ARS | Publication request: Genetic comparison of two related fungal pathogens of Theobroma cacao

Submitted to: International Conference on Microbial Genomes
Publication Type: Proceedings
Publication Acceptance Date: August 27, 2007
Publication Date: September 16, 2007
Citation: Meinhardt, L.W., Bailey, B.A., Guiltinan, M., Pereira, G.A. 2007. Genetic comparison of two related fungal pathogens of Theobroma cacao. International Conference on Microbial Genomes.

Technical Abstract: Theobroma cacao (cacao) is the source of cocoa and cocoa butter, which are used in the manufacturing of chocolate. Cacao production in South America is limited mainly by two fungal pathogens, Moniliophthora roreri and Moniliophthora perniciosa. These pathogens cause frost pod rot (FPR) and Witches’ broom disease (WBD), respectively. Until recently, these fungi were in different genera but now are considered sister taxa. A partial genome sequence of M perniciosa, which contains 78 Mbp has been completed by the Laboratório de Genômica e Expressão - LGE at the University of Campinas. Comparative Blast searches for several gene sequences of M. roreri reveal that gene homology for EF-1 alpha was 92% identical with 1% gaps; RPB1 proved to be 94% identical with 0% gaps; the 28S subunits was 97% identical with 0% gaps; the 18S subunit was 98% identical with 0% gaps and the 5.8S subunit was 100% identical. Due to the clear relatedness of these two fungi we have started a project to completely sequence both genomes and utilize those data to develop comparative genomic analyses of these fungal pathogens. The 454 sequencing system will be used to generate the sequences and the partial M. perniciosa genome will be utilized to align the sequence data.