Uneven crop stands arise from natural variations in emergence time, which are influenced by different irrigation measures applied post-sowing. In the pursuit of high-yielding maize populations, the emergence rate and uniformity of maize stands are critical factors. This study investigates the effects of different irrigation methods and drip irrigation at various days after sowing on the emergence uniformity and yield of summer maize. The experiment consisted of six treatments: drip irrigation on the 0th, 3rd, 6th, 9th, and 12th days after sowing (DAS0, DAS3, DAS6, DAS9, and DAS12), and sprinkling irrigation on the 0th day after sowing (SI0). Agronomic traits, ear characteristics, harvest yield, and indices of population uniformity were evaluated at critical growth stages. Results indicated that timely drip irrigation (DAS0-3) significantly increased the emergence rate and number of harvestable ears by 9.57% (8621.61 plants ha^-1) and 10.54% (8017.05 ears ha^-1) compared to the SI treatment. Treatment with DAS0-3 resulted in a significant increase of 13.50% in ear length and 24.85% in kernel weight per ear compared to the SI treatment. Maize populations subjected to delayed drip irrigation (DAS6-12) demonstrated a progressive decline in quality throughout the growth period. At the silk stage, the uniformity of plant height and ear height decreased by 47.19 and 44.85%, respectively, compared to the DAS0-3 treatment. Furthermore, at harvest, the uniformity of dry matter accumulation and leaf area index (LAI) was reduced by 28.24 and 41.83%, respectively, relative to the DAS0-3 treatment. Correlation analysis reveals that the uniformity of kernel weight per ear is most significantly associated with yield, as indicated by a correlation coefficient of 0.90^**. The yield in the DAS0-3 treatment was significantly higher than that in the SI treatment by 23.71%. The yields of the DAS6-12 treatments were notably lower than those of the DAS0-3 treatment, ranging from 13.18 to 23.97% lower, and were comparable to the yields observed in the SI treatment. The suboptimal implementation of drip irrigation technology has prevented it from realizing its potential for increasing crop yields. Each day’s delay in initiating drip irrigation after the third day post-sowing reduces yield by an average of 0.32 Mg ha^-1. Timely drip irrigation following maize seeding significantly enhances emergence rate and population uniformity, increases the number of harvestable ears and kernel weight per ear, ultimately leading to higher final yields. Drip irrigation for seedling emergence within three days after sowing can better bring out the yield-increasing potential of drip irrigation.

Prohexadione-calcium (Pro-Ca) has been shown to positively regulate crop tolerance to saline–alkali stress. However, the optimal concentration of Pro-Ca application and the mechanisms through which it enhances saline–alkali tolerance and yield in soybean remain unclear. This study aimed to determine the optimal concentration of exogenously applied Pro-Ca and reveal the mechanisms underlying Pro-Ca’s effect on remediation and yield response in soybean under saline–alkali stress. The results indicated that saline–alkali stress negatively impacted the morphological and physiological traits of soybean seedlings by triggering the production of reactive oxygen species (ROS), leading to oxidative damage of the grana lamellae due to excessive accumulation of Na⁺. An application of 100 mg L⁻¹ Pro-Ca was found to be optimal, promoting dry matter accumulation and normalized difference vegetation index (NDVI) by significantly reducing Na⁺ uptake under saline–alkali stress. Moreover, integrated physiological, ultrastructural, and transcriptomic analyses indicated that Pro-Ca significantly enhanced the ascorbate–glutathione (AsA–GSH) cycle by up-regulating the expression of related genes to enhance the activities of ascorbate peroxidase (APX), glutathione reductase (GR), dehydroascorbate reductase (DHAR), monodehydroascorbate reductase (MDHAR), and the AsA/dehydroascorbate (DHA) and GSH/oxidized glutathione (GSSG) ratios to quench ROS, thereby protecting both thylakoid and mitochondrial membranes from degradation. The differentially expressed genes (DEGs) encoding ascorbate and aldarate metabolism were significantly (P<0.05) enriched in the integral component of the membranes. Furthermore, Pro-Ca treatment up-regulated the expression of genes encoding photosystems under saline–alkali stress, thereby reducing the photoinhibition and stomatal limitation (L_s), mitigating damage to photosystems, and preventing yield reduction. In summary, foliar application of Pro-Ca could efficiently enhance soybean seedlings’ tolerance to saline–alkali stress by inhibiting Na⁺ influx, enhancing the AsA–GSH cycle, maintaining the biomembrane system, and improving photosynthetic efficiency.

