The nitrate signaling core regulator NLP7 is known to negatively regulate salt tolerance in Arabidopsis thaliana, but the function of the (SsNLP7A) gene in the halophyte Suaeda salsa remains unclear. To investigate whether SsNLP7A participates in salt stress responses, this study heterologously overexpressed the gene in tomato (Solanum lycopersicum) and systematically evaluated its function under salt stress through phenotypic, physiological, and transcriptomic analyses. The results indicate that SsNLP7A overexpression significantly promotes tomato root development and alleviates growth inhibition caused by salt stress. Under salt treatment, transgenic plants exhibited significantly higher chlorophyll content, accumulation of osmotic regulators (proline and soluble sugars), and antioxidant enzyme (POD, CAT, SOD) activity compared to wild-type plants. Transcriptome analysis further revealed that SsNLP7A enhances salt tolerance by regulating carbon metabolism, phytohormone signaling pathway, photosynthesis, and antioxidant pathways. Collectively, this study elucidates the positive regulatory role of SsNLP7A in salt stress response, providing new insights into its molecular mechanisms.

Plants are often subjected to drought stress, which can significantly inhibit their growth and development. Previous studies have found that the aldehyde dehydrogenase (ALDH) gene family plays an important role in plant stress adaptation by detoxifying reactive aldehydes and mitigating oxidative damage. In this study, 18 ALDH genes were identified and systematically analyzed from the telomere-to-telomere (T2T) genome of the desiccation-tolerant Syntrichia caninervis, an excellent tolerance moss to drought, cold and radiation. Phylogenetic analysis classified these ScALDHs into 11 subfamilies, demonstrating high conservation across plant lineages from bryophytes to angiosperms. Promoter region analysis revealed an abundance of stress-responsive cis-acting elements with ABRE and ARE motifs. Transcriptomic profiling demonstrated significant upregulation of key ScALDH genes under dehydration, rehydration, and ABA treatments, including ScALDH2B2, ScALDH7B4, ScALDH11A2, and ScALDH21A2. Weighted Gene Co-expression Network Analysis (WGCNA) further implicated these genes are involved in pathways related to drought response, oxidoreductase activity, and photosynthesis regulation. Heterologous expression of these canditate genes in Arabidopsis thaliana enhanced drought tolerance by improved root architecture, elevated ROS scavenging capacity. The study reveals the evolutionary conservation and functional diversity of ALDH genes in S.caninervis, providing a theoretical foundation for their application in stress-resistant crop breeding.

Hormones regulate fruit ripening and sugars accumulation, but the specific role of abscisic acid (ABA) in melon remains unclear. Here, we systematically investigated the sugars dynamics and the regulatory effects of ABA on melon fruit through the application of ABA and nordihydroguaiaretic acid (NDGA), an ABA biosynthesis inhibitor. Sugars profiling revealed a clear developmental transition, in which fructose and glucose were the primary sugars accumulated in melon during the early stages, while sucrose accumulated during the later stages. Moreover, enzyme activity assays indicated this transition resulted from changes in the activity of sucrose-metabolizing enzymes, from degradation to biosynthesis during fruit ripening. Furthermore, ABA treatment significantly promoted ethylene production, fruit ripening, and sugars accumulation, while NDGA treatment delayed these processes. Transcriptome analysis revealed that exogenous ABA induced the expression of genes related to endogenous ABA and ethylene synthesis as well as diverse genes related to sucrose metabolism and transport. Further analysis suggested that CmHB1 and CmHB5 may function as candidate regulators in the regulatory network, and their heterologous overexpression significantly accelerated fruit ripening and promoted sugars accumulation in transgenic tomato. Collectively, this study suggests an ABA-mediated regulatory module involved in sugars metabolism during melon ripening, providing potential molecular targets for improving melon quality through ABA pathway manipulation.

Galactinol synthase (GolS) is a key rate-limiting enzyme in the biosynthetic pathway of raffinose family oligosaccharides (RFOs), and plays a crucial role in plant responses to abiotic stresses such as low temperature. Saussurea involucrata, an alpine plant adapted to extreme habitats, serves as an ideal resource for mining unique and valuable stress-tolerance genes. In this study, we isolated and cloned the SiGolS3 gene from S. involucrata, and performed heterologous overexpression and functional verification in Broussonetia papyrifera. Physiological and biochemical analyses revealed that SiGolS3 exerts its cold-tolerant function by promoting RFO accumulation, which in turn maintains cellular osmotic homeostasis, alleviates reactive oxygen species damage, preserves plasma membrane integrity under low-temperature stress, and synergistically promotes cold-responsive gene expression, ultimately enhancing freezing tolerance in transgenic B. papyrifera. This study advances understanding of alpine plant adaptation to extreme environments and offers a candidate gene for improving stress tolerance in woody plants.

