Practices and damages encountered by wholesale traders during '<i>Kponan</i>' yams (<i>Dioscorea cayenensis-rotundata</i>) storage in Abidjan, Côte d'Ivoire

Abstract

Yam wholesalers who practice speculative storage sometimes suffer significant losses the level of which has been little studied. Thus, this work was carried out to study the practices and deterioration factors of 'Kponan' yam during storage. To achieve this, 51 yam wholesalers in 4 communes of Abidjan (Abobo, Adjamé, Yopougon and Treichville) were interviewed using a survey form. The data showed that according to storage practices, yams are preferentially grouped by variety (100%) and old yams separately (88.2%). Wholesalers (94.1%) regulate the storage temperature either by fans (23.5%), by air openings in the wall (25.5%), or by fans and air openings in the wall (45.1%). Decay was the most common damage among all wholesalers (100%), followed by weight loss (52.9%), mold (35.3%), injury (29.4%), cracking (23.5%), and sprouting (17.6%). Heat was the main cause of yam damage, followed by moisture (82.3%), animals (31.4%), field storage conditions (17.6%), chemical use during cultivation (17.6%) and sprouting (17.6%). This study shows that the storage and temperature control techniques employed by wholesalers are far from mitigating the heat that is the main cause of damage to 'Kponan' yam (Dioscorea Cayenenis-rotundata) during storage.