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At least 19 recordsLinked to original sources

Integrating plant phenotypic and genotypic data in the AGENT project: a BrAPI service implementation.

MOTIVATION: The AGENT project established a network of actively cooperating European genebanks, integrating genomic and phenotypic data from accessions of wheat and barley. Due to specific storage demands for phenotypic and genotypic data, the project used separate database instances and backend technologies to manage integrated phenotypic and genotypic data. RESULTS: We discuss the challenges encountered when integrating dispersed data to serve through a single interface such as the Plant Breeding Application Programming Interface, BrAPI. We examine how the consistent mappability of genebank data to the BrAPI model can enable the implementation of effective services. The advantages of BrAPI in transparently linking distributed data entities through embedded, unique identifiers are highlighted. We present a technical solution involving a BrAPI proxy, which combines and merges separate BrAPI endpoints. Finally, we demonstrate the AGENT BrAPI implementation with an illustrative example that validates a suggested SNP for a trait from the literature by linking phenotypic, genotypic and passport data. AVAILABILITY AND IMPLEMENTATION: The BrAPI proxy implementation and documentation is available at the Python Package Index (https://pypi.org/project/brapi-proxy) and archived in Zenodo (doi: 10.5281/zenodo.19436445). SUPPLEMENTARY INFORMATION: A Jupyter Notebook file for the validation example using a marker-trait relationship found in the literature.

Phenotype

Divergent and stabilizing selection shape the phenotypic space of Arabidopsis thaliana.

Why do we observe some plant phenotypes but not others? The multivariate phenotypic space occupied by individuals or species often reveals both limits and phenotypes strikingly deviating from main syndromes. These observations are usually thought to indicate, respectively, inviable trait combinations and unique phenotypes adapted to specific environments. However, the evolutionary drivers underlying trait covariations often remain unclear. Here, we characterized the phenotypic space of Arabidopsis thaliana by comparing 713 wild accessions collected across the globe with 2,544 artificially-created recombinant individuals. This, combined with the detection of adaptive processes operating within species, allowed us to elucidate the roles of natural selection as a driver of phenotypic (co)variations within A. thaliana. We found that the phenotypic space of this species is constrained and driven by varying levels of divergent and stabilizing selection across different traits. Moreover, at the margins of the European geographic range, strong directional selection favored outlier phenotypes characterized by very late flowering and variation in a WRKY transcription factor gene. Genome analyses revealed that these extreme phenotypes may be explained by hybridization between ancestral and modern lineages of A. thaliana. Our findings demonstrate how interplays between population history and natural selection shape phenotypic diversity in a plant species.

Arabidopsis

Two Bacillus PGPB Strains in Wheat and Soybean: Wheat Growth Promotion Without Detectable Rhizosphere Microbiome Restructuring.

