Common bean is a major legume crop with high seed protein content and significant global importance for human consumption. Seedling establishment is a critical stage for plant survival, as the plant must develop in a potentially hostile environment where the seed coat or testa plays a crucial role. In this manuscript, we performed a proteomic study of bean seed coats and compared protein levels before and after germination. We found a significant number of proteins in the seed coat, of which 919 increased in abundance during germination, 717 decreased, and 1,567 remained unchanged. Among the various protein categories that increased in abundance, the nucleoside diphosphate kinase (NDPK) family and T2 ribonucleases, proteins involved in nucleotide metabolism, were used to analyse the transcript-translation relationship. In common bean, there are four NDPKs, three of which have been identified in the bean seed coat at both the protein and mRNA levels, and 13 ribonucleases T2, five of which have been identified as proteins and four as genes. The purine nucleotide degradation pathway in the seed coat has also been analysed, identifying proteins that could catalyze the degradation of these nucleotides to ureides. Overall, the data presented allow us to conclude that the seed coat is a functionally active tissue during germination and does not simply act as a protective barrier. Moreover, the proteomic profile reveals that this tissue exhibits a high nucleotide metabolic rate.
The DMP (Domain of Unknown Function 679 Membrane Proteins) gene family consists of proteins specifically expressed in plant membranes with functions associated with gamete fusion. However, its functional characterization remains largely unexplored in radishes (Raphanus sativus L.). In this study, a total of 13 DMP genes were identified in the radish genome; they were distributed unevenly across six chromosomes. Phylogenetic analysis revealed five distinct clades, based on the classification and nomenclature of this gene family in Arabidopsis. RsDMP9 was grouped with the haploid-inducing genes AtDMP8 and AtDMP9, which play a potential role in haploid induction. Light, growth, hormone, and stress-responsive elements were identified in the promoter of RsDMP9. Quantitative real-time polymerase chain reaction demonstrated the preferential expression of RsDMP9 in pollen, while other RsDMP genes showed differential expression in the roots, petals, and sepals. The RsDMP9 protein was confirmed to be localized to the plasma membrane. The identification and cloning of endogenous U6 promoter sequences from the radish genome were achieved based on the conserved U6 small nuclear RNA (snRNA) sequences of Arabidopsis thaliana. In vivo imaging and a dual-luciferase reporter system indicated that RsU6-6 exhibited strong transcriptional activity comparable to that of AtU6-1; truncation of RsU6-6 to 326 base pairs could enhance transcriptional activity, making it ideal for single guide RNA (sgRNA) expression and multiplex editing by avoiding promoter crosstalk. Additionally, the CRISPR/Cas9 system driven by RsU6-6 has been shown to achieve a high mutation frequency by protoplast transformation technology, thus demonstrating the effective validation of the CRISPR/Cas9 editing vector in radish protoplasts. These findings provide insights into the evolutionary conservation and functional diversification of RsDMP genes, and this protoplast-based editing system would facilitate effectively validating gene function and precision improvement of important traits in radish breeding programs.
Cucumber (Cucumis sativus L.) is a Cucurbitaceae plant that often suffers from fruit drop and deformity caused by excessive fruiting, poor growth, and unfavorable environmental conditions during cultivation.Forchlorfenuron [N-(2-chloro-4-pyridyl)-N'-phenylurea (CPPU)] is a plant growth regulator that has been widely used in the production of cucumbers and other horticultural plants because of its significant effects in promoting fruit set and enlargement. However, the underlying mechanism through which CPPU regulates cucumber fruit development remains unclear. To verify the role of CPPU in regulating cucumber fruit development, field experiments were conducted in both spring and autumn. The results confirmed that CPPU application significantly promoted fruit enlargement, shortened the time from flowering to harvest of marketable fruits, reduced fruit curvature, and increased the marketable fruit rate. Interestingly, we found that environmental conditions influence the regulatory effect of CPPU on fruit expansion. To investigate the molecular basis underlying CPPU-mediated regulation of fruit development, transcriptome analysis was performed. Firstly, 44 cross-stage differentially expressed genes (DEGs) were identified through differential gene analysis. Subsequent Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional annotation revealed that plant hormone signaling pathways are the key pathways mediating CPPU-regulated fruit expansion. Furthermore, five key candidate genes (CsaWIP2, CsPILS7, CsJOX2, CsGIR1, and CsAAA18193) responding to the CPPU signal were screened and preliminarily validated using machine learning and real-time quantitative polymerase chain reaction techniques. This study clarified CPPU's effect on cucumber fruit development, and the selected genes provided theoretical support for molecular breeding of cucumber and high-quality, high-yield cultivation optimization.
