The review begins by untangling terminology that has confused the field for years. Floral competence, induction and initiation are often used interchangeably, but they describe distinct stages in a developmental sequence. Competence means that a mature bud is capable of responding; induction is the environmental or physiological signal that actually shifts bud fate; initiation marks the first detectable changes in the meristem; and bud break, panicle emergence and anthesis come later. This distinction matters enormously for growers, because a treatment that merely accelerates bud break, such as a nitrate spray on a mature bud, can be mistaken for a true inductive signal when it is really acting downstream of the critical decision point.

Temperature emerges as the most consistently supported environmental cue, yet the review stresses that no universal threshold exists. Controlled experiments point to inductive regimes near 19 to 15 degrees Celsius during the day and 15 to 10 degrees at night. A particularly vivid comparison comes from potted Tommy Atkins trees held at either 13 or 25 degrees Celsius for three months: nearly 100 percent of the cool-treated trees flowered, while none of the warm-treated trees did. But the story does not end there. A post-induction study of Kensington mango found that inflorescences developed at 20/10, 25/15 and 30/20 degree day/night regimes, yet failed entirely at 15/5 degrees, showing that temperatures promoting induction are not necessarily optimal for later panicle development. Field data from Australian selections further confirm that the relevant minimum and maximum temperatures differ among cultivars.

Water status adds a second, non-linear gate to the flowering decision. In low-latitude experiments, a water deficit lasting roughly five weeks promoted earlier or more intense flowering in Kensington Pride and Irwin mango, suggesting that moderate pre-induction stress can partially substitute for seasonal cooling in some tropical settings. Earlier container work showed that temperature and water stress interact rather than acting as independent switches. The review is careful to note, however, that the direction of the response changes dramatically with severity and timing. Severe drought, or drought imposed during panicle expansion or near anthesis, can reduce photosynthesis, panicle survival, pollen function and fruit set. Drought is best understood as a context-dependent modifier of bud competence and carbon balance, not a universally beneficial flowering treatment.

The hormonal dimension of flowering centres on an interplay between gibberellins, which generally promote shoot extension and can antagonize reproductive competence, and abscisic acid, which has recently been linked to floral transition through direct molecular evidence. In the 13 versus 25 degree comparison, cool treatment was associated with lower GA3 in wood and bark and higher ABA in wood, alongside nearly complete flowering. This supports a local or vascular ABA-GA shift during induction, but the review cautions that it does not show all tissues or all cultivars experience the same hormone changes. Gibberellin and ABA responses are best interpreted as tissue- and treatment-specific rather than as universal rules.

The strongest recent gene-level evidence comes from work on mepiquat chloride, a quaternary ammonium growth retardant. When mepiquat chloride induced floral transition, gibberellin levels fell, expression of gibberellin 2-oxidase genes rose, ABA accumulated, and the ABA-responsive genes MiNCED1 and MiABI5-like7 increased in expression. Critically, exogenous ABA accelerated the transition, an ABA-inhibitor treatment delayed it, and biochemical and transgenic assays showed that MiABI5-like7 directly activates MiFT3, a florigenic gene. Silencing MiABI5-like7 delayed the transition, whereas ectopic expression promoted early flowering. This constitutes direct evidence for an ABA-responsive MiABI5-like7-MiFT3 regulatory module in mango, though the review emphasizes that this does not automatically mean fruit load, sugar signals, circadian rhythms or plant age regulate ABA in the same way.

The molecular framework extends well beyond this module. Mango homologues of FLOWERING LOCUS T act as florigenic pathway integrators, while TERMINAL FLOWER 1 homologues function as anti-florigens. Three MiFT genes have been isolated and functionally compared, with MiFT1 promoting early flowering in Arabidopsis, and four MiTFL1 genes delaying flowering in the same heterologous system. Downstream integrators include MiSOC1, MiAP1, MiLFY and the repressive MADS-box genes MiSVP1 through MiSVP4. The CONSTANS-LIKE family adds further complexity: two cultivar-derived variants, MiCOL14B-GQ and MiCOL14B-JH, bind MiFT promoters but have opposite effects on transcription and flowering. Newer candidates include 14-3-3 proteins, a RING zinc-finger protein called MiRZFP34, SLENDER RICE-like DELLA genes MiSLR1 and MiSLR2, and GA receptor genes MiGID1A and MiGID1B, all of which promoted early flowering when overexpressed in Arabidopsis.

The review is explicit about the limits of such heterologous evidence. A gene can change flowering time in Arabidopsis without being the same limiting regulator in a mature mango bud, and the review organizes all molecular players into a three-tier hierarchy: direct mango hormone or gene perturbation, functional tests in a heterologous system, and transcriptome or co-expression association. Fruit load, for example, has a direct link to FT/TFL1 expression through studies in Shelly mango, where low fruit load was associated with earlier MiFT1 upregulation in winter leaves and high fruit load with higher expression of anti-florigenic MiTFL1 genes. But the claim that sugars, circadian transcripts or plant age regulate ABA during mango floral induction remains correlative rather than causally established. The miR156-SPL age pathway offers a plausible comparative framework for juvenility effects, but direct mango experiments are still lacking.

Chemical growth retardants receive careful treatment as mechanistic probes rather than as prescriptions. Paclobutrazol, a triazole inhibitor of early gibberellin biosynthesis, consistently lowered GA concentrations in wood and bark of tropical Tommy Atkins trees, while potassium nitrate increased zeatin-type cytokinins near induction. But no single paclobutrazol dose can be recommended across all orchards, because product concentration, canopy size, cultivar, soil, climate and application date all change exposure. Published experimental rates range from 0.25 to 3 millilitres or grams per metre of canopy spread depending on the study, and high rates may compact panicles or leave residues for months. Ethephon, which releases ethylene, shows similarly stage-dependent and cultivar-dependent effects, with responses appearing within two to five weeks and new growth emerging six to twenty-one weeks later that could be floral or non-floral.

The integrated model that emerges is a two-gate framework with real implications for a warming, less predictable climate. Gate one is bud competence, determined by shoot maturity, seasonal temperature history, water status, source-sink balance and juvenile state. Gate two is signal execution, in which gibberellin restraint, ABA responses, cytokinin and ethylene effects, and the FT/TFL1 balance determine whether a competent bud enters the floral pathway. The review lays out priority experiments: multi-year, cultivar-stratified field trials recording hourly temperature and exact bud fate; tissue-specific measurements of ABA, GA3, GA20, cytokinins and sugars at matched developmental stages; mango-compatible silencing, editing or transient assays for key modules like MiABI5-like7-MiFT3 and MiCOL14B; and paired measurement of flowering with panicle quality, fruit set and residue data. In an era of irregular rainfall and shifting winter temperatures, understanding these gates may prove essential for keeping the king of fruits flowering reliably across the tropics and subtropics.

Subject of Research: Environmental, hormonal and molecular regulation of flowering in mango (Mangifera indica)

Article Title: Environmental sensing, hormonal crosstalk and molecular control of mango flowering in Mangifera indica L.

Article References: Liang, F. (2026). Environmental sensing, hormonal crosstalk and molecular control of mango flowering in Mangifera indica L.. Discover Plants, 3(1), Article 466. https://doi.org/10.1007/s44372-026-00947-9

Image Credits: AI Generated

DOI: 10.1007/s44372-026-00947-9

Keywords: mango, flowering, floral induction, gibberellin, abscisic acid, FT/TFL1, temperature, water stress, paclobutrazol, circadian regulation, MiCOL14B, climate resilience

RUBY was developed as a genetically encoded visual reporter that produces a vivid red betalain pigment, the same class of compounds that gives beets their characteristic color. Unlike green fluorescent protein or luciferase-based systems, RUBY requires no exogenous substrate, no specialized microscopy equipment, and no expensive imaging workflows. A researcher can simply look at a seedling, a leaf, or a callus and see whether a transgene is being expressed. That simplicity has made it attractive for tasks ranging from confirming transformation efficiency to screening genome-editing events, identifying haploid plants in maize and tomato breeding programs, monitoring transgene stability in lettuce, and even teaching genome editing in undergraduate classrooms.

