Plant growth and development are greatly affected by the environment. Many genes have been identified to be involved in regulating plant development and adaption of abiotic stress. Apart from protein-coding genes, more and more evidence indicates that non-coding RNAs (ncRNAs), including small RNAs and long ncRNAs (lncRNAs), can target plant developmental and stress-responsive mRNAs, regulatory genes, DNA regulatory regions, and proteins to regulate the transcription of various genes at the transcriptional, posttranscriptional, and epigenetic level. Currently, the molecular regulatory mechanisms of sRNAs and lncRNAs controlling plant development and abiotic response are being deeply explored. In this review, we summarize the recent research progress of small RNAs and lncRNAs in plants, focusing on the signal factors, expression characters, targets functions, and interplay network of ncRNAs and their targets in plant development and abiotic stress responses. The complex molecular regulatory pathways among small RNAs, lncRNAs, and targets in plants are also discussed. Understanding molecular mechanisms and functional implications of ncRNAs in various abiotic stress responses and development will benefit us in regard to the use of ncRNAs as potential character-determining factors in molecular plant breeding.

MicroRNAs (miRNAs) belong to non-coding small RNAs which have been shown to take a regulatory function at the posttranscriptional level in plant growth development and response to abiotic stress. Hemerocallis fulva is an herbaceous perennial plant with fleshy roots, wide distribution, and strong adaptability. However, salt stress is one of the most serious abiotic stresses to limit the growth and production of Hemerocallis fulva. To identify the miRNAs and their targets involved in the salt stress resistance, the salt-tolerant H. fulva with and without NaCl treatment were used as materials, and the expression differences of miRNAs–mRNAs related to salt-tolerance were explored and the cleavage sites between miRNAs and targets were also identified by using degradome sequencing technology. In this study, twenty and three significantly differential expression miRNAs (p-value < 0.05) were identified in the roots and leaves of H. fulva separately. Additionally, 12,691 and 1538 differentially expressed genes (DEGs) were also obtained, respectively, in roots and leaves. Moreover, 222 target genes of 61 family miRNAs were validated by degradome sequencing. Among the DE miRNAs, 29 pairs of miRNA targets displayed negatively correlated expression profiles. The qRT-PCR results also showed that the trends of miRNA and DEG expression were consistent with those of RNA-seq. A gene ontology (GO) enrichment analysis of these targets revealed that the calcium ion pathway, oxidative defense response, microtubule cytoskeleton organization, and DNA binding transcription factor responded to NaCl stress. Five miRNAs, miR156, miR160, miR393, miR166, and miR396, and several hub genes, squamosa promoter-binding-like protein (SPL), auxin response factor 12 (ARF), transport inhibitor response 1-like protein (TIR1), calmodulin-like proteins (CML), and growth-regulating factor 4 (GRF4), might play central roles in the regulation of NaCl-responsive genes. These results indicate that non-coding small RNAs and their target genes that are related to phytohormone signaling, Ca²⁺ signaling, and oxidative defense signaling pathways are involved in H. fulva’s response to NaCl stress.

Rosa rugosa is a multifunctional species with various applications in fragrance extraction and ornamental, medical, and edible purposes. Compared to other species of Rosa, R. rugosa exhibits greater resistance to salt stresses; however, the mechanisms underlying its salinity tolerance are still unclear. Thus, we assessed the salt tolerance of 16 R. rugosa germplasms based on the changes in morphology and physiology under different salt concentrations. Among them, two cultivars ('Zizhi' and 'Fenzizhi') were chosen for transcriptome sequencing. The differentially expressed genes (DEGs) associated with phytohormone synthesis and signalling pathways, ROS production, carbohydrate metabolism and transport, stress response and resistance were identified as responding to salt stress in R. rugosa. PPI network analysis further identified two DEGs, SCL28 and E2F1, which exhibited the most interactions with other DEGs. Consequently, this research contributes to a greater understanding of salinity tolerance mechanism in R. rugosa and could provide gene resources for breeding salt-tolerant cultivars in Rosa.

Anthocyanins, which accumulate in fruits, flowers, and vegetative organs, play a critical role in plant reproduction, disease resistance, stress tolerance, and promoting human health. Although light significantly influences the development of various fruit pigments, the specific mechanisms through which it regulates anthocyanin accumulation during fruit ripening are not yet fully understood. This study aimed to investigate the role of light in anthocyanin biosynthesis using Aft tomato fruits, which accumulate pigments in the epidermis. To explore the effects of light on anthocyanin biosynthesis, half of each fruit was covered with aluminum foil to establish light-exposed and bagged conditions for comparative analysis. The results showed that the bagged treatment led to a significant decrease in the total anthocyanin content of the fruits. Transcriptome analysis revealed a notable upregulation of several structural genes involved in the anthocyanin biosynthetic pathway, specifically Sl4CL, SlCHS, SlCHI, SlF3H, SlDFR, and Sl3GT in the light-exposed fruits. Additionally, the expression levels of light-responsive genes and transcription factors, such as SlCRY1, SlSPA, SlUVR3, SlHY5, SlBBX24, SlMYB11, MADS-box transcription factor 23, SlHD-ZIP I/II, SlAN2-like, SlbHLH and SlWD40 proteins, were significantly higher in the light-exposed samples compared to those subjected to the bagged treatment. Weighted Gene Co-Expression Network Analysis (WGCNA) demonstrated a strong association between light-induced gene expression such as SlPAL, SlCHS1, SlDFR, SlF3H, SlF3′5′H, SlANS, SlHY5, and SlAN2-like quantified by qRT-PCR analysis and anthocyanin biosynthesis. Moreover, as the fruit matured, both anthocyanin accumulation and the expression of genes related to its biosynthetic pathway increased. These findings contribute to a foundational understanding of the regulatory network that influences light-induced processes and fruit development impacting anthocyanin accumulation, which will facilitate in-depth study of the functions of these identified genes and provide a foundation for breeding anthocyanin-rich tomato varieties.