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Path analysis of yield components of cacao hybrids (Theobroma cacao L.)^*

Caio Márcio Vasconcellos Cordeiro de Almeida^I; Roland Vencovsky^II; Cosme Damião Cruz^III; Basil G.D. Bartley^IV

^IRua Salgado Filho 2595, São Cristovão, 78902-550 Porto Velho, RO, Brasil. Send correspondence to C.M.V.C.A.
^IIDepartamento de Genética, ESALQ/USP, Caixa Postal 83, 13418-900 Piracicaba, SP, Brasil
^IIIDepartamento de Biologia Geral, Universidade Federal de Viçosa, 36570-000 Viçosa, MG, Brasil
^IVApartado 123, 2780 Oeiras, Portugal

ABSTRACT

Genotypic correlations and their direct and indirect effects were estimated for ten traits of 12 cacao hybrids using path analysis. A high coefficient of genotypic correlation was found between trunk height and bean dry weight/tree. However, path analysis revealed that trunk height had a negative direct effect on yield. The number of healthy fruits/tree and dry bean weight/fruit should be considered as the main yield components because these traits showed direct effects of high value on dry bean weight/tree. The number of seeds/fruit and bean dry weight constituted the main components of dry bean weight/fruit. Since these traits showed direct and indirect effects of high value, they should be considered as secondary yield components.

Keywords: path analysis; yield components; cacao hybrids; Theobroma cacao L.

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* Part of a thesis presented by C.M.V.C.A. to ESALQ/USP in partial fulfillment of the requirements for the Doctoral degree.