Plant growth-promoting bacteria (PGPB) are increasingly deployed as biofertilizers, yet the link between an inoculant's genomic potential and its realized effect on the plant is rarely assessed within an integrative framework that jointly captures the rhizosphere microbiome, plant phenotype, and strain genome. Two Bacillus strains-B. halotolerans 1453 and B. pumilus 630-were applied to wheat and soybean in a factorial pot experiment (2 strains &#xd7; 2 application methods &#xd7; 3 frequencies + control, 3-4 replicates). Rhizosphere samples (n = 67 after filtering) were profiled by 16S rRNA sequencing with PICRUSt2 functional prediction and compositional validation (Aitchison PERMANOVA, ALDEx2, ANCOM-BC2). The PGPB gene repertoire was characterized by genome mining (481 marker genes, 14 categories). Wheat phenotype (six traits) and soybean height were analyzed with models appropriate for count data (Negative Binomial and binomial GLMs) for treatment-vs.-control comparisons, and with factorial ANOVA for decomposition into main effects and interactions. Crop identity was the dominant factor shaping both microbiome structure and function (PERMANOVA R2 = 14.7% taxonomically and R2 = 7.8% functionally, both p < 0.001), with biologically meaningful taxonomic differences between wheat and soybean; strain, application count and method had no significant effect on community composition (R2 < 4% each), and co-occurrence networks showed no reliable differences between crops once read depth and sample size were controlled for. Despite this neutrality at the microbiome level, inoculation significantly increased wheat spike count (NB-GLM, all 12 treatments vs. control, padj 0.0002-0.031), ear weight, and stem count, with application count the strongest source of variability and a pronounced strain &#xd7; application count. Strain 1453 outperformed 630 in spike count (+23.1%, p = 0.012) and ear weight (+20.4%, p = 0.023); we hypothesize that this may be related to its more complete DNRA pathway (narGHI + nirB-nirD) and biocontrol genes (bacE, srfAA). Strain 630 produced a less pronounced effect than strain 1453 but was subject to smaller fluctuations across replicates (CV &#x2248; 16-21% vs. &#x2248;24-26% for 1453), which may reflect better resilience to environmental fluctuations, possibly due to its confirmed rsbV/rsbW stress-tolerance regulon. Rhizosphere microbiome composition differed clearly by crop (wheat vs. soybean) but showed no detectable response to strain, application method, or application count. Despite this lack of a microbiome signal, inoculation significantly increased wheat spike count and ear weight, with the magnitude and stability of this effect differing by strain. We hypothesize that this strain-dependent difference relates to underlying genomic differences-particularly in nitrogen metabolism (DNRA pathway) and stress-tolerance genes-though this link has not been tested directly and remains a hypothesis for future work.

Triticum

Breaking the reproducibility barrier with standardized protocols for plant-microbiome research.

Inter-laboratory replicability is crucial yet challenging in microbiome research. Leveraging microbiomes to promote soil health and plant growth requires understanding underlying molecular mechanisms using reproducible experimental systems. In a global collaborative effort involving five laboratories, we aimed to help advance reproducibility in microbiome studies by testing our ability to replicate synthetic community assembly experiments. Our study compared fabricated ecosystems constructed using two different synthetic bacterial communities, the model grass Brachypodium distachyon, and sterile EcoFAB 2.0 devices. All participating laboratories observed consistent inoculum-dependent changes in plant phenotype, root exudate composition, and final bacterial community structure, where Paraburkholderia sp. OAS925 could dramatically shift microbiome composition. Comparative genomics and exudate utilization linked the pH-dependent colonization ability of Paraburkholderia, which was further confirmed with motility assays. The study provides detailed protocols, benchmarking datasets, and best practices to help advance replicable science and inform future multi-laboratory reproducibility studies.

Plants

Tm-1 back in business: an allele from Solanum pennellii accessions plays a major role in ToBRFV resistance.

The Tm-1 allele from&#xa0;Solanum pennellii&#xa0;accessions together with an additional, likely recessive, locus are required for&#xa0;complete&#xa0;ToBRFV resistance. The Tobamovirus Tomato Brown Rugose Fruit Virus (ToBRFV) poses a significant threat to global tomato production. ToBRFV is a mechanically transmitted virus containing a single-stranded positive sense RNA genome. Disease symptoms include brown, rough patches on fruit surfaces, leaf mosaicism and shape abnormalities, and, in advanced stages, total collapse of infected plants. ToBRFV was first detected in the Middle East in 2014 and has rapidly spread to multiple countries across Asia, Europe, and America. In recent years, numerous studies have focused on the identification of ToBRFV resistance traits that are suitable for tomato breeding programs. In this study, we identified five ToBRFV-resistant accessions of Solanum pennellii, a wild relative of cultivated tomato. We confirmed that the major gene controlling this resistance trait is the S. pennellii allele of Tm-1. Tm-1 was previously identified in S. habrochaites as a semidominant Tomato Mosaic Virus (ToMV) resistance gene. Our results show that full resistance to ToBRFV disease requires an additional undescribed locus. These results show the potential of S. pennellii as a novel source of resistance against ToBRFV.

Disease Resistance

Developmental roles of LSD1/KDM1A-like (LDL) proteins in plants.

