PubMed · 2026-02-17
When tomatoes ripen, they become tastier and more nutritious — but also far more vulnerable to mold and fungal rot. Scientists have mapped the hormonal and genetic systems behind this trade-off, pointing toward ways to keep tomatoes disease-resistant longer without sacrificing flavor or nutrition.
Ethylene is the master hormone driving tomato ripening, but it interacts with at least five other hormones (including jasmonic acid and salicylic acid) that also regulate disease defense, making ripening and immunity inseparable.
Three key transcription factors — MADS-RIN, NAC-NOR, and SBP-CNR — simultaneously control ripening progression and increase susceptibility to necrotrophic fungi such as Botrytis cinerea.
Epigenetic mechanisms including DNA methylation, histone modifications, and non-coding RNAs act as additional layers of control that link ripening timing to immune response, offering new targets for crop improvement without direct gene editing.
