Multi-Omics Analyses Reveal Metabolic Regulatory Networks in Salinity and Drought Adaptation of Basil QF, a Chinese...

The Ocimum genus, valued for its culinary, medicinal, and aromatic uses, is often cultivated in regions affected by drought and salinity. This study investigates the adaptive responses of QingFeng (QF), a newly identified basil cultivar locally known as vegetable "jingjie" in China, to high salinity and drought stress. DNA barcoding, mucilaginous seed analysis, flow cytometry, and karyotyping confirmed QF's identity, revealing a chromosome number of 2n = 76 and a 1C genome size of 2962 ± 36 Mb. Phenotyping, transcriptomic and metabolomic profiling, and hormone monitoring showed drought primarily suppressed leaf growth, while salinity inhibited root elongation. Notably, convergent and divergent responses to salinity and drought were observed, including stress-specific remodeling of core metabolic pathways such as the GS-GOGAT cycle, photorespiration, TCA cycle, and pyrimidine metabolism. Secondary metabolite profiling further demonstrated stress-specific patterns in the accumulation of flavonoids and alkaloids. These findings provide a theoretical foundation for deciphering abiotic stress adaptation mechanisms in basil and offering practical approaches to enhance local cultivation of the QingFeng cultivar.