LYSINE-SPECIFIC DEMETHYLASE 1-like (LDL) proteins are conserved FAD-dependent amine oxidases that serve as pivotal regulators in plants. While animal systems typically rely on a single LSD1/KDM1A enzyme, the Arabidopsis thaliana genome encodes an expanded family of LDL homologues (FLD, LDL1, LDL2, and LDL3), resulting in substantial subfunctionalization and specialized recruitment mechanisms. This review explores the diverse developmental roles of plant LDLs, ranging from flowering time and circadian clock regulation to heterochromatin maintenance and epigenetic regulation. We discuss the redundant roles of FLD, LDL1, and LDL2 in repressing the floral repressor FLC and their nonredundant specialized function within the CCA1/LHY-TOC1 circadian feedback loop. A central focus of our review is the emerging mechanism of transcription-coupled demethylation, in which LDLs associate with the phosphorylated C-terminal domain of RNA polymerase II to modify chromatin cotranscriptionally within gene bodies. By integrating findings from Arabidopsis thaliana and crops such as tomato and soybean, we illustrate how the diversified LDL-mediated regulatory toolkit facilitates precise, gene-specific regulation. Ultimately, the LDL family represents a cornerstone of the sophisticated epigenetic strategies that regulate plant phenotypic plasticity in response to developmental and environmental cues.

Circadian clock

Parent-of-origin effects on allelic expression bias in interspecific poplar hybrids.

In hybrid plants, phenotypic outcomes are governed by interactions between the two parental genomes. However, the mechanisms underlying the interplay of divergent regulatory networks from these genomes remain poorly understood. In this study, we compared gene-level and allele-specific expression patterns, as well as differentially enriched pathways between F&#x2081; and complex backcross (CBC) lines derived from a natural interspecific hybrid population of Populus fremontii (Pf) and P. angustifolia (Pa). Metabolic differences between Pf and Pa which exhibit low and high levels respectively of phenylpropanoid-derived condensed tannins were leveraged. Using individualized transcriptome references, differential expression and clustering analyses revealed CBC-biased and F&#x2081;-biased expression for genes involved in phenylpropanoid metabolism and photosynthesis, respectively. Biased expression of these genes at the allele level was also observed in F1. At the whole-transcriptome level, Pa-biased genes predominated in F&#x2081; hybrids, and Pa alleles displayed more conserved expression patterns than Pf alleles across examined samples. Further analyses indicated that allelic expression bias was significantly associated with parental origin, which could be driven by sequence variations in cis-regulatory elements and differences in CpG island length. Our findings demonstrate strong parent-of-origin effects on divergent regulatory networks governing gene expression in poplar hybrids and provide clues for strategic parental selection tailored to specific metabolic pathways of interest.

cis-regulation

Identification and fine mapping of a locus controlling multi-main-stem trait in Brassica napus.

BACKGROUND: The main stem is a crucial component determining individual plant yield in rapeseed (Brassica napus). However, the genetic and developmental basis underlying the multi-main-stem trait remains largely unclear. RESULTS: In this study, we identified a multi-main-stem mutant, mms1, which exhibited a significantly increased silique number per plant and abnormal shoot apical meristem (SAM) development. Genetic analysis demonstrated that the multi-main-stem trait was controlled by a recessive gene. Using bulked segregant analysis combined with a Brassica napus 50&#xa0;K SNP array and map-based cloning, the locus was mapped to a 340-kb interval on chromosome A09 of the ZS11 reference genome and was designated BnaA09.MMS1. Candidate gene analysis revealed that BnaA09G0254500ZS, which harbors sequence variations in both the promoter and coding regions and shows significantly increased expression in the mutant, was the most likely candidate gene. In addition, phytohormone analysis revealed reduced auxin accumulation in mutant SAMs, together with transcriptomic changes in genes associated with the CLAVATA3 (CLV3)-WUSCHEL (WUS) feedback loop. CONCLUSIONS: These findings provide an important foundation for elucidating the genetic basis of the multi-main-stem trait and offer a valuable genetic resource for rapeseed improvement.

Brassica napus

Current landscape of Cys-OxiPTMs in plants: from hormone signaling to phenotypic control and their potential in sustainable agriculture.