The reporter works by reconstituting a three-enzyme betalain biosynthetic pathway borrowed from beet. The enzymes act sequentially on substrates drawn from the plant’s own tyrosine metabolism, ultimately producing the red pigment betanin. Because the pathway taps into central aromatic amino acid metabolism, the authors of the new study, led by Amandeep Cheema, Kasavajhala V. S. K. Prasad, Enamul Huq, and Anireddy S. N. Reddy at Colorado State University and the University of Texas at Austin, suspected that constitutive RUBY expression might not be metabolically neutral. Tyrosine sits at the head of the shikimate pathway, a hub that feeds the synthesis of a wide range of compounds, including the auxin precursor pool and other aromatic metabolites that influence growth.

To test that suspicion, the team generated independent transgenic Arabidopsis lines expressing RUBY and compared them with wild-type plants across the full life cycle. The differences were striking. RUBY-expressing plants were significantly smaller than controls and produced fewer leaves. They flowered later, a phenotype that in Arabidopsis often signals disruption of the hormonal and transcriptional networks that govern the transition from vegetative growth to reproduction. Perhaps most consequential for any breeding or seed-production application, the plants frequently developed malformed siliques, the seed-bearing pods of the flower, and produced a markedly reduced yield of seeds.

Below ground, the story was just as dramatic. Root architecture in the RUBY lines was severely impaired, with a pronounced reduction in the number of lateral roots. Lateral root formation is one of the most hormone-sensitive processes in plant development: auxin, the archetypal plant hormone, acts as a local morphogenetic trigger that specifies lateral root founder cells, and both auxin transport and gibberellin signaling feed into the regulatory network controlling lateral root organogenesis. A root system stripped of lateral roots is compromised in its ability to forage for water and nutrients, which likely compounds the above-ground growth defects.

One obvious hypothesis was that the plants were simply starved for auxin, and that supplementing the hormone would rescue the phenotype. The researchers tested this by applying indole-3-acetic acid, the principal natural auxin, to the RUBY-expressing plants. It did not help. The failure of IAA to restore normal development suggested that the disruption ran deeper than a straightforward hormone deficit, pointing instead to a broader perturbation of metabolic homeostasis that could not be corrected by adding back a single hormone.

Targeted metabolomic profiling of the RUBY lines confirmed that suspicion. The analysis revealed widespread alterations in amino acid and hormone pools. Levels of active indole-3-acetic acid were reduced, as were levels of gibberellins, the hormone family that promotes stem elongation, germination, and floral initiation. At the same time, the plants accumulated auxin precursors, indicating a bottleneck or diversion in the auxin biosynthetic pathway. Accumulation of indole-3-acetamide, an auxin precursor, has previously been shown to curtail growth in Arabidopsis by repressing ribosome-biogenesis and development-related transcriptional networks, and tryptophan deficiency is known to retard organ growth by slowing cell expansion. The metabolic signature of the RUBY lines is consistent with this kind of precursor-driven growth inhibition, layered on top of a gibberellin shortfall that would plausibly explain the delayed flowering and reduced stature.

The most convincing piece of evidence came from a genetic dissection of the reporter itself. The team disrupted RUBY expression by suppressing the third enzyme in the pathway, a glucosyltransferase that catalyzes the final step in betanin production. When that step was blocked, the RUBY-associated developmental phenotypes were restored to wild type. In other words, it is not the presence of the transgene or the act of transformation that damages the plants, but the flux of metabolites through the complete betalain pathway. Interrupting the pathway at its final step abolishes both the visible pigment and the collateral metabolic damage, cleanly linking the reporter’s biochemistry to its developmental side effects.

The study is not the first hint that heterologous betalain production can shake up plant metabolism. Recent work in tobacco showed that heterologous biosynthesis of betanin triggers broad metabolic reprogramming, and the relaxation of tyrosine pathway regulation is known to underlie the evolution of betalain pigmentation in the Caryophyllales, the plant order to which beets belong. What makes the new results consequential is the sheer breadth of RUBY’s adoption. The reporter has been built into T-DNA vectors for maize transformation, adapted into split-assay formats for detecting protein-protein interactions and DNA-protein interactions in planta, and used as a visual splicing reporter. If constitutive RUBY expression perturbs hormone and amino acid homeostasis in Arabidopsis, researchers using the system for developmental studies, particularly studies of growth, flowering time, or root architecture, may be measuring the reporter’s side effects alongside the biology they intended to study.

The authors argue that the way forward is not to abandon RUBY but to tame it. Because the damage is caused by pathway flux rather than by the reporter construct itself, regulated expression systems, such as inducible promoters or tissue-specific promoters that confine betalain production to a small subset of cells or a defined time window, should dramatically reduce the metabolic burden while preserving the reporter’s visual punch. Such strategies would let researchers keep the convenience that made RUBY famous, the naked-eye readout with no substrates and no instruments, while avoiding the hidden trade-offs now documented in Arabidopsis. For a tool that has been celebrated for making plant biology visible to the naked eye, the lesson of the new study is that some of what it reveals may be an artifact of its own chemistry, and that the next generation of RUBY experiments will need to be designed with that in mind.

Subject of Research: Metabolic and developmental side effects of the betalain-based RUBY visual reporter in Arabidopsis thaliana

Article Title: RUBY expression alters development and metabolism in Arabidopsis

Article References: Cheema, A., Prasad, K. V. S. K., Huq, E., & Reddy, A. S. N. (2026). RUBY expression alters development and metabolism in Arabidopsis. Plant Molecular Biology, 116(5), Article 102. https://doi.org/10.1007/s11103-026-01764-0

Image Credits: AI Generated

DOI: 10.1007/s11103-026-01764-0

Keywords: RUBY reporter, betalain, Arabidopsis thaliana, auxin, gibberellin, plant hormones, lateral roots, metabolomics, plant biotechnology, genetically encoded reporters, tyrosine metabolism, plant development

The team set out to dissect the genetic architecture of internode number and internode length, the two traits that together define plant height in rice. Rather than relying on classical crosses between two parents, the researchers deployed a genome-wide association study, or GWAS, across a remarkably diverse panel of 429 rice accessions. This population-scale approach exploits the natural historical recombination of the rice genome: if a particular DNA variant consistently tracks with shorter internodes across hundreds of unrelated varieties, that variant likely sits near a gene genuinely involved in the trait. The scale of the genotyping was impressive in its own right—3.16 million high-quality single nucleotide polymorphisms were used to scan the twelve rice chromosomes for statistical associations with each measured trait.

The scan paid off. The analysis identified 34 significant marker-trait associations linking specific genomic regions to internode characteristics, and among these the researchers pinpointed four quantitative trait loci, or QTLs, that had not been described before. Within the most compelling regions, two candidate genes emerged and were christened Internode number and length 1 (INL1) and INL2. Functional annotations suggested that INL1 encodes a cytochrome P450 enzyme, while INL2 encodes a zinc finger protein transcription factor. Both gene families are heavyweight players in plant biology: cytochrome P450s catalyze an enormous range of biochemical reactions, including steps in hormone synthesis, and zinc finger transcription factors act as molecular switches that regulate suites of downstream genes.

The choice of these two gene families is particularly intriguing given what is already known about stem elongation. Gibberellins, a class of phytohormones, are the principal drivers of internode elongation, and the Green Revolution sd1 gene itself encodes a gibberellin biosynthesis enzyme. Cytochrome P450 enzymes have repeatedly surfaced in this arena—EUI1, another rice P450 monooxygenase, modulates gibberellin responses to control internode elongation, and several P450s participate in brassinosteroid biosynthesis, a hormone pathway that crosstalks extensively with gibberellins. Similarly, Cys2/His2 zinc finger proteins in rice have been shown to repress SD1/OsGA20ox2, tying transcriptional control directly to gibberellin production. INL1 and INL2 therefore fit neatly into an emerging picture of height regulation as a multi-layered network combining hormone metabolism and transcriptional governance.

Correlation, however, is not causation, and the team moved to functional validation using CRISPR/Cas9 genome editing. By knocking out INL1 and INL2 in rice, the researchers created plants in which these genes no longer function. The result was unambiguous: the knockout lines displayed shorter internodes and reduced overall plant height compared with wild-type plants. This loss-of-function phenotype provides strong experimental evidence that both genes act as positive regulators of internode elongation—when they are disabled, stems grow shorter. For breeders, genes that reduce height when knocked out are exactly the kind of raw material needed for dwarf breeding programs aimed at improving lodging resistance.

