Citrus production in western Hubei, a subtropical region of central China, is constrained by seasonal water scarcity and excessive nitrogen application, creating a major challenge in reducing water and nitrogen inputs while maintaining yield stability and improving resource-use efficiency. Moreover, how different mulching materials modulate citrus responses under deficit irrigation and reduced nitrogen application remains unclear. Therefore, a multifactor field experiment integrating mulching type, irrigation, and nitrogen application was conducted to evaluate their combined effects on citrus photosynthetic traits, yield formation, water-use efficiency (WUE), and nitrogen partial factor productivity (NPFP). The field experiment was conducted in Zhijiang, Hubei Province, China, in 2023 and 2024 using an L9(3 4 ) orthogonal design, incorporating three irrigation levels (W1: 80% θf - 90% θf ; W2: 70% θf - 80% θf ; W3: 60% θf - 70% θf , where θf denotes field capacity, defined as the soil water content retained after gravitational water has drained from fully wetted soil), three nitrogen rates (N1: 80% N0; N2: 70% N0; N3: 60% N0, where N0 = 300 kg·ha -1 ), and three mulching materials (M1: white transparent film; M2: black opaque film; M3: silver-black double-color reflective film). (1) Irrigation amount (W) and nitrogen rate (N) were the primary factors influencing the measured variables, whereas mulching material (M) had a comparatively smaller effect. The main effects of all three factors were significant for most variables ( P < 0.05). Interaction analyses indicated significant W × M and N × M effects on most variables, whereas W × N effects were comparatively limited. (2) As water and nitrogen supply decreased, Pn, Tr, Gs, and CE declined concurrently. Compared with T1 (W1N1M1), Pn decreased by 1.02%–24.36% under the other treatments. Ci declined in parallel with Pn under W1 and W2 but increased under W3. Fruit number and single-fruit weight responded differently to irrigation, nitrogen application, and mulching, The two variables reached their highest values under T1 and T5, respectively, and were significantly higher than their corresponding values under all W3 treatments ( P < 0.05). (3) Using the criterion that yield, WUE, and NPFP each reached at least 90% of its respective maximum, the model-estimated suitable water and nitrogen ranges within the experimental domain were M1 (W = 687–800 mm, N = 180–208 kg·ha -1 ), M2 (W = 706–740 mm, N = 219–237 kg·ha -1 ), and M3 (W = 776–800 mm, N = 205–226 kg·ha -1 ). (4) Path analysis and PLS-PM yielded positive path coefficients from irrigation, nitrogen application, and mulching material to photosynthetic traits ( β = 0.87, 0.33, and 0.05, respectively), from photosynthetic traits to growth indicators ( β = 0.93), and from growth indicators to yield ( β = 0.78). Fruit number had a greater path coefficient for yield than single-fruit weight. These findings provide a theoretical basis and quantitative practical references for the selection of mulching materials and precise water-nitrogen management in citrus under deficit irrigation and reduced nitrogen fertilization in Western Hubei.
Wheat powdery mildew poses a serious threat to global wheat production, and its accurate identification is key to smart agriculture. This study combines chlorophyll fluorescence imaging with deep learning algorithms to investigate the temporal dynamics of key fluorescence parameters (such as maximum photochemical efficiency, QYmax) during the progression of powderymildew. A QYmax-based chlorophyll fluorescence image dataset for wheat powdery mildew was constructed. Building on this, the LCRNet model was proposed, which effectively processes fluorescence image data through a collaborative mechanism integrating the Large Selective Adaptive Fusion (LSAF) and Coordinated Attention (CA) modules. On an independent test set, the model achieved an accuracy of 94% and an F1 score of 94.1%, outperforming comparison models. This study proposes a method for classifying the severity of powdery mildew in wheat that reduces the computational cost of fluorescence data processing, providing important methodological support and technical insights for advancing the intelligent, precise, and green transformation of crop disease prevention and control systems.
Rong He, Wenfei Xian, Yan Xu, Dehua Ji, Chaotian Xie, Wenlei Wang
The transition from conchocelis to conchosporangial branches is not only a key stage in the life cycle of Pyropia/Porphyra but also directly affects the yield and quality of economically important species such as Pyropia haitanensis . However, the molecular mechanisms underlying the maturation of P. haitanensis filaments remain poorly understood. Hydrogen peroxide (H 2 O 2 ), as an important signaling molecule, plays a significant role in algae development. This study demonstrated that treatment with the H 2 O 2 scavenger DMTU (500 μmol/L) significantly reduced H 2 O 2 and O 2 - levels within the algae, affecting the activity of antioxidant enzymes and the content of antioxidant substances. This disrupted the ROS balance, inhibited key pathways such as photosynthesis and nitrogen metabolism, and triggered dysregulation in downstream metabolite synthesis. Consequently, the levels of most amino acids and their derivatives, nucleotides, and lipids were decreased. This diverted energy and resources from the “maturation program” towards a “stress-response program,” thereby delaying conchocelis maturation. Notably, this inhibitory effect was reversible following DMTU removal. When unfavorable conditions necessitate delayed maturation induction, intervention with DMTU could be applied to effectively reduce the risk of conchospore “abortion”. In summary, H 2 O 2 is a critical signaling molecule regulating the maturation of P. haitanensis conchocelis. This study provides a theoretical basis for elucidating the molecular regulatory network governing conchocelis maturation in Pyropia/Porphyra and achieving precise regulation of synchronized maturation.