The integration of environmental and developmental cues into coherent physiological responses is fundamental to plant survival. Reactive oxygen, nitrogen, and sulfur species (ROS/RNS/RSS) are now recognized as essential signaling molecules, not merely cytotoxic byproducts. Their specificity is largely achieved through reversible, site-specific cysteine oxidative post-translational modifications (Cys-OxiPTMs), which constitute a dynamic and sophisticated "redox code". This review provides a systematic synthesis of the current landscape of Cys-OxiPTMs in plants, bridging chemistry, hormone biology, agronomy, detection, and engineering. The chemical and enzymatic basis of major Cys-OxiPTMs is detailed, along with a discussion of how their spatiotemporal interplay orchestrates signaling specificity. A critical examination is then presented on how these modifications decode and integrate plant hormone signaling networks to regulate key agronomic traits. Cutting-edge proteomic technologies that have revolutionized the identification of redox-sensitive cysteines are also evaluated. Finally, forward-looking strategies to "write" the redox code are explored. By moving the field from descriptive cataloging to predictive "redox breeding", this review establishes a foundational framework for manipulating Cys-OxiPTMs to develop climate-resilient, high-yielding crops for sustainable agriculture.

Agronomic traits

Fine mapping of the dominant female sterility gene and novel model of hybrid seed production in cabbage (Brassica oleracea L. var. capitata).

Hybrid breeding based on male sterility requires the removal of male parents, which is time- and labor-intensive; however, the use of female sterile male parent can solve this problem. In the offspring of distant hybridization between Brassica oleracea and Brassica napus, we obtained a mutant, 5GH12-279, which not only fails to generate gynoecium (thereby causing female sterility) but also has serrated leaves that could be used as a phenotypic marker in seedling screening. Genetic analysis revealed that this trait was controlled by a single dominant gene. Further analysis revealed that Bo2g005230, an orthologous gene of LATE MERISTEM IDENTITY1 (LMI1) in Arabidopsis, was predicted as the candidate gene and was renamed BoLMI1c. Sequence analysis revealed that homoeologous exchange (HE) occurred within the BoLMI1c gene body of 5GH12-279, which resulted in the generation of a novel fusion transcript. Two pairs of primers, N5230-1F/1R and N5230-2F/2R, were designed and successfully used for the identification of different genotypes of BoLMI1c. Transcriptome analysis revealed that BoLMI1c orchestrates the expression of several related biological processes and transcription factors. Furthermore, we found that self-pollination with mason bees produced no seeds in 5GH12-279, whereas the near-isogenic line 5GH12-170 produced seeds that were normal. Therefore, a new labor-saving hybrid seed production system with no need to remove the male parents, which is especially important for mechanized harvest in the future, has been proposed. Our study provides a valuable source of dominant female sterility and suggests the potential utilization of the female sterile line in hybrid breeding for mechanized harvest.

Plant Infertility

The genetic basis of chloride exclusion in grapevines.

Mediterranean regions are among the most important areas for global grape production, characterized by dry climates and frequent challenges associated with soil salinity. In these environments, chloride toxicity is a major factor limiting vine growth and fruit quality. Despite the critical role of chloride exclusion in salinity tolerance, the genetic mechanisms underlying this trait remain poorly understood. In this study, we analyzed natural variation in chloride exclusion using a diverse panel of 335 accessions representing 18 wild and cultivated Vitis species. This panel, comprising accessions from the southwestern United States and Mexico, captures a broad range of evolutionary adaptations to abiotic stress and provides a valuable genetic resource for breeding efforts aimed at introducing novel traits. Using genome-wide association and quantitative trait loci (QTL) mapping, we identified a major QTL on chromosome 8, now designated qClEx8.1, containing candidate genes encoding cation/H&#x207a; exchangers (CHXs), which are involved in ion transport and homeostasis. To validate these findings, we analyzed a mapping population derived from Vitis acerifolia longii 9018 and the commercial rootstock GRN3, confirming the chromosome 8 locus as a major determinant of chloride exclusion. Structural variant analysis revealed nonsynonymous substitutions within CHX genes that may influence protein function and salinity tolerance. Additionally, we discovered a novel QTL on chromosome 19 enriched with G-type lectin S-receptor-like serine/threonine-protein kinases, known regulators of stress signaling. By integrating phenotypic and genomic data across a diverse Vitis collection, this study advances our understanding of the genetic architecture underlying chloride exclusion and highlights candidate genes for breeding salt-tolerant rootstocks.

