Date of Defense
3-6-2025 10:00 AM
Location
E1, 1027
Document Type
Dissertation Defense
Degree Name
Master of Science in Molecular Biology and Biotechnology
College
College of Science
Department
Biology
First Advisor
Prof. Synan AbuQamar
Keywords
Date palm, Fusarium, Genomics, Plant defense response, Sudden decline syndrome, Transcriptomics
Abstract
Sudden decline syndrome (SDS) poses a significant threat to the date palm (Phoenix dactylifera), a crop of critical agricultural and cultural importance in arid regions. Despite its growing impact, the molecular basis of the host-pathogen interactions driving this disease remains poorly understood. This dissertation investigates the disease dynamics of SDS, a severe affliction of date palm caused by the fungal pathogen Fusarium proliferatum DSM 106835 (Fp). The objective of this study is to elucidate the molecular mechanisms underlying Fp infection in date palm and characterize the plant defense responses. To achieve this, whole-genome sequencing (WGS) of the novel Fp strain was integrated with time-series transcriptomics to monitor disease progression in both leaf and root tissues of infected date palms. A high-resolution, chromatin-organized reference genome was generated for Fp, comprising 15,580 predicted genes and 16,321 transcripts. Among these, 6,459 genes were identified as potentially involved in host-pathogen interactions, including a substantial number of plant avirulence determinants associated with disease development and suppression of host immunity. Transcriptomic profiling of infected date palm tissues revealed that Fp triggers both pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) and effector-triggered immunity (ETI), possibly interfering with mitogen-activated protein kinase (MAPK) signaling and weakening host resistance mechanisms. Infected seedlings exhibited hallmark defense responses such as cell wall remodeling, reactive oxygen species (ROS) production, disrupted photosynthetic activity, and a coordinated hormone-mediated defense strategy. In addition, Fp infection induced significant alterations in energy metabolism, including carbohydrate, amino acid, and lipid pathways, alongside modulation of primary and secondary metabolite biosynthesis and defense-related enzymatic activities. This integrated omics approach offers novel insights into the molecular strategies employed by Fp during infection and the corresponding defense responses of date palm. These findings highlight key molecular pathways that could be targeted to enhance disease resistance in this economically and culturally important crop.
Included in
UNRAVELLING HOST DEFENSE AND PATHOGEN VIRULENCE IN FUSARIUM PROLIFERATUM-INDUCED SUDDEN DECLINE SYNDROME OF DATE PALM IN THE UAE
E1, 1027
Sudden decline syndrome (SDS) poses a significant threat to the date palm (Phoenix dactylifera), a crop of critical agricultural and cultural importance in arid regions. Despite its growing impact, the molecular basis of the host-pathogen interactions driving this disease remains poorly understood. This dissertation investigates the disease dynamics of SDS, a severe affliction of date palm caused by the fungal pathogen Fusarium proliferatum DSM 106835 (Fp). The objective of this study is to elucidate the molecular mechanisms underlying Fp infection in date palm and characterize the plant defense responses. To achieve this, whole-genome sequencing (WGS) of the novel Fp strain was integrated with time-series transcriptomics to monitor disease progression in both leaf and root tissues of infected date palms. A high-resolution, chromatin-organized reference genome was generated for Fp, comprising 15,580 predicted genes and 16,321 transcripts. Among these, 6,459 genes were identified as potentially involved in host-pathogen interactions, including a substantial number of plant avirulence determinants associated with disease development and suppression of host immunity. Transcriptomic profiling of infected date palm tissues revealed that Fp triggers both pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) and effector-triggered immunity (ETI), possibly interfering with mitogen-activated protein kinase (MAPK) signaling and weakening host resistance mechanisms. Infected seedlings exhibited hallmark defense responses such as cell wall remodeling, reactive oxygen species (ROS) production, disrupted photosynthetic activity, and a coordinated hormone-mediated defense strategy. In addition, Fp infection induced significant alterations in energy metabolism, including carbohydrate, amino acid, and lipid pathways, alongside modulation of primary and secondary metabolite biosynthesis and defense-related enzymatic activities. This integrated omics approach offers novel insights into the molecular strategies employed by Fp during infection and the corresponding defense responses of date palm. These findings highlight key molecular pathways that could be targeted to enhance disease resistance in this economically and culturally important crop.