Search Results (579)

The normal metabolism of transient starch in leaves plays a vital role in determining photosynthesis and final crop yield. However, the molecular mechanisms linking abnormal transient starch metabolism to premature leaf senescence remain unclear. Here, we isolate a rice mutant, lses1, with leaf yellowing and premature senescence, as well as excessive accumulation of starch granules in chloroplasts. Genetic analysis revealed that this trait is controlled by a single recessive nuclear gene. Through BSA-seq preliminary gene mapping, map-based cloning, and sequencing alignment, the candidate gene was pinpointed to LOC_Os02g40860 on chromosome 2, which encodes OsCKI1, a casein kinase I family member. The identity of LSES1 was confirmed functionally: genetic complementation with the native genomic sequence rescued the wild-type phenotype, while CRISPR/Cas9 knockout of the gene in wild-type plants recapitulated the premature senescence. This confirmed that LSES1/OsCKI1 is involved in the regulation of leaf senescence. Notably, one improved knockout line, KO-2, displayed significant agronomic improvements in grain length, grain width, number of productive ears, and number of filled grains per panicle, along with a significant increase in grain yield per plant, highlighting its potential breeding value. Subcellular localization and tissue-specific expression analysis showed that LSES1 is primarily nuclear-localized and constitutively expressed. Full article

A two-year field study was performed to evaluate the cadmium (Cd) phytoremediation potential of two hyperaccumulators, Sedum alfredii (S.A.) and Sedum plumbizincicola (S.P.), in contaminated farmland. Biomass and Cd uptake in both species followed logistic growth models. S.A. reached maturity about 20 days earlier than S.P., with optimal harvest timing at the early late-flowering stage (early–mid May), compared to the full late-flowering stage (early June) for S.P. The primary Cd-accumulating organs were stems and flowers in S.A. and leaves and stems in S.P. Under identical conditions, S.P. exhibited higher theoretical biomass, Cd content, bioconcentration factor (BCF), and Cd uptake, supported by transcriptomic data showing upregulation of metal transporter and stress-related genes under Cd exposure. However, S.P. demonstrated greater environmental sensitivity and lower stress resistance, resulting in more variable real-world remediation efficiency than S.A. It is recommended to harvest at flowering stages, enhance biomass in key Cd-accumulating tissues, and select species based on local conditions. Future work should aim to breed Sedum varieties with greater biomass, Cd accumulation capacity, and stress tolerance. This study provides actionable insights for optimizing the timing and species selection in Cd phytoremediation. Full article

Melatonin and hydrogen sulfide (H₂S) have both been demonstrated to enhance plant drought tolerance. However, the relationship between melatonin and H₂S during the drought resistance response remains unclear. In this study, under drought stress, the synthesis pathways for both melatonin and H₂S in maize seedlings were activated. The application of exogenous melatonin enhanced the expression of key genes, namely LCD and DCD, which are involved in H₂S synthesis, thereby promoting the accumulation of H₂S. Conversely, the application of NaHS did not significantly influence the expression of genes related to melatonin synthesis or the levels of endogenous melatonin. Melatonin enhanced drought tolerance in maize through the H₂S signaling pathway, as evidenced by a 124.1% increase in the photosynthetic rate and improved activity of antioxidant enzymes. Specifically, there were increases of 66.5%, 75.6%, and 51.0% in the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), respectively. Furthermore, there was an elevation in the levels of osmotic regulatory substances and non-enzymatic antioxidants. The application of the H₂S scavenger (HT) significantly inhibited the drought tolerance effects mediated by melatonin, whereas the melatonin synthesis inhibitor (p-CPA) did not exert a significant impact on the drought resistance induced by H₂S. Overall, our findings suggest that H₂S plays a role in the melatonin-mediated enhancement of drought tolerance in maize, primarily through coordinated modulation of osmotic balance and antioxidant defense systems. Full article

