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Sweet cassava breeding programs are focused on the development of bio fortified cultivars that combine significant amounts of carotenoids in their reserve roots with desirable agronomic. The objective of this research was to evaluate agronomic and biochemical traits in sweet cassava clones with roots that have pink pulp. The nine genotypes were evaluated in two seasons in a randomized block design with three replications. Among the evaluated clones, the following stood out: i) for the height of the first branch (390/08, 345/08 and the control IAC 576-70); ii) for plant height (390/08, 345/08 e 378/08); iii) for shoot weight without original steam cutting (390/08, 406/08, 378/08 e 341/08); iv) for the percentage of starch in roots (378/08, 413/08, 390/08 and the control IAC 576-70); and v) for the root yield (the control IAC 576-70 and 341/08, 390/08, 406/08 e 387/08). In the 2011/2012 season, all clones cooked within 30 minutes, indicating that they all have good culinary qualities. Regarding the total carotenoid content in the roots, the clones that stood out were 406/08 and 341/08. All clones evaluated had HCN content below 100 mg kg-1. Clones 341/08 and 406/08 have agronomic and biochemical potential for direct cultivation by producers in the Cerrado region of Central Brazil and / or for use as stock in sweet cassava breeding programs. [ABSTRACT FROM AUTHOR]

Cassava is cultivated for two ends proposals: "sweet cassava" as fresh consumes and "industry cassava" as source of starch and farina. Landraces were used to discover "spontaneous mutations" and to develop evolutionary and breeding perspective of gene function. Genomic and Proteomic resources were obtained. Gene expression by RNA blot and Microarray analysis were performed to identify differentially expressed genes. A new sugary cassava was identified to be related to missing expression of BEI and a nonsense mutation in GBSSI gene leading to amylose free starch. A pink phenotype showed no expression of CasLYB gene, and a yellow phenotype a down regulation of CasHYb. Proteomic analysis of carotenoid-protein complex together with gene expression analysis of CAP4 revealed a heteroduplex double strand cDNA associated with high carotenoid content. GBSSI gene sequencing identified 22 haplotypes and large nucleotide diversity. Segregating populations by crossing differential biochemical phenotypes and parents adapted to Cerrado's Region were obtained. [ABSTRACT FROM AUTHOR]