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Aroma is an important factor that guides consumers in purchasing and is thus very important in melon research. To our knowledge, the number of studies with a focus on the aroma differences of the same melon variety in different production areas is largely limited. In this study, the differences in aroma components of "Nasmi" melons from two different production regions were analyzed using gas-phase ion migration spectroscopy. Transcriptome sequencing was performed for analyzing fragrance-related genes. Results showed that there were significant differences in the aroma components between products from the two regions. The total amount of aroma compounds from the Turpan region (TT) was 1.7 times higher than that from the Altay region (AT). Through the analysis of transcriptome data, the key genes encoding melon aroma components in different regions were identified as ethanol dehydrogenase, 3-hydroxyl-coenzyme A (CoA) dehydrogenase, acyl-CoA oxidase, long-chain acyl-CoA synthetase, acetaldehyde dehydrogenase, and acetyl-CoA acyltransferase. Real-time quantitative polymerase chain reaction (RT-qPCR) showed that the verified genes were similar to the transcriptome. In this study, the main aroma components of the same variety of melon that differed in different production areas and the key genes causing these differences were identified. In addition, the aroma metabolic pathway of melon in different regions was preliminarily elucidated. These results could provide a theoretical basis for further study of the formation mechanism of melon aroma and breeding.

This study investigated how salicylic acid (SA) mediates the response of melon (Cucumis melo) seeds to salt stress using physiological and transcriptomic methods. The effects of SA on the antioxidant enzymes, osmoregulatory substances, and transcriptome of melon seeds under salt stress were investigated using sodium chloride (NaCl, 100 mmol·L−1) as the stress stimulant and SA + NaCl (0.25 mmol·L−1 + 100 mmol·L−1) as the alleviation treatment. The results showed that SA positively influences salt tolerance by increasing the activity of superoxide dismutase activity (SOD) and catalase activity (CAT) while decreasing proline content (Pro). Differentially expressed genes (DEGs) were identified by transcriptome data analysis, of which 2958 were up-regulated, and 2157 were down-regulated. These genes were mainly involved in the mitogen-activated protein kinase (MAPK) signaling pathway and plant hormone signal transduction, lipid metabolism (linoleic and α-linolenic fatty acid metabolism), biosynthesis of secondary metabolites (phenylpropanoid pathway and flavonoid biosynthesis), and related pathways. Further analysis revealed that SA might alleviate salt stress by initiating a series of signaling pathways under salt stress, participating in lignin biosynthesis to improve cell wall stability, and positively regulating lipoxygenase (LOX) genes. These results provide valuable information and new strategies for future salt resistance cultivation and high melon yield.