Wheat (Triticum aestivum L.) serves as a critically important staple crop worldwide, and mutation breeding through Cobalt-60 (60Co-γ) radiation has been widely adopted as an effective strategy for genetic improvement. In this study, ten wheat cultivars from Shandong, Henan, and Hebei were subjected to 60Co-γ irradiation to develop an M2 mutant population comprising 10,350,000 lines. Systematic screening M2 mutant population under natural conditions identified 158 freezing-tolerant mutants, 441 saline-alkali-tolerant mutants, and >5,000 mutants with changed yield or quality traits. This population represents a valuable genetic resource for collaborative research and provides a powerful platform for functional genomics studies and breeding applications.
The sustainable production of Dioscorea polystachya (Chinese yam) is severely compromised by a vicious cycle of excessive chemical dependency and complex biotic stresses including anthracnose, nematodes, thrips and other associated pests and diseases. Moreover, the efficacy of single biocontrol agents in field applications often proves unstable, and balancing the growth–defense trade-off remains challenging. To break these impasses, we established a novel “ZR Integrated Green Control System” (ZR-IGCS) by coupling an active plant immune inducer ZNC with a functional microbial agent Recharge. This system establishes a dual defense barrier, orchestrating internal immune activation with external micro-ecological regulation to engineer ecological synergy. Field trials demonstrated that the ZR-IGCS significantly accelerated seed tuber germination and seedling biomass accumulation. It established a spatiotemporal complementary defense network, exhibiting excellent integrated pest and disease control efficacy. The system maintained over 60% efficacy against foliar diseases such as anthracnose and brown spot, while enhancing the control of soil-borne diseases like wilt and root-lesion nematodes by more than 60% and 30%, respectively. It also achieved ~48% specific control of thrips. Crucially, ZR-IGCS alleviated the growth–defense conflict, significantly delaying plant senescence and synchronously optimizing yield structure for aerial beans and underground tubers. This synergy increased the proportion of high-quality yam beans, yielded a 51.66% surge in high-quality tubers, and improved total economic benefits by ~30%. The combined system successfully bridges the gap between laboratory potential and field stability for yam production, offering a robust and sustainable strategy to mitigate continuous cropping obstacles and reduce chemical inputs.
Wheat (Triticum aestivum) supplies approximately 20% of the protein and calories of the human diet (Apples et al. 2018).Wheat yield and quality are influenced by numerous factors,including weeds. Competition between wheat and weeds occurs throughout the wheat life cycle,affecting wheat growth and productivity. Managing weedy grasses has long been a challenge in wheat fields,particularly in seed production fields.
All terrestrial plants possess a hydrophobic cuticle in the outermost layer of their aerial organs that is composed of cutin and wax. The cuticle serves as the first barrier between the plant and the surrounding environment and plays a key role in the resistance of plants to abiotic and biotic stressors. Additionally, they are closely associated with plant growth and development. Cuticular wax has attracted considerable attention as the main mediator of cuticular functions. In this review, we summarize the advances in the research investigating wheat cuticular wax, focusing on three aspects that include biosynthesis, genetics, and stress responses. Additionally, we discuss the applications of cuticular wax in wheat breeding.
Wheat germplasm is a fundamental resource for basic research, applied studies, and wheat breeding, which can be enriched normally by several paths, such as collecting natural lines, accumulating breeding lines, and introducing mutagenesis materials. Ethyl methane sulfonate (EMS) is an alkylating agent that can effectively introduce genetic variations in a wide variety of plant species. In this study, we created a million-scale EMS population (MEP) that started with the Chinese wheat cultivars 'Luyan 128', 'Jimai 38', 'Jimai 44', and 'Shannong 30'. In the M1 generation, the MEP had numerous phenotypical variations, such as >3,000 chlorophyll-deficient mutants, 2,519 compact spikes, and 1,692 male sterile spikes. There were also rare mutations, including 30 independent tillers each with double heads. Some M1 variations of chlorophyll-deficiency and compact spikes were inheritable, appearing in the M2 or M3 generations. To advance the entire MEP to higher generations, we adopted a single-seed descendent (SSD) approach. All other seed composites of M2 were used to screen other agronomically important traits, such as the tolerance to herbicide quizalofop-P-methyl. The MEP is available for collaborative projects, and provides a valuable toolbox for wheat genetics and breeding for sustainable agriculture.
