil. After fourteen weeks, the tubers were exhumed when signs of sprouting were observed. Tubers were randomly sampled from each pit and the number of unrotten and rotten tubers recorded. Data was subjected to statistical analysis(ANOVA) and Decay Reduction Index (DRI) to determine significance due to the treatments in reducing yam tuber rots and effectiveness of fungicides in controlling yam rot respectively. There was significant differences between the fungicides and control (P<0.05). Shavit WP had a DRI of 0.71 whilst Met. Mancozeb WP had 0.46 for ‘dente’. DRI values recorded for ‘pona’ were 0.84 and 0.79 for Shavit WP and Met. Mancozeb WP respectively. Both fungicides are effective in controlling rots during post-harvest storage but Shavit WP is more potent. In order to improve shelf life of tubers and seed yams, coating surfaces with appropriate fungicides before burying is recommended.

Aidoo, A. K.