To understand how the knockouts produce their dwarfed stature, the researchers turned to transcriptomics, measuring genome-wide gene expression changes in the edited plants. The analysis revealed that loss of INL1 and INL2 differentially modulates gibberellin metabolism, ultimately leading to the dwarf phenotype. In other words, disrupting these genes perturbs the hormonal machinery that normally drives cell elongation in the stem, choking back the growth of internodes. This places the two new genes upstream of, or within, the gibberellin pathway and suggests that they coordinate the metabolic flux that fuels stem extension.

Beyond gene function, the study explored natural allelic variation in INL1 and INL2 through haplotype analysis. Haplotypes are characteristic combinations of DNA variants inherited together at a locus, and different haplotypes often produce different trait values. The researchers found that accessions carrying the HapA type of the two genes had shorter internodes than those carrying other haplotypes. This means that favorable, height-reducing alleles of OsINL1 and OsINL2 already exist within the rice gene pool, circulating among natural and cultivated varieties. Rather than waiting for new mutations, breeders can in principle track these haplotypes with DNA markers and introgress them into elite cultivars through marker-assisted selection.

The practical implications extend well beyond plant architecture trivia. Lodging is a chronic threat to rice production worldwide, particularly as extreme weather events intensify and high-yielding varieties carry heavier panicles atop their stems. Lodged crops suffer reduced photosynthesis, impaired grain filling, greater disease pressure and harvest losses. Because plant height is determined by the number and length of individual internodes, genes that fine-tune each segment offer breeders granular control: reducing the length of specific internodes can lower the center of gravity and strengthen the culm without necessarily sacrificing the biomass or yield potential that taller plants sometimes confer. The authors note that the favorable alleles of INL1 and INL2 reduce height and can be further used in rice dwarf breeding to improve lodging resistance.

There is also a broader scientific payoff. Most dwarfing work in rice has centered on sd1 and a handful of related loci, and researchers have increasingly argued that additional dwarfing or semi-dwarfing genes are needed to diversify the genetic basis of height control and avoid the vulnerabilities of over-reliance on a single locus. By combining a large, diverse association panel, dense SNP coverage, new QTL discovery, CRISPR validation and transcriptomic profiling, this study demonstrates a full pipeline from statistical signal to mechanistic hypothesis to breeding-ready allele. The finding that a cytochrome P450 and a zinc finger transcription factor converge on gibberellin metabolism enriches the known regulatory map of stem growth and may illuminate how gibberellin homeostasis is tuned in other cereal crops such as wheat and barley, where similar architecture principles apply.

As global demand for rice continues to climb against a backdrop of shrinking arable land and volatile weather, the genetics of stem architecture has become a frontline topic in crop science. The identification of INL1 and INL2 shows how modern genomics—millions of SNPs, hundreds of accessions, precision gene editing and hormone-level transcriptomics—can convert a field-measurable trait like internode length into molecular tools that breeders can deploy. If the favorable haplotypes of these two genes perform as hoped when pyramided into elite backgrounds, the humble rice stalk may soon stand a little shorter, and a great deal steadier, in the fields that feed the world.

Subject of Research: Genetic basis of internode length and plant height regulation in rice

Article Title: Candidate genes identification for internode length in rice via genome-wide association studies

Article References: Li, B., Sun, J., Yao, Q., Ding, Y., Geng, Y., Bao, Y., Ang, Y., Jiang, H., Yang, Z., Shi, Y., Jiang, J., Dang, X., Zhang, C., Ergashev, M. A., Li, M., Ali, J., Li, Z., & Liu, E. (2026). Candidate genes identification for internode length in rice via genome-wide association studies. Theoretical and Applied Genetics, 139(10), Article 294. https://doi.org/10.1007/s00122-026-05395-3

Image Credits: AI Generated

DOI: 10.1007/s00122-026-05395-3

Keywords: rice, genome-wide association study, internode length, plant height, INL1, INL2, gibberellin, CRISPR/Cas9, lodging resistance, dwarf breeding, cytochrome P450, zinc finger transcription factor

The research team, led by Yuanqian Ni and supervised by Zhaosen Xie and Youmei Li, took advantage of a natural contrast between two grapevine cultivars. ‘Einset Seedless’, abbreviated ENT in the study, tends to produce inflorescences at the lower tendril nodes of its lateral shoots, while ‘Pinot Noir’, or PN, overwhelmingly produces true tendrils at the equivalent positions. By comparing these two varieties node by node, the researchers could ask a precise question: when the same meristem faces the same choice, what is different inside the cells of a plant that flowers versus a plant that climbs?

The homology of tendrils and inflorescences in grapevine is well established. Classical anatomical work showed that both organs arise from the same uncommitted primordia on lateral shoots, and earlier molecular studies found that floral meristem identity genes are expressed even in developing tendrils, as if the tendril were an inflorescence that never quite committed to flowering. Decades ago, pioneering experiments by Srinivasan and Mullins demonstrated that isolated tendrils could even be coaxed into forming inflorescences in vitro, hinting that the switch between the two fates is chemically malleable. What the new study adds is a genome-wide, node-resolved map of the transcriptional landscape in which that switch is thrown.

The team first quantified the anatomical difference, confirming that ENT achieved a markedly higher flowering rate at tendril nodes one through four than PN did. They then harvested tissue from specific tendril nodes in both cultivars and performed RNA sequencing, using an intersection and exclusion strategy to isolate 549 differentially expressed genes that distinguish inflorescence-prone from tendril-prone tissue. When those genes were subjected to Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis, two signaling systems rose to the top: plant hormone signal transduction and mitogen-activated protein kinase cascades. In other words, the decision between flower and tendril appears to be broadcast through the cell by hormonal and phosphorylation-based communication channels rather than by a single master switch.

To move beyond a static snapshot, the researchers applied Mfuzz clustering, a computational method that groups genes according to the shape of their expression trajectories across a developmental series. This revealed that multiple expression programs rise and fall in patterns that track the flowering gradient running along the shoot, from the most inflorescence-prone basal nodes to the tendril-dominated upper nodes. Across every dynamic cluster, plant hormone signal transduction emerged as the predominantly enriched pathway, underscoring that phytohormones are not merely participants in this process but sit at its very center.

Guided by that transcriptional evidence, the team measured the endogenous levels of two key hormones directly in the nodal tissues: zeatin, the classic cytokinin that generally promotes reproductive meristem activity and flowering, and gibberellin GA3, which is more often associated with stem elongation and vegetative growth. The striking result was that the ratio between the two, rather than the absolute level of either hormone alone, paralleled the flowering gradient across nodes and correlated with the gene expression trajectories identified by clustering. A high zeatin-to-GA3 ratio accompanied the inflorescence-prone state, while a lower ratio accompanied tendril formation. This provides concrete physiological support for a cytokinin-gibberellin interaction model in which the balance between these two antagonistic hormones helps determine whether a lateral meristem matures into a flower-bearing branch or an elongating, climbing tendril.

The hormone story dovetails with a long history of viticultural observation. Growth retardants that suppress gibberellin synthesis have been known since the 1960s to influence fruitfulness in grapes, and cytokinin treatments have been shown to convert tendril primordia into inflorescences, with the success of that conversion depending on the genotype. The famous ‘green revolution’ dwarfing mutation in grapevine, which links reduced gibberellin response with enhanced floral induction, fits the same pattern. What the new transcriptomic work contributes is the mechanistic scaffolding: it shows that the endogenous hormone ratio in the organ itself, not just externally applied chemicals, tracks the developmental outcome, and that the downstream transcriptional response is organized into coherent, flowering-correlated trajectories.

Within the pool of differentially expressed transcription factors, one gene stood out. A MADS-box gene named FRUITFULL-LIKE, or VvFUL-L, was markedly upregulated in PN tendrils compared with inflorescence-prone ENT tissue. MADS-box transcription factors are the celebrated architects of floral development, and the FRUITFULL lineage in particular is known from arabidopsis and tomato to regulate meristem identity, flowering time, and inflorescence architecture. To probe what VvFUL-L might be doing, the team overexpressed it heterologously in arabidopsis. The transgenic plants flowered earlier than normal and produced inflorescences with reduced branching, phenotypes consistent with a role in steering lateral meristem development. The authors suggest that VvFUL-L may help tip the uncommitted grapevine lateral meristem toward the tendril program, although confirming that function in grapevine itself will require further work in the crop.

