Dense planting is a core strategy for unlocking maize yield potential and ensuring national food security in China. However, under high-density cultivation, conventional planophile maize varieties often suffer from canopy closure, reduced photosynthetic efficiency, and increased lodging risk, which have become limiting factors constraining yield gains from dense planting. Leaf angle, a key agronomic trait that governs canopy architecture, optimizes light distribution within the plant community, enhances radiation use efficiency, and improves lodging resistance, has emerged as a central target in modern molecular breeding of compact maize. Recent advances in maize functional genomics have enabled the cloning of key genes regulating leaf angle, such as ZmTAC1, ZmRAVL1, and ZmILI1, along with the progressive elucidation of their molecular regulatory mechanisms. CRISPR/Cas9-based genome editing, characterized by its precision, high efficiency, capacity for multiplex targeting, and absence of linkage drag, provides a transformative technological platform for the targeted modification of leaf angle and the rapid development of compact germplasm. This review systematically synthesizes the genetic architecture and molecular regulatory networks governing maize leaf angle, with emphasis on the functional dissection of key regulatory genes. We summarize the progress and current challenges in applying both single-gene and multiplex genome editing for the creation of compact germplasm, and discuss future directions in this field. This synthesis aims to provide a reference for the molecular design breeding of next-generation, compact maize varieties in China.

Virus-induced gene silencing (VIGS), a post-transcriptional gene silencing technique, is widely used for the functional characterization of plant genes. To determine whether TRV-mediated VIGS can specifically target genes in Brassica napus and significantly downregulate their expression, thereby improving the efficiency of gene function studies, four genes, including BnaJMJ13 and BnaSNAP33, were selected as target genes in this study. A 300-500 bp core cDNA fragment of each gene was amplified and cloned into the TRV2 vector. Two-day-old germinated seeds of B. napus were then subjected to vacuum infiltration, and leaves and flower buds were collected for RT-qPCR analysis. The results showed that TRV-VIGS significantly reduced the transcript levels of the target genes in both tissues. Phenotypic analysis at the flowering stage showed that plants with downregulated BnaJMJ13 expression flowered significantly earlier, suggesting that BnaJMJ13 functions as a negative regulator of flowering time in B. napus. Semi-in vivo pollination assays revealed that BnaSNAP33 may affect seed setting in B. napus by modulating pollen adhesion and hydration. To further verify the efficiency of TRV-induced gene silencing, loss-of-function mutants of BnaSNAP33 were generated in this study. Semi-in vivo pollination assays further confirmed that BnaSNAP33 regulates seed setting by affecting pollen adhesion and hydration. These results demonstrate the applicability of this silencing system in B. napus. The TRV-VIGS system established in this study is easy to operate, highly efficient, and time-saving, and will facilitate functional genomics research in B. napus.

The lower Yangtze River Region is a major production area for japonica/geng rice in China. Understanding the genetic architecture, indica/xian introgression patterns, and functional genotypes of dominant varieties is essential for accelerating molecular design breeding and germplasm improvement. In this study, whole-genome sequencing, with an average depth of 19.8×, was performed on eight dominant japonica/geng rice varieties from this region to systematically evaluate their genetic relationships, genome-wide indica-type introgression segments, and key functional alleles. Pedigree traceability was further examined using the high-quality variety Huruan 1212 as an example. The results showed that the eight varieties maintained high genetic diversity and representativeness. Genome-wide analysis indicated that indica-type introgression segments were irregularly distributed across the genome, with total lengths ranging from 0 to 4.9 Mb. Notably, Huzaogeng 193 and Xiushui 134 carried the largest number of introgression segments. These indica-derived segments were significantly enriched in pathways associated with disease resistance, stress tolerance, and biomass accumulation. Genotypic analysis revealed that although these varieties had successfully incorporated favorable alleles related to grain quality (ALK and Waxy), stress tolerance (HAN1, OsPP15, and qLTG3-1), and stripe leaf blight resistance (STV11), clear genetic gaps remained. In particular, resistance to rice blast and bacterial diseases still requires further improvement, and the frequencies of favorable alleles for major agronomic traits remain relatively low. Pedigree tracing of Huruan 1212 showed that its genetic background was mainly derived from Nangeng 46, accounting for 39.71%, while also incorporating yield-related genotypes from Jinfeng and indica-derived segments from Dahuaxianggeng. Collectively, these genomic insights provide an important foundation for the molecular breeding of high-yielding and high-quality japonica/geng rice varieties.

Malate dehydrogenase (MDH; EC1.1.1.37) is widely distributed in plants and catalyzes the interconversion of malate and oxaloacetate using NADH or NADPH as cofactors. MDH plays a crucial role in the tricarboxylic acid (TCA) cycle and is involved in regulating various physiological processes, including plant growth, development, and stress responses. In this study, eight MDH family members were identified in the potato genome using bioinformatics approaches. These genes were named StMDH1 to StMDH8 according to their chromosomal locations and were further classified into five subfamilies. Analysis of physicochemical properties showed that the predicted StMDH proteins ranged from 30.11 to 43.85 kD in molecular weight, with isoelectric points ranging from 5.91 to 9.00. Subcellular localization prediction indicated that these proteins are mainly localized in chloroplasts and mitochondria. Gene structure analysis showed that members within the same subfamily had similar exon numbers and conserved motif compositions. Expression profiling based on publicly available transcriptome data revealed that most StMDH genes responded to abiotic stresses and hormone treatments, with StMDH2 showing the strongest salt stress-induced expression pattern. Furthermore, heterologous expression in Saccharomyces cerevisiae confirmed that overexpression of StMDH2 significantly enhanced salt tolerance in yeast cells. This study expands our understanding of the potato MDH gene family and provides potential genetic resources and candidate targets for the molecular breeding of stress-resistant potato varieties.