Glandular trichomes (GTs) are specialized epidermal structures in plants, which function as sites for the biosynthesis and storage of secondary metabolites, predominantly terpenoids. Traditionally, GT development and terpenoid biosynthesis were regarded as independent processes. However, accumulating evidence indicates that these two processes are often associated. In this review, we examine this relationship across multiple regulatory levels. At the spatiotemporal level, terpenoid accumulation is temporally associated with GT maturation. At the structural level, the subcuticular cavity formed during GT development provides a compartment for terpenoid storage. At the transcriptional level, key regulators such as MYB and bHLH transcription factors (TFs) have been shown to directly regulate both GT development and terpenoid biosynthetic pathways. We describe the developmental stages of GTs alongside the accumulation patterns of terpenoids and propose an integrated regulatory framework governing both processes in model plants and economically important crop species. We also discuss how this regulatory framework may inform strategies for engineering terpenoid-producing crops and constructing plant cell factories for terpenoid production.
Brassica juncea is an important and widely cultivated vegetable. Current genetic transformation techniques for this crop are limited by low efficiency. To establish a stable and efficient genetic transformation system for B. juncea, this study first combined Agrobacterium rhizogenes-mediated transformation with the novel visual marker gene RUBY. Rootless seedlings from two B. juncea genotypes, as explants, were infected by the A. rhizogenes strain K599 carrying a RUBY overexpression vector, successfully inducing red hairy roots. Subsequently, through exogenous hormone induction, a complete regeneration pathway was achieved, where transgenic positive hairy roots differentiated via callus to form regenerated shoots, establishing an efficient hairy roots–callus–regenerated shoots regeneration system. Ultimately, transgenic B. juncea plants carrying the RUBY gene, exhibiting distinctly red leaves throughout the plant, were obtained. Quantitative real-time polymerase chain reaction confirmed the high expression levels of the RUBY gene in these transgenic plants. It was worth noting that overexpression of RUBY gene may lead to growth abnormalities such as leaf wrinkling in some plants. This system using the visible marker of the RUBY gene significantly enhanced the efficiency and accuracy of screening for positive transformant plants and provided a new and efficient technical platform for the precise improvement of target traits and the functional analysis of genes in B. juncea.
The amino acid transporter (AAT) gene family encodes a group of membrane proteins in plants that mediate amino acid transport, regulate nitrogen allocation, and contribute to stress adaptation. In this study, a total of 102 LsAATs were identified in lettuce. They were classified into 12 subfamilies and distributed across all the chromosomes. Forty percent of them were expanded via gene duplication, and 23 and 18 LsAATs were segmentally and tandemly duplicated, respectively. Considerable variations in physicochemical properties, conserved motifs, and cis-acting elements were observed among these genes. The LsAATs and phenolic compounds regulated by continuous lighting and light quality were analyzed. Furthermore, three-dimensional structural models of light-regulated LsAATs were constructed and subsequently aligned with characterized homologs in other species. The results suggested that several light-regulated LsAATs might be involved in quality changes, nutrient uptake, long-distance transport, and stress adaptation. Overall, LsAATs are evolutionarily stable in plants and diverse in terms of their physicochemical properties and potential molecular biology.