The accumulation of photoassimilates in the sinks during the grain filling stage is affected by the conditions of the various source organs. This study was conducted to investigate changes in various source and sink organs when the flag leaves and spikes were shaded from heading to harvest in wheat. Shading the flag leaves increased chlorophyll content and chlorophyll fluorescence in the uppermost leaves by 34.9% and 0.3% in 2022 and 75.3% and 3.3% in 2023, respectively, maintaining a relatively high photosynthetic rate from heading to the mid-grain filling stage. However, shading the spikes had a more substantial negative impact on spike growth than the flag leaf shading. On the other hand, the uppermost leaves continued to serve as a source more actively even when the flag leaves were shaded, implying a compensating effect. At 35 days after treatment (DAT), the relative water content (RWC) of the spike in the spike shading (SS) treatment was 19.4% and 49.7% higher than that of the control in 2022 and 2023, respectively. However, grain weight in the SS treatment decreased by 39.7% in 2022 and 5.3% in 2023 compared with the control. In the flag leaf shading (FS) treatment, grain weight declined by 3.5% and 6.2% in 2022 and 2023, respectively. These results indicate that the reduction in grain weight due to shading was less pronounced in the SS treatment than in the FS and combined flag leaf and spike shading (FSS) treatments. The results suggest that spikes play a buffering role when assimilate-transport functions decline in the source organs. Our results provide a better understanding of the architectural properties, including flag leaf, spike, and the uppermost leaf, for photosynthetic contribution to grain filling in wheat. Also, identifying target characteristics for improving photosynthetic source organs will be valuable for developing wheat varieties with high yield stability. Full article

Experimental studies published to date on the effects of silver nanoparticles (AgNPs) on plants have yielded highly contradictory results: reported outcomes range from growth inhibition to stimulation. The objective of this research was to test the hypothesis that the ontogenetic stage at the time of exposure to AgNPs is a key determinant of both the qualitative profile and quantitative magnitude of plant responses. For this purpose, laboratory seed priming and small-plot field experiments with wheat plants (Triticum aestivum L.) treated with stabilized dispersions of AgNPs at 1–100 mg∙L⁻¹ were conducted. It was shown that seed priming with low concentrations of AgNPs (1–5 mg∙L⁻¹) did not affect wheat seedling growth, whereas dispersions at ≥25 mg∙L⁻¹ suppressed development. In agreement, antioxidant enzyme activities (POD, CAT, PPO) increased at 1–5 mg·L⁻¹ and decreased at 100 mg·L⁻¹. By contrast, foliar treatments of field-grown wheat increased plant population density, plant height, spike structure metrics, and grain yield. The optimal regimen—three foliar applications at 5 mg·L⁻¹—increased grain yield by 12.1% from 5.89 t·ha⁻¹ to 6.60 t·ha⁻¹. At low doses of AgNPs, activities of peroxidase, catalase, and polyphenol oxidase in seedlings tissues increased, indicating activation of nonspecific defense mechanisms; at higher concentrations, activities of these enzymes decreased, indicating antioxidant system exhaustion and dysfunction. The findings demonstrate dose- and stage-dependent effects and corroborate the central role of the developmental stage of wheat in determining responses to AgNPs, indicating opportunities to optimize stage-aware, low-dose application regimes to enhance productivity while minimizing phytotoxic risk. Full article