Premature senescence is an important factor affecting wheat yield and quality. Wheat yield can be increased by delaying senescence and prolonging the effective photosynthetic time. Previously, we found that the cis-zeatin-O-glucosyltransferase (cZOGT1) gene plays an important role in the stay-green wheat phenotype. In this study, cZOGT1-overexpressing lines exhibited a delayed senescence phenotype, despite a significant reduction in the total cytokinin content. Further, we found that cZOGT1 interacted with the Ca2+-dependent lipid binding protein TaZIP (cZOGT1-interacting protein), and that a high level of cZOGT1 expression led to the suppression of TaZIP expression, which in turn, reduced abscisic acid (ABA) content. The synergistic reduction in cytokinins and ABA levels eventually caused the stay-green phenotype in cZOGT1-overexpressing lines. This study provides a new theoretical basis to explain the mechanism underlying the wheat stay-green phenotype and provides a genetic resource for wheat molecular-design breeding.
Premature senescence is an important factor affecting wheat yield and quality. Wheat yield can be increased by delaying senescence and prolonging the effective photosynthetic time. Previously, we found that the cis-Zeatin-O-glucosyltransferase (cZOGT1) gene plays an important role in the stay-green wheat phenotype. In this study, cZOGT1-overexpressing lines exhibited a delayed senescence phenotype, despite a significant reduction in the total cytokinin content. Further, we found that cZOGT1 interacted with TaZIP, and that a high level of cZOGT1 expression led to the suppression of TaZIP expression, which in turn, reduced abscisic acid (ABA) content. The synergistic reduction in cytokinins and ABA levels eventually caused the stay-green phenotype in cZOGT1-OE lines. This study provides a new theoretical basis to explain the mechanism underlying the wheat stay-green phenotype and provides an excellent genetic resource for wheat molecular-design breeding.
This study investigated the barley lesion mimic mutant (LMM) 5386, evidenced by a leaf brown spot phenotype localized on the chromosome 3H, and its conferred basal resistance to Fusarium graminearum. RNA-seq analysis identified 1453 genes that were differentially expressed in LMM 5386 compared to those in the wild type. GO and KEGG functional annotations suggested that lesion mimic formation was mediated by pathways involving oxidation reduction and glutathione metabolism. Additionally, reactive oxygen species (ROS) accumulation in brown spots was substantially higher in LMM 5386 than in the wild-type plant; therefore, antioxidant competence, which is indicated by ROS accumulation, was significantly lower in LMM 5386. Furthermore, the reduction of glycine in LMM 5386 inhibited glutathione biosynthesis. These results suggest that the decrease in antioxidant competence and glutathione biosynthesis caused considerable ROS accumulation, leading to programmed cell death, which eventually reduced the yield components in LMM 5386.
Abstract This study investigated barley lesion mimic mutant (LMM) 5386, it exhibited a leaf brown spot phenotype and conferred basal resistance to F. graminearum. RNA-seq analysis identified 1453 differentially expressed genes in LMM 5368 compared to those in the wild type. GO and KEGG functional annotations suggested that lesion mimic formation was mediated by pathways involving oxidation-reduction and glutathione metabolism. In addition, the accumulation of reactive oxygen species (ROS) in brown spots was substantially higher in LMM 5368. Antioxidant competence, as indicated by ROS accumulation, was significantly lower in LMM 5368. Further, the reduction of glycine in LMM 5386 inhibited glutathione biosynthesis. These results suggest that the decrease in antioxidant competence and glutathione caused the accumulation of large amounts of ROS and thus led to programmed cell death in leaves of LMM 5386, which eventually reduced the yield components in LMM 5386.
