Effect of Harvest Period on Starch Yield and Dry Matter Content from the Tuberous Roots of Improved Cassava (Manihot esculenta Crantz) Varieties

Abstract

The aim of this study was to evaluate the variation of starch yields and dry contents from the tuberous roots of five improved cassava varieties ("Bonoua2", "Ay15", "971A", I88/00158 and "90/00039") at different harvest periods (11, 13, 15 and 17 months after planting). Indeed, the harvest period had significant effect at 0.05 level on dry matter contents and starch yields. All improved cassava varieties had their peak of dry matter contents (40.57%±2.41) and starch yields (20.17%±2.82%) at 13 months after planting. The tuberous roots of "Bonoua2" improved cassava variety had the highest starch yields at 11, 13 and 15 months after planting, with the respective values of 18.26%±1.52%, 20.78%±2.57% and 18.08%±3.18% respectively. Concerning the highest starch yield at 17 months after planting, it was obtained with "971A" improved cassava variety (19.38%±2.55%). The tuberous roots of "Bonoua2" improved cassava variety detained also the highest dry matter contents at 11 and 15 months after planting. The values were of 39.83%±1.19% and 38.70±2.61% respectively. As for the highest dry contents at 13 and 17 month after planting, they were given by the tuberous roots of "971A" improved cassava variety, with the respective values of 42.99%±1.48% and 39.04%±2.57%.