Comparative transcriptomics and bioinformatics profiling provide insights into resistance to Fusarium wilt in melon

Abstract Melon is an important cash crop grown worldwide, with China leading the world in melon acreage. Melon wilt is becoming more common as the area under melon cultivation gradually increases. Therefore, it is crucial to understand the resistance pattern of Fusarium wilt in melons. In this work, among the four test melon cultivars, YG was highly resistant to Fusarium wilt and 1455 was disease‐resistant. However, 5657 was susceptible, while 5455 was highly susceptible to the disease. We detected 71,852 differentially expressed genes in 16 combinations, including 37,382 with up‐regulation and 3470 with down‐regulation, and we investigated 11 genes associated with resistance to Fusarium wilt through bioinformatics and transcriptome analysis. We identified two differentially expressed cinnamyl alcohol dehydrogenases ( CAD ) that were down‐regulated in the susceptible melon material in contrast to the resistant variety. Nine chitinase ( CHT ) genes were differentially expressed, with four showing up‐regulation and four showing down‐regulation in the susceptible compared to the resistant melon material. The MeloCHT genes were located on chromosomes 2, 6, 8, 11 and 12, with four of them on chromosome 8. MeloCAD1 was located on chromosome 1 and MeloCAD2 on chromosome 8. The physicochemical properties of the encoded proteins were predicted by bioinformatics, including theoretical isoelectric point, instability coefficient, relative molecular mass, lipid solubility index and hydrophilicity index. The genes encode proteins with α‐helix, extended strand, random coils and β‐turns. This study provides fundamental knowledge on the transcriptome of melons and establishes a foundation for future research on the detection and application of Fusarium wilt‐resistant genes in melons.