Ecological Genetics and Genomics最新文献

Genetic erosion driven by inbreeding and introgressive hybridization in the endemic Manyara tilapia (Oreochromis amphimelas) from Tanzania's saline Rift Valley lakes 来自坦桑尼亚大裂谷盐碱湖的地方性曼雅拉罗非鱼（Oreochromis amphimelas）的近亲繁殖和渐进杂交导致的遗传侵蚀

Q3 Agricultural and Biological Sciences

Ecological Genetics and Genomics

Pub Date : 2026-02-05 DOI: 10.1016/j.egg.2026.100451

Hadija Hussein Said, Cyrus Rumisha

The endemic Manyara tilapia (Oreochromis amphimelas), confined to Tanzania's saline Rift Valley lakes (SRVLs), occurs in small, geographically isolated populations. This limited distribution, combined with recurrent droughts and intense fishing pressure, increases its vulnerability to inbreeding and genetic erosion. The introduction of non-native Nile tilapia (O. niloticus) into some SRVLs further risks introgressive hybridization. Despite these threats, information on the genetic status of Manyara tilapia in SRVLs remains scarce. In this study, we genotyped seven microsatellite loci in 123 individuals of both O. amphimelas and O. niloticus sampled from three SRVLs to test two hypotheses: (i) that O. amphimelas populations exhibit elevated inbreeding, and (ii) that introgressive hybridization has occurred between the two species. The results showed that O. amphimelas had lower genetic diversity and higher inbreeding (F_IS) across all sampled SRVLs than O. niloticus, which exhibited non-significant F_IS in all lakes except Lake Kitangiri. STRUCTURE and snapclust analyses identified two distinct genetic clusters corresponding to the two species in each lake, with most individuals clearly assigned to their respective clusters. However, several individuals in Lake Kitangiri exhibited intermediate ancestry proportions from both species, indicating ongoing hybridization. Because no populations of O. amphimelas exist outside the Tanzanian SRVLs to replenish genetic diversity, continued inbreeding and hybridization may progressively erode the species' evolutionary potential, ultimately leading to its extinction. We recommend preventing the further spread of O. niloticus into uninvaded SRVLs and safeguarding dry-season refugia by designating them as exclusion zones or implementing temporary fishing closures during the dry season.

地方性的Manyara罗非鱼（Oreochromis amphimelas）局限于坦桑尼亚的裂谷盐碱湖（SRVLs），发生在地理上孤立的小种群中。这种有限的分布，再加上经常性干旱和巨大的捕捞压力，增加了其近亲繁殖和遗传侵蚀的脆弱性。将非本土尼罗罗非鱼（O. niloticus）引入一些SRVLs进一步增加了渐进杂交的风险。尽管存在这些威胁，但关于SRVLs中曼雅拉罗非鱼遗传状况的信息仍然很少。在这项研究中，我们对从三个SRVLs中取样的123只O. amphimelas和O. niloticus的7个微卫星位点进行了基因分型，以验证两个假设：(i) O. amphimelas种群表现出较高的近交，（ii）两个物种之间发生了渐渗杂交。结果表明：水獭的遗传多样性较低，近交率较高；除基塔吉里湖外，其他湖泊水獭的近交率均不显著；结构和聚类分析确定了两个不同的遗传集群对应于每个湖泊的两个物种，大多数个体明确地分配到各自的集群。然而，Kitangiri湖的一些个体显示出来自两个物种的中间祖先比例，表明正在进行杂交。由于在坦桑尼亚srvl之外没有两栖动物种群来补充遗传多样性，持续的近亲繁殖和杂交可能会逐渐侵蚀该物种的进化潜力，最终导致其灭绝。我们建议防止niloticus进一步扩散到未入侵的SRVLs，并通过将其指定为禁区或在旱季实施临时休渔区来保护旱季避难所。

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引用次数: 0

Unraveling the phylogeny of seagrass species in Seriwe Bay, Lombok, Indonesia: Evidence from rbcL gene 解开印尼龙目岛塞里湾海草物种的系统发育：来自rbcL基因的证据

Q3 Agricultural and Biological Sciences

Ecological Genetics and Genomics

Pub Date : 2026-01-22 DOI: 10.1016/j.egg.2026.100450

Rizal M. Suhardi , Ratna Susandarini , Hilmi Hidayati , Wira Rahardi , Agung Hidayat

