Abstract
The objective of this study was to assess five cacao cultivars (selfs) and 20 hybrids with regard to their general-and specific-combining ability for yield components using method 1, model I, of the diallel analysis system. The selfings and the hybrids were obtained through controlled crossings, tested in the field in a random block design with four replications and plots containing 16 plants. The experiment was set up in the Centro de Pesquisas do Cacau, in Itabuna, Bahia, Brasil, in 1975. The characteristics studied were: the number of healthy and collected fruits per plant (NHFP and NCFP), the weight of humid seeds per plant and per fruit (WHSP and WHSF), and the percentage of diseased fruits per plant (PDFP), for 5 years (1986–1990). The F-test values, highly significant for general combining ability (GCA) and specific combining ability (SCA), demonstrated the existence of variability for both effects. However, the effects of SCA were greater than those of GCA, when compared in terms of the average squared effects. This condition held for the characteristics NHFP, NCFP and WHSP, which shows the relative importance of the non-additive genetic effects over the additive effects. The reciprocal effects did not show significance. Breeding methods which explore the additive portion of genetic variance should be employed for obtaining higher-yielding cacao and high seed weight. For this, the segregant populations should involve cultivars CEPEC 1, SIAL 169 and ICS 1. Combinations involving the cultivar ICS 1 presented the most favorable results for the characteristics WHSP and WHSF, where the hybrid SIAL 169 x ICS 1 and its reciprocal were outstanding.
Similar content being viewed by others
References
Atanda OA (1973) Heterosis in crosses of Theobroma cacao. Exp Agric 9:23–29
Atanda OA, Toxopeus H (1971) A proved case of heterosis in Theobroma cacao L. In: Proc 3rd Int Cocoa Res Conf, CRIN, Tafo, pp 545–551
Baez OL (1984) Herencia de ciertos caracteres de la semilla del cacao (Theobroma cacao). MS thesis. Universidad de Costa Rica, San Jose, Costa Rica
Baker RJ (1978) Issues in diallel analysis. Crop Sci 18:533–536
Bartley BGD (1969) Twenty years of cacao breeding at the Imperial College of Tropical Agriculture, Trinidad. In: Proc 2nd Int Cocoa Res Conf, CEPLAC, Itabuna, Brasil, pp 29–34
Bartley BGD (1970) Yield variation in the early productive years in trials with cacao (Theobroma cacao L.). Euphytica 19:199–206
Bartley BGD (1971) First generation inbreds as parents in hybrids of Theobroma cacao L. Trop Agric 48:79–84
Carletto GA, Garcia JR, Magalhães WS (1977) Evaluation de hibridos y lineas endocriadas de cacao en Bahia. In: Proc 5th Intl Cocoa Res Conf, CRIN, Ibadan, pp 106–109
Cruz CD, Vencovsky R (1989) Comparação de alguns métodos de análise dialélica. Braz J Genet 12:425–438
Engels JMH (1985) A systematic description of cacao clones. V. Quantitative genetic aspects of several fruit characters. Café Cacao Thé 29:3–10
Griffing B (1956) Concept of general and specific combining ability in relation to the diallel crossing system. Aust J Biol Sci 9:463–493
Mariano AH, Bartley BGD (1981) Comportamento das seleções baianas na produção de cacaueiro. In: Proc 7th Int Cocoa Res Conf, J de Lafforest and Transla-Inter, Douala, pp 527–533
Monteiro WR, Carletto GA, Bartley BGD (1985) Avaliação da capacidade combinatória de clones de cacaueiro. In: Proc 9th Int Cocoa Res Conf, Cocoa Producers' Alliance, Lomé, pp 227–232
Mora LGR (1987) Herencia de ciertos caracteres de la mazorca y del arvol de cacao (Theobroma cacao). MS thesis. Universidad de Costa Rica, San Jose, Costa Rica
Ojo AA (1982) A partial diallel evaluation of selected Theobroma cacao clones. In: Proc 8th Int Cocoa Res Conf, Cocoa Producers' Alliance, Cartagena, pp 667–671
Pardo J, Enriquez GA (1988) Herencia de algunos componentes de la calidad industrial en almendras de cacao (Theobroma cacao). In: Proc 10th Int Cocoa Res Conf, Cocoa Proceducers' Alliance, Santo Domingo, pp 695–699
Pereira MG, Carletto GA, Dias LAS (1987) Avaliação de hibridos de cacaueiros nas condições de Linhares-ES. Bol Técnico 150
Soria J (1963) Observaciones sobre las variedades y cultivares de cacao en Bahia, Brasil. Cacao 8:1–6
Soria J, Esquivel O (1969) Algunos resultados del programa de mejoramiento genetico de cacao en el IICA-Turrialba. In: Proc 2nd Int Cocoa Res Conf, CEPLAC, Itabuna, Brasil, pp 35–42
Soria J, Ocampo F, Paez G (1974) Parental influence of several cacao clones on the yield performance of their progenies. Turrialba 24:58–65
Sprague GF, Tatum LA (1942) Generalvs specific-combining-ability in single crosses of corn. J Am Soc Agron 34:923–932
Tan GY (1990) Combining ability analysis of yield and its components in cacao. J Am Soc Hort Sci 115:509–512
Vello F, Mariano AH, Garcia JR, Nascimento TF, Magalhães WS (1969) O programa de melhoramento genetico do cacau na Bahia. In: Proc. 2nd Int Cocoa Res Conf, CEPLAC, Itabuna, Brasil, pp 43–56
Vencovsky R, Barriga P (1992) Genetica biometrica no fitome-1 jhoramento. RBG, Ribeirão Preto, São Paulo
Author information
Authors and Affiliations
Additional information
Communicated by P. M. A. Tigerstedt
Rights and permissions
About this article
Cite this article
Dias, L.A.S., Kageyama, P.Y. Combining-ability for cacao (Theobroma cacao L.) yield components under southern Bahia conditions. Theoret. Appl. Genetics 90, 534–541 (1995). https://doi.org/10.1007/BF00222000
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00222000