Search Results (257)

Lonicera japonica Thunb. is a traditional Chinese medicinal herb whose floral buds are the primary source of pharmacological compounds that require manual harvesting. As a result, its floral bud duration, determined by the opening time, is a key determinant of both quality and economic value. However, the genetic mechanisms controlling floral bud duration remain poorly understood. In this study, we employed population structure analysis and molecular experiments to identify candidate genes associated with this trait. The improved cultivar Beihua No. 1 (BH1) opens its floral buds significantly later than the landrace Damaohua (DMH). Exogenous application of methyl jasmonate (MeJA) to BH1 indicated that jasmonate acts as a negative regulator of floral bud duration by accelerating floral bud opening. A genome-wide selection scan across 35 germplasms with varying floral bud durations identified the transcription factor LjWRKY50 as the causative gene influencing this trait. The dual-luciferase reporter assay and qRT-PCR experiments showed that LjWRKY50 activates the expression of the jasmonate biosynthesis gene, LjAOS. A functional variant within LjWRKY50 (Chr7:24636061) was further developed into a derived cleaved amplified polymorphic sequence (dCAPS) marker. These findings provide valuable insights into the jasmonate-mediated regulation of floral bud duration, offering genetic and marker resources for molecular breeding in L. japonica. Full article

Tetranychus urticae, commonly known as the two-spotted spider mite, is a highly adaptable and polyphagous arthropod in the family Tetranychidae, capable of feeding on over 1200 plant species, including strawberries (Fragaria × ananassa Duch.). The fitness and microbiota of herbivorous arthropods can vary significantly across different plant species and cultivars. In this study, we investigated the fecundity, longevity, growth rate, and microbiota composition of T. urticae reared on seven Chinese strawberry cultivars: Hongyan (HY), Yuexiu (YX), Tianshi (TS), Ningyu (NY), Xuetu (XT), Zhangjj (ZJ), and Xuelixiang (XLX). Our findings revealed significant differences among cultivars: mites reared on the XT cultivar exhibited the highest fecundity (166.56 ± 7.82 eggs), while those on XLX had the shortest pre-adult period (7.71 ± 0.13 days). Longevity was significantly extended in mites reared on XLX, XT, and NY cultivars (25.95–26.83 days). Microbiota analysis via 16S rRNA sequencing showed that Proteobacteria dominated (>89.96% abundance) across all mite groups, with Wolbachia as the predominant symbiont (89.58–99.19%). Male mites exhibited higher bacterial diversity (Shannon and Chao1 indices) than females, though Wolbachia abundance did not differ significantly between sexes or cultivars. Functional predictions highlighted roles of microbiota in biosynthesis, detoxification, and energy metabolism. These findings underscore the influence of host plant variety on T. urticae fitness and microbiota composition, suggesting potential strategies for breeding resistant strawberry cultivars and leveraging microbial interactions for pest management. Full article

Aphelenchoides besseyi is considered a highly prevalent facultative plant-parasitic nematode and has a significant impact on various economically important crops globally. Due to the lack of knowledge on the efficacy of various management techniques, A. besseyi is still challenging to control in the open field. The present investigation successfully shed light on some significant new points, including the following: (1) A. besseyi was confirmed inside all soybean tissues—including roots, stems, leaves, and seeds—indicating its endoparasitic nature and its strong ability to reach the upper foliar system where it causes green stem and foliar retention syndrome (GSFR) symptoms; (2) inoculated plants exhibited reduced vegetative growth parameters, as non-inoculated control soybean plants showed higher values of plant height (PH), fresh root weight (FRW), and fresh shoot weight (FSW) compared to inoculated plants; (3) Yudou 29 was identified as highly resistant to A. besseyi, as results from the resistance screening assay among different Chinese soybean cultivars confirmed its strong resistance under natural field infestation conditions; and (4) soybean seeds may act as inoculum sources of A. besseyi, highlighting the need to develop more effective control measures to prevent or limit nematode dissemination through seed transmission. Full article