Chili pepper (Capsicum annuum L.) is one of the most important vegetable crops worldwide, and leaf color mutants are valuable for studying chloroplast development and chlorophyll biosynthesis. This study used the yellow-green mutant 96-140YBM and its wild-type 96-140 as materials, aiming to fine-map candidate genes controlling the yellow leaf trait. On the basis of a preliminary mapping interval via bulked segregant analysis and bulked segregant RNA sequencing (BSA/BSR-seq) in the early stage, 21 single nucleotide polymorphism (SNP) markers were screened on chromosome 9 of pepper, which were developed into kompetitive allele-specific polymerase chain reaction (KASP) molecular markers. Genotyping analysis and quantitative trait locus (QTL) mapping were performed using 200 segregating F2 populations, and three intervals strongly associated with the yellow-green leaf trait were detected on chromosome 9 (690,139-760,388; 5,084,723-5,277,105; 5,281,991-5,516,629). Twenty-two genes were identified within the mapping intervals, four of which were related to chloroplast function. Capana09g000125 (named CaLAP2) was identified as the candidate gene. Sequence analysis revealed a base variation in its exon (GGA -> GAA), resulting in a glycine (Gly) to glutamic acid (Glu) substitution. This mutation site was developed into a KASP marker for genotype-phenotype association analysis in the F2 population, and validation results showed that the association accuracy between this mutation site and the phenotype reached 96.5%. This study established a fine-mapping technical system combining BSA/BSR-seq with KASP markers, which significantly narrowed the mapping interval and rapidly located key genes for the yellow-green mutation. This work lays an important foundation for elucidating the molecular mechanisms of yellow-green mutants in pepper, functional verification, and their application in molecular marker-assisted selection breeding.
The genus Allium, encompassing garlic (Allium sativum), onion (Allium cepa), Welsh onion (Allium fistulosum), Chinese chives (Allium tuberosum Rottler), and leek (Allium porrum), plays a crucial role in global agriculture and economy. Viral infections pose a significant threat to the cultivation of Allium crops, leading to substantial yield losses. This review summarizes the diverse array of viruses affecting Allium crops, detailing the symptoms manifested in infected plants. The different effects of these viruses in the various kinds of plant tissues and cell types are thoroughly studied, especially the intricate molecular, physiological, and cellular interactions that determine the dynamic relationship between the viral pathogen and its Allium hosts. Moreover, the review elucidates the detrimental effects of viral diseases on Allium crops and explores strategies for disease management and control. By shedding light on Allium crop viruses, this review aims to enhance our understanding of viral disease prevention in Allium cultivation.
In this study, a stably inherited short-vine mutant, G42cs, was identified and obtained from an EMS-mutagenized watermelon mutant library. Phenotypic characterization, genetic analysis, preliminary mapping of the short-vine gene, and research on its application in breeding were subsequently conducted on this mutant. Investigation of field agronomic traits revealed that the mutant exhibited significant differences from the wild type in traits such as plant height, tendrils, petioles, fruit pedicel length, and fruit size, while other traits showed no notable differences. Cellular staining observation of mutant tissues revealed that, compared to the wild type, the apical tissues of the mutant possessed more bud primordia or leaf primordia. The stem cells of the mutant were smaller than those of the wild-type watermelon, exhibiting a more compact and crowded arrangement, along with a higher number of cells per unit area. Measurements of plant height of the F2 population revealed that the short-vine trait is controlled by a single pair of recessive genes. Subsequently, BSA-Seq was performed using the two parents and the F2 population, which preliminarily mapped the short-vine gene to a 4.5 Mb region on chromosome 1. A dCAPS marker was developed to assist in screening for short-vine materials. Breeding backbone lines were developed using this short-vine mutant and applied in seed production. Assessments of seed yield per unit area and labor inputs showed that utilizing this short-vine trait in seed production can effectively reduce overall costs, demonstrating certain practical value. This model offers a new approach for watermelon seed production.
Eggplant (Solanum melongena L.), a major crop of the Solanaceae family, is valued for its rich nutritional profile, particularly the high anthocyanin content in the purple peel. Anthocyanin biosynthesis is primarily regulated by a network of transcription factors. Current research on MYB transcription factors in eggplant has predominantly focused on their roles as positive regulators, with limited insight into negative regulatory mechanisms. In this study, we cloned the SmMYB44-l gene. Bioinformatic and phylogenetic analyses revealed the presence of an EAR (LxLxL) repressor motif at the C-terminus of its encoded protein, and high sequence homology to StMYB44-l from potato. Expression analysis indicated a negative correlation between SmMYB44-l transcript levels and pericarp anthocyanin content. Subcellular localization experiment showed that SmMYB44-l localized to the nucleus. Transient expression assays demonstrated that SmMYB44-l repressed anthocyanin biosynthesis in tobacco (Nicotiana benthamiana) by downregulating both the MYB activator SmMYB75, and structural genes (NbCHS, NbF3H). Luciferase complementation imaging confirmed the absence of physical interaction between SmMYB44-l and SmMYB75. Overexpression of SmMYB44-l in both tobacco and eggplant suppressed anthocyanin accumulation. Yeast one-hybrid and luciferase reporter assays validated its direct repressive role in the regulation of anthocyanin biosynthesis.