Drought stress severely constrains yield and quality stability in longan (Dimocarpus longan Lour.), an important medicine and food homology fruit in China. Melatonin (MT) shows potential for alleviating abiotic stress, but its mechanisms in drought-stressed longan remain unclear. Here, we investigated two cultivars (Shixia and Chuliang) under drought and exogenous MT treatments (CW, well-watered control; CM, exogenous MT application under well-watered control; DW, drought stress; DM, exogenous MT application under drought stress), revealing the following findings: (i) Drought treatment significantly reduced endogenous MT levels in both studied cultivars, and the reduction was reversed by exogenous foliar MT application. Specifically, under drought conditions, exogenous MT treatment increased endogenous MT content by 272.7% in Shixia and 53.6% in Chuliang, respectively. (ii) Drought and exogenous MT treatments modulated the activities of plant defense enzymes (superoxide dismutase, SOD; peroxidase, POD; phenylalanine ammonia lyase, PAL; and catalase, CAT) and the levels of related metabolites (malondialdehyde, MDA; proline, Pro). Across both cultivars, drought stress increased the activities of SOD, POD, and PAL, as well as the Pro content. Exogenous MT treatment, however, reduced the activities of SOD, POD, and PAL while increasing CAT activity and MDA content to some extent in both cultivars. Notably, the Pro content was significantly reduced in Shixia but significantly increased in Chuliang following exogenous MT application under drought stress. (iii) Drought and exogenous MT treatments regulated gene expression in longan cultivars. Relative to CW, 848, 3356, and 2447 differentially expressed genes (DEGs) were detected in CM, DW, and DM in Shixia, respectively. Relative to CW, 1349, 5260, and 5116 DEGs were identified in CM, DW, and DM in Chuliang. A gene ontology analysis indicated significant enrichment for abiotic stress defense and hormone-responsive processes. The KEGG pathway analysis showed significant enrichment in protein processing in the endoplasmic reticulum (ko04141), amino sugar and nucleotide sugar metabolism (ko00520), ascorbate and aldarate metabolism (ko00053), plant–pathogen interaction (ko04626), and starch and sucrose metabolism (ko00500). These findings provide physiological and transcriptomic insights into MT-regulated drought responses in longan, highlighting its potential for improving productivity in drought-prone regions. Full article

While the molecular mechanisms of cadmium (Cd) uptake are well-studied in rice and tobacco, hexaploid wheat remains less explored. Elucidating the roles of transporter genes in Cd uptake and translocation in wheat is critical for minimizing Cd accumulation in grains. This study compared the differences in the expression levels of Cd transporter families (including the natural resistance-associated macrophage protein (NRAMP), heavy metal ATPase (HMA), zinc-regulated transporter/iron-regulated transporter (ZIP), and yellow stripe-like (YSL) families) between two high Cd-accumulating wheat varieties and two low Cd-accumulating wheat varieties using qPCR. We found that low Cd-accumulating wheat varieties had higher expression levels of TaNRAMP5 and TaHMA2 in roots and TaHMA3 in aboveground tissues, and lower expression levels of TaNRAMP6, TaZIP5, and TaYSL6 in both roots and aboveground tissues compared to the high Cd-accumulating wheat varieties. Mantel test analysis revealed that the root expression levels of TaNRAMP5 and TaNRAMP6 and aboveground expression levels of TaZIP6 and TaHMA2 were significantly correlated with the Cd content of wheat tissues. Furthermore, the expression levels of TaZIP5 in roots and TaZIP5 and TaHMA3 in aboveground tissues were significantly correlated with the Cd translocation factor from roots to aboveground tissues, suggesting that TaNRAMP5, TaNRAMP6, TaZIP6, and TaHMA2 played key roles in Cd uptake and accumulation in wheat, and TaZIP5 and TaHMA3 were closely associated with Cd translocation from roots to aboveground tissues. Compared to low Cd-accumulating varieties, high Cd-accumulating wheat varieties exhibit significantly elevated levels of thiol-containing compounds for Cd chelation, including glutathione (7.65%~75.5% higher), phytochelatins (2.35%~47.2% higher), and non-protein thiols (13.2%~37.1% higher). These findings deepen insights into wheat Cd absorption processes. The identified transporter genes could serve as foundational resources for future breeding strategies aimed at reducing Cd accumulation in wheat, pending further functional validation. Full article