Based on yield data from the national wheat regional variety trials conducted in the irrigated group of the Northern Winter Wheat Region (NWWR) from 2021 to 2025, this study compared the reliability of genotype plus genotype-by-environment interaction (GGE) biplots constructed from raw data and best linear unbiased prediction (BLUP) values for mega-environment (ME) investigation. In addition, comprehensive evaluation of trial locations and subdivision of ecological subregions were performed using the BLUP-GGE biplot. The results showed that the goodness of fit of the BLUP-GGE biplot was 13.5 percentage points higher than that of the GGE biplot based on raw data, resulting in more accurate and reliable evaluation of test locations. Notably, two spurious MEs identified by the raw data-based GGE biplot were not detected in the BLUP-GGE biplot, highlighting the limitations of traditional GGE biplot analysis for multi-year and multi-location variety trial data. Location evaluation based on the BLUP-GGE biplot showed that Luannan, Hebei, had the best overall performance, followed by Gu’an, Hebei, Baodi, Tianjin, and Zunhua, Hebei, which also performed excellently. Changping, Beijing, Shunyi, Beijing, Wuqing, Tianjin, and Baoding, Hebei, showed favorable performance, whereas Tunliu, Qixian, and Taiyuan in Shanxi showed moderate performance. Ecological subregions delineated using the which-won-where view of the BLUP-GGE biplot differed significantly only in location representativeness, with no significant differences in discriminating ability or desirability index. In contrast, subregions defined using the trial-location clustering view of the BLUP-GGE biplot showed significant differences in all three indices, namely representativeness, discriminating ability, and desirability index, thereby providing a more comprehensive reflection of ecological characteristics and greater practical value. Among these subregions, the first ecological subregion, encompassing all trial locations in Hebei and Tianjin and accounting for more than 60% of the total locations, represented the major ecological subregion of the irrigated group in the NWWR. This subregion had the best representativeness and desirability index, together with favorable discriminating ability, making it an ideal area for regional variety trials. The second ecological subregion, representing the ecological conditions of suburban Beijing, had strong discriminating ability and moderate representativeness and was therefore more suitable for early-stage variety screening. The third ecological subregion, including Tunliu and Qixian in Shanxi province, was characterized by high altitude and a cool climate, resulting in weak discriminating ability and limited suitability for variety evaluation. This study confirms the superiority of the BLUP-GGE biplot in analyzing multi-year and multi-environment variety trial data and proposes a robust method for ecological subregion delineation based on trial-location clustering. These findings provide a scientific basis for optimizing wheat regional trial schemes and supporting the precise recommendation and deployment of varieties in the irrigated group of the NWWR.

Maize common smut, caused by Ustilago maydis, is a widespread disease that seriously threatens maize yield and quality worldwide. Breeding resistant varieties is the most economical and effective strategy for controlling this disease. To identify elite germplasm resistant to common smut and uncover key resistance genes, this study systematically evaluated the resistance levels of 425 maize inbred lines, aiming to dissect the genetic basis of resistance and screen for resistance-related genes. Artificial inoculation and resistance evaluation were conducted in the field at two locations over two years, based on disease index (DI), incidence rate (IR), and area under the disease progress curve (AUDPC). A genome-wide association study (GWAS) was performed using 970,761 high-quality SNPs, and candidate resistance genes were further screened by integrating spatiotemporal transcriptomic data, followed by functional enrichment analysis. Among the 425 inbred lines, 6 were identified as highly resistant, 27 as resistant, 67 as moderately resistant, 154 as susceptible, and 171 as highly susceptible. The broad-sense heritabilities of DI, IR, and AUDPC were all above 75%. GWAS detected a total of 1665 significantly associated SNP loci, leading to the identification of 376 candidate genes, among which 79 were differentially expressed in response to pathogen infection and 19 were significantly upregulated. GO enrichment analysis indicated that the candidate genes were mainly involved in processes such as defense response, cell wall organization, and hormone signaling. This study confirms that resistance to maize common smut is highly heritable and controlled by multiple genes. The resistance-associated loci and candidate genes identified here provide important germplasm resources and genetic targets for the molecular breeding of maize varieties resistant to common smut.

The genetic transformation efficiency of Brassica napus is severely constrained by callus differentiation capacity, which varies greatly among genotypes. In this study, transcriptome analysis was performed at two key time points to elucidate the molecular mechanisms underlying differences in callus differentiation capacity, thereby providing a theoretical basis and genetic resources for genetic improvement. Two representative materials with highly significant differences in callus differentiation capacity, ZP10 with high differentiation capacity and ZP15 with low differentiation capacity, were selected from 20 B. napus genotypes. Transcriptome sequencing and comparative analysis were conducted on calli from these two lines at 0 and 30 days after induction (DAI). A total of 1915 genes were identified through differentially expressed gene (DEG) screening. GO and KEGG enrichment analyses showed that these genes were significantly enriched in pathways related to plant hormone signal transduction, photosynthesis-antenna proteins, photosynthetic organ assembly, and cell wall biosynthesis. Combined with weighted gene co-expression network analysis (WGCNA), 25 key candidate genes were ultimately identified, and their expression patterns were closely associated with high differentiation capacity. The reliability of the transcriptome data was confirmed by qRT-PCR. In conclusion, the high callus differentiation capacity of B. napus is associated with a complex regulatory network coordinated by multiple genes and involving hormone signaling responses, initial establishment of the photosynthetic system, and cell wall remodeling. The key genes identified in this study provide important targets for further elucidating the molecular mechanisms underlying rapeseed regeneration and for breeding genotypes with high transformation efficiency.