The agronomic implications are immediate and tangible. Excessive tendril growth increases vineyard management costs because tendrils must be removed or redirected by hand or machine, and they can girdle shoots and interfere with canopy machinery. If the cytokinin-to-gibberellin ratio and regulators like VvFUL-L can be manipulated, whether through breeding, targeted gene editing, or growth regulator programs, growers could eventually favor inflorescence formation at the basal nodes where fruit is wanted and suppress the runaway tendril production that wastes the vine’s resources. The study’s authors frame their findings as a foundation for future molecular and breeding studies aimed at managing tendril growth, and the identification of a small set of hormone-responsive genes and a candidate transcriptional regulator is exactly the kind of entry point such efforts require.

There is also a broader evolutionary resonance in the result. Across the grape family, the Vitaceae, tendrils and inflorescences are thought to be variations on a single ancestral organ, and expression studies of APETALA1, FRUITFULL, FLOWERING LOCUS T, and LEAFY orthologs throughout the family support that homology. The Yangzhou study now supplies a quantitative, node-by-node account of how that shared developmental potential is partitioned within a single plant, showing that the fate of each primordium is written in the language of hormone ratios and read out by MADS-box transcription factors. A curling tendril on a Pinot Noir vine, in this light, is not a failed flower but an alternative interpretation of the same instructions, and researchers are learning to read, and perhaps one day to rewrite, the grammar behind that choice.

Subject of Research: Molecular regulation of tendril versus inflorescence development in grapevine lateral shoots

Article Title: Comparative transcriptomics reveals hormone signaling and MADS-box genes in divergent development of inflorescences and tendrils in grapevine lateral shoots

Article References: Ni, Y., Bian, Y., Xie, Z., & Li, Y. (2026). Comparative transcriptomics reveals hormone signaling and MADS-box genes in divergent development of inflorescences and tendrils in grapevine lateral shoots. Plant Cell Reports, 45(9), Article 270. https://doi.org/10.1007/s00299-026-03957-9

Image Credits: AI Generated

DOI: 10.1007/s00299-026-03957-9

Keywords: grapevine, Vitis vinifera, tendrils, inflorescences, cytokinin, gibberellin, MADS-box, VvFUL-L, transcriptomics, hormone signaling, flowering, viticulture

Beta galactosidases belong to glycoside hydrolase family 35, a class of enzymes that cleave terminal beta-linked galactose residues from complex carbohydrates such as pectins and arabinogalactan proteins. In practical terms, these enzymes remodel the cell wall and the glycans attached to cell-surface proteins, processes that influence cell expansion, organ development, fruit softening, and even how a plant senses and responds to stress. Because the cell wall is the first line of defense against drought, salt, and temperature extremes, enzymes that modify its architecture are prime suspects in any search for stress-tolerance mechanisms. Yet before this study, the evolutionary history and stress-linked behavior of BGALs across multiple cotton genomes remained largely uncharted territory.

The research team cast a wide net across the genus Gossypium, screening the genomes of four species that represent the major cultivated and wild lineages of cotton. They identified 58 BGAL genes in Gossypium barbadense, the species behind extra-long-staple Egyptian-style cotton; 38 in Gossypium hirsutum, the upland cotton that dominates global production; 25 in Gossypium herbaceum, an Old World diploid species; and 26 in Gossypium raimondii, the D-genome diploid whose genome is a reference for the polyploid cottons. The pattern is telling: the two cultivated allotetraploid species, which carry combined A and D genomes, harbor substantially more BGAL genes than their diploid relatives, a signature of genome doubling followed by differential gene retention and loss during cotton’s evolutionary history.

To make sense of this expanded gene family, the researchers built phylogenetic trees that placed the cotton BGALs alongside their counterparts in Arabidopsis thaliana, the reference plant of molecular biology. The analysis sorted the family into eight distinct groups, each presumably reflecting a shared ancestral function and, in many cases, conserved sequence motifs in the catalytic domain. Mapping the genes onto cotton chromosomes revealed their physical distribution across the genome, and a genome-wide duplication analysis delivered one of the study’s central evolutionary findings: segmental duplication—large-scale duplication of chromosomal blocks rather than duplication of single genes—was the dominant engine driving the expansion and diversification of the BGAL family in cotton. This mode of duplication is a well-known feature of plant genome evolution, but pinning it down for this specific enzyme family clarifies how cotton acquired its enlarged BGAL repertoire.

Gene count alone says little about function, so the team turned to expression profiling. Across multiple tissues, the GhBGAL genes of upland cotton showed varied and tissue-specific activity patterns, consistent with the idea that different family members have been recruited for different developmental jobs—some likely active in rapidly expanding fibers, others in roots, leaves, or reproductive structures. More striking were the responses to abiotic stress. When cotton plants were subjected to cold, heat, salt, and drought treatments, distinct subsets of GhBGAL genes switched on or off with clear, stress-specific signatures. That differential responsiveness suggests these cell-wall-modifying enzymes are not passive bystanders during stress but active participants in the plant’s adaptation machinery, potentially reshaping wall flexibility and porosity to help tissues cope with water deficit or thermal injury.

The hormone connection adds another layer of intrigue. Promoter analysis—the computational scan of DNA sequences upstream of each gene for regulatory motifs—revealed that most GhBGAL genes carry gibberellin-responsive cis-elements, the short DNA sequences that hormone-activated transcription factors recognize. Gibberellins are the hormones that drive stem elongation, seed germination, and, critically for cotton, fiber development. To test whether the promoter evidence translated into real biology, the researchers performed quantitative real-time PCR, a laboratory technique that measures gene expression with high sensitivity. The results showed that GhBGAL expression responded rapidly to gibberellin treatment, indicating that the BGAL family may operate in coordination with GA signaling to regulate cotton growth and development. In other words, the same genes that help cotton survive stress may also be wired into the hormone pathways that determine how long and strong its fibers grow.

Why does this matter beyond the laboratory? Cotton breeding has long focused on fiber quality and yield, but climate volatility is pushing tolerance traits to the top of the priority list. The systematic catalogue produced by this study gives geneticists a ranked set of candidates: genes that are stress-inducible, hormone-responsive, and evolutionarily conserved are exactly the kind of targets that can be validated by knockout or overexpression experiments and eventually moved into breeding programs through marker-assisted selection or genome editing. Because the study spans four Gossypium species, it also illuminates which BGAL copies were retained or lost after polyploidization—information that helps breeders understand whether a tolerance trait in one species might be transferable to another.

The study also exemplifies a broader trend in plant genomics: the move from single-gene curiosity to family-wide, cross-species systematic analysis. By combining phylogenetics, chromosomal mapping, duplication analysis, expression atlases, promoter mining, and experimental qRT-PCR validation in a single framework, the researchers built a multi-layered evidence base rather than a one-dimensional gene list. This kind of integrative approach is becoming the standard for gene family studies, and it dramatically shortens the path from genome sequence to functional hypothesis. For BGALs, whose roles span cell wall biochemistry, development, and stress physiology, that path is now clearly signposted.

Open questions remain. Expression data and promoter motifs are strong circumstantial evidence, but they do not prove causation; follow-up work will need to demonstrate directly that specific GhBGAL enzymes alter cell wall composition under stress and that this alteration improves tolerance. It is also not yet clear how gibberellin signaling mechanistically controls BGAL transcription—which transcription factors bind those cis-elements, and under what developmental or environmental conditions. Still, the study’s conclusions are measured and grounded in its data: the systematic characterization of cotton BGALs reveals their evolutionary and functional landscape and delivers a set of key candidate genes for dissecting stress tolerance mechanisms and accelerating the genetic improvement of cotton. For a crop grown on tens of millions of hectares and facing a warming, salinizing world, that is a contribution with real-world stakes.

