![xf and infection in plant xf and infection in plant](https://www.mdpi.com/pathogens/pathogens-10-01093/article_deploy/html/images/pathogens-10-01093-g001.png)
We developed a protocol for a non-destructive collection of chemicals released from grapevines following Xf inoculation and/or salicylic acid spray which mimics the wounding response. The goal of this research project is to focus on understanding the natural defense mechanisms of grape plants in support of Objective 2 of the in-house project to determine the nature and mechanism(s) of susceptibility/resistance to Xf infection in Vitis species and Prunus species. The research will focus on terpene synthases and acyl transferases, as well as two methyl transferases salicylic acid methyl transferase (SAMT) and jasmonic acid methyl transferase (JAMT), which are critical components of plant defense pathways.
![xf and infection in plant xf and infection in plant](https://media.springernature.com/lw685/springer-static/image/art%3A10.1038%2Fs41598-020-80090-x/MediaObjects/41598_2020_80090_Fig4_HTML.png)
![xf and infection in plant xf and infection in plant](https://c8.alamy.com/comp/2BATEXF/dying-rubber-plant-in-a-corona-ice-bucket-in-stockbridge-edinburgh-scotland-uk-2BATEXF.jpg)
Approach (from AD-416) Use functional genomic information, transcriptomics, bioinformatics, metabolomics, and high-throughput biochemistry approaches to determine the functions of the components in grapevines associated to the defense against biotic stress especially Xylella fastidiosa. Research will focus on secondary metabolites that are vital in plant defense against various pathogens and pests. Progress 10/01/09 to 09/30/10 Outputs Progress Report Objectives (from AD-416) Identify the mechanisms of the biosynthesis of metabolites in grape plants involved in defense pathways on grape responses to Xylella fastidiosa. Researchers cooperatively planned and conducted the research, and communicated regularly via site visits and through email and telephone on a weekly basis. Research progresses was presented in several academic and industrial meetings. These results advance understanding of molecular mechanism(s) in grapes resistant to abiotic and biotic stress, including Xf infection. Overall, an integrated genomics approach combining metabolomics, bioinformatics and biochemical assays were developed to facilitate identification of candidate plant host defense genes from grapes. The analysis focused on two types of genes: the Salicylic Acid Methyltransferase, Benzoiz Acis Methyltransferase, and Theobromine methyltransferase (SABATH) and the methylesterase involved in the metabolism of methylesters. Based on the identified volatiles released from grape plants, a working hypothesis was generated in which genes and enzymes from Pierce's disease- resistant grapes control production of grape defense metabolites. Bioinformatic analysis of the grape genome sequence identified candidate genes responsible for biosynthesis of plant host defense metabolites. Metabolites associated with the defense response in grapes were identified. Upon treatment with salicylic acid, grape plants produced significantly higher amounts of toxic secondary metabolites than untreated control plants. The collected chemicals were then identified by Gas Chromatography-Mass Spectrometry. In this method, grape plants are placed in a closed glass container and chemicals released from the plant are collected using a non-destructive headspace technique.
![xf and infection in plant xf and infection in plant](https://media.springernature.com/lw685/springer-static/image/art%3A10.1038%2Fs41598-020-80090-x/MediaObjects/41598_2020_80090_Fig2_HTML.png)
A method for collection and identification of grape metabolites potentially involved in host plant resistance to Xylella fastidiosa (Xf) was established. The objectives of this project are to identify and characterize metabolites associated with the natural defense mechanisms of grapevines. This Specific Cooperative Agreement supports Objective 3.A of the parent project. Progress 04/17/06 to 02/27/11 Outputs Progress Report Objectives (from AD-416) Identify the mechanisms of the biosynthesis of metabolites in grape plants involved in defense pathways on grape responses to Xylella fastidiosa.