Speakers - 2026

Title: Sucrose-induced modulation of ethylene-responsive genes and miRNAs associated with vase life in carnation

Abstract

Carnation (Dianthus caryophyllus L.) exhibits significant variation in the expression of ethylene-responsive genes when subjected to different vase solutions. The present study aimed to evaluate the influence of sucrose on post-harvest physiological parameters particularly vase life, along with the transcriptional and post-transcriptional regulation of ethylene-responsive genes. The carnation cultivar Kloe was maintained in a 2% sucrose solution and compared with flowers placed in distilled water as control. A total of seven ethylene-responsive genes and four miRNAs were analysed to determine their relative expression levels in sucrose-treated and untreated flowers. The results indicated that ACO and WRKY-75 exhibited the highest expression levels, with Ct values ranging from 18 to 22, suggesting strong transcriptional activity. However, transcripts of ACO-1, ACS-1, SAG-29, SAG-12 and miR-004 were markedly downregulated, with log fold changes ranging from −1.35 to −3.58, indicating suppression of ethylene-related gene expression under sucrose treatment. In contrast, miR-001 and miR-002 showed significant upregulation in sucrose-treated samples. Meanwhile, WRKY-75, EIL-4, EIL-3-1 and miR-003 did not show notable changes in expression. Among the analysed genes, ACO-1, an important enzyme involved in ethylene biosynthesis, showed the highest level of downregulation (−3.58 log fold change). These findings suggest that sucrose may initiate signaling mechanisms that suppress ethylene biosynthesis and response pathways, thereby delaying senescence and extending the vase life of carnation flowers. The study also highlights the potential role of miRNA-mediated regulation of ethylene biosynthesis genes which could be explored further to enhance post-harvest longevity in ornamental crops.