Transcriptome Analysis and Physiological Response to Salinity Stress in Adzuki Bean (Vigna angularis) at the Seedling...

Area of Science:

• Plant Science
• Molecular Biology
• Agricultural Science

Background:

• Adzuki bean (Vigna angularis) is a vital crop in China, used in traditional medicine and diets.
• Limited research exists on the molecular responses of adzuki beans to salinity stress using RNA-sequencing (RNA-seq).

Purpose of the Study:

• To investigate the molecular mechanisms underlying adzuki bean responses to salinity stress.
• To characterize salinity-induced physiological and transcriptomic alterations in the Jin Xiao Dou 6 (JXD6) cultivar.

Main Methods:

• JXD6 adzuki bean seedlings were treated with varying NaCl concentrations (0, 32.5, and 65.0 mmol/L).
• Physiological parameters including plant height, pigment content, leaf surface characteristics, reactive oxygen species (ROS) accumulation, and antioxidant enzyme activities were measured.
• Transcriptome profiles were analyzed using RNA-seq.

Main Results:

• Increasing NaCl concentrations inhibited plant height but increased leaf surface temperature, chlorophyll a, total chlorophyll, and carotenoid content.
• Salinity stress led to enhanced accumulation of hydrogen peroxide (H₂O₂) and superoxide anion radical (O₂⁻), along with increased activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT).
• RNA-seq identified 363 and 858 differentially expressed genes at 32.5 and 65.0 mmol/L NaCl, respectively. Upregulated genes were enriched in the spliceosome pathway, while downregulated genes were associated with plant hormone signal transduction, plant-pathogen interaction, and MAPK signaling pathways.

Conclusions:

• Adzuki beans exhibit complex physiological and molecular responses to salinity stress.
• Transcriptomic analysis reveals key pathways involved in adzuki bean salt tolerance, offering insights for crop improvement.