Phenotypic variability in Manihot esculenta Crantz flowers in northern Mato Grosso

Abstract

The characterization of ethnovarieties of cassava cultivated by family farmers is essential for the selection of superior genotypes in breeding programs of the species. The aim of this study was to evaluate the genetic variability of 15 ethnovarieties of cassava cultivated in the municipality of Alta Floresta, Mato Grosso, via the morphological descriptors of the flowers. For the characterization, eight qualitative and quantitative morphological descriptors were used, as described for the species Manihot esculenta. The manioc flowers (female and male) showed variability in the color of the ovary, disc and sepals. Female flowers have varied sizes, from 7.12 to 9.03 mm in length and in width from 2.80 to 3.72 mm. For the male flowers, the variation in length was from 6.43 to 8.12 mm and width from 2.61 to 3.61 mm. The UPGMA grouping, using a cut-off point of 75.74%, allowed for the formation of two genetic groups, of which the first group (GI) was composed of 86.67% of the evaluated ethnovarieties and the second group (GII) was composed by 13.33%. The floral characteristics were efficient for use in phenotypic differentiation and show genetic variability among the ethnovarieties.