The research, funded by China’s National Key R&D Program and the Tarim University President’s Fund, was published as an open-access article in BMC Genomics, making the full gene catalogue and expression datasets available to cotton researchers worldwide. As extreme weather tightens its grip on agricultural regions from Xinjiang to the Texas High Plains, studies like this one—quietly cataloguing the molecular toolkit that lets a plant bend without breaking—are laying the groundwork for the resilient crop varieties of the coming decades.

Subject of Research: Evolution and stress-responsive expression of the beta galactosidase gene family in Gossypium cotton species

Article Title: Systematic analysis of cotton beta galactosidases and their expression profiles under abiotic stresses and gibberellin treatment

Article References: Guo, C., Guo, W., Ma, S., Zhao, G., Li, L., Hu, Q., Liang, X., Sun, J., & Chen, G. (2026). Systematic analysis of cotton beta galactosidases and their expression profiles under abiotic stresses and gibberellin treatment. BMC Genomics. https://doi.org/10.1186/s12864-026-13327-0

Image Credits: AI Generated

DOI: 10.1186/s12864-026-13327-0

Keywords: cotton, Gossypium, beta galactosidases, BGAL, gene family, abiotic stress, gibberellin, phylogenetic analysis, segmental duplication, cell wall, qRT-PCR, BMC Genomics

Sainfoin, scientifically known as Onobrychis viciifolia, is distinguished by its high concentration of condensed tannins throughout all growth stages. These compounds bind to soluble proteins in the rumen of grazing animals, precipitating them into stable foam that prevents the rapid gas expansion responsible for bloat. While this trait offers significant agricultural advantages, the molecular mechanisms governing the plant’s growth and stress responses have remained less understood compared to major cereal crops. The GID1 gene family, which encodes receptors for the plant hormone gibberellin, plays a central role in coordinating growth, development, and responses to environmental stimuli, making it a prime candidate for investigating the regulatory networks in sainfoin.

The study began with the identification of six GID1 genes, designated OvGID1, from the sainfoin genome. Physicochemical analysis revealed notable variations among these proteins, with molecular weights ranging from 38.93 to 39.55 kDa and isoelectric points spanning from 6.51 to 8.37. These differences in basic protein properties suggest potential functional diversification within the family. Furthermore, the analysis of hydrophobicity profiles indicated distinct structural characteristics that may influence protein stability and interaction with other signaling components in the gibberellin pathway.

Phylogenetic analysis classified the six identified genes into three distinct subfamilies, reflecting evolutionary divergence within the GID1 family. The genomic distribution of these genes was uneven, with the six members located across five different chromosomes. This non-random distribution suggests that the genes may have undergone specific evolutionary pressures or chromosomal rearrangements that shaped their current genomic architecture. Understanding the evolutionary history of these genes provides context for their functional roles and potential interactions with other components of the gibberellin signaling network.

To explore the regulatory potential of these genes, the researchers analyzed the promoter regions for cis-acting elements. The analysis detected numerous motifs associated with abiotic stress responses, including LTR and MBS elements, as well as hormone regulation motifs such as ABRE and GARE-motif. The presence of these regulatory sequences indicates that the OvGID1 genes are likely responsive to various environmental cues and hormonal signals. This regulatory landscape suggests that the GID1 family in sainfoin is poised to integrate multiple signaling pathways, allowing the plant to fine-tune its growth and development in response to changing conditions.

Expression analysis under abiotic stress conditions revealed specific responses for certain gene members. The OvGID1B2 gene was significantly upregulated under drought conditions, suggesting a potential role in water stress tolerance. Additionally, both OvGID1B2 and OvGID1C2 showed significant upregulation 48 hours after low-temperature treatment. These findings indicate that specific GID1 genes may be involved in the plant’s adaptive responses to environmental stresses, potentially linking gibberellin signaling to stress tolerance mechanisms. The differential expression patterns highlight the functional specialization of individual genes within the family.

The study also examined the expression of the six OvGID1 genes during seed germination, a critical phase for plant establishment. The researchers tracked gene expression across four distinct germination stages: the dry seed stage, imbibition stage, split stage, and radicle emergence stage. Treatment with gibberellin 3 (GA3) demonstrated dynamic expression patterns for all six genes throughout these stages. The varying expression levels at different germination phases suggest that the GID1 family plays a coordinated role in regulating the transition from seed dormancy to active growth. This dynamic regulation is essential for ensuring proper timing of germination in response to environmental cues.

The integration of genome-wide identification with expression analysis provides a robust theoretical foundation for understanding the evolutionary mechanisms of the GID1 family in sainfoin. The findings elucidate the molecular networks involved in gibberellin-regulated seed germination and stress responses, offering new insights into the genetic basis of plant adaptation. By characterizing the structural and functional properties of these genes, the study contributes to the broader understanding of how leguminous plants manage growth and environmental interactions. This knowledge is particularly relevant for improving forage crops that are exposed to variable environmental conditions.

The research was supported by the National Natural Science Foundation of China and other national and provincial initiatives, underscoring the importance of fundamental plant biology research in agricultural science. The authors, including Yanyan Luo, Jiao Cheng, Yuheng Yao, and Lili Nan, are affiliated with the Key Laboratory of Grassland Ecosystem and the Pratacultural College at Gansu Agricultural University. Their work represents a significant step forward in the genomic characterization of sainfoin, a crop that holds promise for sustainable livestock feeding systems. The open-access nature of the publication ensures that these findings are widely available to the scientific community, facilitating further research and potential applications in crop improvement.

As climate change and environmental stresses continue to impact agricultural systems, understanding the genetic basis of plant resilience becomes increasingly important. The identification and characterization of the GID1 gene family in sainfoin provide a valuable resource for future studies aimed at enhancing crop performance under adverse conditions. The detailed analysis of gene expression during germination and stress responses offers a blueprint for investigating similar pathways in other leguminous species. This study not only advances our knowledge of plant molecular biology but also has practical implications for the development of more resilient forage crops, contributing to food security and sustainable agriculture.

Subject of Research: Genome-wide identification and expression analysis of GID1 genes in sainfoin

Article Title: Genome-wide identification of the GID1 genes family and expression analysis during seed germination in sainfoin (Onobrychis viciifolia)

Article References: Luo, Y., Cheng, J., Yao, Y., & Nan, L. (2026). Genome-wide identification of the GID1 genes family and expression analysis during seed germination in sainfoin (Onobrychis viciifolia). BMC Plant Biology. https://doi.org/10.1186/s12870-026-10045-3

Image Credits: AI Generated

DOI: 10.1186/s12870-026-10045-3

Keywords: sainfoin, GID1, gibberellin, seed germination, plant genetics, abiotic stress, legume, gene expression, phylogenetics, BMC Plant Biology, Genome-wide, identification

The YABBY family is one of botany’s classic shape-regulating gene groups. First characterized in the laboratory weed Arabidopsis thaliana, YABBY transcription factors are DNA-binding proteins that switch other genes on or off, and they are famous for their role in defining the identity and polarity of lateral organs such as leaves, floral organs and fruits. In essence, they help a plant decide how a leaf or a fruit should grow along its length versus its width. Because fruit shape is a major determinant of yield, handling quality and market value in cucurbit crops, understanding which YABBY genes are active during fruit development in wax gourd could eventually give breeders a molecular handle on one of the crop’s most economically visible traits.

The researchers began with a systematic sweep of the wax gourd genome. Using bioinformatic screening against known YABBY sequences from Arabidopsis and other cucurbits, they identified eight BhYAB genes, which fell neatly into the five subfamilies typical of flowering plants: YAB1, YAB2, YAB3, YAB5 and CRC-like. Phylogenetic trees built from the protein sequences showed that each BhYAB gene sat closest to its homologs in Arabidopsis and related cucurbit species, indicating that the family has been conserved through the evolutionary history of these lineages rather than expanded or pruned in wax gourd specifically. That conservation is itself informative, because it suggests the core developmental functions of the family are likely shared across species, making cross-species experiments a reasonable first probe of function.

A closer look at gene architecture reinforced this picture of conservation. The eight genes shared highly similar exon-intron structures, and their proteins carried the same conserved motifs, including the zinc-finger-like N-terminal region and the characteristic YABBY domain that defines the family. When the team examined the promoter regions upstream of each gene, they found a rich assortment of hormone-responsive elements, including binding sites linked to auxin, gibberellin, abscisic acid and methyl jasmonate signaling. This detail matters because plant organ shape is heavily modulated by hormone pathways, and the presence of these regulatory elements hints that BhYAB genes may act as intersection points where developmental identity meets hormonal control.