Tomato (Solanum lycopersicum) is a highly valuable fruit crop, and yield is one of the most important agronomic traits. However, the genetic architecture underlying tomato yield-related traits has not been fully addressed. Based on ∼4.4 million single nucleotide polymorphisms obtained from 605 diverse accessions, we performed a comprehensive genome-wide association study for 27 agronomic traits in tomato. A total of 239 significant associations corresponding to 129 loci, harboring many previously reported and additional genes related to vegetative and reproductive development, were identified, and these loci explained an average of ∼8.8% of the phenotypic variance. A total of 51 loci associated with 25 traits have been under selection during tomato domestication and improvement. Furthermore, a candidate gene, Sl-ACTIVATED MALATE TRANSPORTER15, that encodes an aluminum-activated malate transporter was functionally characterized and shown to act as a pivotal regulator of leaf stomata formation, thereby affecting photosynthesis and drought resistance. This study provides valuable information for tomato genetic research and breeding.
Isochorismate synthase (ICS) is a key enzyme for the synthesis of salicylic acid (SA) in plants. SA mediates plant responses to both biotic and abiotic stresses. In previous studies, we found that overexpression of ICS (ICSOE) or suppression of ICS (ICSRNAi) affected the host response to Fusarium graminearum in barley. However, whether the barley ICS gene plays a role in adapting to abiotic stresses remains to be determined. In the present study, expression of the ICS gene was upregulated when treated with 20 % PEG6000, and ICSOE lines were more drought tolerant than wild type (WT) and ICSRNAi. In addition, the abscisic acid (ABA) levels in the ICSOE lines were higher than those in the WT and ICSRNAi lines under drought stress. High ABA levels significantly reduced Gs and E, which may impact water retention under drought stress. Under drought conditions, the activity of antioxidant enzymes was significantly higher in the ICSOE lines, correlating with a lower levels of reactive oxygen species (ROS) and malondialdehyde (MDA). Enhanced antioxidant competence also contributed to drought tolerance in ICSOE lines. These findings help elucidate the abiotic stress resistance of the ICS pathway in barley.
植物科学与技术专业为农业高校传统专业.近几年,随着枣庄学院向应用型大学转型发展的要求,对植物科学与技术专业建设提出了新的要求,专业加强实践教学,培养富有创新精神和开拓能力,适于区域农业发展的应用型高级技术人才.文章旨在探讨植物科学与技术专业的建设,以适应鲁南地区经济发展的需要.
Drought and rising global temperatures are important factors that reduce wheat production. Trehalose protects the reaction centres and improves photosystem II (PSII) activity under diverse stress conditions. However, the underlying mechanism remains unknown. Cyclic electron flow (CEF) plays an important role in protecting PSII under environmental stresses. Our study focused on the effects of exogenous trehalose on the activity of PSII, D1 protein content, plastoquinone (PQ) pool and ATP synthase activity in wheat seedlings under heat and drought stresses to explore the relationship between trehalose and CEF. The results indicated that heat and drought stresses decreased maximum photochemical efficiency of PSII (Fv /Fm ) and electron transport rate of PSII (EFR(II)), whereas the trehalose pretreatment improved photochemical efficiency and electron transport rate of PSII. The trehalose pretreatment stimulated CEF under heat and drought stresses. Furthermore, the proton gradient (ΔpH) across the thylakoid membrane and ATPase activity increased. The higher ΔpH and ATPase activity played a key role in protecting PSII under stresses. Trehalose pretreatment could reduce inhibition caused by heat and drought stresses on the PQ pool. Thus, our results indicated that photoinhibition in heat- and drought-stressed plants was alleviated by the trehalose pretreatment, which was mediated by CEF and the PQ pool.