Seagrasses are essential marine plants that provide essential services, including nutrient cycling, food, carbon sequestration, and habitats for many organisms. However, they are increasingly threatened by habitat degradation and anthropogenic activity. Unfortunately, data on seagrass diversity and phylogenetics in Seriwe Bay, Lombok Island, is limited. This study aims to assess seagrass diversity and examine evolutionary links through rbcL gene sequences. Seven species of seagrass were identified: Enhalus acoroides, Halophila ovalis, Syringodium isoetifolium, Halodule pinifolia, Halophila spinulosa, Cymodocea rotundata, and Cymodocea serrulata. Phylogenetic analysis identified six clades associated with two families: Hydrocharitaceae (E. acoroides, H. ovalis) and Cymodoceaceae (C. serrulata, C. rotundata, S. isoetifolium, H. pinifolia), with bootstrap values more than 90 % whereas Halophila spinulosa cannot be detected by rbcL. These findings expand our understanding of seagrass biodiversity and are crucial for developing more effective conservation strategies in the region.

海草是重要的海洋植物，提供重要的服务，包括养分循环、食物、碳封存和许多生物的栖息地。然而，它们正日益受到生境退化和人为活动的威胁。不幸的是，关于龙目岛塞里韦湾海草多样性和系统发育的数据有限。本研究旨在通过rbcL基因序列评估海草的多样性并研究其进化联系。共鉴定出7种海草：acoroides、Halophila ovalis、Syringodium isoetifolium、Halodule pinifolia、Halophila spinulosa、Cymodocea rotundata、Cymodocea serrulata。系统发育分析鉴定出水螅科（E. acoroides， H. ovalis）和Cymodoceaceae （C. serrulata， C. rotundata， S. isoetifolium， H. pinifolia）两个科的6个分支，bootstrap值均大于90 %，而盐芽菌（Halophila spinulosa）无法用rbcL检测到。这些发现扩大了我们对海草生物多样性的理解，对于在该地区制定更有效的保护策略至关重要。

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引用次数: 0

GC-biased codon usage and dinucleotide signatures reveal selection on Pi-ta blast resistance gene alleles in Oryza spp. gc偏态密码子使用和二核苷酸特征揭示了稻瘟病抗性基因Pi-ta等位基因的选择。

Q3 Agricultural and Biological Sciences

Ecological Genetics and Genomics

Pub Date : 2026-01-22 DOI: 10.1016/j.egg.2026.100449

Bhaskar Dowarah , Rafiul Amin Laskar , Anurag Kashyap , Bijoy Neog

The rice blast resistance gene Pi-ta is one of the most widely deployed nucleotide-binding leucine-rich repeat (NLR) loci in Oryza breeding programs, yet its synonymous and compositional evolution remains poorly understood. In this study, we analyzed 68 integrity-validated Pi-ta coding sequences (CDS) curated from 256 GenBank records to characterize codon usage bias (CUB) and dinucleotide composition across the genus Oryza. The gene exhibited moderate GC enrichment (49.36 ± 3.57 %), a strong preference for G/C-ending codons, and consistent third-position asymmetries (U > A and G > C). Neutrality analysis revealed a GC12–GC3 regression slope of 0.351, indicating that selective constraints, rather than neutral mutation pressure alone, predominantly shape codon usage at this locus. Dinucleotide profiling further identified universal depletion of TA and GT motifs and enrichment of CA and TG, defining a stable locus-specific compositional signature. Collectively, these results demonstrate that synonymous codon usage in Pi-ta is non-random and evolutionarily constrained, reflecting the combined effects of selection and nucleotide composition. By establishing a genus-wide, locus-specific synonymous profile for Pi-ta, this study provides a novel framework for codon optimization, allele validation, and precision engineering of resistance genes in rice improvement programs.