Vitis

Quantitative Profiling of Histone Variants and Posttranslational Modifications by Tandem Mass Spectrometry in Arabidopsis.

Histone dynamics constitute an important layer of gene regulations associated with development and growth in multicellular eukaryotes. They also stand as key determinants of plant responses to environmental changes. Histone dynamics include the exchange of histone variants as well as post-translational modifications of their amino acid residues (such as acetylation and mono/di/trimethylation), commonly referred to as histone marks. Investigating histone dynamics with a focus on combinatorial changes occurring at their residues will greatly help unravel how plants achieve phenotypic plasticity.Mass spectrometry (MS) analysis offers unequaled resolution of the abundance of histone variants and of their marks. Indeed, relative to other techniques such as western blot or genome-wide profiling, this powerful technique allows quantifying the relative abundances of histone forms, as well as revealing coexisting marks on the same histone molecule. Yet, while MS-based histone analysis has proven efficient in several animals and other model organisms, this method stands out as more challenging in plants. One major challenge is the isolation of sufficient amounts of pure, high-quality histones, likely rendered difficult by the presence of the cell wall, for sufficiently deep and resolutive identification of histone species.In this chapter, we describe a straightforward MS-based proteomic method, implemented to characterize histone marks from Arabidopsis thaliana seedling tissues and cell culture suspensions. After acid extraction of histones, in vitro propionylation of free lysine residues, and digestion with trypsin, a treatment at highly basic pH allows obtaining sharp spectral signals of biologically relevant histone peptide forms.The method workflow described here shall be used to measure changes in histone marks between Arabidopsis thaliana genotypes, along developmental time-courses, or upon various stresses and treatments.

Histones

Combining ability and gene action for grain yield and biofortification traits in pearl millet [Pennisetum glaucum (L.) R. Br.]: implications for breeding high-yielding biofortified hybrids in arid regions.

Hybrid RIB-9184 &#xd7; RIB-15131 combines high yield (18.84 g plant&#x207b;&#xb9;) with iron (46.16 mg kg&#x207b;&#xb9;), zinc (38.86 mg kg&#x207b;&#xb9;), and protein (11.91%); Fe-Zn correlation (rg = 0.82) permits simultaneous biofortification. Pearl millet [Pennisetum glaucum (L.) R. Br., syn. Cenchrus americanus (L.) Morrone] is a climate-resilient cereal with inherently high micronutrient levels, making it a priority crop for biofortification. Understanding gene action for yield and nutritional traits is essential for designing effective breeding strategies. Ten diverse inbred lines were crossed in a half-diallel design (Griffing's Method 2, Model 1), and the 55 entries (45 F1 hybrids + 10 parents) were evaluated across two sowing-date environments in a randomised complete block design with three replications at Jaipur, Rajasthan, India. Biofortification traits (Fe, Zn, protein) showed predominantly additive gene action (Baker's ratio 0.71-0.91) with high heritability (0.90-0.94). G&#xd7;E interaction was significant for Fe and Zn but genotypic variance was substantially larger, maintaining high heritability; protein showed no G&#xd7;E interaction. Grain yield was governed largely by non-additive effects (Baker's ratio 0.54) with significant G&#xd7;E interaction, favouring hybrid breeding. Among parents, RIB-9205 had the highest GCA for Fe (6.65, P&#x2009;<&#x2009;0.001), RIB-9184 for Zn (3.85, P&#x2009;<&#x2009;0.001) and protein (0.78, P&#x2009;<&#x2009;0.001), and RIB-9185 was a balanced combiner for yield (1.39, P&#x2009;<&#x2009;0.001) and micronutrients. The hybrid RIB-9184 &#xd7; RIB-15131 ranked first across all five weighting schemes of the multi-trait performance index (1.31), combining grain yield of 18.84&#xa0;g plant&#x207b;1 with Fe of 46.16&#xa0;mg&#xa0;kg&#x207b;1, Zn of 38.86&#xa0;mg&#xa0;kg&#x207b;1, and protein of 11.91%. The strong Fe-Zn correlation (rg = 0.82, P&#x2009;<&#x2009;0.01) permits simultaneous micronutrient improvement. An integrated approach combining hybrid development for yield with population improvement for micronutrient density is recommended for biofortified pearl millet cultivars in arid regions.

