Effect of Storage Condition and CIPC Treatments on Sprouting and Weight Loss of Stored Yam Tubers.

Abstract

In this study, two storage conditions and two different pre-storage treatments in yam storage were evaluated. The storage conditions were two traditional yam barns; with a fan placed in one of them to aid air flow, with no fan in the other. The pre-storage treatments used were chloro Isopropyl phenyl carbamate (CIPC) solution in four levels and CIPC powder in four levels. A total of eighty-four tubers of yam, Giwa variety (Dioscorea rotundata) were stored in each barn for six months. Parameters evaluated were temperature, relative humidity, weight loss, rate of sprouting and rot development. The results showed that the temperature in barn with forced air circulation fluctuated between 20.5 and 350C with an average of 300C while that in the barn without forced air circulation fluctuated between 23 and 390C with an average of 320C over the six months period of the experiments. The relative humidity in the barn with forced air circulation ranged between 25 and 60% with an average of 43%, while that in the barn without forced air circulation ranged between 28 and 61% with an average of 43% over the same period. The tubers in the barn with forced air circulation showed less sprout weights and less weight loss than those stored in the barn without forced air circulation throughout the period of storage. At the end of a three-month period, the tubers in the ventilated barn showed 4.7% less weight loss than comparable tubers receiving no controlled air flow. The CIPC chemicals (powder and solution) at all levels did not have any effect in suppressing sprouting in dioscorea rotundata, neither did they show visible effect on rot in the stored yam tubers. However, the barn with forced air circulation had 1.85% rottened tubers while 12.05% in the barn without forced air circulation were rotten.