Variability in Starch Content, Starch Granule Morphology and Size Distribution of Three Cassava (Manihot esculenta) Genotypes in Relation to Yield, at Different Planting Seasons

Background: Investigation of the biochemical profile and storage root yield of three cassava genotypes (H-165, H-226 and TME-419) was carried out. Planting was done at three different seasons: summer, early monsoon and late monsoon. Methods: The storage roots were harvested at intervals of 6, 9 and 12 months after planting to evaluate their yield. Granule morphology of the starches and biochemical characteristics of the flours were examined using electron microscopy and biochemical techniques. Result: Significant variations were observed in the starch content, root yield and size of starch granule, which were mainly dependent on planting dates, while the variations recorded in starch granule morphology, amylose and amylopectin contents were influenced by genotype. The highest starch (33.5%) and amylose content (18.9%) were observed in TME-419 variety. The rate of storage root yield had positive correlation with maximum temperature and sunshine and negative correlation with humidity and rainfall. This study indicated that cultivation season affects starch accumulation and root yield in cassava and can be applied in developing cassava varieties with high starch and root yield, suitable for different planting seasons.