Bud dormancy is a key adaptive strategy in perennial plants, enabling them to survive adverse environmental conditions. However, it poses challenges in crop cultivation, especially in fruit crops such as apple, in which synchronized bud break is crucial for consistent growth and yield. The synthetic cytokinin 6-benzylaminopurine (6-BA) promotes dormancy release; however, its molecular and metabolic mechanisms remain largely unclear. This study investigates dormancy release in nursery-grown Xianheng 01 apple rootstocks through integrated transcriptomic, metabolomic, and hormonal analyses. Dormant buds were treated with 6-BA, with morphological, biochemical, and molecular profiling performed over 30 d. 6-BA treatment increased plant height and leaf emergence by increasing the levels of cytokinins (DHZR, IPA) and decreasing the level of abscisic acid (ABA). Transcriptomics analysis identified 7,009 differentially expressed genes (DEGs) in response to 6-BA treatment. The cytokinin-responsive gene A-ARR8 exhibited a distinct expression pattern, being upregulated at 1, 3, and 6 d post-treatment but downregulated at 11 d. In contrast, ABA-related genes SnRK2a/b, PP2C, and ABF3, were consistently downregulated throughout the treatment period. Metabolomic analysis identified 2,053 metabolites, showing early-phase dominance of phenylpropanoids, and flavonoids, followed by a shift towards ABC transporter-mediated nutrient mobilization. Conjoint analysis highlighted the coordinated activation of secondary metabolite biosynthesis and cytokinin signaling. These results demonstrate that 6-BA induces dormancy release through cytokinin–ABA antagonism and phased metabolic reprogramming from stress defense to growth promotion. Our findings provide a comprehensive framework for optimizing dormancy management in apple cultivation and highlight 6-BA as an effective agrochemical for improving temperate fruit production.

The CONSTANS/CONSTANS-LIKE (CO/COL) gene family plays important roles in plants flowering and stress response. In this study, two variants of the MiCOL14B gene were identified from two different mango cultivars; they were designated as MiCOL14B-GQ and MiCOL14B-JH, which exhibited significant differences in sequence and B-box domain. Both genes were expressed in various tissues of mango, localized in the nucleus, and responsive to drought and salt stress. In transgenic Arabidopsis thaliana, MiCOL14B-GQ delayed flowering, while MiCOL14B-JH promoted flowering. This phenotypic divergence stemmed from their molecular regulatory specificity. Yeast one-hybrid (Y1H) and dual-luciferase reporter assays demonstrated that both variants directly bind to the promoters of florigen genes (MiFTs), with MiCOL14B-GQ repressing their transcription and MiCOL14B-JH enhancing it. Altered expression levels of MiFTs in the roots of transgenic mango further validated this mechanism. Moreover, both MiCOL14B-GQ and MiCOL14B-JH improved stress tolerance under drought and salt conditions in transgenic A. thaliana as well as in transgenic mango roots. These variants significantly increased stress tolerance by increasing proline (Pro) content and superoxide dismutase (SOD) activity, while reducing malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) accumulation. Yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays revealed that MiCOL14B-GQ and MiCOL14B-JH interact with several stress-related proteins. This study demonstrates for the first time the functional effects of sequence variation in the MiCOL14B gene on flowering and stress responses, providing valuable genetic resources for mango molecular breeding.

