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ARS Home » Pacific West Area » Parlier, California » San Joaquin Valley Agricultural Sciences Center » Crop Diseases, Pests and Genetics Research » Research » Publications at this Location » Publication #402312
Research Project: Development of Applied Management Systems for Diseases of Perennial Crops with Emphasis on Vector-Borne Pathogens of Grapevine and Citrus

Location: Crop Diseases, Pests and Genetics Research

Title: Enhancing PCR detection of Xylella taiwanensis using whole genome sequence information

Author
item SU, CHIOI-CHU - Taiwan Agricultural Chemicals And Toxic Substances Research Institute
item FUNG, JIE-AN - Taiwan Agricultural Chemicals And Toxic Substances Research Institute
item CHANG, RUEY-JANG - Taiwan Agricultural Chemicals And Toxic Substances Research Institute
item CHANG, CHUNG-JAN - University Of Georgia
item JAN, FUH-JYH - National Chung-Hsing University
item SHIH, HSIEN-TZUNG - Taiwan Agricultural Chemicals And Toxic Substances Research Institute
item Chen, Jianchi

Submitted to: International Congress of Plant Pathology Abstracts and Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 5/26/2023
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Xylella taiwanensis (Xt) is a nutritionally fastidious bacterial pathogen causing pear leaf scorch disease (PLSD) in Taiwan. Xt detection plays a key role in PLSD management. Multiple PCR systems based on single- or two-copy genes have been developed for Xt diagnosis. Xt detection could be further improved utilizing multi-copy genes. A total of 32 Xt whole genome sequences are now available in the GenBank, providing a sound resource for the development of robust PCR detection systems. By self-aligning the genome sequences of Xt Type strain PLS229, seven 714-bp sequences with similarity > 97% each other were identified. The sequences were annotated as part of the hemagglutinin-like protein gene. Based on this sequence, two primer sets, Xt7cp-378-F/R and Xt7cp-573-F/R, were designed. In silico experiment using GenBank database showed the high Xf-specificity of the two primer sets. SYBR green qPCR experiments using pure culture DNA from strains of Xt, X. fastidiosa and Xanthomonas campestris and PLSD plant DNA samples collected in Taiwan further confirmed the Xt-specificity. To evaluate PCR detection sensitivity, five previously developed Xt-specific primer sets, two from single-copy locus and three from two-copy locus, were simultaneously compared with Xt7cp-378-F/R and Xt7cp-573-F/R against the same set of PLSD samples. A reduction of 1-3 Ct values from the two 7-copy gene-based PCR systems were observed. Further evaluation of the two PCR systems is underway.