Esterase isozymes for the characterization of "unnamed" cassava cultivars (<em>Manihot esculenta</em> Crantz)

Abstract

Esterase isozymes were used as molecular markers to discriminate and cluster seven "unnamed" cultivars (accesses A-G) of M. esculenta. The "unnamed" cassava cultivars were compared to 25 different M. esculenta cultivars (cultivars BG), which have been maintained in the germplasm collection of the Agronomy Department, State University of Maringá. 4-Methylumbelliferyl acetate, 4-methylumbelliferyl propionate and α–naphthyl acetate were utilized as substrates for isoesterase detection and comparative analysis. Similarity between plants, using Jaccard’s coefficient, ranged from 47.6% to 100%. A dendrogram produced by cluster analysis showed identity between cultivar BG 23 and plants of accession D. Plants of accesses B and G were also clustered with cultivar BG 23 showing 95% and 89% similarity, respectively. Plants of accesses A and E were similar to BG 1, showing 95% and 90% similarity, respectively. Plants of accession F were clustered with cultivar BG 9, showing 94% similarity. The dendrogram also showed that most of the cultivars were clustered together with 85-90% similarity. Thus, we conclude that esterase isozymes may be used as molecular markers of cassava genotypes for the characterization of “unnamed” cultivars of M. esculenta