With the family catalogued, the next challenge was deciding which member to study in depth. The team turned to transcriptome data, measuring gene activity as fragments per kilobase of transcript per million mapped reads across different tissues and fruit developmental stages. One gene stood out: BhYAB2 showed the most pronounced fruit-specific expression during early fruit development, the critical window when a young ovary is expanding rapidly after pollination. Quantitative reverse transcription PCR, a sensitive laboratory technique that amplifies and measures specific RNA transcripts, confirmed the transcriptome pattern, showing that BhYAB2 activity peaked in the days following pollination. This temporal signature made BhYAB2 the natural candidate for functional testing.

Before any functional experiment, the researchers confirmed where the protein operates inside the cell. Transcription factors must physically enter the nucleus to bind DNA, and BhYAB2 passed this test cleanly. Fusion studies with fluorescent reporter proteins showed that BhYAB2 localizes to the nucleus, consistent with its predicted nuclear localization signal and with its presumed role as a direct regulator of gene expression rather than an indirect player in the cytoplasm.

The decisive experiment came from moving BhYAB2 into Arabidopsis, the workhorse of plant genetics. The team created overexpression lines in which BhYAB2 was driven by the strong 35S promoter, forcing the gene to be active throughout the plant. The results were striking and anatomically specific. Overexpression lines produced siliques, the elongated seed pods of Arabidopsis, that were shorter and wider than those of wild-type plants. Rosette leaves showed the opposite dimensional shift, becoming longer relative to their width, with a higher length-to-width ratio. Taken together, the authors interpret these phenotypes as evidence that BhYAB2 may restrain longitudinal elongation while promoting lateral expansion of lateral organs, effectively reprogramming the growth axes of the tissues where it is active. The fact that leaves and fruits responded differently underscores how context-dependent these transcription factors can be, with the same gene producing divergent geometric outcomes depending on the organ and developmental program it enters.

To connect these visible shape changes to underlying biochemistry, the researchers examined gibberellin, the plant hormone class most directly responsible for driving cell elongation. In the siliques of BhYAB2 overexpression lines, three key gibberellin biosynthesis genes, AtGA20ox1, AtGA20ox2 and AtGA3ox1, were down-regulated. These enzymes catalyze essential steps in the production of active gibberellins, so their reduced expression is consistent with a model in which BhYAB2 dampens gibberellin biosynthesis, thereby limiting the hormone-fueled elongation that normally lengthens the organ. The authors are careful with their language here, describing this as a potential repressive effect rather than a proven causal chain, but the correlation between reduced gibberellin pathway activity and the shorter, wider organ phenotype provides a plausible mechanistic thread linking gene to geometry.

The study’s conclusions come with appropriate scientific caution. Because the functional work was performed in Arabidopsis rather than in wax gourd itself, BhYAB2 is best described as a candidate regulator of organ shape whose endogenous role in its native crop remains to be verified. The gold standard confirmation would involve knocking out or editing BhYAB2 in wax gourd and observing whether fruit dimensions change accordingly, an experiment the authors flag as the logical next step. Supplementary data from the paper, including stem measurements and expression profiles across two inbred wax gourd lines, suggest the team is already building the foundation for such validation. Still, even at the candidate stage, the work delivers real value: a complete annotated inventory of the BhYAB family, expression maps that point breeders toward fruit-development genes, and a heterologous functional test that narrows the field from eight genes to one prime suspect.

For the broader agricultural community, the implications extend beyond one melon. Wax gourd is an increasingly important crop in tropical and subtropical agriculture, and fruit shape traits in cucurbits are classic targets for both conventional breeding and gene editing. If BhYAB2 or its relatives prove to control fruit proportions in the crop itself, they could join the growing toolkit of shape genes, alongside known cucurbit fruit-shape loci, that breeders manipulate to tailor produce for market preference, mechanical harvestability and packing efficiency. The study also adds to a growing appreciation that YABBY genes across the plant kingdom act as tunable dials on organ geometry, dialing elongation up or down through hormonal pathways. What began as a systematic gene census in an under-studied gourd has thus surfaced a candidate switch with the potential to reshape, quite literally, one of Asia’s most familiar vegetables.

Subject of Research: YABBY transcription factor family identification in wax gourd and functional analysis of BhYAB2 in fruit and leaf development

Article Title: Genome-wide identification of the YABBY gene family in wax gourd (Benincasa hispida) and functional analysis of BhYAB2 in fruit and leaf development

Article References: Li, D., Wang, B., Sun, P., Zhai, X., Huang, L., Jiang, B., Yan, J., & Liu, W. (2026). Genome-wide identification of the YABBY gene family in wax gourd (Benincasa hispida) and functional analysis of BhYAB2 in fruit and leaf development. BMC Plant Biology. https://doi.org/10.1186/s12870-026-10050-6

Image Credits: AI Generated

DOI: 10.1186/s12870-026-10050-6

Keywords: YABBY transcription factors, wax gourd, Benincasa hispida, BhYAB2, fruit development, leaf development, gibberellin, transcription factors, genome-wide identification, plant hormones, cucurbits, organ shape

The discovery began with a lucky accident of mutagenesis. The researchers, led by Yushan Hou, Xuejiao Kong and Junjie Le of Northeast Agricultural University in Harbin, treated seeds of MK1, a naturally cold-tolerant japonica rice line, with a chemical mutagen that scatters random mutations across the genome. Among the resulting plants, they spotted one seedling that had lost MK1’s prized cold tolerance, wilting under chilling conditions that its parent shrugged off. They named this mutant cs1, for cold-sensitive. Genetic crosses revealed that the vulnerable phenotype was controlled by a single recessive nuclear gene, meaning one broken gene was enough to strip away the tolerance.

To find that gene, the team turned to MutMap, an elegant sequencing strategy that compares the genomes of mutant and parent to locate the causal mutation quickly. The mapping converged on a region of chromosome 9 containing OsERF5, which belongs to the large AP2/ERF family of transcription factors. These proteins bind specific DNA sequences and switch suites of target genes on or off, and in rice they have repeatedly surfaced as players in stress responses to drought, salt, heat and cold. Within OsERF5, the mutant carried a single nonsynonymous SNP in the AP2 domain, the part of the protein that grips DNA. That one-letter change in the genetic code swapped an alanine for a serine, altering the protein’s architecture precisely where it needed to function.

Expression patterns added weight to the suspicion that OsERF5 matters under stress. The gene is broadly active across the plant, but its activity surges in response to cold, salinity, osmotic stress and gibberellin, a plant hormone better known for driving stem elongation and germination. That gibberellin responsiveness turned out to be a crucial clue, hinting that OsERF5 sits at a junction between hormone signalling and the plant’s chemical armour against cold. The researchers then ran the decisive functional tests: knocking OsERF5 out made seedlings more sensitive to chilling, while overexpressing the gene or restoring a functional copy in the mutant enhanced tolerance. The results confirmed that OsERF5 is a genuine positive regulator of cold tolerance at the seedling stage, not a bystander.

How does a single transcription factor protect a seedling from cold? The answer lies in the chemistry of stress. When plants are chilled, their photosynthetic machinery and metabolism leak electrons, generating reactive oxygen species such as hydrogen peroxide. In modest amounts these molecules act as signals, but when they accumulate they oxidise membranes and proteins, causing cellular damage. Malondialdehyde, or MDA, is a classic fingerprint of that membrane damage. The team’s physiological analyses showed that plants with functional OsERF5 accumulated less hydrogen peroxide and less MDA under cold stress, indicating a strengthened antioxidant system that mops up reactive oxygen before it wreaks havoc. In the knockout lines, those protective responses were weakened, and the damage markers climbed.

