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Use of numerical taxonomy to compare "Mocó" Cotton with other Cotton species and races

José de Alencar Nunes Moreira; Elêusio Curvelo Freire; José Wellington dos Santos, Robson Macêdo Vieira

Centro Nacional de Pesquisa do Algodão (CNPA), EMBRAPA, Caixa Postal 174, 58107-720 Campina Grande, PB, Brasil. Send correspondence to J.A.N.M.

ABSTRACT

"Mocó" Cotton (Gossypium hirsutum r. marie galante Hutch), is grown in Northeastern Brazil, but its origin is unknown. The objective of our study was to compare mocó with other cotton species and races to clarify its origin and botanical classification. The study was conducted on G. hirsutum r. marie galante Hutch (exotic), G. barbadense var. brasiliense, the "verdão" (green) types of G. hirsutum L., and the cotton plants generally known under the mocó name and represented by cream fiber, Francisco Raimundo; "mocó das Serras" (highland mocó) from the Seridó Valley, "mocozinho", and, finally, improved mocó. The variables chosen for study were leaf, bract, and flower traits measured in five plants selected at random before flowering. The methodology consisted of the use of cluster analysis, principal coordinates, canonical discriminant analysis and linear discriminant functions. The results favor the hypothesis that the mocó cotton lineage consists of several trunks rather than a single one, and that the "mane galante" race is one of them.

Keywords: numerical taxonomy; "Mocó" Cotton.

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