To investigate the photosynthetic characteristics and leaf anatomical structures of seedlings from the endangered plants Ormosia olivacea, Ormosia pachycarpa, and Ormosia sericeolucida, this study aimed to elucidate the influence of leaf structure on photosynthetic traits and light requirements among these three Ormosia species, thereby providing reference for their introduction and cultivation. This study measured the light response curves, CO₂ response curves, leaf epidermal and anatomical characteristics, and photosynthetic pigment content of the three Ormosia species. Results indicate: 1. All three species exhibit photophilic tendencies, with Ormosia olivacea demonstrating the highest photosynthetic capacity, achieving a maximum net photosynthetic rate (Pmax) of 1.9062 mol m⁻² s⁻¹. Ormosia pachycarpa exhibited the highest potential maximum net photosynthetic rate (Amax), demonstrating superior CO₂ utilisation capacity. The Amax values for all three species were significantly higher than their Pmax values. 2. Among the three Ormosia species, Ormosia sericeolucida exhibited the thickest leaf structure, with palisade tissue thickness ordered as follows: Ormosia sericeolucida > Ormosia pachycarpa > Ormosia olivacea. 3. Stomata were present on the lower epidermis of all three species. Ormosia sericeolucida possessed the largest individual stomatal area, while Ormosia olivacea exhibited the highest stomatal density. 4. The chlorophyll a content (Chl a) of all three Ormosia species exceeded their chlorophyll b content (Chl b), indicating they are photophilic plants. Ormosia sericeolucida exhibited higher chlorophyll a (Chl a), chlorophyll b (Chl b), and total chlorophyll (Chl) contents than both Ormosia olivacea and Ormosia pachycarpa. Ormosia olivacea possessed the highest carotenoid content (Car). In summary, Ormosia pachycarpa exhibited the highest potential maximum net photosynthetic rate (Amax), demonstrating the strongest CO₂ utilisation capacity, followed by Ormosia olivacea, with Ormosia sericeolucida showing the lowest. Appropriately increasing CO₂ levels in cultivation sites would benefit photosynthesis and material accumulation in all three Ormosia species, promoting robust growth. Full article

To address the limitations of traditional wheat quality breeding, this study developed a Wheat Quality Molecular Marker Selection System (QMMS) by integrating key genetic loci controlling core quality traits: grain protein content (GPC), grain hardness (GH), and high-molecular-weight glutenin subunits (HMW-GS). The QMMS comprises three KASP markers (Kgpc-2B, Kgpc-2D, Kgpc-4A) and two duplex KASP (dKASP) markers (Pin-ab, Glu-AD), enabling cost-effective (≈5 CNY per sample) and high-throughput genotyping. Systematic validation was conducted using four panels of materials: representative varieties, breeding nursery materials, regional trial materials from the Middle and Lower Reaches of the Yangtze River, and advanced lines from four cooperative institutions. Results showed that (1) the QMMS accurately distinguished quality types of representative varieties: strong-gluten varieties carried five or more strong-gluten–favorable alleles, while weak-gluten varieties harbored five or more weak-gluten favorable alleles; (2) in breeding nursery materials, quality traits increased significantly with the number of aggregated strong-gluten favorable alleles, and 48.15% of strong-gluten candidates met strong- and medium-strong-gluten standards; (3) in regional trial materials, 15.25% (36/236) and 1.69% (4/236) of lines carried ≥5 strong-gluten and weak-gluten favorable alleles, with low utilization of Kgpc-2D and Pina/Pinb favorable alleles (<30%); and (4) the QMMS screened 273 strong-gluten and 27 weak-gluten candidates for cooperative institutions, matching their breeding focuses. In conclusion, the QMMS provides reliable technical support for precise and efficient wheat quality breeding. Full article