稻瘟病抗性基因Pi-ta是水稻育种中最广泛使用的核苷酸结合富亮氨酸重复（NLR）位点之一，但其同义性和组成进化尚不清楚。在这项研究中，我们分析了来自256个GenBank记录的68个经过完整性验证的Pi-ta编码序列（CDS），以表征整个水稻属的密码子使用偏差（CUB）和二核苷酸组成。该基因表现出适度的GC富集（49.36 ± 3.57 %），对G/C端密码子的强烈偏好，以及一致的第三位不对称（U >； a和G >； C）。中性分析显示GC12-GC3的回归斜率为0.351，表明选择性约束，而非中性突变压力，主要影响该位点的密码子使用。二核苷酸分析进一步确定了TA和GT基序的普遍缺失和CA和TG的富集，定义了一个稳定的位点特异性组成特征。总之，这些结果表明，同义密码子在Pi-ta中的使用是非随机的和进化约束的，反映了选择和核苷酸组成的综合作用。通过建立一个全属的、特异位点的Pi-ta同义基因图谱，本研究为水稻改良项目中的密码子优化、等位基因验证和抗性基因的精确工程提供了一个新的框架。

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引用次数: 0

Differential response of rice (Oryza sativa L.) genotypes to cold tolerance in western Ethiopia's mid-altitude environments 埃塞俄比亚西部中海拔环境下水稻基因型对耐寒性的差异响应

Q3 Agricultural and Biological Sciences

Ecological Genetics and Genomics

Pub Date : 2026-01-21 DOI: 10.1016/j.egg.2026.100442

Pichiah Gomathinayagam , Usman Mohammed Ali , B.C. Nandeshwar , Samuel Lema , Mehdi Rahimi

Cold stress poses a significant and growing threat to rice production in mid-altitude regions, exacerbated by climate variability. This study assessed the seedling-stage cold tolerance of 35 diverse rice genotypes under natural field conditions in western Ethiopia's mid-altitude zone during the 2019 Meher season. Employing a Randomized Complete Block Design with three replications, seedlings were exposed to natural cold stress, with average nocturnal temperatures of 13 °C and diurnal temperatures averaging 26 °C. Seedling establishment and visual injury, scored using the IRRI Standard Evaluation System (SES), were evaluated at 15 and 30 days after sowing. Analysis of Variance confirmed highly significant (P < 0.01) genotypic differences, and mean separation using Tukey's HSD post-hoc test delineated distinct tolerance groups. Eight genotypes; NERICA 4, Hiber, Abay, Chewaqa, Gambella, Akkavach, Irib, and CO-51 demonstrated remarkable resilience, achieving the highest SES score of 1 (very tolerant) with dark green foliage. Among these, four genotypes (NERICA 4, Hiber, Abay, and Chewaqa) exhibited superior seedling establishment (>73 % survival at 30 DAS) with minimal mortality (3.3–6.9 %) and elevated germination rates (66.6–82.3 %). In contrast, MTU 7029 and RGL 2537 were highly susceptible, suffering 100 % seedling mortality. The strong concordance between quantitative survival data and qualitative SES scores validates the robustness of the screening. The identified cold-tolerant genotypes, particularly the top-performing four, represent valuable genetic resources for direct cultivation or as parental lines in breeding programs aimed at enhancing climate resilience in rice. These findings underscore the importance of local adaptation screening and provide a foundation for developing cold-resilient varieties.

寒冷胁迫对中海拔地区的水稻生产构成了日益严重的威胁，并因气候变化而加剧。本研究评估了埃塞俄比亚西部中高海拔地区35种不同水稻基因型在2019年Meher季节自然大田条件下的苗期耐寒性。采用3个重复的随机完全区组设计，幼苗暴露在自然冷胁迫下，夜间平均温度为13 °C，白天平均温度为26 °C。采用国际水稻研究所（IRRI）标准评价系统（SES）评分，分别在播种后15天和30天对幼苗成活率和视觉损伤进行评分。方差分析证实了高度显著的基因型差异（P <； 0.01），使用Tukey's HSD事后检验的平均分离描述了不同的耐受性组。八个基因型;NERICA 4、Hiber、Abay、Chewaqa、Gambella、Akkavach、Irib和CO-51表现出显著的抗逆性，叶片深绿色，SES得分最高，为1（非常耐）。其中，4个基因型（NERICA 4、Hiber、Abay和Chewaqa）在30 DAS条件下表现出较好的幼苗成活率（>73 %），最低死亡率（3.3-6.9 %）和较高的发芽率（66.6-82.3 %）。而MTU 7029和RGL 2537极易感染，幼苗死亡率高达100% %。定量生存数据和定性SES评分之间的强烈一致性验证了筛选的稳健性。已确定的耐冷基因型，特别是表现最好的4个基因型，代表了直接栽培或在旨在提高水稻气候适应能力的育种计划中作为亲本系的宝贵遗传资源。这些发现强调了本地适应性筛选的重要性，并为开发抗寒品种提供了基础。