This study aimed to elucidate the heterosis and inheritance patterns of major phenotypic traits and fatty acid contents in F₁ interspecific hybrids derived from Coix lacryma-jobi var. maxima Makino×Coix chinensis var. chinensis, thereby providing a foundation for interspecific introgression breeding and heterosis utilization in adlay. Five cross combinations were developed using the common male parent CL91 and five local varieties as female parents, and mid-parent heterosis and higher-parent heterosis were calculated for major agronomic traits, involucre traits, and free fatty acid contents. Cluster analysis based on 13 phenotypic traits showed that four F₁ hybrids, JZCL, JFCL, JNCL, and BCL, were morphologically more similar to their female parents, whereas WYCL more closely resembled the male parent. For the eight agronomic traits, mid-parent heterosis and higher-parent heterosis ranged from -30.6% to 90.2% and from -48.1% to 77.3%, respectively. Overall, most cross combinations showed positive mid-parent heterosis, whereas only a few exhibited higher-parent inheritance for specific traits. For the five involucre traits, mid-parent heterosis and higher-parent heterosis ranged from -5.3% to 52.7% and from -32.7% to 9.5%, respectively. Involucre size and shape generally fell between those of the male and female parents, with predominantly positive mid-parent heterosis, whereas higher-parent heterosis was consistently negative. A total of 22 free fatty acids were detected in adlay seeds, including 8 unsaturated and 14 saturated fatty acids. Linoleic acid (C18-2n6c), oleic acid (C18-1n9c), palmitic acid (C16-0), and stearic acid (C18-0) were the most abundant fatty acids and varied significantly among the five F₁ hybrids and their parents. The hybrids JNCL and WYCL exhibited pronounced heterosis and higher-parent inheritance for multiple fatty acids and total fatty acid content, whereas JZCL, JFCL, and BCL showed relatively weak heterosis for fatty acid content. The interspecific hybrids of Coix lacryma-jobi var. maxima Makino×Coix chinensis var. chinensis exhibited broad mid-parent heterosis in plant morphology and developmental traits, such as plant height and grain layer number, indicating that F₁ plants were generally more vigorous under the “subtropical/tropical×temperate” crossing pattern. In addition, JNYM and WY02 could serve as valuable parental lines for fatty acid improvement in adlay breeding programs.

The continuous expansion of saline-alkali land poses a serious challenge to crop production. Exploring salt-tolerant germplasm resources in adzuki bean and elucidating the underlying molecular mechanisms of salt tolerance are of great significance for expanding the suitable planting area of adzuki bean and ensuring food security. In this study, 110 adzuki bean germplasm resources were used as experimental materials. Based on membership function analysis and principal component analysis (PCA), 11 growth indices were reduced to three comprehensive indices. Accordingly, the salt-tolerant cultivar Dongzhangxiaohongdou and the salt-sensitive cultivar Tehong 3 were identified. Physiological and biochemical analyses showed that Dongzhangxiaohongdou exhibited significantly stronger antioxidant capacity and osmotic adjustment ability than Tehong 3. Transcriptome analysis identified 3801 and 7811 differentially expressed genes (DEGs) in salt-treated Dongzhangxiaohongdou and Tehong 3, respectively, compared with their corresponding control groups. Gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) enrichment analyses showed that these DEGs were mainly involved in biological processes such as metabolic pathways and cellular processes. Integrated transcriptomic analysis and quantitative real-time PCR (qRT-PCR) validation further identified three putative salt tolerance-associated genes, LOC108343245, LOC108346293, and LOC108331871, which were primarily involved in starch and sucrose metabolism pathways. This study successfully identified salt-tolerant adzuki bean germplasm resources and suggests that the identified salt-responsive genes may regulate salt tolerance in adzuki bean through starch and sucrose metabolism. These findings provide a theoretical foundation for breeding new salt-tolerant adzuki bean varieties and promoting the rational utilization of saline-alkali soils.

The RNA polymerase II-associated factor 1 (Paf1) complex is a conserved transcriptional regulator in eukaryotes; however, whether Paf1 plays a role in plant antiviral responses remains unclear. Wheat is one of the natural hosts of barley stripe mosaic virus (BSMV). In this study, analysis of gene expression showed that wheat Paf1 subunit genes are transcriptionally responsive to BSMV infection. Based on the principle of virus-induced gene silencing (VIGS), we engineered BSMV-derived viral clones capable of inducing silencing of distinct host Paf1 subunit genes during infection of wheat. In wheat seedlings infected with these clones, silencing of each Paf1 subunit gene enhanced BSMV-triggered hypersensitive response (HR)-associated cell death. Furthermore, comparative analysis of viral proliferation in wheat seedlings and adult plants infected with either a control BSMV clone or an engineered clone designed to silence the Paf1 subunit gene TaCDC73 revealed that TaCDC73 silencing reduced viral accumulation. These results indicate that TaCDC73 silencing potentiates the antiviral response in BSMV-infected wheat plants. In addition, plants infected with the TaCDC73-silencing BSMV clone exhibited more pronounced growth inhibition than those plants infected with the control BSMV clone. Collectively, our findings demonstrate that the Paf1 complex functions as a negative regulator of resistance to BSMV by suppressing HR-associated cell death. This regulatory role of Paf1 may help maintain the growth-defense balance by preventing hyperactivation of immune responses during BSMV infection.

