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Selection of botanical and agronomical descriptors for the characterization of cassava (Manihot esculenta Crantz) germplasm^*

Antonio Vander Pereira^I; Roland Vencovsky^II; Cosme Damião Cruz^III

^IEMBRAPA/CNPGL, Rod. MG 133, km 42. 36155 Coronel Pacheco, MG, Brasil. Send correspondence to A.V.P.
^IIESALQ/USP, Departamento de Genética, Caixa Postal 82, 13400 Piracicaba, SP, Brasil
^IIIDepartamento de Biologia, Universidade Federal de Viçosa, 36570 Viçosa, MG, Brasil

ABSTRACT

Several cassava descriptors were studied to evaluate genetic diversity by the use of multivariate analysis. Data on 28 descriptors over 280 accessions from the EMBRAPA's germplasm bank were collected during two crop seasons. The analysis of principal components was used to discard the descriptors which were either redundant or non-discriminating and had a low stability of expression. Through this method it was possible to choose the best 14 descriptors. This reduction in number shall facilitate the characterization of cassava germplasm, without affecting the general information.

Keywords: Manihot esculenta; Germplasm.

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* Part of a thesis presented by A.V.P. to the Departamento de Genética, ESALQ-USP, in partial fulfilhnent of the requirements for the Doctoral degree.