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ARS Home » Southeast Area » Byron, Georgia » Fruit and Tree Nut Research » Research » Publications at this Location » Publication #375528

Research Project: Healthy, Sustainable Pecan Nut Production

Location: Fruit and Tree Nut Research

Title: Development of a Venturia Effusa Pangenome to Aid in Identification of Cultivar Specificity Genes

item SHILLER, JASON - Noble Research Institute
item Bock, Clive
item CHARLTON, NIKKI - Noble Research Institute
item KROM, NICK - Noble Research Institute
item ALARCON, YANINA - Noble Research Institute
item MONTEROS, MARLA - Noble Research Institute
item GRAHAM, CHARLIE - Noble Research Institute
item YOUNG, CAROLYN - Noble Research Institute

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 5/13/2020
Publication Date: 12/1/2020
Citation: Shiller, J.B., Bock, C.H., Charlton, N.D., Krom, N., Alarcon, Y., Monteros, M., Graham, C., Young, C.A. 2020. Development of a Venturia effusa pangenome to aid in identification of cultivar specificity genes. Meeting Abstract. Vol 110, S2.191.

Interpretive Summary: Abstract Only.

Technical Abstract: The most destructive disease of pecan (Carya illinoinensis) in the southeastern U.S. is scab, caused by Venturia effusa. Symptoms include lesions on nuts, leaves and shoots, reducing overall yield. Growers rely heavily on fungicide use to control the disease, applying ten or more sprays per season. Resistant varieties of pecan exist but are not widely grown. Neither the durability nor the mechanism of resistance are known. Multiple races of V. effusa have been identified that have cultivar specificities and these interactions are likely to be governed by gene-for-gene interactions similar to those observed in other Venturia species (e.g., V. inaequalis, the apple scab pathogen). We used comparative genomics to identify genes in V. effusa involved in cultivar specificity. The genomes of 11 isolates of V. effusa were sequenced and assembled, including a full-length chromosome level assembly. The isolates represent five pecan cultivars from five growing regions, and two isolates from native Carya spp. A V. effusa pangenome was built and characterized. Based on other systems, genes involved in plant-host interactions were identified, including small secreted proteins, carbohydrate active enzymes (CAZymes) and gene clusters involved in secondary metabolism. We also incorporated meta-transcriptome data from naturally infected pecan in the field to enable candidate gene identification for host-cultivar specificity. The analysis will provide a basis for wider studies at the population level to identify key genes that determine host specificity.