A novel variegated tea cultivar exhibiting a stable variegated phenotype was recently identified, demonstrating significantly elevated amino acid content concomitantly with reduced polyphenolic compound levels compared to conventional green-leaf varieties. Nevertheless, the underlying mechanism remains unclear. Here, variegated leaves and normal leaves of ‘Huangshanzhong’ tea plant were used to perform pigment content analysis and comparative transcriptome analysis. The chlorophyll content in variegated leaves significantly decreased compared to normal leaves, while the ratio of Chl a to Chl b was enhanced. Multiple genes (CsrpiA, CsGAPDH, CsPGAM, CsPK and CsOGDH) involved in sugar metabolism exhibited downregulated expression in variegated leaves. Key genes involved in the photosynthetic pathway were down-regulated in variegated leaves, including those encoding light-harvesting protein complex chlorophyll a/b binding proteins (CsLhca1, CsLhca4, CsLhcb1 and CsLhcb3) and photosystem II complex proteins (CspsbP and CspsbW). Meanwhile, genes involved in chlorophyll degradation metabolism (CsSGR and CsCLH1) were upregulated in variegated leaves. Compared to the wild type, transgenic plants overexpressing CsCLH1 and CsCLH2 exhibited no significant changes in chlorophyll content. Enzyme activity assays showed that CsCLH1 could degrade chlorophyll in vitro. Subcellular localization results revealed that CsCLH1 and CsCLH2 were localized in the cytoplasm and nucleus. These findings suggest that impaired photosynthetic system function, suppressed carbohydrate synthesis, and accelerated degradation of photosynthetic pigments collectively contribute to the variegated phenotype in tea leaves. This study advances our understanding of mechanisms underlying leaf variegation in plants.

The composition and function of root exudates in rhizosphere iron (Fe) mobilization are significantly influenced by environmental pH conditions. While the role of organic acids in Fe solubilization is well-recognized, the molecular mechanisms underlying this pH-dependent process remain poorly understood. Here, we demonstrate that under weakly acidic conditions, proton excretion alone is insufficient to solubilize sparingly soluble Fe. Instead, a pH-dependent ligand specificity emerges as a critical factor in Fe mobilization. Notably, within the pH range of 5.0–6.0, citric acid exuded by roots exhibits superior Fe solubilization efficacy compared to oxalic acid and malic acid. We identified SlFRDL1, a gene induced by Fe deficiency, as a key player in this process. SlFRDL1 encodes a plasma membrane-localized protein with citrate permeability, as confirmed by its functional expression in Xenopus oocytes. Knockout mutants of SlFRDL1 displayed exacerbated Fe deficiency symptoms, which were associated with a significant reduction in citrate secretion from roots. Furthermore, we discovered that SlSTOP1, a transcription factor, binds to the promoter region of SlFRDL1 and activates its expression. Slstop1 mutants exhibited leaf chlorosis symptoms similar to those observed in Slfrdl1 mutants, highlighting the functional interplay between these two genes. Interestingly, while Fe deficiency triggers the FER-mediated Fe uptake system under both acidic and alkaline conditions, the SlSTOP1–SlFRDL1 module is specifically activated only in acidic environments. This pH-specific regulation underscores the importance of the SlSTOP1–SlFRDL1 pathway in root-mediated Fe solubilization under acidic conditions.

Leaf curling is a key agronomic trait that promotes the formation of leafy heads in heading vegetable crops. However, the role of auxin in regulating leaf curling in Chinese cabbage remains largely unknown. In this study, we identified a Chinese cabbage mutant, lic86, which exhibited inward leaf curling and displayed significantly increased transverse curvature indices compared to the wild type. Additionally, among the measured hormones the concentration of indole-3-acetic acid (IAA) was significantly reduced in lic86. Exogenous application of IAA caused outward leaf curling, whereas applying the auxin transport inhibitor, TIBA, resulted in inward leaf curling in both wild type and lic86 plants. Transcriptomic analysis revealed that the differentially expressed genes between WT and lic86 were predominantly associated with hormone signal transduction pathways. Notably, the expression levels of two Brassica rapa asymmetric leaves1 (BrAS1) homologs were significantly elevated in lic86, while the expression of B. rapa LIKE-AUX1 (BrLAX1), the auxin influx carrier gene, was markedly downregulated compared to WT plants. Virus-induced gene silencing of BrLAX1 in WT plants resulted in leaf inward curvature, whereas silencing of BrAS1s in lic86 seedlings led to flattened leaf morphology. These findings offer insights into the molecular mechanism underlying leaf curling and leafy head development in Chinese cabbage.