The gibberellin connection gives this defence system an intriguing twist. Gibberellin is best known as a growth hormone, and breeders have long manipulated it, most famously in the semi-dwarf wheat and rice varieties of the Green Revolution. The new study links gibberellin signalling to reactive oxygen species homeostasis during cold stress, with OsERF5 associated with a GA-mediated antioxidant defence. In practical terms, the hormone does not merely tell the plant to grow; under chilling conditions it appears to help orchestrate the deployment of antioxidant capacity, and OsERF5 is a key intermediary in that command chain. This reframes gibberellin as part of the stress-response toolkit, not just a growth accelerator, and suggests that fine-tuning this pathway could yield seedlings that stay both vigorous and protected when temperatures plunge.

Beyond the lab bench, the study has an evolutionary story to tell. By scanning thousands of rice varieties, the researchers identified twelve haplotypes, distinct versions of the OsERF5 gene sequence carried by different accessions. One of them, Hap_I, stood out as the cold-tolerant version, and it is overwhelmingly predominant in temperate japonica rice, the subspecies grown in cooler regions of Japan, Korea, northern China and beyond. Population genetics analysis revealed that OsERF5 has undergone strong selection during rice domestication, meaning that ancient farmers and natural selection together favoured the cold-tolerant version as rice spread from its tropical origins into harsher climates. The gene thus carries the imprint of a millennia-long breeding programme conducted without anyone knowing the word genetics.

That history makes Hap_I immediately useful for modern breeders. Because the cold-tolerant haplotype already exists in cultivated germplasm, breeders can track it with DNA markers and introgress it into elite varieties that lack it, a strategy known as marker-assisted selection. This is far faster than waiting for plants to grow out under cold conditions, and it avoids dragging along unwanted traits from donor parents. For rice production in high-latitude regions such as northeastern China, where the research team is based, and in high-altitude zones where chilling nights are routine, a validated cold-tolerance haplotype is exactly the kind of resource that turns molecular knowledge into sturdier fields. The authors describe Hap_I as a valuable genetic resource for breeding cold-adapted rice, and the evidence supports that framing.

The study also slots into a rapidly growing catalogue of rice cold-tolerance genes. Earlier work identified COLD1, whose natural variation confers chilling tolerance, and more recent discoveries include COLD11, CTF1, CTB5 and CTB4a, each illuminating a different node of the cold-response network, from ion channels to flowering-stage resilience. OsERF5 adds a transcriptional regulator tied to hormone signalling and antioxidant defence, a layer that had been less well characterised at the seedling stage. Together these genes sketch a picture of cold tolerance as a distributed property, built from sensory machinery, hormonal cross-talk and enzymatic detoxification, any single component of which can be improved by breeding.

For a world where extreme weather increasingly disrupts crop production, the stakes are concrete. Cold damage at the seedling stage forces farmers to delay planting or resow, shrinking the growing season and yields in marginal regions. A gene like OsERF5, validated by knockout, overexpression and complementation, and backed by a clear haplotype signature and a plausible molecular mechanism, gives breeders a precise target rather than a statistical shadow. The work, funded by the National Natural Science Foundation of China and partner programmes, demonstrates how a chemical mutagenesis experiment in a single rice line can end up tracing the evolutionary history of a species and pointing the way to the next generation of cold-proof crops. As chilling temperatures continue to test the limits of the world’s rice paddies, the humble transcription factor on chromosome 9 may prove to be one of the quiet heroes of food security.

Subject of Research: A rice AP2/ERF transcription factor gene, OsERF5, that regulates seedling cold tolerance through gibberellin-mediated antioxidant defence

Article Title: OsERF5 enhances cold tolerance and is associated with GA‑mediated antioxidant defence in rice

Article References: Hou, Y., Kong, X., Le, J., Yang, R., Qi, N., Wang, J., Liu, H., Zheng, H., Xin, W., Zou, D., Lei, L., & Yang, L. (2026). OsERF5 enhances cold tolerance and is associated with GA‑mediated antioxidant defence in rice. Theoretical and Applied Genetics, 139(10), Article 273. https://doi.org/10.1007/s00122-026-05385-5

Image Credits: AI Generated

DOI: 10.1007/s00122-026-05385-5

Keywords: rice, cold tolerance, OsERF5, transcription factor, gibberellin, reactive oxygen species, antioxidant defence, haplotype, japonica rice, plant breeding, abiotic stress, MutMap

The study, led by researchers at the Shandong Academy of Agricultural Sciences in collaboration with the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Murdoch University and other partners, began with a de novo sequencing effort that produced ten new high-quality genome assemblies. These were combined with previously published references to create a pan-genome of fourteen genomes representing all six botanical varieties of cultivated peanut. Long-read sequencing platforms, including PacBio HiFi and Oxford Nanopore technologies, together with Hi-C scaffolding, allowed the team to resolve the peanut’s complicated tetraploid genome, which harbors two distinct subgenomes derived from the wild ancestors Arachis duranensis and Arachis ipaensis.

The resulting pan-genome cataloged a striking wealth of variation invisible to earlier single-reference analyses. The team identified tens of thousands of structural variants across the fourteen assemblies, including more than 21,000 deletions, over 21,500 insertions, hundreds of copy number variations, inversions and translocations. Presence-absence variants, large chunks of DNA found in some accessions but not others, proved especially common in intergenic regions, where they can alter gene regulation. Gene counts fluctuated widely among the genomes: the analysis distinguished a core set of roughly 48,948 genes shared by all accessions, alongside thousands of softcore, dispensable and private genes whose presence or absence correlated with measurable differences in gene expression and with pathways tied to adaptation and agronomic performance.

Armed with this graph-based reference, the researchers genotyped an unprecedented collection of 2,320 accessions drawn from global genebanks, material covering 88.03 percent of the ICRISAT core collection and 59.21 percent of the USDA core germplasm. Because reads were mapped to a pan-genome graph rather than a single reference sequence, the team could call variants with far greater accuracy, particularly in the duplicated, highly similar regions that pervade the peanut genome. Phylogenetic and population-structure analyses of the resequenced accessions recovered the major cultivar groups and traced patterns of geographic spread and gene flow, offering a detailed picture of how this crop diversified after its domestication in South America.

One of the study’s central technical achievements involved homoeologous exchanges, the swapping of chromosome segments between the A and B subgenomes of this young allopolyploid. Such exchanges create a genotyping nightmare, because sequence reads from one subgenome can be misassigned to its counterpart, distorting both variant calls and association signals. By explicitly characterizing homoeologous exchange events across the pan-genome and modeling them during genotyping, the researchers showed that these exchanges have contributed meaningfully to population divergence among peanut groups and even to the differentiation of subspecies, influencing genes such as a phytochrome A ortholog involved in photoperiod response and a DAG1-like gene tied to seed biology.

The pan-genome framework immediately paid off in gene discovery. A structural-variant genome-wide association study pinpointed a major locus for flowering pattern on chromosome 12. The team identified AhTFL1, a homolog of the TERMINAL FLOWER 1 gene family that represses flowering, as a key regulator. In an alternate allele carried by the accession Shitouqi, a 1,489-base-pair deletion disrupts the gene. Transgenic experiments in Arabidopsis confirmed that the intact peanut TFL1-like allele delays flowering and alters inflorescence architecture, while the deleted version loses that capacity, explaining differences between sequential and alternate flowering patterns that shape peanut plant habit and harvest timing.

Dwarfism, a trait of intense breeding interest because compact plants resist lodging and tolerate denser sowing, yielded a second discovery. Fine mapping in a cross between the reference cultivar Tifrunner and a dwarf accession revealed an abnormal recombination region on chromosome 02, caused in part by a balanced reciprocal translocation between chromosomes 02 and 12 present in several accessions. Within the critical interval, the researchers identified a 47.31-kilobase deletion in dwarf lines that removes a gene, Ah12g032500, implicated in gibberellin-related growth regulation. Virus-induced gene silencing of this gene in normal plants reproduced the dwarf phenotype, and biochemical assays showed altered gibberellin content, with dwarf seedlings resuming elongated growth after treatment with exogenous gibberellic acid, cementing the gene’s role in a pathway reminiscent of the Green Revolution dwarfing genes of rice and wheat.