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引用次数: 0

eDNA metabarcoding reveals halophilic and halotolerant bacterial assemblages in the salt flats of the northern Red Sea coast eDNA元条形码揭示了红海北部海岸盐滩的嗜盐和耐盐细菌组合

Q3 Agricultural and Biological Sciences

Ecological Genetics and Genomics

Pub Date : 2026-01-21 DOI: 10.1016/j.egg.2026.100448

Jayanath Gopi , Thadickal V. Joydas , Paravanparambil R. Jayachandran , Seerangan Manokaran , Sowmya P. Mohandas , Sajan C. Raju , Syed A. Hussain , Mohamed O. Abouelresh , Sudhanshu Dixit , Muhammed Rafeeq , Mohamed Asharaf , Karuppasamy P. Manikandan , Sharif Hala , Bruno Pulido

The salt flats (sabkhas in Arabic), located in NEOM, Saudi Arabia, along the northern Red Sea coast, are ecologically significant yet vulnerable arid ecosystems that harbor unique microbial biodiversity. These environments are increasingly exposed to varying salinity levels and anthropogenic pressures that may alter microbial community structure. Despite their recognized ecological significance, salt flats remain poorly studied in terms of bacterial diversity using molecular approaches. This study applied environmental DNA (eDNA) metabarcoding of 16 S rRNA gene to assess bacterial community diversity and composition across 30 sabkha soil samples from inland and coastal sites. High-throughput sequencing generated 285,900 high-quality reads, resulting in the identification of 363 operational taxonomic units (OTUs), spanning 219 genera, 49 families, 34 orders, and 8 phyla. The microbial community was dominated by halophilic and halotolerant taxa such as Halomonas, Caldalkalibacillus, Klebsiella, and Vibrio. The most abundant phyla identified were Pseudomonadota and Bacillota. Inland sabkhas contained fewer but highly specialized taxa, whereas coastal sabkhas supported more diverse assemblages, including marine-associated genera. Alpha and beta diversity metrics showed spatial variation, while multivariate analyses indicated soil texture as the key driver of community patterns. These findings represent the first molecular insight into bacterial communities of NEOM sabkhas, providing a baseline for long-term ecological monitoring. The findings support evidence-based conservation and sustainable development efforts and emphasize the utility of eDNA-based monitoring as a tool for guiding ecosystem management in the face of environmental change.

位于沙特阿拉伯NEOM的盐滩（阿拉伯语为sabkhas）沿着红海北部海岸，具有重要的生态意义，但脆弱的干旱生态系统却拥有独特的微生物生物多样性。这些环境越来越暴露于不同的盐度水平和可能改变微生物群落结构的人为压力之下。尽管盐滩具有公认的生态意义，但利用分子方法对其细菌多样性的研究仍然很少。本研究应用环境DNA （environmental DNA, eDNA）元条形码技术对16个 S rRNA基因进行了分析，分析了来自内陆和沿海地区30个sabkha土壤样品的细菌群落多样性和组成。高通量测序产生285,900个高质量reads，鉴定出363个操作分类单位（operational taxonomic units, otu），涵盖49科34目8门219属。微生物群落以嗜盐和耐盐类群为主，如嗜盐单胞菌、Caldalkalibacillus、Klebsiella和Vibrio。发现最多的门是假单胞菌门和杆菌门。内陆sabkhas包含较少但高度专门化的分类群，而沿海sabkhas支持更多样化的组合，包括海洋相关属。α和β多样性指标表现出空间差异，而多变量分析表明土壤质地是群落格局的关键驱动因素。这些发现代表了对NEOM sabkhas细菌群落的首次分子洞察，为长期生态监测提供了基线。这些发现支持了基于证据的保护和可持续发展努力，并强调了基于edna的监测作为面对环境变化指导生态系统管理的工具的效用。

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引用次数: 0

Microbial signatures of maize soils: Shifts in bacterial community across bulk and spermosphere niches 玉米土壤的微生物特征：细菌群落在整体和精子圈生态位上的变化