Photosynthesis serves as the primary source of nutrients synthesized in higher plants, and improving photosynthetic efficiency can significantly increase crop yield and fruit quality. Leaf color mutants represent ideal materials for studying chloroplast development and photosynthesis mechanisms and have been widely characterized in field crops. However, relevant research on watermelon leaf color mutants remains scarce. In this study, we isolated a yellow-green phenotype mutant, PKH352, from an EMS-mutagenized watermelon mutant library. The chlorophyll content and maximal photochemical efficiency in PKH352 were significantly decreased. Genetic analysis showed that the mutated trait was controlled by a single nuclear gene, which was named Clygp (Citrullus lanatus yellow-green plant). Through MutMap and linkage analysis in an F₂ population of 440 plants, we identified a single nucleotide polymorphism (SNP) mutation within ClG42_04g0106300, which encoded a signal recognition particle 54 kDa protein, as the causal variant for the yellow-green phenotype. Further validation using a CRISPR/Cas9-mediated system confirmed that knockout of ClG42_04g0106300 results in the yellow-green phenotype in watermelon. In addition, comparative transcriptomic analysis revealed that mutations in ClG42_04g0106300 greatly affected the expression of key genes associated with chloroplast development and photosynthesis, providing strong evidence that this gene plays a critical role in these biological pathways. Taken together, these findings provide insights into the molecular mechanisms underlying chloroplast development and photosynthetic efficiency, offering a theoretical basis for breeding watermelon varieties with high photosynthetic efficiency.

Plant pathogenic fungi release cell wall-degrading enzymes (CWDEs), which are significant weapons for breaking down plant cell walls, although only a few reports focus on their pathogenesis. The current study demonstrates that MoFco1, a conserved α-L-fucosidase in several pathogenic fungi, degrades the hemicellulose component XXFG and contributes to the pathogenicity of Magnaporthe oryzae. In addition, MoFco1 enzyme activity is essential for its pathogenic function, as the enzyme activity mutation induced pathogenesis defects identical to the ΔMofco1 mutant. We further performed a structure-based virtual screening targeting MoFco1 and discovered 0989, which binds to MoFco1 and effectively inhibits M. oryzae pathogenesis. In brief, our study reveals the pathogenic mechanism of MoFco1 and explored the application of structure-based virtual screening in plant protection.

The explosive increase in the use of unmanned aerial vehicle (UAV) sprayers has put forward new requirements for pesticide formulations, and there is an imperative necessity to develop targeted, precise, and efficient pesticide formulations based on the surface characteristics of targets to meet the demand for low-volume spraying by UAVs. Herein, a performance-matched oxaziclomefone nanosuspension (NS) was constructed based on the hydrophobic surface characteristics of barnyardgrass for UAV sprayers. The results showed that the solid surface free energy of the adaxial and abaxial surfaces of barnyardgrass at different growth stages ranged from 23.73 to 28.00 mJ m^–2 and was dominated by dispersive components. The average sizes of micro-nanostructures on the barnyardgrass surfaces ranged from 251.7 to 266.8 nm, and the oxaziclomefone nanoparticles in the NS could be suitably embedded into the micro-nanostructures of the barnyardgrass surface. The atomization test showed that the NS could significantly decrease the percentage of spray droplets with sizes for droplet drift. Due to the precise regulation of the formulation components, the NS exhibited superior wetting, spreading, and adhesion performance on the barnyardgrass surface. Moreover, the NS remarkably enhanced the uptake and translocation of oxaziclomefone in barnyardgrass. Field trials showed that, compared to the commercial formulation, the NS could significantly improve the control efficacy against barnyardgrass in direct-seeded rice fields while demonstrating acceptable safety for rice. Our research provides a novel, promising, and feasible strategy for the development of pesticide formulations based on target surface characteristics and for improving the physicochemical properties of dilutions, which is valuable for enhancing dosage delivery efficiency and improving control efficiency against pests for UAV sprayers.