Expansins loosen plant cell walls and are involved in cell enlargement and various abiotic stresses. In previous studies, we cloned the expansin gene TaEXPA2 from the wheat cultivar HF9703. Here, we studied its function and regulation in wheat drought stress tolerance. The results indicated that TaEXPA2-overexpressing wheat plants (OE) exhibited drought tolerant phenotypes, whereas down-regulation of TaEXPA2 by RNA interference (RNAi) resulted in elevated drought sensitivity, as measured by survival rate, photosynthetic rate and water containing ability under drought stress. Overexpression of TaEXPA2 enhanced the antioxidant capacity in wheat plants, via elevation of antioxidant enzyme activity and the increase of the transcripts of some ROS scavenging enzyme-related genes. Further investigation revealed that TaEXPA2 positively influenced lateral root formation under drought conditions. A MYB transcription factor of wheat named TaMPS activates TaEXPA2 expression directly by binding to its promoter. Overexpression of TaMPS in Arabidopsis conferred drought tolerance associated with improved lateral root number, and the close homolog genes of TaEXPA2 were up-regulated in Arabidopsis roots overexpressing TaMPS, which suggest that TaMPS may function as one of the regulator of TaEXPA2 gene expression in the root lateral development under drought stress. These findings suggest that TaEXPA2 positively regulates drought stress tolerance in wheat.
U-box E3 ubiquitin ligases play important roles in the ubiquitin/26S proteasome machinery and in abiotic stress responses. TaPUB1-overexpressing wheat (Triticum aestivum L.) were generated to evaluate its function in salt tolerance. These plants had more salt stress tolerance during seedling and flowering stages, whereas the TaPUB1-RNA interference (RNAi)-mediated knock-down transgenic wheat showed more salt stress sensitivity than the wild type (WT). TaPUB1 overexpression upregulated the expression of genes related to ion channels and increased the net root Na+ efflux, but decreased the net K+ efflux and H+ influx, thereby maintaining a low cytosolic Na+ /K+ ratio, compared with the WT. However, RNAi-mediated knock-down plants showed the opposite response to salt stress. TaPUB1 could induce the expression of some genes that improved the antioxidant capacity of plants under salt stress. TaPUB1 also interacted with TaMP (Triticum aestivum α-mannosidase protein), a regulator playing an important role in salt response in yeast and in plants. Thus, low cytosolic Na+ /K+ ratios and better antioxidant enzyme activities could be maintained in wheat with overexpression of TaPUB1 under salt stress. Therefore, we conclude that the U-box E3 ubiquitin ligase TaPUB1 positively regulates salt stress tolerance in wheat.
A barley mutant, 194, was observed to exhibit a leaf spot phenotype over the whole course of its growing period. In this study, the phenotype and antioxidant competence were studied in the lesion mimic mutant 194. Plant height was slightly higher in mutant 194 than in the wild type (WT). In addition, leaf spot per plant in mutant 194 was significantly higher than in WT. Antioxidant competence, as indicated by reactive oxygen species (ROS) accumulation, antioxidant enzyme activity, and the expression of antioxidant enzyme-encoding genes was also assessed in mutant 194. Compared to the WT, mutant 194 displayed a relatively higher accumulation of ROS, accompanied by lower activities of some antioxidant enzymes and downregulation of antioxidant enzyme-encoding genes. This demonstrated reduced antioxidant competence in mutant 194. The results suggested that this lower antioxidant competence of mutant 194 could lead to the accumulation of excessive ROS. This excess of ROS could induce programmed cell death and has the potential to promote disease resistance in mutant 194.