Q3 Agricultural and Biological Sciences

Ecological Genetics and Genomics

Pub Date : 2026-01-13 DOI: 10.1016/j.egg.2026.100447

Arulanandar Abishagu , Ariyan Manikandan , Pandian Kannan , Narayanan Manikanda Boopathi , A.R.U. Pragadeesh , Murugaiyan Senthilkumar

The spermosphere is a significant constituent of the plant micro-ecosystem, with a distinct role in seed microbial ecology, although it is relatively unexplored. Understanding maize spermosphere microbes is essential for optimizing agricultural practices and enhancing crop productivity. A field study was conducted to investigate the diversity of bacterial communities inhabiting bulk soils and spermosphere soils associated with maize crop using 16S rRNA V3–V4 amplicon sequencing. Overall, 1391 OTUs were identified and classified into 32 phyla, 77 classes, 167 orders, 337 families, 752 genera. Spermosphere shared phylum level features with the bulk soil, such as predominance of Proteobacteria, Firmicutes, Actinobacteria, Planctomycetes, Bacteroidetes, Chloroflexi, Cyanobacteria, Acidobacteria and Nitrospirae. At the genus level, Desulfallas, Chryseolinea, Stenotrophomonas and Niveispirillum shows significantly higher abundances in spermosphere, while Synechococcus, Corynebacterium, and unclassified Clostridiales exhibit notable decreases. Functional prediction revealed 334 KEGG pathways and 6759 orthologs. Spermosphere soils showed higher organic carbon, microbial biomass and respiration than bulk soils, confirming their role as microbial hotspots and potential bioinoculant niches. Ammonia oxidation genes dominated in the spermosphere, whereas nitrate reduction and assimilation genes prevailed in bulk soil. The spermosphere exhibited greater microbial diversity and distinct taxonomic profiles, indicating differences from bulk soil. This preliminary study shows that germinating maize seed had developed a unique microbiome which indicates the importance of considering the spermosphere for developing new bioinoculants based on microbiome studies for sustainable agricultural practices.

精子层是植物微生态系统的重要组成部分，在种子微生物生态中发挥着独特的作用，尽管其研究相对较少。了解玉米精子圈微生物对优化农业实践和提高作物生产力至关重要。采用16S rRNA V3-V4扩增子测序技术，对玉米相关土壤和土壤中细菌群落的多样性进行了研究。共鉴定出1391只otu，隶属于32门77纲167目337科752属。精子圈与土壤具有相同的门水平特征，如变形菌门、厚壁菌门、放线菌门、plantomycetes、拟杆菌门、绿杆菌门、蓝藻门、酸杆菌门、硝化杆菌门等。在属水平上，Desulfallas、Chryseolinea、Stenotrophomonas和Niveispirillum在精子中的丰度显著增加，而Synechococcus、棒状杆菌和未分类的Clostridiales在精子中的丰度显著减少。功能预测显示了334条KEGG通路和6759个同源物。土壤的有机碳含量、微生物生物量和呼吸量均高于普通土壤，证实了其作为微生物热点和潜在的生物接种生态位的作用。土壤中氨氧化基因占主导地位，而硝态氮还原和同化基因占主导地位。土壤中微生物多样性和分类特征明显，与散装土壤存在差异。这项初步研究表明，萌发中的玉米种子已经形成了一个独特的微生物组，这表明在微生物组研究的基础上开发新的生物接种剂对可持续农业实践具有重要意义。

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引用次数: 0

Transcriptomic signatures and soil indicators reveal adaptive stress responses in Quercus oblongata under Pinus invasion in the Western Himalaya 西喜马拉雅地区松入侵下长叶栎的转录组学特征和土壤指标揭示了其适应性胁迫响应

Q3 Agricultural and Biological Sciences

Ecological Genetics and Genomics

Pub Date : 2026-01-12 DOI: 10.1016/j.egg.2026.100445

Md Asif Chowdhary, Hari Shankar Gadri, Sarbani Roy, Vikas Sharma, Pankaj Bhardwaj