Wheat leaf rust (Lr), caused by Puccinia triticina Eriks. (Pt), is one of the most important diseases affecting wheat production worldwide. Using resistant wheat cultivars is the most economic and environmentally friendly way to control leaf rust. The Chinese wheat cultivar Xinong1163-4 has shown good resistance to Lr in field trials. To identify the genetic basis of Lr resistance in Xinong1163-4, 195 recombinant inbred lines (RILs) from the Xinong1163-4/Thatcher cross were phenotyped for Lr severity in three environments: the 2017/2018, 2018/2019, and 2019/2020 growing seasons in Baoding, Hebei Province. Bulked segregant analysis and simple sequence repeat markers were then used to identify the quantitative trait loci (QTLs) for Lr adult plant resistance (APR) in the population. As a result, six QTLs were detected, designated as QLr.hbau-1BL.1, QLr.hbau-1BL.2, and QLr.hbau-1BL.3. These QTLs were predicted to be novel. QLr.hbau-4BL, QLr.hbau-4BL.1, and QLr.hbau-3A were identified at similar physical positions to previously reported QTLs. Based on chromosome positions and molecular marker testing, QLr.hbau-1BL.3 shares similar flanking markers with Lr46. Lr46 is a non-race-specific APR gene for leaf rust, stripe rust, and powdery mildew. Similarly, QLr.hebau-4BL showed resistance to multiple diseases, including leaf rust, stripe rust, Fusarium head blight, and powdery mildew. The QTLs identified in this study, as well as their closely linked markers, can potentially be used for marker-assisted selection in wheat breeding. Full article

Hydroponics is currently one of the primary methods for soilless cultivation. Although the phenotype and quality of vegetables differ between hydroponic and soil-based systems, limited research has been conducted on the selection and breeding of pakchoi cultivars specifically suited for hydroponics. In this study, principal component analysis (PCA) and cluster analysis were performed on the commercial traits, agronomic characteristics, and nutritional quality of 20 pakchoi parental lines grown under hydroponic conditions to classify and screen suitable germplasm for breeding. PCA reduced the 11 agronomic traits into two independent principal components, accounting for a cumulative contribution of 79.22%. Cluster analysis grouped the 20 parental lines into four categories based on the composite scores of agronomic traits and nutritional quality. Group 3 was selected for breeding programs aiming to develop high-yielding cultivars with a desirable morphology. For breeding targets emphasizing darker leaves and petiole coloration, Group 4 presented the most suitable germplasm. Group 1 was ideal for enhancing nutritional quality by offering parent lines rich in calcium, magnesium, vitamin C, and amino acids. Alternatively, Group 2 contained lines with high levels of soluble proteins, amino acids, and soluble sugars. Full article

Wheat stripe rust (Puccinia striiformis f. sp. tritici, Pst) resistance and agronomic traits are crucial determinants of wheat yield. Elucidating the quantitative trait loci (QTLs) associated with these essential traits can furnish valuable genetic resources for improving both the yield potential and disease resistance in wheat. Lantian 31 is an excellent Chinese winter wheat cultivar; multi-environment phenotyping across three ecological regions (2022–2024) confirmed stable adult-plant resistance (IT 1–2; DS < 30%) against predominant Chinese Pst races (CYR31–CYR34), alongside superior thousand-kernel weight (TKW) and kernel morphology. Here, we dissected the genetic architecture of these traits using a total of 234 recombinant inbred lines (RILs) derived from a cross between Lantian 31 and the susceptible cultivar Avocet S (AvS). Genotyping with a 15K SNP array, complemented by 660K SNP-derived KASP and SSR markers, identified four stable QTLs for stripe rust resistance (QYrlt.swust-1B, -1D, -2D, -6B) and eight QTLs governing plant height (PH), spike length (SL), and kernel traits. Notably, QYrlt.swust-1B (1BL; 29.9% phenotypic variance) likely represents the pleiotropic Yr29/Lr46 locus, while QYrlt.swust-1D (1DL; 22.9% variance) is the first reported APR locus on chromosome 1DL. A pleiotropic cluster on 1B (670.4–689.9 Mb) concurrently enhanced the TKW and the kernel width and area, demonstrating Lantian 31’s dual utility as a resistance and yield donor. The integrated genotyping pipeline—combining 15K SNP discovery, 660K SNP fine-mapping, and KASP validation—precisely delimited QYrlt.swust-1B to a 1.5 Mb interval, offering a cost-effective model for QTL resolution in common wheat. This work provides breeder-friendly markers and a genetic roadmap for pyramiding durable resistance and yield traits in wheat breeding programs. Full article