C2H2-type zinc finger proteins play crucial regulatory roles in plant growth, development, and stress responses. Based on previous transcriptome data under cold stress, a C2H2-type zinc finger protein gene, PaZFP36, was cloned from Pennisetum alopecuroides cv. ‘Liqiu’ in this study. Bioinformatic analysis was performed, and overexpression vectors were constructed and transformed into Arabidopsis thaliana and P. alopecuroides cv. ‘Liqiu’. Photosynthetic characteristics and agronomic traits at maturity were systematically analyzed through pot experiments. The results showed that the PaZFP36 protein has a molecular weight of 24.65 kD and an isoelectric point of 8.49 and contains two typical C2H2 zinc finger domains. Overexpression of PaZFP36 in both Arabidopsis and P. alopecuroides cv. ‘Liqiu’ significantly increased the net photosynthetic rate (P_n), maximum photochemical efficiency (F_v/F_m), and photosynthetic performance index (PI_abs), while significantly decreasing the intercellular CO₂ concentration (C_i). These results indicate that PaZFP36 synergistically enhances photosynthetic efficiency by improving mesophyll CO₂ fixation capacity, optimizing PSII reaction center performance, and enhancing electron transport chain efficiency. Compared with wild-type plants, PaZFP36-overexpressing lines of both Arabidopsis and P. alopecuroides cv. ‘Liqiu’ exhibited significantly increased plant height, fresh weight, dry weight, and main root length. In addition, transgenic Arabidopsis showed significant increases in pod length and pod number per main stem, whereas transgenic P. alopecuroides cv. ‘Liqiu’ showed a significant increase in tiller number. Correlation analysis revealed a significant positive relationship between net photosynthetic rate and dry weight. In conclusion, overexpression of PaZFP36 enhances photosynthetic efficiency and promotes biomass accumulation and yield formation in P. alopecuroides cv. ‘Liqiu’, providing germplasm resources and a theoretical basis for breeding stress-tolerant and high-yielding Pennisetum varieties.

The wheat landrace Xiaoganmai (ZM011362), originating from Dangyang, Hubei Province, exhibits multiple desirable traits, including multi-floret and high-grain-number characteristics, numerous effective tillers, stable pre-harvest sprouting resistance, and adult-plant resistance to stripe rust, making it a potentially valuable germplasm resource for modern wheat breeding. In a previous study, 178 Shumai 753/Xiaoganmai-derived lines were developed using Xiaoganmai as the donor parent and the elite breeding line Shumai 753, which carries all-stage stripe rust resistance genes and shows good overall agronomic performance, as the recurrent parent through hybridization, backcrossing, continuous multi-generation selfing, and a segmented target-trait selection strategy. This study aimed to dissect the genetic basis of the Shumai 753/Xiaoganmai-derived lines at the molecular level, identify key chromosomal regions controlling yield, disease resistance, and stress tolerance, and provide molecular evidence for the genetic improvement of wheat using landraces. Whole-genome scans of Xiaoganmai, Shumai 753, and their 178 derivative lines were performed using the wheat 55K liquid SNP array, and a total of 52,779 valid homozygous polymorphic SNP loci were obtained. Genetic similarity and genetic composition of the parents and derivative lines were analyzed based on these polymorphic SNP loci. The genetic similarity coefficient between the two parents was only 0.44, indicating substantial genetic divergence between Xiaoganmai and Shumai 753 at the molecular level. Analysis of the genetic similarity and composition of the derivative lines showed that their whole-genome molecular profiles were largely consistent with their pedigree background, with no obvious bias in parental inheritance. Based on marker-trait genome-wide association analysis, 127 chromosomal regions or loci significantly associated with plant height (14), spike length (12), spikelet number per spike (21), effective tiller number (20), thousand-grain weight (25), and relative seed germination index (35) were identified. Analysis of parental genetic contributions revealed that the proportions of SNP loci inherited from Xiaoganmai and Shumai 753 in the derivative lines ranged from 7.88% to 43.95% and from 56.05% to 92.12%, with average proportions of 26.45% and 73.55%, respectively. In total, 86 and 259 high-frequency selected regions derived from Xiaoganmai and Shumai 753, respectively, with sizes ranging from 0.01 to 108.75 Mb and contribution rates ≥80%, were identified in the derivative lines and were unevenly distributed across the 21 wheat chromosomes. Combined with the genome-wide association mapping results, 43 high-frequency selected chromosomal regions derived from Xiaoganmai and Shumai 753 were significantly associated with plant height, spike length, spikelet number per spike, effective tiller number, thousand-grain weight, and relative seed germination index. Among these regions, 16 simultaneously controlled two or more traits, indicating pleiotropic effects. Further analysis of the genetic composition of high-frequency selected chromosomal regions in 14 elite derivative lines revealed that the preferential transmission of regions significantly associated with important yield-related traits, together with their targeted selection as key loci, underlies the successful utilization of the landrace Xiaoganmai to improve the yield structure of Shumai 753 and ultimately achieve coordinated improvement in yield, disease resistance, and stress tolerance.