Invasion of native oak (Quercus oblongata) forests by Pinus roxburghii is an emerging ecological concern in the Western Himalaya, with implications for biodiversity loss, soil degradation, and altered plant physiological responses. This study integrates transcriptomic analysis and soil chemistry to explore how Pinus invasion affects gene expression and soil conditions in pure and degraded oak forest stands. A total of 13 stress-responsive genes were quantified using transcript abundance data across six forest sites (three pure oak and three mixed Pinus-invaded). Correlation analysis revealed distinct expression patterns: genes such as CAX3, CBL10, and ECH2 showed strong negative associations with key soil parameters (e.g., nitrogen, pH, potassium), indicating upregulation under nutrient-poor, stressed conditions. Conversely, genes like MFL1, CPN20, ACA1, and ALA3 were positively correlated with healthier soil conditions, suggesting their role in supporting plant function in stable environments. Principal component analysis (PCA) further differentiated invaded and pure forests based on both gene expression and edaphic variables. These findings suggest that allelopathic stress and altered soil chemistry in Pinus invaded areas may drive specific molecular adaptations in native species. This approach identifies key genes as potential early biomarkers of forest degradation and offers a molecular insight into plant soil responses under Pinus invasion.

在西喜马拉雅地区，rosburghii松（Pinus roxburghii）入侵本地栎林（Quercus oblongata）是一个新兴的生态问题，可能导致生物多样性丧失、土壤退化和植物生理反应改变。本研究结合转录组学分析和土壤化学分析，探讨了松松入侵对纯栎林和退化栎林基因表达和土壤条件的影响。利用6个森林样地（3个纯栎和3个混松）的转录丰度数据，对13个应激响应基因进行了定量分析。相关分析揭示了不同的表达模式：CAX3、CBL10和ECH2等基因与关键土壤参数（如氮、pH、钾）呈强负相关，表明在营养不良、胁迫条件下表达上调。相反，MFL1、CPN20、ACA1和ALA3等基因与更健康的土壤条件正相关，表明它们在稳定环境中支持植物功能的作用。主成分分析（PCA）基于基因表达和土壤变量进一步区分入侵林和纯林。这些发现表明，化感胁迫和土壤化学的改变可能会驱动本土物种的特定分子适应。该方法确定了关键基因作为森林退化的潜在早期生物标志物，并为松松入侵下植物土壤反应提供了分子视角。

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引用次数: 0

Unveiling the microbial secrets of hydroponically cultivated Humulus lupulus 揭示水培栽培葎草的微生物秘密

Q3 Agricultural and Biological Sciences

Ecological Genetics and Genomics

Pub Date : 2026-01-11 DOI: 10.1016/j.egg.2026.100446

Tripti Singh , Ashwani Mathur

引用次数: 0

Enhancing wheat productivity and increasing the gene expression of TaCAT1 and enzymatic antioxidants under the influence of salicylic acid in desert environments 水杨酸对荒漠环境下小麦产量的影响及对TaCAT1和酶促抗氧化剂基因表达的影响

Q3 Agricultural and Biological Sciences

Ecological Genetics and Genomics

Pub Date : 2026-01-11 DOI: 10.1016/j.egg.2026.100444

Mohammed Ismail Khalaf Al-Fahdawy , Omer Ismail Al-Fahdawi , Amer Hashim Abdulmajeed , Harith Sadaa Madhan AlFahdawy

A field study was implemented in Al-Tharthar, north of Ramadi in Al-Anbar Province, during the 2024–2025 season in a gypsum soil on a farmer's field, to study the impact of salicylic acid on the gene expression of the TaCAT1 gene and the activity of the catalase enzyme and hydrogen peroxide (H₂O₂) accumulation, and the productivity of wheat. The study was implemented using a split-plot system according to the Randomized Complete Block Design. The study showed a pronounced effect of salicylic acid in enhancing TaCAT1 gene expression. The higher concentration of salicylic acid (SA2) doubled the expression values (14.12, 14.02, and 10.43-fold in the three cultivars, respectively). This increase was reflected positively in elevating catalase activity, which helped reduce H₂O₂ accumulation in the plants. Furthermore, salicylic acid improved most yield-related traits. The cultivars varied in their tolerance to desert conditions, with Fatah (G3) outperforming the others in most traits. It recorded averages of spike length (9.17 cm), grains spike⁻¹ (43.00 grains spike⁻¹), grain yield (547.44 kg donum⁻¹), grain protein percentage (8.55 %), and protein yield (48.32 kg donum⁻¹). Other traits were distributed between the Hourani and Sham cultivars. Meanwhile, the SA2 treatment (200 mg L⁻¹) achieved the highest averages across traits: spike length (8.06 cm), grains spike⁻¹ (38.64 spike m⁻²), 500-seed weight (15.22 g), grain yield (500.75 kg donum⁻¹), grain protein percentage (10.61 %), and protein yield (53.46 kg donum⁻¹), Correlation analysis revealed a positive correlation between yield and all traits except for hydrogen peroxide activity, grain density per spike, and 500-grain weight, which showed a negative correlation with grain yield. Pathway analysis demonstrated the direct influence of spike length and number of seeds per spike on yield. As for indirect influences, Caltase enzyme played a significant role in improving most traits, resulting in increased yield.