Beyond single genes, the pan-genome enabled association mapping across a broad spectrum of agronomic traits, linking structural variation to characteristics ranging from pod architecture to plant height. The team then translated this knowledge directly into breeding practice. By integrating superior haplotypes identified through the pan-genome with elite germplasm resources, they developed high-yield dwarf peanut lines, demonstrating that the resource is not merely a catalog but a working platform for cultivar improvement. For a crop central to food security and nutrition across Asia and Africa, where peanuts supply protein and oil to hundreds of millions of people, the ability to combine dwarfing architecture with high pod yield could reshape on-farm performance.

The study aligns with a broader movement in plant science away from single reference genomes and toward pan-genomes that capture the full spectrum of diversity within a species. Comparable efforts in barley, wheat, rapeseed and soybean have repeatedly revealed that structural variation, not just single-letter DNA changes, drives trait differences of agricultural importance. Peanut’s pan-genome now places this orphaned-genome crop in that company, and the scale of the resequencing panel ensures that breeders worldwide can find genetic material close to their own local varieties and mine it for favorable alleles.

All of the underlying data have been released to the community. The ten new assemblies and their sequencing reads are deposited in public archives at the National Genomics Data Center and NCBI, along with the resequencing data for the 2,320 accessions, and the complete analysis code is available on GitHub and Zenodo. That openness matters: genomics-assisted breeding in peanut has historically lagged behind maize, rice and wheat, partly because resource-rich and resource-poor breeding programs diverged in their access to data. By publishing a graph pan-genome, thousands of genotyped accessions, cloned genes for flowering and dwarfism, and ready-made high-yield dwarf lines, the consortium has effectively handed the global peanut community a new starting point for the next generation of cultivars, one in which hidden structural variation becomes a resource rather than a blind spot.

Subject of Research: A graph-based pan-genome and large-scale resequencing of cultivated peanut revealing structural variation and breeding-relevant genes

Article Title: Pan-genome-based resequencing of 2,320 accessions reveals structural variations and accelerates breeding advances in cultivated peanut

Article References: Liu, Y., Li, W., Li, R., Pandey, M. K., Bai, B., Han, Y., Tang, G., Zhang, L., Chitkineni, A., Li, Y., Li, L., Li, S., Garg, V., Du, F., Cui, F., He, L., Shan, L., Xu, F., Xu, P., … Wan, S. (2026). Pan-genome-based resequencing of 2,320 accessions reveals structural variations and accelerates breeding advances in cultivated peanut. Nature Genetics, 58(10), 2706-2716. https://doi.org/10.1038/s41588-026-02765-x

Image Credits: AI Generated

DOI: 10.1038/s41588-026-02765-x

Keywords: peanut, pan-genome, structural variation, homoeologous exchange, Arachis hypogaea, genomics, plant breeding, dwarfism, flowering, AhTFL1, gibberellin, germplasm

The new study, published in The Crop Journal by the university’s Rapeseed Cultivation Physiology Team, demonstrates that crowded growing conditions trigger an early surge in gibberellin activity, the plant hormone that drives stem elongation. This premature activation pushes stems to stretch rapidly before the structural scaffolding of the plant, built from cellulose and lignin in the cell walls, has had a chance to catch up. The consequence is a temporal mismatch: elongation races ahead while reinforcement lags behind, leaving mature plants with thinner, weaker stems that bend and break more easily under their own weight or under wind and rain.

“We found that high-density planting does not simply restrict stem development. Instead, it alters the timing of GA activation, causing stem elongation to occur ahead of structural reinforcement,” explains corresponding author Associate Professor Jing Wang. “This temporal mismatch provides new insight into why stems become weaker under high-density conditions.” The finding reframes the lodging problem in rapeseed not as a simple consequence of resource competition but as a disorder of developmental coordination, one that may be open to targeted intervention.

To reach this conclusion, the researchers conducted two-year field trials using two genetically distinct rapeseed cultivars: ZS11, a conventional variety, and HYZ50, a hybrid. Each cultivar was grown at two planting densities, a low density of 3.0 × 10⁵ plants per hectare and a high density of 6.0 × 10⁵ plants per hectare, allowing the team to isolate the effects of crowding on stem development across different genetic backgrounds. The trials tracked stem elongation throughout the growing season, with particular attention to the window from budding to initial flowering, the period during which rapeseed stems accomplish most of their vertical growth.

The measurements revealed a consistent pattern in both cultivars. Stem elongation occurred mainly between budding and initial flowering, and high-density planting amplified the contribution of this window to final plant height. In other words, crowded plants grew taller by stretching more intensively during this early phase. At the same time, the high-density plants showed reduced mechanical strength in their stems. To test whether this pattern held across a broader genetic spectrum, the team analyzed a panel of 243 rapeseed accessions. The analysis showed that a greater proportion of height gain during the budding-to-flowering stage was negatively correlated with mature stem bending strength, and this relationship was particularly pronounced under high-density conditions. Plants that shot up fastest early tended to end up with the weakest stems.

With the phenotypic pattern established, the researchers turned to the molecular mechanisms underlying it. Transcriptomic and physiological analyses of developing stems revealed that high-density conditions triggered earlier activation of gibberellin biosynthesis and signaling. The hormone surge set off rapid cell elongation, but the processes responsible for mechanical reinforcement, namely the deposition of cellulose and lignin into secondary cell walls, did not accelerate in parallel. Instead, they lagged behind, and the high-density plants ultimately accumulated less cellulose and lignin overall. The researchers also measured lower cellulose crystallinity in the high-density plants, a property closely tied to the load-bearing capacity of cell walls, and correspondingly weaker stem bending strength at maturity.

“Transcriptomic and physiological analyses showed that high density triggered earlier GA activation, followed by rapid stem elongation, whereas cellulose and lignin accumulation and mechanical reinforcement lagged behind,” says Wang. “High-density plants also showed reduced cellulose and lignin contents, lower cellulose crystallinity, and weaker stem bending strength.” Together, these results identify a specific hormonal mechanism, a premature gibberellin pulse, as the driver of the elongation-reinforcement desynchronization that undermines stem integrity in dense stands.

The mechanistic insight pointed directly at a practical test: if excess gibberellin activity is the problem, suppressing it should restore the balance between growth and reinforcement. To find out, the researchers applied two gibberellin biosynthesis inhibitors, uniconazole and DPC, under real field conditions. Uniconazole proved particularly effective. By lowering endogenous gibberellin levels, the compound restrained the excessive early elongation of stems and simultaneously promoted the accumulation of cellulose and lignin. Treated plants developed denser stem tissue and significantly improved bending strength, confirming that the hormone’s timing, not merely its presence, governs the structural quality of the stem.

Remarkably, the benefits of gibberellin regulation extended beyond lodging resistance to yield itself. Under high-density planting, uniconazole treatment increased per-plant yield by 9.4 percent in the conventional cultivar ZS11 and by 10.8 percent in the hybrid HYZ50. When scaled to yield per unit area, the gains were 7.0 percent and 6.6 percent, respectively. For a crop in which density-driven lodging has often forced growers to choose between planting densely for mechanization and planting sparsely for stability, the result suggests that chemical regulation of gibberellin dynamics could allow them to have both.

“The improvement in both stem strength and yield following GA regulation is particularly encouraging,” Wang says. “Optimizing GA dynamics during critical developmental stages may help achieve a better balance between plant architecture, lodging resistance, and yield under high-density cultivation.” The study’s implications reach beyond rapeseed. Gibberellin governs stem elongation in many cereal and oilseed crops, and the principle that elongation and cell wall reinforcement must be temporally coordinated may apply wherever high-density planting is used to push productivity. As global agriculture intensifies and mechanized harvesting becomes the norm, managing the hormonal choreography of stem development could prove as important as breeding for yield itself. For now, the Huazhong team’s work offers rapeseed growers a concrete new lever: by tempering the early gibberellin surge, they can help stems build strength before they build height, turning crowded fields from a structural liability into a productive advantage.

Subject of Research: How high-density planting disrupts the coordination between gibberellin-driven stem elongation and cell wall reinforcement in rapeseed

Article Title: Huazhong Agricultural University researchers reveal how high-density planting disrupts stem development in rapeseed

Article References: Huazhong Agricultural University researchers reveal how high-density planting disrupts stem development in rapeseed. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: rapeseed, Brassica napus, gibberellin, high-density planting, lodging resistance, stem elongation, cellulose, lignin, cell wall reinforcement, uniconazole, crop yield, plant hormone