title: Population Structure of Xylella fastidiosa Associated with Almond Leaf Scorch Disease in the San Joaquin Valley of California.
abstract: Xylella fastidiosa causes disease in many commercial crops, including almond leaf scorch (ALS) disease in susceptible almond (Prunus dulcis). In this study, genetic diversity and population structure of X. fastidiosa associated with ALS disease were evaluated. Isolates obtained from two almond orchards in Fresno and Kern County in the San Joaquin Valley of California were analyzed for two successive years. Multilocus simple-sequence repeat (SSR) analysis revealed two major genetic clusters that were associated with two host cultivars, 'Sonora' and 'Nonpareil', respectively, regardless of the year of study or location of the orchard. These relationships suggest that host cultivar selection and adaptation are major driving forces shaping ALS X. fastidiosa population structure in the San Joaquin Valley. This finding will provide insight into understanding pathogen adaptation and host selection in the context of ALS disease dynamics.
authors: First, second, and fourth authors: United States Department of Agriculture-Agricultural Research Service (USDA-ARS) San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA 93648-9757; second author: Department of Viticulture and Enology, University of California, Davis 95616; third author: Universidad Privada Antenor Orrego, Trujillo, Perú; and fifth author: Department of Entomology, University of Wisconsin, Madison 53706.
authors: Hong
authors: H
authors: Lin
authors: First, second, and fourth authors: United States Department of Agriculture-Agricultural Research Service (USDA-ARS) San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA 93648-9757; second author: Department of Viticulture and Enology, University of California, Davis 95616; third author: Universidad Privada Antenor Orrego, Trujillo, Perú; and fifth author: Department of Entomology, University of Wisconsin, Madison 53706.
authors: Md Sajedul
authors: MS
authors: Islam
authors: First, second, and fourth authors: United States Department of Agriculture-Agricultural Research Service (USDA-ARS) San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA 93648-9757; second author: Department of Viticulture and Enology, University of California, Davis 95616; third author: Universidad Privada Antenor Orrego, Trujillo, Perú; and fifth author: Department of Entomology, University of Wisconsin, Madison 53706.
authors: Juan C
authors: JC
authors: Cabrera-La Rosa
authors: First, second, and fourth authors: United States Department of Agriculture-Agricultural Research Service (USDA-ARS) San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA 93648-9757; second author: Department of Viticulture and Enology, University of California, Davis 95616; third author: Universidad Privada Antenor Orrego, Trujillo, Perú; and fifth author: Department of Entomology, University of Wisconsin, Madison 53706.
authors: Edwin L
authors: EL
authors: Civerolo
authors: First, second, and fourth authors: United States Department of Agriculture-Agricultural Research Service (USDA-ARS) San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA 93648-9757; second author: Department of Viticulture and Enology, University of California, Davis 95616; third author: Universidad Privada Antenor Orrego, Trujillo, Perú; and fifth author: Department of Entomology, University of Wisconsin, Madison 53706.
authors: Russell L
authors: RL
authors: Groves
mesh_terms: D002140:California; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000235:genetics; D014644:Genetic Variation; D005828:Genetics, Population; D018895:Microsatellite Repeats / Q000235:genetics; D010935:Plant Diseases / Q000382:microbiology*; D018515:Plant Leaves; D016133:Polymerase Chain Reaction; D027861:Prunus / Q000382:microbiology*; D044167:Xylella / Q000235:genetics* / Q000302:isolation & purification
chemical_list: D004269:DNA, Bacterial
keywords: annual variation