The Pheophorbide a oxygenase (PaO) is a key enzyme in chlorophyll degradation and plays an important role in plant senescence. However, the PaO gene’s function in sorghum remains underexplored. In this study, we identified five SbPaO gene family members in the sorghum genome through bioinformatics analysis. Analyses of gene structure, phylogeny, and collinearity revealed high conservation of this gene family among grass crops, suggesting similar functions. Subcellular localization and protein network predictions indicated that SbPaOs may participate in chlorophyll catabolism and regulate leaf senescence. Expression pattern analysis showed that SbPaO1, SbPaO3, SbPaO4, and SbPaO5 were highly expressed in leaves and significantly upregulated during senescence. Haplotype analysis found three SbPaO genes significantly linked to thousand-grain weight (TGW); superior haplotypes SbPaO1-hap4, SbPaO3-hap5, and SbPaO4-hap4 notably increased this trait. Single-gene improvements increased TGW by 10.57–17.20%, dual-gene aggregation by 18.78–24.75%, and three-gene aggregation by 29.09%. The study also developed Kompetitive Allele-Specific PCR (KASP) markers that identify superior haplotypes with 100% accuracy. In summary, this study’s results provide a theoretical basis and genetic resources for further exploration of haplotype pyramiding strategies to breed new high-yielding sorghum varieties and delineate a clear research direction for subsequent functional validation and breeding practices. Full article

Starch granule size distribution plays a vital role in determining the physicochemical properties and processing quality of soft wheat. This study analyzed fourteen soft wheat varieties cultivated in the Huaihe River Basin, an agriculturally important but underrepresented region, to evaluate starch granule size distribution, pasting properties, and their interrelationship. The starch granules were categorized into four size classes, with the volume dominated by A-type granules (>10 μm), while numerically, the majority were <2.8 μm. Pasting characteristics measured by the Rapid Visco Analyzer revealed substantial variation among genotypes. Varieties with a higher proportion of A-type granules exhibited stronger pasting profiles, including higher peak and final viscosities, whereas those with more B-type granules showed lower values. These observations indicate a clear relationship between granule morphology and starch functionality. In the present study, there was a significant positive correlation between peak viscosity, final viscosity, and set-back viscosity. The volume % of granules > 10 μm showed a positive correlation with peak viscosity (r = 0.53 *), final viscosity (r = 0.57 *), and set-back (r = 0.53 *), while the volume percentage of granules < 10 μm was significantly negatively correlated with peak viscosity (r = −0.53 *), final viscosity (r = −0.57 *), and set-back (r = −0.53 *) value. It indicated that the higher the percentage of granules > 10 μm, the higher the peak viscosity, final viscosity, and set-back value in soft wheat grain. Full article

In Xinjiang, soybean yield potential is constrained by varietal limitations and abiotic stresses. Although plant growth regulators (PGRs) can enhance crop yield, their specific impacts on soybean production, endogenous hormone regulation, and nutrient dynamics in this region have not been well characterized. This study evaluated the effects of different PGR treatments on yield formation, hormone levels, and nutrient contents through a field experiment conducted in Ili, Xinjiang, from 2023 to 2025. Foliar applications of naphthaleneacetic acid (NAA, 300 g ha⁻¹), prohexadione-calcium (Pro-Ca, 450 g ha⁻¹), and iron chlorine e6 (ICE6, 45 g ha⁻¹) were applied twice—at the fourth trifoliolate and full-pod stages—with an untreated control (CK) for comparison. Compared with CK, PGR treatments increased biomass allocation to reproductive organs by 6.2%, nutrient accumulation of N, P, and K by 12.3%, 25.5%, and 6.5%, respectively, pod number by 6.92 pods per plant, seed number by 4.86 seeds per plant, and 100-seed weight by 0.47 g, resulting in 6.6–12.0% higher grain yield. Seed PGR residues were 0.009 mg kg⁻¹. PGR application enhanced reproductive organ conversion capacity, nutrient uptake efficiency, and regulated endogenous hormone levels, clarifying internal yield-formation mechanisms and offering valuable reference for soybean research, particularly in similar latitudes. Full article