Tomato brown rugose fruit virus (ToBRFV) represents a significant threat to global tomato production, resulting in decreased yields and compromised fruit quality due to the formation of brown, hardened spots on infected fruit. This study aimed to elucidate the molecular mechanisms for ToBRFV-induced lesions in tomato fruit using transcriptome sequencing and virus-induced gene silencing (VIGS) techniques. Transcriptome analysis was conducted on tomato fruit at green-ripe (L), and red-ripe (H) stages, examining three tissue types: brown lesions (B), non-brown areas of infected fruit (BC), and healthy controls (CK). A total of 34 differentially expressed genes (DEGs) related to phenylpropanoid biosynthesis were identified, with PAL (Solyc05g056170.3), C4H (Solyc05g047530.3), CAD (Solyc02g069250.3), and POD (Solyc02g094180.3) showing the highest transcript abundances in brown lesion tissues. Crucially, silencing POD (Solyc02g094180.3) increased tomato susceptibility to ToBRFV, accompanied by increased accumulation of hydrogen peroxide (H2O2), and superoxide anions (O2 center dot-). In contrast, silencing PAL (Solyc05g056170.3), C4H (Solyc05g047530.3), or CAD (Solyc02g069250.3) improved resistance and suppressed viral accumulation. Collectively, these findings indicate that these four genes are crucial regulators of lignin biosynthesis in tomato, and that the brown hardened lesions induced by ToBRFV are associated with lignin accumulation. Furthermore, POD plays a vital role in mediating resistance to ToBRFV by regulating reactive oxygen species. This study provides important insights into the molecular responses of tomato fruit, laying a foundation for breeding ToBRFV-resistant tomato varieties with improved fruit quality.
Nanomaterials, a group of novel materials with at least one dimension smaller than 100 nm, display great usage potential in multiple scientific disciplines such as drug design, cancer therapy, and improved crop production. This review focuses on nanomaterials and their applications in the plant field. The synthesis and classification of nanomaterials are first introduced, and the possible absorption and transport routes of nanomaterials in plants are discussed. Subsequently, the article summarizes recent advances in the utilization of nanomaterials and nano-mediated delivery systems in genetic transformation, growth and development regulation, and disease and pest insect control in plants, particularly those with agronomic importance. Several key research directions are finally proposed to advance the future application of nanobiotechnology in crop production.
Monoecious and andromonoecious cultivars of watermelon are characterised by the production of male and female flowers, or male and hermaphrodite flowers, respectively. Although the gene responsible for andromonoecy, designated as the a locus, has been identified, its fine-scale genetic mapping remains incomplete. In this study, we built upon our initial mapping of the a locus by performing QTL analysis on F2 populations from spring 2021 (187 plants), and autumn 2021 (137 plants), revealing a stable preliminary region for the a locus on Chr3:29,252,650-30,021,268 bp. By expanding the ZXG1555 & times; COS-F2 population to 710 plants, we fine-mapped the a locus to an 82.10 kb interval (Chr3: 29,488,876-29,570,980 bp), which contains five candidate genes. Sequence comparison and transcriptional expression analysis indicated that ClACS7, which encodes 1-aminocyclopropane-1-carboxylate synthase 7, is the most probable candidate gene for this locus. Furthermore, we genotyped 32 natural watermelon populations (2 andromonoecious and 30 monoecious) using the molecular marker Chr03_29539131, which is closely linked to the andromonoecious trait. The results demonstrate that Chr03_29539131 can be effectively used for screening andromonoecy in watermelon and for molecular marker-assisted breeding.