Pennisetum

Common gardens reveal genomic susceptibility and vulnerability to climate change in Eucalyptus.

Accelerated global climate change and increased species introduction across international scales have raised concerns about the potential for trees to experience maladaptation or lagging adaptation in response to these environmental shifts. However, our knowledge regarding the relationship between the genomic metrics used to predict maladaptation and actual fitness proxies in trees remains limited. Here, we present a population genomic analysis of 295 families from 28 provenances of Eucalyptus pellita, a widely cultivated fast-growing tree species, and conducted two common garden experiments. Genomic susceptibility encompassing individual heterozygosity (H), genomic inbreeding (FROH), and genomic load (inferred from deleterious mutations) exhibited distinct geographic patterns, shedding light on the origin and evolutionary history of E. pellita. The genetic basis of local adaptation was elucidated through genotype-environment associations and genome-wide association studies, including 198 loci associated with climate and 2388 loci regulating different traits. Furthermore, Australian provenances have higher genomic vulnerability under prospective climate alterations than Papua New Guinea and Indonesia provenances. By integrating phenotypic data across two common gardens, the relationship between leaf functional traits and predicted metrics of maladaptation was closer than growth attributes. Notably, pronounced natural selection signals linked to leaf morphogenesis have been identified by comparing two lineages spanning the oceans. This study underscores the immense potential of leveraging genomic susceptibility and genomic vulnerability to decipher the local (mal)adaptation of forest trees.

Eucalyptus

The cold case of state transition 7 (stt7) mutants of Chlamydomonas reinhardtii, solved by whole-genome sequencing.

The process of State Transitions (ST) corresponds to an STT7 kinase-driven redistribution of the transmembrane LHCII antenna proteins between Photosystem II (PSII) and Photosystem I (PSI), which results from changes in their phosphorylation state. For the past two decades, two LHCII-kinase mutants, stt7-1 and stt7-9, have been instrumental in the study of STs in Chlamydomonas reinhardtii, the former being a null mutant for the kinase but quasi-sterile in crosses, while the latter, although fertile, has a leaky phenotype. Using long-read sequencing, this study further characterized the genetic lesions of the stt7 mutant strains through whole-genome reconstruction and de novo chromosome assembly. In addition, two new stt7 null mutants were generated, one derived by crosses from the original stt7-1 and one obtained by Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-associated protein 9 (Cas9) technology. This work provides a comprehensive genomic characterization of the original stt7-1 null mutant, revealing extensive chromosomal rearrangements and high levels of aneuploidy, associated with increased cell size and meiotic dysfunction. Reassessment of their physiology and genetic backgrounds highlights the need for caution in interpreting genetic information. We thus produced more reliable null mutants for the LHCII-kinase, amenable to genetic crosses for the study of STs in a variety of genetic backgrounds.

Chlamydomonas reinhardtii

Analysis of deep-resequencing data of 984 soybean accessions reveals structural variations underlying agronomic traits.

Genomic structural variants (SVs) are major sources of genetic variation and have profound impacts on phenotypic traits. However, their functional effects remain largely unexplored in soybean. Here, we resequence 940 soybean accessions. Together with 44 publicly available datasets, we identify 602,281 SVs. Using a graph-based genome, we detect&#xa0;an additional 58,760 presence/absence variations (PAVs) that broadly affect gene expression. Population genomic analyses reveal that SVs serve as a core driving force for soybean domestication and improvement. Integrating SVs with QTLs for oil and protein&#xa0;content, and performing GWAS on 27 traits, we identify key functional SVs. These include transposable element insertions altering seed coat color, multiple insertions within a cytochrome P450 gene modifying flower and hypocotyl color, and a GmMATE1 deletion enhancing seed size. Together, our study establishes a comprehensive SV map of soybean, offering a valuable resource for dissecting the genetic basis of complex traits to accelerate molecular breeding.