To achieve coordinated improvement in yield and nutritional quality, the GGE (genotype+genotype×environment interaction) biplot method was employed to systematically dissect the genetic differences, environmental adaptability, and trait stability of potato yield and flavonoid content across different ecological regions. The core objective was to screen elite genotypes with high yield, high flavonoid content, and stability adapted to specific ecological zones, thereby providing theoretical support for breeding nutritionally enhanced potato varieties. A total of 130 potato varieties (lines) were tested in a two-year (2021-2022), 3-location trial conducted in three ecological regions of Gansu province: Weiyuan county, Anding district, and Yongchang county. Plot yield and contents of catechin, rutin, nicotiflorin, quercetin, and kaempferol were measured after harvest. Joint analysis of variance and GGE biplot were used to analyze the genotype×environment interaction for yield and quality traits. The ANOVA showed that, except for plot yield which had no significant year effect, the effects of genotype, environment, and genotype×environment interaction were highly significant (P < 0.01) for all traits. Plot yield, catechin content, and rutin content were mainly influenced by genotype, whereas nicotiflorin, quercetin and kaempferol contents were predominantly affected by genotype×environment interaction. GGE analysis for plot yield indicated that G122 had the highest yield at Anding (2021, 2022), Weiyuan (2022), and Yongchang (2022). G27 had the highest yield at Yongchang in 2021, G36 had the highest yield at Weiyuan in 2021. C18, G122, C6, G102, G42, G49, C3, and G9 were high-yielding and stable. The discriminative power of test locations ranked as Yongchang > Anding > Weiyuan, with the Anding being the most representative. GGE analysis of flavonoid content revealed that G79 had the highest catechin content across all three locations, the highest kaempferol content at Anding and Weiyuan, and the highest nicotiflorin content at Yongchang. C16 had the highest rutin and nicotiflorin contents at Anding and Weiyuan. G37, G4, and G46 had the highest rutin, quercetin, and kaempferol contents, respectively, at Yongchang. G32 had the highest quercetin content at Anding and Weiyuan. G98, G63, G1, G129, and G102 had high and stable catechin content. G37, G113, G49, C11, and G93 had high and stable rutin content. G37, G122, G13, and G21 had high and stable nicotiflorin content. G46, G71, G124, and G79 had high and stable quercetin content. G9, C5, and G27 had high and stable kaempferol content. The discriminative power of test locations ranked as Yongchang > Weiyuan > Anding, with the Yongchang being the most representative for flavonoid traits. Using the GGE model combining plot yield and flavonoid content, elite lines (G122, G102, G49, and G93) were identified as high-yielding, high in flavonoid content, and stable. Considering both discriminatory power and representativeness, Anding is recommended as an ideal environment for yield evaluation, while Yongchang is more suitable for screening varieties (lines) for both yield and flavonoid content under specific environments.

To investigate the functions of the soybean GmbHLH119 and GmbHLH120 genes, this study performed bioinformatic analyses, subcellular localization, and expression profiling in different soybean tissues under nitrogen and phosphorus treatments. The results showed that GmbHLH119 and GmbHLH120 share a high degree of structural similarity. Preliminary expression analysis revealed that both genes were relatively highly expressed in soybean leaves. Promoter analysis identified multiple cis-acting elements related to light responsiveness, hormone responsiveness, and abiotic stress responsiveness in the promoter regions of GmbHLH119 and GmbHLH120. Both proteins contain a conserved HLH domain and were predicted to be unstable hydrophilic proteins with highly conserved structures. Subcellular localization assays showed that both GmbHLH119 and GmbHLH120 are localized in the nucleus. In addition, their expression patterns under different nitrogen and phosphorus treatments suggested that these two genes may participate in regulating soybean responses to changes in nitrogen and phosphorus availability. Overall, this study provides a theoretical basis for further functional characterization of GmbHLH119 and GmbHLH120 in soybean.

This study investigated the responses of root and leaf architecture, canopy light utilization, and grain-filling characteristics to increased planting density in maize cultivars with varying density tolerance. A two-factor field experiment was conducted during the 2023 and 2024 maize growing seasons using three maize cultivars differing in density tolerance: Xianyu 335 (XY335), Zhengdan 958 (ZD958), and MY73. Five planting density treatments were established: 60,000 (D1), 75,000 (D2), 90,000 (D3), 105,000 (D4), and 120,000 plants hm^-2 (D5). Traits related to root-leaf architecture, canopy light distribution, leaf photosynthetic parameters, leaf area, photosynthetically active radiation use efficiency, and grain filling were measured. The results showed that XY335, ZD958, and MY73 achieved high yields at D1-D2, D2-D3, and D3-D4, respectively, with their optimum density ranges centered around D1, D2, and D3. Across all density treatments in the two-year experiment, the density-tolerant cultivar MY73 had significantly greater root angle, root projected area, root number, root-shoot ratio, leaf orientation value, light transmittance in each canopy layer, and net photosynthetic rate under high density than ZD958 and XY335, whereas its leaf area and dry matter radiation use efficiency were significantly lower. At low densities, XY335 had significantly higher yield and grain radiation use efficiency than ZD958 and MY73, whereas under high-density conditions, MY73 significantly outperformed XY335 and ZD958. With increasing density, root biomass, root-shoot ratio, root architecture, leaf angle, light transmittance in each canopy layer, and leaf area at different leaf positions decreased significantly across cultivars, while leaf orientation value and dry matter radiation use efficiency increased significantly. Potential grain weight and the maximum grain-filling rate showed decreasing trends, whereas the time to reach the maximum grain-filling rate and the active grain-filling period increased. Cultivars with different density tolerance exhibited different magnitudes of trait variation in response to increased density. Among the three cultivars, the density-tolerant MY73 showed the smallest reductions in root projected area and root weight, with two-year mean reductions that were 3.9% and 16.1% lower than those of ZD958 and 4.4% and 0.6% lower than those of XY335, respectively. MY73 also showed a smaller reduction in leaf angle in the ear-leaf layer and a greater increase in leaf orientation value; the mean reduction in leaf angle was 3.0%-47.9% lower than that of ZD958, while the mean increase in leaf orientation value was 14.0%-357.5% greater. MY73 exhibited the smallest reduction in light transmittance in each canopy layer; its two-year mean reduction was 37.0% and 46.9% lower than that of ZD958 and XY335, respectively, at the midpoint between the canopy top and ear position, and 32.4% and 49.6% lower at the ear position. The leaf area in the upper canopy was the most sensitive to increased density across cultivars, and the two-year mean reduction in MY73 was 22.1% and 32.3% lower than that in ZD958 and XY335, respectively. In conclusion, the density-tolerant cultivar MY73 showed less deterioration in root traits, stronger regulation of leaf orientation, more favorable canopy light transmittance, higher leaf net photosynthetic rate under high density, and a smaller reduction in individual plant leaf area as density increased. It also maintained a shorter time to reach the maximum grain-filling rate, a longer active grain-filling period, and higher grain radiation use efficiency under high-density conditions. These characteristics may represent the population quality regulation mechanism underlying the high yield of MY73 under dense planting.

