Study on the Treatment of Refined Sugar Wastewater by Electrodialysis Coupled with Upflow Anaerobic Sludge Blanket and Membrane Bioreactor.

In this paper, refined sugar wastewater (RSW) is treated by electrodialysis (ED) coupled with an upflow anaerobic sludge blanket (UASB) and membrane bioreactor (MBR). The salt in RSW was first removed by ED, and then the remaining organic components in RSW were degraded by a combined UASB and MBR system. In the batch operation of ED, the RSW was desalinated to a certain level (conductivity < 6 mS·cm-1) at different dilute to concentrated stream volume ratios (VD/VC). At the volume ratio of 5:1, the salt migration rate JR and COD migration rate JCOD were 283.9 g·h-1·m-2 and 13.84 g·h-1·m-2, respectively, and the separation factor α (defined as JCOD/JR) reached a minimum value of 0.0487. The ion exchange capacity (IEC) of ion exchange membranes (IEMs) after 5 months of usage showed a slight change from 2.3 mmol·g-1 to 1.8 mmol·g-1. After the ED treatment, the effluent from the tank of the dilute stream was introduced into the combined UASB-MBR system. In the stabilization stage, the average COD of UASB effluent was 2048 mg·L-1, and the effluent COD of MBR was maintained below 44-69 mg·L-1, which met the discharge standard of water contaminants for the sugar industry. The coupled method reported here provides a viable idea and an effective reference for treating RSW and other similar industrial wastewaters with high salinity and organic contents.

Enhanced Anti-Biofouling Properties of BWRO Membranes via the Deposition of Poly (Catechol/Polyamine) and Ag Nanoparticles.

The surface modification of reverse osmosis (RO) membranes to improve their anti-biofouling properties is gaining increased attention. Here, we modified the polyamide brackish water reverse osmosis (BWRO) membrane via the biomimetic co-deposition of catechol (CA)/tetraethylenepentamine (TEPA) and in situ growth of Ag nanoparticles. Ag ions were reduced into Ag nanoparticles (AgNPs) without extraneous reducing agents. The hydrophilic property of the membrane was improved, and the zeta potential was also increased after the deposition of poly (catechol/polyamine) and AgNPs. Compared with the original RO membrane, the optimized PCPA3-Ag10 membrane showed a slight reduction in water flux, and the salt rejection declined, but enhanced anti-adhesion and anti-bacterial activities were observed. The FDRt of the PCPA3-Ag10 membranes during the filtration of BSA, SA and DTAB solution were 5.63 ± 0.09%, 18.34 ± 0.33% and 34.12 ± 0.15%, respectively, much better than those of the original membrane. Moreover, the PCPA3-Ag10 membrane exhibited a 100% reduction in the number of viable bacteria (B. subtilis and E. coli) inoculated on the membrane. The stability of the AgNPs was also high enough, and these results verify the effectiveness of poly (catechol/polyamine) and the AgNP-based modification strategy for the control of fouling.

Integrated ATAC-Seq and RNA-Seq Data Analysis to Reveal OsbZIP14 Function in Rice in Response to Heat Stress.

Transcription factors (TFs) play critical roles in mediating the plant response to various abiotic stresses, particularly heat stress. Plants respond to elevated temperatures by modulating the expression of genes involved in diverse metabolic pathways, a regulatory process primarily governed by multiple TFs in a networked configuration. Many TFs, such as WRKY, MYB, NAC, bZIP, zinc finger protein, AP2/ERF, DREB, ERF, bHLH, and brassinosteroids, are associated with heat shock factor (Hsf) families, and are involved in heat stress tolerance. These TFs hold the potential to control multiple genes, which makes them ideal targets for enhancing the heat stress tolerance of crop plants. Despite their immense importance, only a small number of heat-stress-responsive TFs have been identified in rice. The molecular mechanisms underpinning the role of TFs in rice adaptation to heat stress still need to be researched. This study identified three TF genes, including OsbZIP14, OsMYB2, and OsHSF7, by integrating transcriptomic and epigenetic sequencing data analysis of rice in response to heat stress. Through comprehensive bioinformatics analysis, we demonstrated that OsbZIP14, one of the key heat-responsive TF genes, contained a basic-leucine zipper domain and primarily functioned as a nuclear TF with transcriptional activation capability. By knocking out the OsbZIP14 gene in the rice cultivar Zhonghua 11, we observed that the knockout mutant OsbZIP14 exhibited dwarfism with reduced tiller during the grain-filling stage. Under high-temperature treatment, it was also demonstrated that in the OsbZIP14 mutant, the expression of the OsbZIP58 gene, a key regulator of rice seed storage protein (SSP) accumulation, was upregulated. Furthermore, bimolecular fluorescence complementation (BiFC) experiments uncovered a direct interaction between OsbZIP14 and OsbZIP58. Our results suggested that OsbZIP14 acts as a key TF gene through the concerted action of OsbZIP58 and OsbZIP14 during rice filling under heat stress. These findings provide good candidate genes for genetic improvement of rice but also offer valuable scientific insights into the mechanism of heat tolerance stress in rice.