The SHORT INTERNODES-related sequence (SRS) gene family, comprising zinc finger and IXGH domain-containing transcription factors, serves as a critical regulator of plant biological processes and abiotic stress responses. In this study, the common wheat cultivar Chinese Spring was selected as the experimental material. Comprehensive bioinformatic analysis was performed using ClustalX, MEGA, MEME, and PlantTFDB v5.0 to systematically characterize SRS family members within the wheat genome. The systematic examination of physicochemical properties, conserved domains, phylogenetic relationships, gene structures, and cis-acting elements was conducted, providing insights into the functional roles of this gene family in wheat growth and development. Fifteen SRS family members containing conserved zinc finger and IXGH domains were identified. Distinct expression patterns were observed among TaSRS subgroups: Members of Groups I, III, and V exhibited significantly higher transcript levels in roots, stems, leaves, and anthers compared to other subgroups. Notably, the majority of TaSRS genes, including representatives from Groups I, III, IV, and V, displayed responsiveness to NaCl and ABA stress treatments, suggesting their putative involvement in both salinity adaptation and phytohormone-mediated stress signaling. Differential expression patterns of TaSRS genes under NaCl and ABA stress were identified, revealing distinct regulatory impacts of these stressors on transcription. These findings establish a framework for investigating the molecular mechanisms underlying stress adaptation in wheat physiology. Full article

An exploration and understanding of cultivar adaptability to specific environmental conditions are critical in rice breeding. This study aimed to compare the agro-morphological data of 36 japonica rice cultivars (Oryza sativa L.) from Chinese rice accessions grown under two different environments (Fengyang and Hexian) and to identify important genes associated with key traits in the cultivars. Higher significant differences were observed between Fengyang and Hexian in traits like, grain width, grain length, yield per plot, plant height, and tiller number with cultivars grown in Hexian having the greatest values. This revealed that the environment in Hexian favored these traits, and most cultivars performed better in Hexian than in Fengyang. Correlation analysis also showed strong positive correlations between tiller number and yield per plot in both environments, indicating the influence of tiller number on rice yield potential. The PCR analysis showed the amplification of DEP1, Ghd7, Wx, Chalk5, COLD1, DST, Xa13, and Bph6 in most japonica cultivars, indicating presence of these genes in the cultivars. This study suggests that differences in agronomic performance between the cultivars grown in Fengyang and Hexian might be caused by differences in environmental conditions. This finding could be valuable for future breeding of high-yielding and climate-resilient cultivars. Full article

While the effects of elevated CO₂ (eCO₂) on crops have been extensively studied, cultivar-specific responses and impacts under higher CO₂ concentrations (>800 μmol/mol) remain unclear. Here, we addressed these two aspects to reveal the effects of eCO₂ (approximately 900 μmol/mol) on the yield and quality of three wheat cultivars, Chinese spring (CS), Chuanmai 44 and Neimai 9. The results indicated the net photosynthetic rate (Pn) and water use efficiency (WUEi) of the three cultivars significantly increased under 900 μmol/mol CO₂ concentration. Elevated CO₂ increased the hundred-grain weight (HGW) of Chuanmai 44 (+32.51%, p < 0.05) and Neimai 9 (+8.47% p < 0.05), but had little effect on HGW of CS. CO₂ elevation significantly increased the N content in the grain of CS (+7.27%, p < 0.05). Elevated CO₂ enhanced amino acid biosynthesis in CS but suppressed it in Chuanmai 44 and Neimai 9. No significant changes in grain mineral concentrations occurred in CS and Chuanmai 44 under eCO₂ conditions. Neimai 9 demonstrated significant decreases in K and Mg, with non-significant reductions in other elements. The effects of eCO₂ on grain yield and quality were closely linked to cultivars. This study will provide insights for understanding effects of CO₂ concentration and cultivar interactions on crop growth and selecting wheat cultivar to cope with future climate change. Full article