Jiyoung Park, Kihwan Kim, Junseop Shin, Deokmoon Lee, Hyunsung Lee, Hyun Jo, Jong Tae Song, Won-Chan Kim, Jeong-Dong Lee
Soybean seed oil quality is governed by the relative proportions of five major fatty acids. Most genetic studies of soybean fatty acid mutants have evaluated allelic effects primarily on fatty acid composition, rather than quantifying their corresponding contents. Because fatty acid composition is expressed as relative percentage of total fatty acids, an increase in the proportion of one fatty acid is necessarily accompanied by a relative decrease in others, making it difficult to distinguish compositional shifts from changes in the actual amount accumulated per unit seed mass. In this study, we characterized PE1604, an EMS-induced mutant derived from the Korean soybean cultivar Pungsannamul and evaluated fatty acid phenotypes using both composition and contents. Sequence analysis identified a C to T transition in KASII - A (Glyma.17G047000) that resulted in an L263F amino acid substitution at a leucine residue conserved among KASII-A homologs from 11 species of the family Fabaceae. AlphaFold2 models superposed on the Escherichia coli ( E . coli ) FabF complex with crypto - 1b-AcpP (C16-AcpP) placed Leu263 within the buried hydrophobic core of KASII-A, distant from the catalytic residues Cys240, H380, and H416 in the active site. FoldX predicted a destabilizing effect of 6.83 kcal/mol for L263F, attributed to van der Waals clashes. Rosetta analysis also indicated a destabilizing energetic change of 11.57 REU. In F 2 populations derived from Pungsannamul × PE1604 and Seonpung × PE1604, palmitic acid composition increased from 12.1% in KASII - A homozygotes to 18.1% in kasII - a homozygotes and 11.7% in KASII - A homozygotes to 17.4% in kasII - a homozygotes, respectively. In addition, analysis of fatty acid content showed that palmitic acid content in kasII - a homozygotes progeny paralleled the difference in palmitic acid content between the parental lines. Seonpung contained approximately 33.5 mg/g seed weight palmitic acid content, and kasII - a homozygotes progeny from the Seonpung × PE1604 cross accumulated 51.9 mg/g seed weight, wherease Pungsannamul conta0ined approximately 23.1 mg/g seed weight and the corresponding progeny from the Pungsannamul × PE1604 cross accumulated 38.2 mg/g seed weight. These results suggest that the L263F amino acid substitution may affect KASII-A through altered local packing and protein stability rather than direct perturbation of the catalytic site.
Wheat lodging remains a major constraint to sustainable wheat production because it reduces grain yield and quality, increases harvesting losses and lowers production efficiency. The widespread cultivation of high-yielding cultivars, intensive nitrogen fertilization, higher planting densities, expansion of irrigated agriculture, and increasingly frequent extreme weather events have collectively increased lodging susceptibility, making effective management an important priority. Lodging is a complex phenomenon governed by interactions among plant architecture, stem mechanical properties, root anchorage, crop management practices and environmental conditions. Consequently, improving lodging resistance requires an integrated approach that combines physiological understanding with practical agronomic interventions. This review synthesizes recent advances in the structural, physiological, biochemical and agronomic mechanisms underlying lodging resistance in wheat. Particular emphasis is placed on stem biomechanics, basal internode characteristics, cell wall composition, lignin and cellulose deposition, root system architecture, and genetic factors that collectively determine plant stability. The review further examines the influence of major agronomic practices, including nitrogen management, plant population, sowing time, irrigation scheduling and cultivar selection, on lodging risk under diverse production environments. In addition, the physiological responses, field performance, practical applications and limitations of commonly used plant growth regulators, including chlormequat chloride, trinexapac-ethyl, paclobutrazol, uniconazole and ethephon, are critically evaluated in relation to their roles in improving stem strength and reducing lodging. The available evidence indicates that no single strategy provides consistent lodging control across all production systems. Instead, durable improvement in lodging resistance depends on integrating genetic improvement, balanced crop nutrition, optimized agronomic management, and judicious use of plant growth regulators according to local environmental conditions. The review also highlights emerging opportunities offered by precision agriculture, high-throughput phenotyping, advanced spray technologies, and improved understanding of stem biomechanics and root anchorage. Together, these advances provide a framework for developing sustainable, climate-resilient lodging management strategies that enhance wheat productivity, crop stability and resource-use efficiency, while also highlighting key research priorities for future investigation.