Two wheat near-isogenic lines (Nils; -GS (small grain size) and + GS (large grain size)) were obtained by backcrossing. We found that the grain volume and weight of + GS were significantly higher than those of -GS. There was a corresponding increase in grain yield associated with the + GS line. For analysis of causes, we investigated and compared the anatomic and physiological characteristics of two NILs during the grain filling stage. The bigger grain size in + GS likely resulted from the longer endosperm cells, which is related to the higher IAA content and expansin activity accompanied by the up-regulation of some expansin-related genes. For the higher grain weight of + GS, starch accumulation was higher in + GS than in -GS, which was consistent with relatively higher glucose (Glu), fructose (Fru), and sucrose (Suc) contents. Elevated sugar level may be correlated with sucrose synthase (SuSy) activity and up-regulation of GBSS I, SSS III, and SBE I. The amount of soluble protein in + GS grains also exceeded that in -GS grains, possibly because of increased NR, NiR, and GS activities and up-regulation of nitrogen assimilation and nitrate transporter genes in + GS grains. Furthermore, the photosynthetic rate was higher in + GS and -GS at the early filling stage before 21 DAA. The same trends were observed in sugar content (Suc, Fm, and Glu) and SPS activity. However, the increase in the rate of grain length and width in + GS plants at the late filling stage was significantly higher than that at the early filling periods. These suggest that high accumulation of dry matter (such as starch and protein) at early filling stage was the important factor in achieving the final increased size of wheat grains, besides cell expansion.
Adverse environmental conditions, including high temperature, often affect the growth and production of crops worldwide. F-box protein, a core component of the Skp1-Cullin-F-box (SCF) E3 ligase complex, plays an important role in abiotic stress responses. A previously cloned gene from wheat, TaFBA1, encodes a homologous F-box protein. A Yeast two-Hybrid (Y2H) assay showed that TaFBA1 interacted with other SCF proteins. We found that the expression of TaFBA1 could be induced by heat stress (45°C). Overexpression of TaFBA1 enhanced heat stress tolerance in transgenic tobacco, because growth inhibition was reduced and photosynthesis increased as compared with those in the wild type (WT) plants. Furthermore, the accumulation of H2O2, O2-, and carbonyl protein decreased and cell damage was alleviated in transgenic plants under heat stress, which resulted in less oxidative damage. However, the transgenic plants contained more enzymatic antioxidants after heat stress, which might be related to the regulation of some antioxidant gene expressions. The qRT-PCR analysis showed that the overexpression of TaFBA1 upregulated the expression of genes involved in reactive oxygen species (ROS) scavenging, proline biosynthesis, and abiotic stress responses. We identified the interaction of TaFBA1 with Triticum aestivum stress responsive protein 1 (TaASRP1) by Y2H assay and bimolecular fluorescence complementation (BiFC) assay. The results suggested that TaFBA1 may improve enzymatic antioxidant levels and regulate gene expression by interacting with other proteins, such as TaASRP1, which leads to the enhanced heat stress tolerance seen in the transgenic plants.
Salicylic acid (SA) plays an important role in signal transduction and disease resistance. In Arabidopsis, SA can be made by either of two biosynthetic branches, one involving isochorismate synthase (ICS) and the other involving phenylalanine ammonia-lyase (PAL). However, the biosynthetic pathway and the importance of SA remain largely unknown in Triticeae. Here, we cloned one ICS and seven PAL genes from barley, and studied their functions by their overexpression and suppression in that plant. Suppression of the ICS gene significantly delayed plant growth, whereas PAL genes, both overexpressed and suppressed, had no significant effect on plant growth. Similarly, suppression of ICS compromised plant resistance to Fusarium graminearum, whereas similar suppression of PAL genes had no significant effect. We then focused on transgenic plants with ICS. In a leaf-based test with F. graminearum, transgenic plants with an up-regulated ICS were comparable with wild-type control plants. By contrast, transgenic plants with a suppressed ICS lost the ability to accumulate SA during pathogen infection and were also more susceptible to Fusarium than the wild-type controls. This suggests that ICS plays a unique role in SA biosynthesis in barley, which, in turn, confers a basal resistance to F. graminearum by modulating the accumulation of H2O2, O 2 - and reactive oxygen-associated enzymatic activities. Although SA mediates systemic acquired resistance (SAR) in dicots, there was no comparable SAR response to F. graminearum in barley. This study expands our knowledge about SA biosynthesis in barley and proves that SA confers basal resistance to fungal pathogens.