Melons undergo rapid softening after harvest, severely compromising their storage potential and commercial value. Gibberellic acid (GA) regulatory mechanisms in melon fruit ripening and cuticular wax biosynthesis are unclear. In this study, using "Bethekxin" melons, we used postharvest spray GA₃ and its biosynthesis inhibitor paclobutrazol (PAC), combined with physiological assays, microscopic observations, and molecular biology techniques, demonstrating that GA₃ treatment significantly delayed melon color conversion, softening, and overall quality deterioration. Further analysis revealed that GA increased the total wax content of melon peels, increasing cuticle thickness and thus helping to maintain peel firmness. This is because GA increased the content of alcohols and wax esters in the wax of melon peel and was associated with GA upregulating the transcription level of the wax biosynthesis gene CmFAR3. This study offers both theoretical insights and practical evidence to support the use of GA in postharvest melon preservation.

Circadian rhythms are critical for plants to adjust growth and development in response to a fluctuating environment. Here, we report the functional characterization of SiRVE8, a circadian gene insolated from Saussurea involucrata, a plant that thrives in extreme environments. Expression pattern analysis revealed that SiRVE8 exhibits distinct circadian rhythmicity and is induced by salt stress and cold stress (4 °C). Functional verification using transgenic Arabidopsis and tomato consistently show that SiRVE8 positively regulates salt tolerance by reducing oxidative damage. Transcriptome analysis of transgenic Arabidopsis futher demonstrated that overexpression of SiRVE8 alters the expression of numerous stress-responsive genes, among which a large number are ROS-scavenging genes. Mechanistically, We confirm that SiRVE8 functions as a transcription activator that directly binds to the promoter of AtERF109 and upregulates its expression. Collectively, this findings establishes a SiRVE8-AtERF109-ROS regulatory module, which mitigates salt-induced oxidative damage and enhancing salt tolerance. This study not only provides new insights into the molecular mechanism by which the circadian clock component SiRVE8 mediates plant salt stress responses but also identifies SiRVE8 as a key candidate gene for genetic improvement of crop salt tolerance in the future.

Improving cotton yield without sacrificing fiber quality remains a major breeding challenge. In this study, a carpel-specific RNA interference construct targeting GhCKX3b was introduced into the elite upland cotton cultivar ‘Yuanmian 8’, which has high fiber quality but relatively low lint percentage. We evaluated the effects of this construct on cytokinin accumulation, yield-related traits, and fiber quality across T0, T1, and T2 generations. Carpel-specific suppression of GhCKX3b increased cytokinin content in T2 positive lines by 50.3% to 102.0% relative to wild-type. Transgenic lines consistently showed increased lint percentage, boll weight, and seeds per boll, while seed index decreased moderately. In the best-performing line, lint percentage increased from 36.4% to 45.8%, and boll weight from 6.30 g to 7.31 g. Multi-year field evaluations confirmed stable inheritance of these improvements across generations. Importantly, major fiber quality parameters—including length, strength, and micronaire—remained within high-quality cotton standards. These results indicate that carpel-specific GhCKX3b suppression effectively improves key yield components in a high-quality cotton background without compromising fiber quality. This study provides breeding-oriented evidence supporting the application of tissue-specific cytokinin regulation in cotton improvement.

Melons are prone to softening and dehydration after harvest, rapidly deteriorating in commercial quality at room temperature, which creates a bottleneck for the industry. This study investigated the function and mechanism of action of chitin-inducible gibberellin-responsive 1 (CmCIGR1), a gene highly expressed in gibberellin-repressed fruit, during the post-harvest ripening phase of melons. The results showed that after melon was picked, over-expression of CmCIGR1 significantly promoted ethylene release, respiratory burst and cell wall degradation, especially accelerated fruit softening and color change under abscisic acid (ABA) treatment. Transient over-expression experiments demonstrated that both CBF cold-inducible element of expression 1 (CmICE1) and Protein phosphatase 2 C A1 (CmPP2CA1) inhibited pericarp color change and maintained the fruit firmness. Protein interaction experiments (yeast two-hybrid, BiFC, and LCI) confirmed that CmCIGR1 interacts with CmICE1 in the nucleus. Yeast one-hybrid assay and dual-luciferase reporter gene assay showed that CmICE1 could directly bind to the CmPP2CA1 promoter and activate the expression of CmPP2CA1. In summary, CmCIGR1 is transcriptionally repressed by gibberellin (GA) signaling, antagonizing the ABA negative feedback regulator CmICE1, thereby weakening the transcriptional repression of the core ABA signaling inhibitor CmPP2CA1, ultimately promoting ABA-mediated postharvest ripening of melon fruits. This study not only deepens our understanding of the mechanism by which GA and ABA interact to regulate postharvest fruit ripening but also provides a new molecular target for the development of targeted freshness-preservation technologies.