Leaf rust (LR) is a devastating foliar disease that impacts common wheat (Triticum aestivum L.) globally. For optimal disease protection, wheat cultivars should possess adult plant resistance (APR) to leaf rust. In the current study, the objective was to map quantitative trait loci (QTL) related to leaf rust resistance. This was achieved by using 193 recombinant inbred line (RIL) populations which were developed from the cross between N. Strampelli and Huixianhong. Four trials were conducted in China (three in Baoding, Hebei province, and one in Zhoukou, Henan province) to assesses the leaf rust response of the RILs and parental lines. The wheat 660K SNP array and additional SSR markers were used to genotype the RIL populations. Through inclusive composite interval mapping (ICIM), three QTL related to leaf rust (LR) resistance were detected. ICIM was also employed to reevaluate previously published data in order to identify QTL with pleiotropic effects. To determine the physical positions, the flanking sequences of all SNP probes were compared against the Chinese Spring wheat reference sequence through BLAST searches. Three leaf rust resistance loci, two on chromosome 2A and 5B, were contributed by N. Strampelli. QLr.hbau-2AL.1 was detected in three leaf rust environments with phenotypic variance explained (PVE of 12.2–17%); QLr.hbau-2AL.2 was detected in two environments with 12.5–13.2% of the PVE; and QLr.hbau-5BL was detected in all leaf rust environments with phenotypic variance explained (PVE) of 17.8–19.1%. QLr.hbau-5BL exhibited potentially pleiotropic responses to multiple diseases. The QTL and the associated flanking markers discovered in this study could prove valuable for purposes such as fine mapping, the exploration of candidate genes, and marker-assisted selection (MAS). Full article

Cadmium (Cd) pollution in paddy soils causes a great threat to safe rice production in China. In this review, we summarized the key advances in the research of Cd pollution sources and statuses in Chinese soil and rice, explore the mechanisms of Cd transformation in the rice–soil system, discuss the agronomic strategies for minimizing Cd accumulation in rice grains, and highlight advancements in developing rice cultivars with low Cd accumulation. Anthropogenic activity is a main source of Cd in farmland. Cd in soil solutions primarily enters rice roots through a symplastic pathway facilitated by transporters like OsNRAMP5, OsIRT1, and OsCd1, among which OsNRAMP5 is identified as the primary contributor. Subsequently, Cd translocation is from roots to grains through the xylem and phloem, regulated by transporters such as OsHMA2, OsLCT1, and OsZIP7. Meanwhile, Cd sequestration in vacuoles controlled by OsHMA3 plays a crucial role in regulating Cd mobility during its translocation. Cd accumulation in rice was limited by the available Cd concentration in soil solutions, Cd uptake, and translocation in rice plants. Conventional agronomic methods aimed at reducing grain Cd in rice by suppressing Cd bio-availability without decreasing soil Cd content have been proven limited in the remediation of Cd-polluted soil. In recent years, based on the mechanisms of Cd absorption and translocation in rice, researchers have screened and developed low-Cd-accumulation rice varieties using molecular breeding techniques. Among them, some new cultivars derived from the null mutants of OsNRAMP5 have demonstrated a more than 93% decrease in grain Cd accumulation and can be used for applications in the next years. Therefore, the issue of Cd contamination in the rice of China may be fully resolved within a few years. Full article

Wheat stem rust, caused by Puccinia graminis f. sp. tritici, is a major disease that severely affects safe wheat production. The Huanghuai region plays a vital role in China’s wheat production and the wheat stem rust epidemic across China. However, due to China’s effective control measures, wheat stem rust rarely occurs in the region, resulting in little research on this disease, including the determination of resistance genes in cultivars and elite lines. For this purpose, this study utilized two predominant races (21C3CTHQM and 34MKGQM) of P. graminis f. sp. tritici to determine the resistance levels of 64 wheat cultivars in the Huanghuai wheat region. Additionally, molecular markers linked with Sr24, Sr25, Sr26, Sr31, and Sr38 were used to analyze the presence of these genes. The results indicated that among the 62 wheat cultivars and elite lines, 13 cultivars contained Sr31, four cultivars were detected to contain Sr38, and none contained Sr24, Sr25, or Sr26. Field tests in 2023 showed that three (4.8%) cultivars exhibited immunity to both races, while 20 (32.3%) and 23 (37.1%) cultivars showed resistance to moderate resistance, and 39 (62.9%) and 36 (58.1%) cultivars were moderately susceptible to susceptible. In 2024, one (1.6%) and four (6.5%) cultivars demonstrated immunity to both races, 22 (35.5%) and 23 (37.1%) cultivars showed resistance to moderate resistance, and 39 (62.9%) and 35 (56.5%) cultivars were moderately susceptible to susceptible. With over 50% of the cultivars displaying susceptibility, the overall resistance level was relatively low, indicating that stem rust outbreaks could recur if a sufficient inoculum is present. It is crucial to explore new resistance sources, discover novel resistance genes, and breed wheat cultivars with durable resistance and desirable agronomic traits to enhance the overall resistance to stem rust in Chinese wheat-growing regions. Full article