Remote sensing-based diagnosis of crop leaf nitrogen concentration (LNC) is of great importance for guiding precise nitrogen application, improving nitrogen use efficiency, and increasing crop yield. To address the limitations of the traditional successive projections algorithm (SPA) in handling nonlinear relationships among spectral features, this study proposes an improved successive projections algorithm, namely the kernel successive projections algorithm (KSPA). Continuous wavelet transform (CWT) was used for multi-scale spectral decomposition, and KSPA was subsequently applied to extract key features associated with LNC. For comparison, vegetation indices, SPA, and partial least squares-variable importance in projection (PLS-VIP) were also used for feature selection. Models based on partial least squares regression (PLSR), random forest (RF), and categorical boosting (CatBoost) were constructed to estimate winter wheat LNC, and Shapley additive explanations (SHAP) were used for model interpretability analysis. The results showed that intermediate CWT decomposition scales performed well in estimating winter wheat LNC, and the features selected by KSPA significantly improved model performance. The CatBoost model combined with KSPA at the seventh CWT scale achieved the best performance (R² = 0.829, RMSE = 0.322%, RPD = 2.425). Compared with the best models based on PLS-VIP (RF: R² = 0.729, RMSE = 0.405%) and SPA (CatBoost: R² = 0.731, RMSE = 0.403%), this model increased R² by 0.100 and 0.098 and reduced RMSE by 0.083% and 0.081%, respectively. Leave-one-year-out cross-validation further confirmed the robustness and generalization ability of the proposed method. Overall, the improved algorithm effectively overcomes the linear limitations of traditional SPA in feature selection and provides a useful reference for precision monitoring of nitrogen nutrition in winter wheat.

To investigate the effects of tillage methods and soil amendments on soil physicochemical properties and grain yield formation in low-fertility summer maize fields, a field experiment was conducted during the 2023-2024 summer maize growing seasons in Taiping village, Wangzhuang town, Feicheng city, Shandong province, China. The summer maize cultivar Zhenghuangnuo 2 was used as the experimental material, and a split-plot design was adopted. The main plots consisted of two tillage methods: rotary tillage to 15 cm (RT) and subsoiling to 30 cm combined with rotary tillage to 15 cm (SRT). The subplots consisted of six amendment treatments under equal nitrogen, phosphorus, and potassium inputs: compound fertilizer at 750 kg hm^-2 (F); compound fertilizer plus water-retaining agent at 60 kg hm^-2 (FW); compound fertilizer plus humic acid at 1500 kg hm^-2 (FH); compound fertilizer plus humic acid at 1500 kg hm^-2 and water-retaining agent at 60 kg hm^-2 (FHW); compound fertilizer plus organic fertilizer at 15 t hm^-2 (FO); and compound fertilizer plus organic fertilizer at 15 t hm^-2 and water-retaining agent at 60 kg hm^-2 (FOW). The regulatory effects of these treatments on soil total porosity, three-phase ratio, water potential, organic matter, and nutrient contents, as well as their effects on maize growth, development, and yield formation in low-fertility summer maize fields, were evaluated. Compared with RT, SRT significantly increased soil total porosity, total nitrogen, and total phosphorus contents in the 0-20 cm soil layer by 8.57%, 9.30%, and 14.71%, respectively, and significantly increased soil organic matter content in the 0-20 and 20-40 cm soil layers by 11.27% and 14.55%, respectively. Soil amendments significantly increased total porosity, water potential, and gas- and liquid-phase proportions in the 0-20 cm soil layer, thereby improving soil aeration and water-holding capacity. They also increased soil organic matter content, promoted nutrient supply, and ultimately enhanced maize dry matter accumulation and grain yield. Among the amendment treatments, FHW was the most effective in improving soil physicochemical properties and produced the greatest increase in grain yield. Compared with the control, FHW increased aboveground dry matter accumulation and grain yield by two-year averages of 24.57% and 26.44%, respectively. In conclusion, SRT combined with compound fertilizer, humic acid, and a water-retaining agent (FHW) can serve as an effective measure for improving soil physicochemical properties and increasing summer maize grain yield in low-fertility farmland.

