Gene Expression in Carnation Cells Induced by Fusarium oxysporum f.sp. dianthi

Background and Objective: Carnations (Dianthus caryophyllus) are a major export in global floriculture, but their production is threatened by fusariosis, caused by Fusarium oxysporum f.sp. dianthi (FOX), a pathogen responsible for vascular wilt and significant yield losses. This study aimed to investigate the gene expression patterns in carnation cells in response to FOX infection. Materials and Methods: Carnation varieties with known susceptibility or resistance to FOX were selected. Leaf explants were cultured in vitro on MS media with 2,4-D to produce undifferentiated cells. Elicitation was performed by exposing these cells to FOX conidia. The mRNA was extracted using the Trizol^® method and purified with the NucleoSpin mRNA^® kit. De novo transcriptome sequencing was carried out using the TruSeq Stranded mRNA LT Sample Prep Kit and the NovoSeq 6000 S4 Reagent Kit by Macrogen (Korea). Unigenes were identified using the CD-HIT-EST program, annotated against public databases, and analyzed for predicted Open Reading Frames (ORFs). Results: A total of 85,669 unigenes were identified, of which 32,101 (37.4%) were successfully annotated. Differential expression analysis revealed significant variations in gene expression between elicited and non-elicited cells in resistant and susceptible varieties. Key genes such as Phenylalanine ammonia-lyase, Anthocyanin 5-O-glucosyltransferase, Beta-1,3-glucanase, and Chitinase 4-like glycosyl hydrolase showed altered expression, along with 24 other genes potentially involved in plant defense mechanisms. Conclusion: The findings indicate that FOX infection induces a multigene, multivariate response in carnation cells. Gene expression patterns differ significantly between resistant and susceptible varieties, highlighting the complex genetic basis of resistance. These insights can contribute to more efficient breeding strategies for developing FOX-resistant carnation cultivars.