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ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Sustainable Perennial Crops Laboratory » Research » Publications at this Location » Publication #401664

Research Project: Development of Pathogen- and Plant-Based Genetic Tools and Disease Mitigation Methods for Tropical Perennial Crops

Location: Sustainable Perennial Crops Laboratory

Title: A draft genome resource for Marasmius tenuissimus, an emerging causal agent of thread blight disease in cacao

item LEUNG, JASON - Orise Fellow
item Cohen, Stephen
item BARUAH, INDRANI - Orise Fellow
item ALI, SHAHIN - University Of California, Davis
item Shao, Jonathan
item BUKARI, YAHAYA - Cocoa Research Institute Of Ghana
item AMOAKO-ATTAH, ISHMAEL - Cocoa Research Institute Of Ghana
item Meinhardt, Lyndel
item Bailey, Bryan

Submitted to: PhytoFrontiers
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/17/2023
Publication Date: 4/17/2023
Citation: Leung, J., Cohen, S.P., Baruah, I., Ali, S., Shao, J.Y., Bukari, Y., Amoako-Attah, I., Meinhardt, L.W., Bailey, B.A. 2023. A draft genome resource for Marasmius tenuissimus, an emerging causal agent of thread blight disease in cacao. PhytoFrontiers.

Interpretive Summary: Plant diseases are a leading source of economic loss in agriculture. Cacao trees, the crop used for chocolate production, are threatened by thread blight disease. A fungal pathogen has recently been identified as the primary pathogen responsible for this disease. In this work, we sequenced the genome of this pathogen and described its features in detail. We identified potential features of the genome that may be important for pathogen virulence. Releasing this genome allows plant pathologists to know more about how this pathogen causes thread blight disease in cacao trees and will help them develop strategies for controlling the disease.

Technical Abstract: Thread blight disease (TBD) is a serious emerging threat to global cacao production, causing leaf blight symptoms and necrosis in the canopy of infected trees. Though previously thought to be caused primarily by the fungus Marasmiellus scandens, recent work has revealed that a variety of pathogenic Marasmiaceae are responsible for TBD, with Marasmius tenuissimus identified as the dominant causal agent of TBD in Ghanaian cacao plantations. M. tenuissimus has also been reported in remote organic cacao plantations in the Amazonas Department of Peru, infecting 90-100% of the trees surveyed. Previously, the mitochondrial genome was characterized for M. tenuissimus and five other TBD-causing members of the Marasmiaceae. Here we have assembled and annotated the nuclear genome of M. tenuissimus isolate GH-37. This resource is the first high-quality draft genome for M. tenuissimus and extends the current understanding of the evolution, ecology, and virulence of this pathogen.