To address the urgent need for nitrogen (N) fertilizer reduction in the sustainable silage maize production in the Hexi oasis irrigation area, while mitigating the associated decline in forage yield and quality, under reduced N conditions, this study investigated the effects and compensatory mechanism of intercropping with leguminous forages on the yield and quality of silage maize under nitrogen-reduced conditions, aiming to provide a scientific basis for the sustainable production of silage maize in this region. The experiment was conducted in 2023-2024 at the Wuwei Oasis agricultural comprehensive experimental station using a split-plot design. The main plots consisted of three planting patterns: monocropped silage maize (M), silage maize-millet bean intercropping (MH), and silage maize-lablab bean intercropping (ML). The subplots included four nitrogen application rates: conventional nitrogen application (N3, 360 kg hm^-2), 15% nitrogen reduction (N2, 306 kg hm^-2), 30% nitrogen reduction (N1, 252 kg hm^-2), and no nitrogen application (N0, 0 kg hm^-2). The results showed that under 30% nitrogen reduction (N1), compared to monoculture (M), the MH and ML patterns increased crude protein content by 24.7% and 27.6%, starch content by 35.6% and 37.3%, and crude ash content by 26.5% and 72.2%, respectively, neutral detergent fiber content decreased by 11.9% and 14.0%, the acid detergent fiber content decreased by 10.5% and 14.9%, and the relative feed value increased by 18.6% and 22.3%, respectively. Under N1, dry matter accumulation and forage yield of silage maize in the MH and ML were significantly higher than in M, with dry matter accumulation increasing by 18.8% (MH) and 31.5% (ML) and the forage yield by 28.9% (MH) and 45.2% (ML), respectively. Furthermore, under N1, the MH and ML patterns exhibited compensatory effects for crude protein, starch, crude ash, RFV and forage yield compared to the conventional nitrogen monoculture (N3+M), with ML showing stronger compensation than MH. Therefore, silage maize-lablab bean intercropping combined with a nitrogen application rate of 252 kg hm^-2 (30% reduction) can improve both forage quality and yield, representing a suitable planting pattern and nitrogen application rate for sustainable silage maize production in the oasis irrigation area.

This study investigated the effects of different nitrogen-potassium ratios under equal total nutrient input on sweet potato yield, quality, and nutrient uptake and utilization, aiming to provide a scientific basis for balanced mineral fertilization to achieve high yield, high quality, and high efficiency in sweet potato production. A two-year field experiment was conducted using a split-plot design in Hechuan District, Chongqing, China, during the 2023 and 2024 growing seasons. Two sweet potato cultivars, Yuhongxinshu 98 (Yhs98) and Yuhongxinshu 3 (Yhs3), were assigned to the main plots, and five N:K₂O ratio treatments under equal total nutrient input were assigned to the subplots: R1 (1:3), R2 (1:1.5), R3 (1:1), R4 (1.5:1), and R5 (3:1). The effects of these N:K₂O ratios on storage root yield and quality, photosynthetic characteristics and carbon-nitrogen metabolic enzyme activities in functional leaves, plant biomass accumulation, and nutrient uptake and utilization were systematically evaluated. The results showed that storage root yield, number of storage roots per plant, single storage root weight, starch and soluble sugar contents in storage roots, photosynthetic parameters, activities of key carbon-nitrogen metabolic enzymes in functional leaves, T/R value, and dry weight and nitrogen (N) and potassium (K) accumulation in storage roots were higher under the R1 or R2 treatments than under the other treatments. In contrast, soluble protein content in storage roots, vine dry weight, and N and K accumulation in vines were higher under the R4 or R5 treatments. The long-vine cultivar was more sensitive to changes in the N:K₂O ratio. Compared with the R5 treatment, R2 increased storage root yield by 31.01% and 35.87% and nitrogen use efficiency (NUE) by 157.63% and 89.25% in Yhs98 and Yhs3, respectively. Compared with the R1 treatment, R2 increased potassium use efficiency (KUE) by 47.67% and 100.56% in Yhs98 and Yhs3, respectively. In conclusion, the R2 treatment (N:K₂O = 1:1.5) synergistically optimized photosynthetic performance and the activities of key carbon-nitrogen metabolic enzymes in sweet potato functional leaves, promoted the efficient partitioning of photosynthates to storage roots, achieved simultaneous improvements in storage root yield and quality, and increased both NUE and KUE. Therefore, R2 was the optimal N:K₂O nutrient ratio under the conditions of this study.