Dehydrins (DHNs) belong to the second family of late embryogenesis abundant (LEA) proteins, which are widely distributed in plants. We cloned a SK₃-type DHN gene named WZY1-2 in Zheng yin 1 cultivar of Triticum aestivum. An ERF-type transcription factor TaERF4a was found to be involved in the regulation of the dehydrin WZY1-2 gene in our last report. The stress-responsive ability and dual-luciferase assay demonstrated that TaERF4a positively regulates WZY1-2 gene transcription under stress conditions. In this study, we further characterized the role of the transcription factor TaERF4a in plant drought tolerance. Arabidopsis thaliana heterologously overexpressing TaERF4a exhibited higher survival rate, increased superoxide dismutase (SOD) activity, elevated proline and chlorophyll content, and reduced malondialdehyde (MDA) content under drought conditions. Conversely, silencing TaERF4a in Chinese spring wheat using the virus-induced gene silencing (VIGS) method increased the sensitivity of plants to drought stress. Furthermore, we identified the specific binding site of TaERF4a in the WZY1-2 promoter. Electrophoretic mobility shift assay (EMSA) and dual-luciferase reporter assay demonstrated that TaERF4a activates the expression of the WZY1-2 dehydrin gene through binding to the DRE cis-element in its promoter. Taken together, the results of our study indicate that TaERF4a positively regulates the expression of the dehydrin WZY1-2 gene and enhances drought tolerance in plants. Full article

Leaves are the primary organs for plant photosynthesis, and their flat, symmetric morphology is crucial for plant growth and development. The LBD family transcription factor ASYMMETRIC LEAVES 2 (AS2) plays a central role in the establishment of leaf polarity. In this study, we cloned the BcAS2 gene from the non-heading Chinese cabbage cultivar “NHCC001” and successfully generated overexpression strains through genetic transformation. Phenotypic analysis revealed that overexpression of BcAS2 led to significant upward curling of leaves in non-heading Chinese cabbage. Additionally, we found that the expression of BcPHB, a gene associated with leaf adaxial polarity development, was significantly up-regulated in BcAS2-overexpressing plants compared to controls. This interaction was further confirmed through yeast one-hybridization (Y1H), dual-luciferase reporter assays, and electrophoretic mobility shift assay (EMSA), all of which demonstrated that BcAS2 directly binds to the GATA-motif site of the BcPHB promoter and promotes its transcription. Functional validation via overexpression and silencing of BcPHB confirmed its role in regulating adaxial polarity development in non-heading Chinese cabbage leaves. This study elucidates the molecular mechanism of the BcAS2-BcPHB pathway in regulating leaf polarity in non-heading Chinese cabbage, providing a theoretical foundation for morphological improvement breeding. Full article

Soybean, an economically valuable oil and protein crop, is vulnerable to numerous biotic stresses throughout its growth period. Soybean mosaic virus (SMV), a destructive plant pathogen, induces substantial yield reduction and seed quality deterioration globally. In China, a total of 22 distinct SMV strains have been documented, with SMV-SC4 being a widely spread strain. The Chinese cultivar Kefeng-1 (KF) is resistant to this strain. To investigate the resistance mechanism, transcriptional analysis was performed at 0, 6, 24, and 48 h post-inoculation of SC4 in KF (Resistant) and NN1138-2 (NN) (Susceptible). A total of 1201 core differentially expressed genes (DEGs) were identified as active ones against SC4 infection, with most originating from the resistant cultivar at the early infection stages. Gene ontology enrichment analysis indicated that the DEGs directly involved in signal transduction and those related to plant stress response contributed to KF resistance indirectly, including protein phosphorylation, protein kinase activity, oxidation–reduction, oxidoreductase activity, catalytic activity, metal ion transport, and response to auxin. A total of 27 genes in “Signal transduction” with most of them were disease resistance conserved domains, 52 genes active in oxidoreductase activity involving in removing ROS from SMV attack, and 8 genes in “Response to auxin”, a phytohormone that plays a role in biotic stress response in addition to growth and development. These genes expressed more differentially in the resistant versus susceptible cultivar. Our findings provide insights into the molecular networks related to soybean response to SMV, which may be relevant in understanding soybean resistance against the viral infections. Full article