Transcriptomic and metabolomic analysis of allelopathic responses in Elymus nutans

Area of Science:

• Plant Biology
• Ecology
• Biochemistry

Background:

• Allelopathy, the chemical interaction between plants, significantly impacts plant community structure and function.
• Elymus nutans and Ligularia sagitta are key species in alpine grassland ecosystems, with potential allelopathic interactions influencing their coexistence.

Purpose of the Study:

• To elucidate the molecular mechanisms of allelopathic interactions between Elymus nutans and Ligularia sagitta extracts.
• To identify key genes, metabolites, and pathways involved in the allelopathic response of Elymus nutans.

Main Methods:

• Seed germination tests were conducted using varying concentrations of Ligularia sagitta extracts on Elymus nutans.
• Integrated transcriptome and metabolome analyses were employed to investigate molecular responses.
• Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed.

Main Results:

• A sensitive concentration range (0.01-0.10 mg/mL) for allelopathic effects was identified, with germination energy (GE) being more sensitive than germination rate (GR).
• Transcriptome analysis revealed 5617 differentially expressed genes (DEGs), primarily involved in ribosome biogenesis and plant hormone signal transduction.
• Metabolome analysis identified 361 differential metabolites (DMs), with phenylpropanoid biosynthesis highlighted as a core pathway responding to allelopathic stress.

Conclusions:

• The phenylpropanoid biosynthesis pathway, involving genes like PAL and CAD, and metabolites such as p-Coumaric acid, is crucial in the allelopathic response of Elymus nutans.
• This study provides insights into the molecular basis of allelopathy in alpine grasslands, informing conservation and sustainable utilization strategies.