UMD Theses and Dissertations

Permanent URI for this collectionhttp://hdl.handle.net/1903/3

New submissions to the thesis/dissertation collections are added automatically as they are received from the Graduate School. Currently, the Graduate School deposits all theses and dissertations from a given semester after the official graduation date. This means that there may be up to a 4 month delay in the appearance of a given thesis/dissertation in DRUM.

More information is available at Theses and Dissertations at University of Maryland Libraries.

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Author: search.filters.author.Harris, Jordan LeeSubject: search.filters.subject.Population

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    Epidemiology and population structure of Xylella fastidiosa, the causal agent of bacterial leaf scorch, among urban trees in the District of Columbia
    (2014) Harris, Jordan Lee; Balci, Yilmaz; Plant Science and Landscape Architecture (PSLA); Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    A survey of urban trees affected by bacterial leaf scorch caused by Xylella fastidiosa was conducted in the District of Columbia during 2012 and 2013. Disease occurred most frequently with Quercus palustris, Q. rubra, Ulmus americana, and Platanus occidentalis. Eight other symptomatic and five asymptomatic tree species were found infected. The bacterium was also detected on asymptomatic portion of seven tree species. The occurrence of crown dieback was found significantly associated with X. fastidiosa-infection on Q. palustris, Q. rubra, U. americana, and P. occidentalis. A multi-locus sequence typing analysis using 10 housekeeping loci for X. fastidiosa revealed five clonal strains among the urban trees. These strains were host specific, with only one clone being associated with members of the red oak family, American elm, American sycamore, and two clones being associated with mulberry. Long-term management strategies aimed at mitigating the occurrence of bacterial leaf scorch disease are discussed.