Microbiota transplantation for cotton leaf curl disease suppression-core microbiome and transcriptome dynamics

Area of Science:

• Agricultural Science
• Plant Pathology
• Microbiology

Background:

• Cotton Leaf Curl Disease (CLCuD) poses a significant threat to cotton production, particularly in susceptible Gossypium hirsutum varieties.
• Gossypium hirsutum exhibits high susceptibility to biotic stresses, necessitating novel disease management strategies.
• Microbiota transplantation is an emerging approach for enhancing plant disease resistance.

Purpose of the Study:

• To investigate the efficacy of microbiota transplantation in conferring resistance to Cotton Leaf Curl Disease (CLCuD) in Gossypium hirsutum.
• To identify specific microbial communities and genetic mechanisms associated with CLCuD resistance.
• To compare the effectiveness of rhizospheric versus phyllospheric microbiota transplantation.

Main Methods:

• Metabarcoding analysis of V3-V4 16S rRNA gene amplicon to characterize rhizosphere and phyllosphere microbiota.
• Interspecies and intraspecies microbiota transplantation experiments.
• Cotton Leaf Curl Disease (CLCuD) incidence assays and exogenous salicylic acid application as a control.
• Differential gene expression analysis (DESeq2) and functional pathway analysis.
• Transcriptomic analysis to identify host gene responses.

Main Results:

• Rhizospheric microbiota transplantation from CLCuD-resistant Gossypium arboreum significantly suppressed CLCuD incidence in susceptible G. hirsutum, surpassing salicylic acid treatment.
• Phyllospheric microbiota transplants also reduced disease incidence, though to a lesser extent than rhizospheric transplants.
• Key bacterial genera, including Pseudoxanthomonas and Stenotrophomonas, were identified in the rhizosphere of resistant G. arboreum and correlated with CLCuD suppression.
• Upregulation of stress response and metabolic pathways was observed in tolerant species and in G. hirsutum following rhizospheric microbiota transplantation.
• Transcriptomic data revealed enhanced expression of genes involved in protein phosphorylation and stress response.

Conclusions:

• Microbiota transplantation, particularly from the rhizosphere, is a potent and sustainable strategy for managing Cotton Leaf Curl Disease (CLCuD).
• Specific bacterial taxa and their associated functional pathways in the rhizosphere play a crucial role in conferring CLCuD resistance.
• Understanding the interplay between host genetics, microbial communities, and disease resistance mechanisms can lead to improved crop management practices.