Excessive nitrogen (N) fertilization in cucumber cultivation reduces nitrogen-use efficiency (NUE) and imposes severe environmental costs. Improving NUE requires coordinated regulation of systemic nitrogen signaling (SNS), which directs root foraging toward nitrate (NO3-)-rich zones, and nitrate uptake capacity, which defines the rate of N acquisition. Here, we established a hydroponic split-root assay and a 15N-nitrate tracing system to quantify SNS responsiveness and nitrate uptake capacity across 56 cucumber (Cucumis sativus L.) germplasms. Significant variation was identified across the germplasm, resulting in the selection of G47 (high SNS responsiveness and nitrate uptake capacity), and G23 (low SNS responsiveness and nitrate uptake capacity), as contrasting accessions for evaluation alongside the reference cultivar 9930. Comparative analysis of these three genotypes revealed that G47 exhibited superior low-nitrogen (LN) stress tolerance, showing the smallest declines in biomass and chlorophyll, incurring the lowest oxidative and membrane damage, and demonstrating greater osmolyte and antioxidant accumulation alongside sustained nitrate assimilation. Comparative transcriptomic analysis revealed strong induction of gamma-aminobutyric acid (GABA)-associated metabolism in G47, with the GABA pathway gene CsGS1 markedly upregulated. Functionally, foliar GABA application enhanced, whereas the GABA-biosynthesis inhibitor 3-mercaptopropionic acid (3-MP) diminished, LN tolerance. These findings identify GABA as a metabolic modulator of LN adaptation in cucumber and establish an integrated framework based on SNS responsiveness and nitrate uptake capacity for discovering high-NUE germplasm and molecular targets for nutrient-efficient breeding.
The stable expression of integrated transgenes remains a major restriction in plant transformation, as different vector backbones and host contexts often lead to variable or silenced expression. Systematic evaluations of the binary vector architecture and broadly applicable visual markers for rapid line selection are still lacking. In this study, we developed a streamlined 2A-linked unit of CYP76AD1, DODA, and Glucosyltransferase (RUBY)-based chromogenic reporter system and validated its robustness in the transformation in Arabidopsis thaliana, tobacco (Nicotiana tabacum), and tomato (Solanum lycopersicum). A comparative analysis of two binary vector backbones revealed strong structural effects on the stability of expression, with one backbone enabling consistently high pigmentation in tomato. RUBY's intensity provides an immediate readout of transgene activity and allows the rapid identification of single-copy, stably expressing lines through seedling segregation. RUBY expression does not influence plants' growth or epidermal development, demonstrating excellent biocompatibility. We also established an inducible pXVE::RUBY module and a CRISPR-associated protein 9 (Cas9)-porcine teschovirus-1 2A peptide (P2A)-RUBY system for real-time monitoring of transgene induction and visualizing genome editing events. This platform offers an efficient and readily implementable strategy to overcome the disconnect between transgenes' integration and expression, while substantially improving the overall performance of plant transformation and genome editing pipelines.
CBL-interacting protein kinases (CIPKs) serve as key regulators in plant Ca2+ signaling pathways, playing a vital role in responding to abiotic stresses such as salinity and drought. However, systematic studies on the CIPK gene family in lettuce (Lactuca sativa L.) remain scarce. In this study, comprehensive identification, structural analysis, evolutionary analysis, and stress response analysis of the CIPK gene family were conducted based on the lettuce reference genome. A total of 32 LsCIPK genes were identified, which were distributed on nine chromosomes. Phylogenetic analysis demonstrated that 32 LsCIPKs could be divided into five evolutionary branches. All LsCIPK proteins contained a typical protein kinase domain and an NAF domain (CBL-interacting domain). Promoter cis-element analysis indicated that most LsCIPK genes are rich in cis-elements associated with light response, hormone response, and abiotic stress. Collinearity analysis indicates that the expansion of this gene family was primarily driven by segmental duplication, and the Ka/Ks ratios for all eight duplicate gene pairs were less than 1, suggesting that the family as a whole is under purifying selection. Expression analysis revealed significant expression changes in multiple LsCIPK genes. Among them, the expression of LsCIPK7, LsCIPK26, and LsCIPK32 was strongly induced. Further qRT-PCR results confirmed the transcriptome trends. Subcellular localization analysis of LsCIPK32 revealed that this protein is primarily distributed in the nucleus and cell membrane. This study provides candidate genes and theoretical support for deciphering the regulatory mechanisms of the lettuce CBL-CIPK signaling pathway and for breeding salt-tolerant and drought-resistant lettuce varieties.