The plant-specific transcription factor GhPLATZ, a zinc finger protein, plays a crucial role in plant growth and stress response. This study achieved heterologous expression of the GhPLATZ01 and GhPLATZ15 genes from upland cotton in tomato plants, generating two transgenic lines: trans-GhPLATZ01 and trans-GhPLATZ15. Overexpression of these genes resulted in transgenic tomatoes with higher chlorophyll content, relative water content, and proline levels, while showing reduced malondialdehyde content and conductivity. These findings indicate that GhPLATZ01 and trans-GhPLATZ15 significantly minimize cell membrane damage and enhance plant stability under drought conditions. Additionally, overexpression of these genes upregulated antioxidant enzyme-related genes in tomatoes, leading to enhanced antioxidant activity and reduced oxidative stress. Consequently, this study demonstrates that GhPLATZ01 15 can improve drought resistance through improved water retention, reduced cellular damage, enhanced membrane stability, and antioxidant capacity, providing valuable genetic resources for developing drought-resistant crops.

Abstract Maintaining energy homeostasis is essential for preserving postharvest fruit quality. This study investigated the effects of near-freezing temperature (NFT; −1±0.5 °C) storage on respiratory and energy metabolism in prunes (Prunus domestica L.) compared with conventional low-temperature (LT; 4±0.5 °C) storage. Over 42 d, NFT-treated prunes exhibited significantly lower weight loss, firmer texture, and delayed color changes relative to LT samples. NFT suppressed respiration rate and ethylene production, reduced cell membrane permeability and malondialdehyde accumulation, and better preserved mitochondrial structure. At the metabolic level, NFT maintained higher adenosine triphosphate (ATP) and energy charge, enhanced nicotinamide adenine dinucleotide phosphate accumulation, and delayed the decline of nicotinamide adenine dinucleotide kinase activity. NFT downregulated hexokinase and phosphoglucose isomerase, conserving ATP and redirecting glucose-6-phosphate flux toward the pentose phosphate pathway, thereby promoting redox balance. The expression of pyruvate kinase was upregulated under NFT, facilitating pyruvate entry into the tricarboxylic acid cycle while suppressing pyruvate decarboxylase and alcohol dehydrogenase expression, thus limiting anaerobic fermentation. The activities of key mitochondrial enzymes, including succinate dehydrogenase, cytochrome c oxidase, and ATPase, were consistently higher under NFT, supporting efficient oxidative phosphorylation. NFT modulated respiratory and energy metabolism to maintain energy stability, delay senescence, and extend storage life in prunes. These findings highlight NFT as an effective strategy to preserve postharvest quality and provide mechanistic insights into temperature-mediated regulation of fruit metabolism.

High temperatures significantly impair the yield and quality of cotton. Ankyrin-repeat proteins (ANKs) are among the largest superfamilies of proteins in plants and play vital roles in both biotic and abiotic stress responses. In this study, we identified and characterized members of the cotton ankyrin repeat protein (ANK) gene family, focusing on the ANK-TM subfamily member GhANK169, which was highly upregulated in the RNA-seq data of cotton plants exposed to 42 °C. Overexpression of GhANK169 in tobacco at 42 °C resulted in improved phenotypic resilience, enhanced antioxidant enzyme activity, and reduced relative electrolyte leakage (REL) and malondialdehyde (MDA) content. Conversely, silencing GhANK169 in cotton via virus-induced gene silencing (VIGS) renders plants highly susceptible to heat stress, with symptoms including accelerated water loss, reduced relative water content (RWC), elevated superoxide anion (O2-) and hydrogen peroxide (H2O2) levels, and diminished reactive oxygen species (ROS) scavenging capacity. Transcriptome sequencing revealed that crucial genes associated with ABA signaling, ROS response, endoplasmic reticulum protein quality control, cytoskeleton maintenance, and substance transport were affected in the treated plants. This study enhances our understanding of the cotton ANK gene family and offers valuable genetic resources for improving cotton heat tolerance mechanisms and breeding strategies.

