Interaction Between Climatic Variation and Pathogen Diversity Shape Endemic Disease Dynamics in the Agricultural...

Area of Science:

• Plant Pathology
• Agricultural Microbiology
• Ecology

Background:

• Recurring outbreaks of endemic pathogens pose significant threats to agriculture.
• Variability in bacterial disease epidemics and their drivers remain poorly understood.

Purpose of the Study:

• To investigate the factors influencing bacterial disease epidemics in the Xanthomonas-tomato pathosystem.
• To link pathogen diversity and climatic conditions to disease severity and strain dynamics.

Main Methods:

• Utilized strain-resolved metagenomics to quantify local pathogen diversity within fields.
• Employed response-specific regression models to analyze environmental variables.
• Tracked single-nucleotide polymorphism (SNP) variants and allelic frequencies.

Main Results:

• Pathogen heterogeneity with multiple co-occurring lineages is common, with higher diversity correlating with increased disease severity.
• Abrupt environmental changes significantly explained variability in disease severity.
• Two distinct pathogen lineages with climate-dependent strategies coexisted, and seasonal alleles fluctuated with climatic conditions.

Conclusions:

• Seasonal fluctuations in pathogen strain composition, diversity, and climate-influenced fitness are critical in shaping bacterial spot disease severity and variability.
• Understanding these dynamics is essential for predicting and managing agricultural disease outbreaks.
• Integrated approaches combining pathogen genomics and environmental data are crucial for agricultural disease management.