Effect of Silencing CaLEA-Dc3 Gene on Salt Tolerance in Capsicum annuum L.

Aims Pepper ( Capsicum annuum L.) is a widely cultivated vegetable crop. However, soil salinization and alkalization have increasingly threatened its healthy growth. Exploring key genes and molecular mechanisms underlying salt tolerance in pepper is crucial for the sustainable development of pepper industry. In this study, transcriptome sequencing analysis of pepper plants under salt stress revealed that CaLEA-Dc3 (CA03g31580) gene was highly upregulated, suggesting its potential role in salt stress response. Methods Using virus-induced gene silencing (VIGS) technology, CaLEA-Dc3 gene was silenced and the related physiological indicators were measured. Compared with control plants, the expression of CaLEA-Dc3 gene was disappeared in silenced plants, accompanied by decreased activities of superoxide dismutase (SOD) and peroxidase (POD), and increased catalase (CAT) activity and malondialdehyde (MDA) content. Additionally, proline content decreased, root activity declined, chlorophyll content decreased, and root system shrank. After NBT and DAB staining, reactive oxygen species (ROS) damage in the leaves of silenced plants intensified. Results These results indicated that CaLEA-Dc3 gene was involved in salt stress response. Silencing CaLEA-Dc3 gene reduced salt tolerance of pepper plants. Conclusions Our findings provided a theoretical basis for breeding salt-tolerant pepper varieties.