Lycoris plants are known for their diverse flower colors, but the molecular mechanisms behind these variations remain unclear. In this study, we first used the CIELAB system to precisely measure flower color. We objectively defined the petals of Lycoris sprengeri as blue-purple (Bp) and compared them with the white petals of Lycoris longituba (W) and the red petals of Lycoris radiata var. pumila (R). Metabolomic analysis showed that specific kaempferol glycosides, including kaempferol-3-O-sophoroside and lonicerin, accumulated significantly in the blue-purple petals. Transcriptomic analysis revealed that genes related to flavonoid biosynthesis were generally more active in the colored petals (Bp and R). However, different expression patterns of key hydroxylase genes created a metabolic split. Specifically, the blue-purple petals showed high expression of LrF3′5′H (directing synthesis toward delphinidin) and LrFLS (promoting kaempferol accumulation), whereas the red petals mainly expressed LrF3′H (leading to cyanidin synthesis). Further investigation identified LrWRKY70 as a core transcription factor highly correlated with these flavonoid pathway genes. Crucially, we discovered a new long non-coding RNA, LncRNA401, located downstream of the LrWRKY70 antisense strand. It showed a strong positive correlation with LrWRKY70. Functional verification through transient overexpression demonstrated that LncRNA401 significantly increased the expression of LrWRKY70. This, in turn, broadly activated downstream flavonoid biosynthesis genes, including LrCHS, LrF3′5′H, LrFLS, and LrDFR. This cascade ultimately promoted the synthesis of anthocyanins and kaempferol derivatives, resulting in the unique blue-purple phenotype. Our results reveal a novel LncRNA401-LrWRKY70 regulatory module. This module plays a key role in metabolic reprogramming for flower color formation in Lycoris, providing important insights into plant secondary metabolism and valuable targets for breeding specific flower colors.

Rapid climate shifts in high-latitude regions profoundly impact the geographical distribution boundaries and molecular adaptive strategies of cold-tolerant plants. Lonicera caerulea, known for its excellent cold tolerance, provides an ideal model for exploring the molecular mechanisms of climate adaptation and trait formation. To elucidate the ecological and molecular mechanisms of climate adaptation in L. caerulea, we integrated species distribution modeling with multi-tissue transcriptome profiling. Distribution modeling identified temperature and precipitation as primary constraints on its current range, with projections suggesting a significant poleward expansion under future warming scenarios. At the molecular level, we identified 19 LcSWEET genes exhibiting functional differentiation. Rather than listing specific candidates, our findings highlight that certain LcSWEET members are transcriptionally activated during fruit maturation, while others are significantly upregulated in response to cold stress, underscoring their dual roles in plant reproduction and ecological adaptation. This study revealed that the LcSWEET gene family exhibits functional diversification in tissue-specific expression and low-temperature stress response. It provides molecular candidates that may inform future studies on plant adaptive response under climate change and lays a theoretical foundation for germplasm conservation and high-quality breeding of L. caerulea.

To investigate the effect of sorbitol feeding on immune responses and its underlying mechanism, this study employed crabapple (Malus micromalus), a species native to China, as the experimental material. Detached leaves were subjected to sorbitol feeding experiments, with water feeding as the control. The dynamic changes in lesion area and cell membrane permeability were measured across four groups of leaves following feeding and fungal inoculation, and transcriptome sequencing was performed on these four groups. The results revealed that compared to the control group, leaves fed with sorbitol prior to inoculation exhibited significantly reduced lesion areas and decreased cell membrane permeability. Transcriptome and KEGG pathway analyses indicated that differentially expressed genes were significantly enriched in the phenylpropanoid biosynthesis pathway. HPLC results demonstrated that quercetin and isorhamnetin contents increased significantly after sorbitol feeding, and both compounds were shown to inhibit the mycelial growth of Alternaria alternata, thereby enhancing the disease resistance of crabapple leaves. Among the associated genes, MmF3H1, which regulates the synthesis of quercetin and isorhamnetin, showed the highest level of enrichment. Co-expression trend analysis and qPCR results revealed that MmNAC17 and MmbZIP1 exhibited strong co-expression relationships with MmF3H1 and responded to sorbitol regulation. Functional validation was conducted by constructing overexpression and silencing vectors for MmNAC17/MmbZIP1 and performing transient transformation, thereby elucidating the molecular and biochemical mechanisms underlying the response of M. micromalus to A. alternata. This study provides a theoretical reference for breeding crabapple varieties with enhanced resistance to leaf spot disease.