Combating a Global Threat to a Clonal Crop: Banana Black Sigatoka Pathogen Pseudocercospora fijiensis (Synonym Mycosphaerella fijiensis) Genomes Reveal Clues for Disease Control

• Published in: PLoS genetics 2016-08, Vol.12 (8), p.e1005876-e1005876
• Main Authors: Arango Isaza, Rafael E, Diaz-Trujillo, Caucasella, Dhillon, Braham, Aerts, Andrea, Carlier, Jean, Crane, Charles F, V de Jong, Tristan, de Vries, Ineke, Dietrich, Robert, Farmer, Andrew D, Fortes Fereira, Claudia, Garcia, Suzana, Guzman, Mauricio, Hamelin, Richard C, Lindquist, Erika A, Mehrabi, Rahim, Quiros, Olman, Schmutz, Jeremy, Shapiro, Harris, Reynolds, Elizabeth, Scalliet, Gabriel, Souza, Jr, Manoel, Stergiopoulos, Ioannis, Van der Lee, Theo A J, De Wit, Pierre J G M, Zapater, Marie-Françoise, Zwiers, Lute-Harm, Grigoriev, Igor V, Goodwin, Stephen B, Kema, Gert H J
• Format: Article
• Language: English
• Subjects: Ascomycota - genetics; Ascomycota - pathogenicity; Automation; Bananas; BASIC BIOLOGICAL SCIENCES; Bioint Diagnostics, Food Safety & Phyt. Research; Bioint Entomology & Disease Management; Biointeractions and Plant Health; Biology and Life Sciences; Breeding; Chromosomes, Fungal - genetics; Cladosporium fulvum; Cloning; Colleges & universities; Crop diseases; Disease control; Disease Resistance - genetics; Dothideomycetes; EPS; Farms; Fungi; Gene expression; Genes; Genetic aspects; Genetic diversity; Genetic Variation; Genome, Fungal; Genomes; Genotype; Health aspects; Laboratorium voor Fytopathologie; Laboratorium voor Phytopathologie; Laboratory of Phytopathology; Medicine and Health Sciences; Musa; Musa - genetics; Musa - growth & development; Musa - microbiology; Mycosphaerella fijiensis; Pathogenic fungi; Pathogens; Pesticides; Plant Diseases - genetics; Plant Diseases - microbiology; Plant Leaves - genetics; Plant Leaves - microbiology; Plant-pathogen relationships; Plantations; PPO/PRI Biointeracties en plantgezondheid; PPO/PRI Biointeractions and Plant Health; Prevention; PRI Bioint Diagnostics, Food Safety & Phytosanitary; PRI Bioint Entomology & Disease Management; Pseudocercospora; Retroelements - genetics
• ISSN: 1553-7404; 1553-7390; 1553-7404
• DOI: 10.1371/journal.pgen.1005876

Black Sigatoka or black leaf streak disease, caused by the Dothideomycete fungus Pseudocercospora fijiensis (previously: Mycosphaerella fijiensis), is the most significant foliar disease of banana worldwide. Due to the lack of effective host resistance, management of this disease requires frequent fungicide applications, which greatly increase the economic and environmental costs to produce banana. Weekly applications in most banana plantations lead to rapid evolution of fungicide-resistant strains within populations causing disease-control failures throughout the world. Given its extremely high economic importance, two strains of P. fijiensis were sequenced and assembled with the aid of a new genetic linkage map. The 74-Mb genome of P. fijiensis is massively expanded by LTR retrotransposons, making it the largest genome within the Dothideomycetes. Melting-curve assays suggest that the genomes of two closely related members of the Sigatoka disease complex, P. eumusae and P. musae, also are expanded. Electrophoretic karyotyping and analyses of molecular markers in P. fijiensis field populations showed chromosome-length polymorphisms and high genetic diversity. Genetic differentiation was also detected using neutral markers, suggesting strong selection with limited gene flow at the studied geographic scale. Frequencies of fungicide resistance in fungicide-treated plantations were much higher than those in untreated wild-type P. fijiensis populations. A homologue of the Cladosporium fulvum Avr4 effector, PfAvr4, was identified in the P. fijiensis genome. Infiltration of the purified PfAVR4 protein into leaves of the resistant banana variety Calcutta 4 resulted in a hypersensitive-like response. This result suggests that Calcutta 4 could carry an unknown resistance gene recognizing PfAVR4. Besides adding to our understanding of the overall Dothideomycete genome structures, the P. fijiensis genome will aid in developing fungicide treatment schedules to combat this pathogen and in improving the efficiency of banana breeding programs.