In soybean-maize strip intercropping systems, the mechanisms by which the maize nitrogen-density interaction regulates canopy light-resource competition and allocation and coordinates yield formation in maize and soybean remain unclear. To address this issue, a two-year split-plot field experiment was conducted from 2023 to 2024 in the summer soybean-summer maize strip intercropping region of the Huang-Huai-Hai Plain. The treatments consisted of three maize planting densities, D1: 5.25×10⁴ plants hm^-2, D2: 6.75×10⁴ plants hm^-2, and D3: 8.25×10⁴ plants hm^-2, and four nitrogen application rates, namely N0, N120, N240, and N360 in 2023, corresponding to 0, 120, 240, and 360 kg hm^-2 N, and N0, N240, N300, and N360 in 2024, corresponding to 0, 240, 300, and 360 kg hm^-2 N. Canopy light interception, leaf growth and senescence, photosynthetic potential, and yield were systematically analyzed to elucidate the regulatory effects of the nitrogen-density interaction on canopy light interception and system yield. The results showed that increasing maize planting density significantly enhanced light interception by the maize canopy, but excessive density, D3, accelerated leaf senescence, whereas appropriate nitrogen application, 240-300 kg hm^-2 N, effectively delayed senescence. Compared with D1, D2 increased the light interception rate of the upper maize canopy by an average of 31.28% and also increased the leaf area index (LAI) and total photosynthetic potential. In contrast, D3 intensified intraspecific light competition and markedly increased the senescence index. Compared with the corresponding low-density controls, D2N240 in 2023 and D2N300 in 2024 increased the upper-canopy light interception rate by 5.56% and 28.80%, respectively, and significantly improved LAI and total photosynthetic potential. The light interception rate, LAI, and photosynthetic potential of strip-intercropped soybean were inhibited by increasing maize density, although appropriate nitrogen application partially alleviated this inhibition. Compared with D1, D3 reduced the light interception rate of border-row soybean by an average of 5.10%. Under appropriate nitrogen application, 240-300 kg hm^-2 N, the light interception rate of border-row soybean under N240 in 2023 and N300 in 2024 increased by 3.92% and 10.70%, respectively, compared with no nitrogen application. However, soybean growth remained severely inhibited under D3. Compared with the corresponding high-density treatments, D2N240 in 2023 and D2N300 in 2024 significantly alleviated the reductions in light interception rate, LAI, and total photosynthetic potential of border-row soybean. The combination of medium density, D2, and appropriate nitrogen application, 240-300 kg hm^-2 N, achieved a synergistic improvement in maize yield and system yield. Compared with the corresponding low-density controls, D2N240 in 2023 and D2N300 in 2024 increased maize yield by 15.86% and 27.07% and system yield by 7.19% and 16.05%, respectively. Correlation analysis showed that maize yield was highly significantly and positively correlated with light interception rates in the upper and middle canopy layers and with total photosynthetic potential throughout the growth period, whereas soybean yield was mainly determined by canopy light interception at the maize silking stage. Therefore, in maize-soybean strip intercropping systems in the Huang-Huai-Hai Plain, a maize planting density of 6.75×10⁴ plants hm^-2 combined with a nitrogen application rate of 240-300 kg hm^-2 N can synergistically enhance system productivity. This improvement is achieved by optimizing maize canopy structure through the nitrogen-density interaction, delaying leaf senescence, alleviating shading stress on soybean, and coordinating intraspecific and interspecific competition for light resources. These findings provide a theoretical basis and technical support for high-yield and high-efficiency cultivation centered on canopy light-resource regulation in this region.

To screen suitable alkali-resistant hybrid maize varieties, two soil treatments, alkaline soil and control soil, were established in this study. A total of 10 indicators, including plant height, SPAD value, stem diameter, and total fresh weight, were measured in 40 hybrid maize varieties to systematically evaluate alkali tolerance at the seedling stage, and key indicators for alkali resistance evaluation were further identified using stepwise regression analysis. The results showed that all 10 measured indicators were significantly affected by alkali stress, and strong correlations were observed among some indicators. Based on membership function analysis and hierarchical clustering, the 40 hybrid maize varieties were classified into five groups. Among them, varieties such as YK338 and YD903 were identified as highly alkali-resistant, whereas DK653, TL1, XY335, and GY351 were extremely alkali-sensitive. Furthermore, a prediction model for alkali-resistant in maize seedlings was established using stepwise regression analysis, and total fresh weight, root dry weight, total dry weight, and stem diameter were identified as core indicators for evaluating alkali resistance in maize seedlings (R² = 0.99). Analysis of extreme varieties showed that alkali-resistant maize varieties maintained significantly better growth performance than sensitive varieties under alkali stress. These alkali-resistant varieties enhanced their resistance by maintaining lower sodium ion (Na⁺) content, higher potassium ion (K⁺) content, and more efficient uptake of nitrogen (N) and phosphorus (P). In conclusion, this study established a comprehensive evaluation system for alkali resistance in maize under soil culture conditions. The alkali-resistant varieties and core evaluation indicators identified here provide a theoretical basis and technical support for alkali-resistant maize breeding and the efficient utilization of saline-alkali land.

This study aimed to analyze the phenotypic performance of potato genotypes across years and environments, clarify the effects of genotype-by-environment (G×E) interactions, and identify superior and stable genotypes for key traits, together with their suitable environments, thereby providing a basis for targeted breeding and rational variety deployment in specific regions. Seventeen potato varieties were used as test materials and cultivated from 2023 to 2025 at three sites in Qingquan town, Weiqi town, and Huocheng town, Shandan county, Zhangye city, Gansu province. Plant traits, including plant height, stem diameter, and number of main stems, as well as tuber yield components, including number of tubers per plant, tuber weight per plant, and plot yield, were evaluated. Genotype adaptability and stability, together with the discriminating ability and representativeness of test environments, were first assessed using combined ANOVA and GGE biplot analysis, followed by comprehensive selection using the multi-trait stability index (MTSI). Combined analysis of variance revealed significant differences among genotypes, years, and test sites for all measured agronomic and yield traits, except stem diameter. Genotype effects and their interactions with years and sites were the main sources of phenotypic variation. Among the genotype effects, the number of tubers per plant contributed the most to variation, accounting for 50.04%, followed by tuber weight per plant (36.72%) and plot yield (20.92%). Among the interaction effects, the genotype × year × test site interaction explained the largest proportion of variation in stem diameter (36.85%), followed by number of stems (27.35%), plot yield (25.89%), and tuber weight per plant (25.04%). GGE biplot and MTSI analyses identified Atlantic (CK), Longshu 23, and Zhongshu 18 as superior and stable genotypes for key traits, including plant height and yield. Environmental evaluation identified Qingquan town and Huocheng town as the most discriminating and representative test environments for genotype assessment. In addition, the overall discriminating ability of the test sites improved from 2023 to the 2024-2025 period. These results indicate that GGE biplot and MTSI analyses can effectively identify superior genotypes and select optimal trial environments. In particular, Atlantic and Longshu 23 showed both high performance and strong stability across key traits, while the Qingquan and Huocheng sites in the 2024-2025 trials represented ideal environments for reliable variety evaluation and targeted promotion.