The rubber tree currently serves as the sole source of natural rubber (NR). However, its limited cultivation range and the increasing global NR demand necessitate the development of an alternative crop for NR production. This study reports that Lactuca serriola can produce high-quality NR suitable for industrial rubber demand. The rubber molecular weight of L. serriola exceeds 750 kg/mol, with NR production occurring throughout the entire plant. Furthermore, treatments with ethylene, methyl jasmonate (MeJA), and salicylic acid (SA) significantly increased rubber content in L. serriola. Transcriptome analysis revealed that ethylene and MeJA treatments affected gene expression associated with isopentenyl pyrophosphate (IPP) synthesis, while ethylene and SA treatments influenced gene expression involved in sucrose transportation and metabolism. Through Pearson correlation coefficient (PCC) analysis and virus-induced gene silencing, several transcription factors and LsCPTs/LsCPTL were identified as key regulators of rubber synthesis in L. serriola. Yeast two-hybrid and co-expression assays suggested that LsCPTL anchors LsCPT1 and LsCPT2 to the endoplasmic reticulum, forming a protein complex that regulates rubber synthesis. This study provides a preliminary analysis of the mechanism by which plant hormones regulate rubber synthesis in L. serriola, revealing its significant potential as an alternative to the rubber tree for NR production.

Cotton (Gossypium hirsutum) is the predominant global fiber crop and has considerable significance because of its agronomic characteristics. Among these characteristics, plant height plays a vital role in determining harvest index and yield potential. Previous studies have mainly focused on elucidating the mechanisms governing the ICE-CBF-COR cascade to enhance plant resilienceto low temperatures. Although the ICE2 lines did not show cold tolerance, they exhibited dwarfing of the plants and increased yield. This led to the observations of reduced hypocotyl and internode length, increased biomass, higher yield, and shorter fiber length in the ICE2 lines through phenotypic assessment. From the leaf transcriptome analysis, differential expression of the BR synthesis signaling pathway and the CBF1 gene was identified. qRT-PCR analysis revealed upregulation of GhCBF1 and downregulation of GhTCH4 in the stems of the ICE2 lines. Significantly, the application of BL spray led to an increase in cotton plant height, with the ICE2 lines demonstrating the highest elongation rate. In conclusion, the reduction in plant height observed in the ICE2 lines can be ascribed to the integration of the SiICE2 gene influencing the BR signaling pathway and the expression of the CBF1 gene in cotton, which inhibits cell elongation and results in shorter cotton plants. To provide a reference for the optimization of agricultural cotton production.

Cotton (Gossypium hirsutum), a key fiber crop, plays a vital role in the development of the agricultural and textile industries. Recognizing that photosynthesis contributes to approximately 95 % of crop yield, enhancing its efficiency is crucial for improving crop yield. One approach targets key regulatory enzymes, such as Fructose-1,6bisphosphate aldolase (FBA), which is known for its role in the Calvin cycle. After introducing the SiFBA4 gene from Saussurea involucrata into cotton, we investigated how this gene influences photosynthetic characteristics, agronomic traits, yield, and fiber quality, and elucidated the mechanisms using transcriptomic and metabolomic analyses. The analysis showed significant improvements in transgenic lines compared to the wild type. There was a 17.47 % increase in the net photosynthetic rate and a 19.22 % increase in seed cotton yield. We observed an increase in the number of fruit branches and bolls, although the fiber length and strength decreased. Metabolomic analysis revealed reduced sugar content in transgenic leaves and increased sugar content in roots. Transcriptomic analysis showed the upregulation of genes encoding Calvin cycle enzymes, the chloroplast electron transport chain (PSI, Cytb6/f, and PSII), chlorophyll synthesis, and sugar transporters. SiFBA4 enhanced photosynthetic efficiency by increasing Calvin cycle enzyme activity and light reaction-related gene expression. It improves photosynthetic product distribution by promoting sugar transporter gene expression and increasing yield. These findings demonstrate SiFBA4's role in regulating photosynthesis and yield formation, provide genetic resources for cotton breeding, and offer a basis for designing crop carbon assimilation and distribution networks.