Glycine max

Beyond parental lines: multi-omics analyses reveal epigenetic and transcriptional mechanisms underlying heterosis in Oryza sativa &#xd7; Oryza rufipogon hybrids.

Heterosis, or hybrid vigor, refers to the superior phenotypes of a hybrid compared with their parents and is widely exploited in agriculture. Interspecific hybrids within the Oryza genus demonstrate significant potential for the systematic improvement of rice varieties. Nevertheless, the mechanistic basis underlying heterosis in interspecific Oryza hybrids remains poorly understood. Here, we systematically performed phenotypic characterization, whole-genome bisulfite sequencing, RNA sequencing, and small RNA profiling using Oryza sativa L. ssp. japonica cv. Nipponbare (NIP), Oryza rufipogon Griff. acc. CWR, and their resulting F1 hybrid (named as NC). NIP and CWR showed distinct phenotypic and molecular differences. The interspecific hybrid, NC, exhibited significant yield heterosis. In the hybrid, most epigenetic and transcriptional features displayed additive inheritance patterns relative to parental lines. Analysis revealed that domestication-selected genes maintained relatively low DNA methylation coupled with high expression levels in both hybrid and parental lines. Additionally, we identified that non-additive miRNAs were potentially involved in regulating fertility, cell growth, and cell division processes in the hybrid. A significant negative correlation was observed between DNA methylation level and gene expression. Functional enrichment analysis revealed that hybrid-MPV DEGs were significantly associated with flowering time regulation, carbohydrate metabolism, photosynthesis, protein phosphorylation, seed development, and defense responses. Through weighted gene co-expression network analysis, we identified 102 functional gene modules, six of which were significantly associated with yield-related heterosis. Collectively, our results provide a multi-omics framework for understanding interspecific hybridization between elite cultivars and wild rice relatives, highlighting CWR as an untapped genetic reservoir for rice improvement.

Oryza

Pinpointing genomic regions conferring herbicide tolerance in cassava via genome-wide association mapping.

Cassava (Manihot esculenta Crantz) is a tropical crop of major socioeconomic importance, whose productivity can be limited by sensitivity to herbicides used for weed management. This study aimed to perform a genome-wide association study (GWAS) in 194 cassava genotypes to identify genomic regions associated with tolerance to the herbicides mesotrione, S-metolachlor, and chloransulam-methyl. The evaluations performed at 3, 6, 9, 15, and 30 days after application (DAA) were used to characterize the temporal progression of phytotoxicity. Based on this analysis, the phenotype obtained at 9 days after application (PhytoX9DAA) was selected for genome-wide association analyses because it represented the period of greatest symptom expression and the highest discrimination among genotypes. GWAS analyses were performed using de-regressed BLUPs and the MLM, MLMM, and BLINK models, incorporating kinship (K) and population structure (Q) matrices. Significant markers were detected across multiple chromosomes, and the corresponding genomic windows contained candidate genes with functional annotations related to herbicide response. The predominant functional categories included membrane transport, channel activity, signal peptide processing, protein phosphorylation, cellular signaling, and metabolic regulation. Key candidate genes included Manes.02G151900 and Manes.02G152700 (chromosome 2), associated with transmembrane transport and signal peptide processing; Manes.09G060900 (chromosome 9), associated with protein kinase activity, ATP binding, and protein phosphorylation; and Manes.15G083800 and Manes.15G084000 (chromosome 15), associated with S-adenosylmethionine-dependent methyltransferase activity, membrane-related functions, and protein phosphorylation. These genes participate in biochemical pathways involved in cellular signaling, membrane transport, and metabolic regulation that may contribute to herbicide tolerance. Overall, the results demonstrate that herbicide tolerance in cassava is a quantitative and polygenic trait governed by numerous small-effect loci. The integration of cellular signaling, metabolic regulation, and membrane transport supports the physiological resilience of the species under chemical exposure, providing valuable insights for breeding strategies and marker-assisted selection.

Genome-Wide Association Study