With the advancement of agricultural mechanization, the development of crop varieties suitable for mechanized harvesting has become an important breeding objective. In bitter gourd (Momordica charantia), increasing fruit pedicel length (FPL) is considered a key trait for improving harvest efficiency. However, the genetic and molecular mechanisms controlling FPL remain largely unknown. In this study, two contrasting lines, 23S083 (long FPL), and 23S184 (short FPL), were selected for comparison. Microscopic analysis revealed that the longer pedicel in 23S083 was attributable to both increased cell length and number compared to 23S184. Using F1 and F2 populations derived from these parents, the major locus McFPL1 was initially mapped to a 2.46 Mb region on chromosome 3 through BSA-seq. Fine mapping with 15 polymorphic markers further narrowed the candidate region to 255.059 kb. Among the 21 genes with mutations in this interval, Moc03g21510, which encodes an ABCG subfamily ATP-binding cassette transporter, was proposed as the most promising candidate gene. During the elongation of the fruit pedicel, the expression level of this gene was significantly higher in 23S083 than in 23S184. Sequence analysis identified 20 SNPs and eight InDels in its 3'UTR, suggesting that these variations may influence mRNA stability and thus regulate pedicel elongation. Furthermore, the co-segregating marker developed from these variations accounted for approximately 76.7% of the phenotypic variation in FPL within the natural bitter gourd population. These results provide valuable genetic insights into FPL formation and will facilitate the molecular breeding of mechanization-adapted bitter gourd varieties.
The aromatic quality of non-heading Chinese cabbage (Brassica chinensis L., NHCC) vars Xiangqingcai (XQC), is significantly enhanced when cultivated in China's Suzhou region. To investigate the chemical and molecular basis of this characteristic fragrance, an integrated analysis of volatile organic compounds (VOCs), and transcriptomes from three key Xiangqingcai (XQC) cultivars (black leaf [FB], yellow leaf [FH], and Xiuhuajin [FX]) were performed using headspace solid-phase microextraction/gas chromatography-mass spectrometry (HS-SPME-GC-MS) and RNA sequencing, with Suzhouqing (SZQ) as the control. Comparative analysis identified 56 VOCs with significantly different abundances between the XQC cultivars, and SZQ. Thirteen of these were identified as key aroma-active compounds, belonging to diverse chemical classes including nitriles, terpenes, alkenes, aromatic hydrocarbons, esters, ketones, alcohols, and heterocyclic alkanes. Enrichment analysis indicated that sesquiterpenoid and triterpenoid biosynthesis, phenylalanine metabolism, and sulfur-related metabolism were the primary pathways involved. Critical odorants such as beta-caryophyllene, phenylacetaldehyde, and 1,8-cineole were identified as major contributors. Key genes encoding enzymes central to the biosynthesis of these aromatic compounds were also uncovered. This study provides a molecular foundation for understanding aroma regulation in NHCC and offers practical targets for breeding programs aimed at improving flavor quality.
Tipburn (TB) is a devastating physiological disorder in lettuce (Lactuca sativa) linked to localized calcium (Ca2+) deficiency. While biparental population studies have identified tipburn-linked QTLs, the core genetic mechanisms across diverse germplasm remain poorly understood. We utilized an integrative physiological-genetic framework to dissect TB genetic architecture in a diversity panel of 498 lettuce accessions evaluated over six years. Structural equation and response surface modeling established that TB risk is driven by a supply-demand imbalance regulated by plant biomass (PB) and developmental rate (DS). Although Ca2+ content significantly influenced TB incidence, it did not account for all phenotypic variance, suggesting the existence of Ca2+- independent resistance pathways. To isolate these, we performed GWAS on residual TB that accounted for PB, DS, and bulk Ca content, effectively decoupling plant physiology from resistance. We identified a stable cellular integrity hub on chromosomes 2 (BIN 2.21) and 8 (BIN 8.04), providing resistance regardless of biomass, developmental rate, or bulk Ca2+ status. Conversely, a major locus on chromosome 7 (BIN 7.17) acted as a developmental hub, where resistance is entirely mediated by bolting time and mineral partitioning. Candidate gene analysis at BIN 2.21 identified phosphoinositide phospholipase (PLC) as a putative primary regulator; sequence analysis revealed a highly divergent PLC protein variant strongly associated with the lowest TB incidence. Other candidates include catalases (BIN 8.04) involved in oxidative stress mitigation and myosin-11 motor proteins. Our findings move beyond simple trait associations to identify stable, vigor-independent genetic targets, providing a roadmap for breeding high-yielding, tipburn-resilient lettuce cultivars.