为了研究水杨酸对小麦TaCAT1基因表达、过氧化氢酶活性和过氧化氢（H2O2）积累以及产量的影响，于2024-2025年在安巴尔省拉马迪北部的Al-Tharthar进行了一项田间研究。本研究采用随机完全区组设计的分割图系统。研究表明，水杨酸对TaCAT1基因表达有明显的增强作用。较高浓度的水杨酸（SA2）使3个品种的表达量分别增加了14.12倍、14.02倍和10.43倍。过氧化氢酶活性的提高有助于降低植物体内H2O2的积累。此外，水杨酸提高了大多数产量相关性状。这些品种对沙漠环境的耐受性各不相同，法塔赫（G3）在大多数性状上优于其他品种。测定了穗长（9.17 cm）、粒穗−1（43.00粒穗−1）、籽粒产量（547.44 kg donum−1）、籽粒蛋白质含量（8.55 %）和蛋白质产量（48.32 kg donum−1）的平均值。其他性状分布在胡拉尼和沙姆品种之间。同时，SA2处理（200 mg L−1）各性状的平均值最高：穗长（8.06 cm）、穗粒数−1（38.64穗粒数m−2）、500粒重（15.22 g）、籽粒产量（500.75 kg donum−1）、籽粒蛋白含量（10.61 %）、籽粒蛋白产量（53.46 kg donum−1）。除过氧化氢活性、穗粒密度、500粒重与籽粒产量呈负相关外，其余性状与产量呈正相关。途径分析表明，穗长和穗粒数对产量有直接影响。间接影响方面，Caltase酶对大部分性状的改善作用显著，提高了产量。

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引用次数: 0

Genetic diversity and phylogenetic relationships among four species of Veneridae (Bivalvia) inferred from molecular data 从分子数据推断四种双壳科植物的遗传多样性和系统发育关系

Q3 Agricultural and Biological Sciences

Ecological Genetics and Genomics

Pub Date : 2026-01-08 DOI: 10.1016/j.egg.2026.100443

Tahani El Ayari , Najoua Trigui El Menif

The genetic diversity and phylogenetic relationships among four species belonging to the family of Veneridae was investigated using the mitochondrial 16S mtDNA. Bivalves have been collected from two stations, Thau lagoon (France) and Radés (Tunisia), situated in the Western Mediterranean basin. The four venerid species were found to have 26 different haplotypes; no haplotype was found to be shared by all the venerid species. Venerupis philippinarum exhibited the highest haplotype and nucleotide diversity (hd = 0.844 and π = 0.120). The genetic differentiation between the venerids species was proved with the high percentage of variation 53.87 % and high genetic distances. Furthermore, the genetic distances between V. decussata populations were low. The samples collected in the Mediterranean Thau lagoon, France provide morphological evidence of the probable occurrence of hybridization between native V. decussata and introduced V. philippinarum. This result was confirmed using nuclear markers (ITS1, ITS2 and 5S rDNA).

利用线粒体16S mtDNA分析了金星科4个物种的遗传多样性和系统发育关系。从位于西地中海盆地的Thau泻湖（法国）和rad（突尼斯）两个站点收集了双壳类动物。发现4种毒蛇有26种不同的单倍型；没有发现所有毒蛇属物种共有的单倍型。菲律宾Venerupis philippinarum单倍型和核苷酸多样性最高（hd = 0.844,π = 0.120）。菊科植物间存在遗传分化，变异率高达53.87 %，遗传距离高。此外，居群间遗传距离较低。在法国地中海Thau泻湖采集的样本提供了本地V. decussata与引进V. philippinarum杂交可能发生的形态学证据。核标记（ITS1、ITS2和5S rDNA）证实了这一结果。

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