Despite the extensive cultivation of Moringa trees in tropical regions, understanding of accession-specific performance across diverse agroecological zones remains inadequate. Thus, this study evaluated the growth, adaptability, and leaf yield performance of 12 Moringa accessions (11 M. oleifera and 1 M. stenopetala) over three years in a subtropical climate (Pretoria, South Africa). Seeds were planted in seedling trays in the glasshouse at the University of Pretoria’s experimental farm. Vigorous seedlings were transplanted to the field at the Roodeplaat experimental site of the Agricultural Research Council two months after establishment, following a randomized complete block design (RCBD). Data were measured on establishment (emergence, survival), growth and yield parameters, and monitored plant health via leaf greenness, vigour, chlorosis, and pest and disease incidence. Accessions exhibited substantial variation for most traits, except for stem diameter. Moringa stenopetala showed the highest initial emergence rate but later displayed lower survival rates than most M. oleifera accessions. Survival rates, morphological features (plant height, canopy diameter, and branching), visual scores for leaf greenness and plant vigour, and leaf yield (fresh and dry) varied considerably among the accessions. Moringa oleifera A2 consistently performed well, exhibiting vigorous growth, the maximum survival rate (78%), and fresh leaf production (6206 kg ha⁻¹). Accessions A3 and A8 showed intermediate yield and longevity, indicating potential for cultivation or breeding. Conversely, M. oleifera A10 and M. stenopetala markedly underperformed in most traits, limiting their cultivation potential. Based on multi-year performance, A2 is suggested for large-scale cultivation due to its vigour, yield, and stress tolerance, while A3 and A8 hold breeding potential. The study emphasizes the critical role of genetic variation and selection in enhancing Moringa productivity under subtropical environments. Future work should focus on genetic characterization and agronomic practices optimization of superior accessions. Full article

Banana is a globally important food crop. As a large herbaceous plant with a shallow root system, its yield is highly susceptible to drought stress. ANP family genes play crucial roles in plant drought resistance. However, the ANP gene family has not been systematically studied in bananas, and how Piriformospora indica (P. indica) induces its expression remains unclear. A comprehensive identification of the ANP family is thus a necessary foundation for functional studies. In this study, we systematically identified 13 ANP family members in banana for the first time through genome-wide analysis. Using bioinformatics, RT-qPCR and subcellular localization techniques, we characterized their structural features, phylogenetic relationships, and the expression patterns of MaNPK1 under drought stress and P. indica colonization. The results revealed that banana ANP family members are highly evolutionarily conserved. MaNPK1-1 was specifically induced and upregulated by P. indica under drought conditions and subcellular localization showed that it played a role in the nucleus. This research provides theoretical insights into the function of the banana ANP family and its regulatory role in the P. indica mediated drought stress response, offering potential applications for breeding stress resistant banana varieties. Full article

Nuts, including tree nuts such as almonds, walnuts, cashews, and macadamias, as well as peanuts, are widely consumed for their health benefits owing to their high-quality protein content. Globally, the nut industry represents a multi-billion-dollar sector, with increasing demand driven by consumer interest in nutrition, functional foods, and plant-based diets. Recent advances in proteomic technologies have enabled comprehensive analyses of nut seed proteins, shedding light on their roles in nutrition, allergenicity, stress responses, and food functionality. Seed storage proteins such as 2S albumins, 7S vicilins, and 11S legumins, are central to nutrition and allergenicity. Their behavior during processing has important implications for food safety. Proteomic studies have also identified proteins involved in lipid and carbohydrate metabolism, stress tolerance, and defense against pathogens. Despite technical challenges such as high lipid content and limited genomic resources for many nut species, progress in both extraction methods and mass spectrometry has expanded the scope of nut proteomics. This review underscores the central role of proteomics in improving nut quality, enhancing food safety, guiding allergen risk management, and supporting breeding strategies for sustainable crop improvement. Full article