Low-temperature stress severely limits plant growth and reduces agricultural productivity. Calmodulin-like (CML) proteins are crucial calcium sensors in plant cold responses. Transcriptome analysis of cold-stressed Saussurea involucrata identified seven differentially expressed CML genes. qRT-PCR confirmed that SiCML6 was strongly induced at 4 °C and −2 °C. Bioinformatics analysis showed that SiCML6 encodes a transmembrane protein containing an EF-hand domain. This protein carries a signal peptide and shows the closest phylogenetic relationship to Helianthus annuus CML3. Its promoter contains ABA, methyl jasmonate (MeJA), and cold-response elements. Arabidopsis plants overexpressing SiCML6 showed significantly higher survival rates at −2 °C than wild-type plants. Under freezing stress, SiCML6-overexpressing lines exhibited reduced malondialdehyde content, relative electrolyte leakage, and ROS accumulation (H2O2 and O2−), along with increased proline, soluble sugars, soluble proteins, and total antioxidant capacity (T-AOC). SiCML6 elevated the expression of cold-responsive genes CBF3 and COR15a under normal conditions and further upregulated CBF1/2/3 and COR15a at 4 °C. Thus, low temperatures induced SiCML6 expression, which was potentially regulated by ABA/MeJA. SiCML6 enhances freezing tolerance by mitigating oxidative damage through boosted T-AOC and osmoprotectant accumulation while activating the CBF-COR signaling pathway. This gene is a novel target for improving crop cold resistance.

Peroxiredoxin (Prx) plays a role in maintaining the balance of intracellular reactive oxygen species. The peroxidase SiPrx gene from the Tianshan Snow Lotus (Saussurea involucrata) has been proved to significantly enhance the stress resistance of plants. In this study, the SiPrx gene was expressed heterogeneously in high-quality herbage Silphium perfoliatum L. (SP). After treatment with NaCl, the transgenic SP only exhibited partial leaf wilting, whereas the wild-type (WT) plants were on the brink of death. Simultaneously, physiological and biochemical assays indicated that under high-salt conditions, the content of malondialdehyde in the transgenic plants was significantly lower than that in the WT plants, while the activity of antioxidant enzymes was significantly higher than that in the WT plants. The expression of the SiPrx gene has been shown to significantly enhance the salt stress resistance of transgenic SP. Furthermore, after treatment at −10 °C for 48 h, the leaves of transgenic plants were able to maintain a certain morphological structure, whereas the WT plants were completely wilted. Physiological and biochemical index measurements indicated that all indicators in the transgenic plants were significantly better than those in the WT plants. Based on these findings, this study plans to overexpress the SiPrx gene extracted from Saussurea involucrata in Comfrey using the Agrobacterium-mediated method and then study its effects on the stress resistance of transgenic SP. The research results indicate that the SiPrx gene shows significant application potential in enhancing the cold resistance and salt tolerance of SP. This study provides a certain research basis and scientific evidence for the mining of stress resistance genes in Saussurea involucrata and the cultivation of new varieties of SP.

The full text of this preprint has been withdrawn by the authors as it was submitted and made public without the full consent of all the authors. Therefore, the authors do not wish this work to be cited as a reference. Questions should be directed to the corresponding author.

Weed stress remains a major limiting factor in cotton production, and glyphosate-tolerant varieties provide an effective solution for chemical weed control. However, achieving a balance between herbicide tolerance and agronomic physiological traits remains challenging. In this study, three hybrid combinations were generated by crossing a glyphosate-tolerant cotton line (GGK2) with conventional elite lines and were comprehensively evaluated. Gene expression analysis revealed that the classical detoxification gene GAT was significantly downregulated in all hybrid combinations, whereas the expression of GR79-EPSPS, a gene associated with glutathione metabolism and oxidative stress response, was markedly elevated, particularly in the GGK2 × Y4 combination. This differential expression pattern suggests that GR79-EPSPS may compensate for the reduced function of GAT by conferring oxidative protection under herbicide stress. Physiological determination indicated that hybrid combinations with enhanced GR79-EPSPS expression, especially GGK2 × Y5, exhibited superior photosynthetic pigment composition and photosystem II (PSII) efficiency, validating the role of GR79-EPSPS in maintaining photosynthetic stability. Agronomic trait assessment demonstrated that GGK2 × Y4 achieved significant biomass accumulation and yield improvement through heterosis, although fiber quality improvement was limited. This study effectively enhanced the herbicide resistance of conventional cotton through crossbreeding and revealed that the interaction between GR79-EPSPS and GAT can improve cotton tolerance to herbicides, thereby providing a breeding strategy for developing cotton varieties with both herbicide tolerance and superior agronomic traits.