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Fusarium and Lasiodiplodia species invade feeding lesions caused by mirid bugs (Distantiella theobroma [Dist.] and Sahlbergella singularis Hagl.) and inflict serious damage and yield loss to susceptible cacao (Theobroma cacao L.) varieties in West Africa. As it is the fungal invasion rather than the physical feeding injury by mirids that cause dieback and tree death in cacao, a dieback resistance strategy in cacao crop must take into account resistance to these causal agents. Twenty-nine and 15 cacao genotypes were screened in the laboratory and the greenhouse, respectively, for resistance to isolates of Fusarium decemcellulare and Lasiodiplodia theobromae at Imperial College London's Biological Sciences Campus, UK. Resistance was assessed as the size of necrotic lesions, distance of fungal colonisation in the stem and the proportion of seedlings with dieback symptoms. Genotypic differences were found in both laboratory and greenhouse tests among various cacao genotypes, and the clones showed a wide range of disease reactions from highly resistant to very susceptible. The pathogenicity of F. decemcellulare and L. theobromae were similar in this study, which suggests that a breeding programme for controlling one of the pathogens can have benefit against the other. Direct significant correlations (r = 0.7) were obtained between visual dieback assessment scores and the percentage cross-sectional area of stem necrosis. Moreover, the response of inoculated stem segments corresponded to the reaction of intact plants despite the variation in the used methodology. Three cacao genotypes (CATIE 1000, T85/799 and MXC 67) were resistant or moderately resistant to F. decemcellulare and L. theobromae. These genotypes could be useful sources of resistance to both pathogens and other wilt causing pathogens in cacao.


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Corresponding author. Email:; Present address: Cocoa Research Institute of Ghana, PO Box 8, Tafo-Akim, Ghana.


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Adu-Acheampong, R. (2009). Pathogen diversity and host resistance in dieback disease of cocoa caused by Fusarium decemcellulare and Lasiodiplodia theobromae. PhD thesis, Imperial College London, 192 pp.
Adu-Acheampong, R. and Ackonor, J. B. (2005). The effect of imidacloprid and mixed pirimiphos-methyl and bifenthrin on non-target arthropods of cocoa. Tropical Science 45 (4):153154.
Baah, F. and Garforth, C. (2008). Insights into cocoa farmers’ attitudes in two districts of Ashanti, Ghana. International Journal of Sustainable Development 1 (3):814.
Brownlee, H. E., McEuen, A. R., Hedger, J. and Scott, I. M. (1990). Antifungal effects of cocoa tannin on the witches’ broom pathogen Crinipellis perniciosa. Physiological and Molecular Plant Pathology 36:3948.
Capriles de Reys, L. and Reys, H. E. (1968). Contenido de polifenoles en dos variedades de Theobroma cacao L. y su relacion con la resistencia a Ceratocystis fimbriata. Agronomia Tropical 18;339355.
Capriles de Reys, L., Schulz, E. S. and Munoz, A. (1964). El contenido de acido clorogenico con diferentes variedades de cacao y su relacion con la resistencia contra el hongo Ceratocystis fimbriata. Agronomia Tropical 16:273284.
Cooper, R. M., Resende, M. L. V., Flood, J., Rowan, M. G. and Beale, M. H. (1995). Detection and cellular localisation of elemental sulphur in disease resistant genotypes of Theobroma cacao. Nature 379:159162.
Crowdy, S. H. (1947). Observations on the pathogenicity of Calonectria rigidiuscula (Berk and Br.) Sacc. on Theobroma cacao L. Annals of Applied Biology 34:4549.
Danquah, O. A. (1986). Growth of Crinipellis perniciosa in cocoa resistant and susceptible to Witches’ broom. PhD thesis, University of London.
Dungeon, G. C. (1910). Notes on two West African Hemiptera injurious to cocoa. Bulletin of Entomological Research 1:5961.
Entwistle, P. F. (1972). Pests of Cocoa. London: Longman, 779 pp.
Evans, H. C. and Bastos, , , C. N. (1975). Basidiospore germination as a means of assessing resistance to Crinipellis perniciosa (Witches’ broom disease) in cocoa Theobroma cacao cultivars. Transactions of the British Mycological Society 74 (3):525536.
Nojosa, G. B. A., Resende, M. L. V., Aguilar, M. A. G., Bezerra, K. M. T. and Anhert, D. E. (2003). Componentes fenólicos enzimas oxidativas em clones de Theobroma cacao resistantes e suscetíveis a Crinipellis perniciosa. Fitopatologia Brasileira 28:148154.
Owen, H. (1956). Further observations on the pathogenicity of Calonectria rigidiuscula (Berk and Br.) Sacc. to Theobroma cacao L. Annals of Applied Biology 44 (2):307321.
Padi, B., Downham, M., Farman, D. I. and Sarfo, J. E. (2001). Evidence of sex attractants in the cocoa mirids Distantiella theobroma (Dist) and Sahlbergella singularis Hagl. (Heteroptera: Miridae) in field-trapping experiments. In: Proceedings of the 13th International Cocoa Research Conference, Kota Kinabalu, Saba, Malaysia, 9–14 October 2000. Cocoa Producers’ Alliance, pp. 395–402.
Resende, M. L. V., Flood, J., Ramsden, J. D., Rowan, M. G., Beale, M. H. and Cooper, R. M. (1996). Novel phytoalexins including elemental sulphur in the resistance of cocoa (Theobroma cacao L.) to Verticillium wilt (Verticillium dahliae Kleb.). Physiological and Molecular Plant Pathology 48:347359.
Sacristan, M. D. (1982). Resistance responses to Phoma lingam of plants regenerated from selected cell and embryogenic cultures of haploid Brassica napus. Theoretical and Applied Genetics 61:193200.
SAS Institute Inc. (2007). SAS/STAT User's Guide version 9.1.3 Cary. NC: SAS Institute.
Sokal, R. R. and Rohlf, F. J. (1995). Biometry: The Principles and Practice of Statistics in Biological Research, 3rd edn.New York: W. H. Freeman, 887 pp.
Stack, R. W. (1989). Comparison of inoculum potential of ascospores and conidia of Gibberella zeae. Canadian Journal of Plant Pathology 11:137142.
Surujdeo-Maharaj, S., Umaharan, P. and Butler, D. R. (2004). Assessment of resistance to Witches’-broom disease in clonal and segregating populations of Theobroma cacao. Plant Disease 88:797803.
Thevenin, J. M., Umaharan, R., Surujdeo-Maharaj, S., Latchman, B., Cilas, C. and Butler, D. R. (2005). Relationships between black pod and Witches’-broom diseases in Theobroma cacao. Phytopathology 95 (11):13011307.
Verica, J. A., Maximova, S. N., Strem, M. D., Carlson, J. E., Bailey, B. A. and Guiltinan, M. J. (2004). Isolation of ESTs from cocoa (Theobroma cacao L.) leaves treated with inducers of the defence response. Plant Cell Reports 23:404413.
Williams, G. (1953). Field observations on the cacao mirids Sahlbergella singularis Hagl. and Distantiella theobroma (Dist.), in the Gold Coast. Part I. Mirid damage. Bulletin of Entomological Research 44:101119.


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