Chemical root traits differentiate ‘bitter’ and ‘sweet’ cassava accessions from the Amazon
Francisca das Chagas Bezerra de Araújo, Elisa Ferreira Moura, Roberto Lisboa Cunha, João Tomé de Farias Neto and Rodrigo de Souza Silva
Abstract: ‘Bitter’ and ‘sweet’ cassava are normally distinguished based on the hydrocyanic acid (HCN) content of their roots. Moreover, Brazilian farmers tend to select ‘sweet’ cassava based on the taste and cooking aspects. The aim of this study was to characterize chemical traits of ‘bitter’ and ‘sweet’ cassava roots of the Amazon region and to find genetic relations among accessions based on these traits. Considerable phenotypic variation was detected among the evaluated traits moisture, ashes, total soluble solids, total titratable acidity, pH, total carotenoids, free and total cyanide, crude protein, glucose, fructose, sucrose and starch. Aside from free and total cyanide, the trait means of sugars and moisture differed in ‘bitter’ and ‘sweet’ cassava and also differentiated these in different clusters in the dendrogram using the unweighted pair-group method based on arithmetic averages (UPGMA) and in the results of principal component analysis.