Identification of Heat-Tolerant Genes in Non-Reference Sequences in Rice by Integrating Pan-Genome, Transcriptomics, and QTLs.

The availability of large-scale genomic data resources makes it very convenient to mine and analyze genes that are related to important agricultural traits in rice. Pan-genomes have been constructed to provide insight into the genome diversity and functionality of different plants, which can be used in genome-assisted crop improvement. Thus, a pan-genome comprising all genetic elements is crucial for comprehensive variation study among the heat-resistant and -susceptible rice varieties. In this study, a rice pan-genome was firstly constructed by using 45 heat-tolerant and 15 heat-sensitive rice varieties. A total of 38,998 pan-genome genes were identified, including 37,859 genes in the reference and 1141 in the non-reference contigs. Genomic variation analysis demonstrated that a total of 76,435 SNPs were detected and identified as the heat-tolerance-related SNPs, which were specifically present in the highly heat-resistant rice cultivars and located in the genic regions or within 2 kbp upstream and downstream of the genes. Meanwhile, 3214 upregulated and 2212 downregulated genes with heat stress tolerance-related SNPs were detected in one or multiple RNA-seq datasets of rice under heat stress, among which 24 were located in the non-reference contigs of the rice pan-genome. We then mapped the DEGs with heat stress tolerance-related SNPs to the heat stress-resistant QTL regions. A total of 1677 DEGs, including 990 upregulated and 687 downregulated genes, were mapped to the 46 heat stress-resistant QTL regions, in which 2 upregulated genes with heat stress tolerance-related SNPs were identified in the non-reference sequences. This pan-genome resource is an important step towards the effective and efficient genetic improvement of heat stress resistance in rice to help meet the rapidly growing needs for improved rice productivity under different environmental stresses. These findings provide further insight into the functional validation of a number of non-reference genes and, especially, the two genes identified in the heat stress-resistant QTLs in rice.

A flexible luminescence film with temperature and infrared response based on Eu2+/Dy3+ co-doped Sr2Si5N8 phosphors for optical information storage applications.

Deep-trap luminescent materials have attracted great attention for optical information storage applications. However, the flexible luminescence films based on red luminescence materials with temperature and infrared response are scarce. In this study, we have successfully developed various novel flexible red emitting films based on Eu2+/Dy3+ co-doped Sr2Si5N8 phosphors through screen-printing and spin-coating technologies, respectively. Interestingly, the fabricated flexible luminescence films exhibit unique temperature and infrared responsive properties for optical information storage by releasing photons in response to thermal or infrared stimulation. Notably, deep-trap red emitting Eu2+/Dy3+ co-doped Sr2Si5N8 phosphors are crucial for the optical information storage properties of the films. Two emission peaks of Sr2Si5N8:Dy3+ phosphors at 476 nm and 577 nm are observed under excitation at 345 nm, corresponding to the radiative transition occurs from the 4F9/2 level to the 6H13/2 and 6H15/2 levels of Dy3+. When Dy3+ and Eu2+ ions are co-doped in Sr2Si5N8, the energy transfer from Dy3+ to Eu2+ in Sr2Si5N8 matrix is found and the decay time confirms that Dy3+ ions can be acted as deep trap centers to storage photons. For Sr2Si5N8:Eu2+,Dy3+ phosphors and the corresponding flexible luminescence films, the specific patterns (for example apple and note patterns) are firstly recorded under NUV or blue light excitation and then reappear through thermal stimulation or near-infrared photo-stimulation (980 nm laser). This work not only validates the feasibility of Sr2Si5N8:Eu2+,Dy3+ phosphors as deep-trap red emitting luminescence materials, but also suggests the applications of flexible luminescence films for optical information storage.

Identification and molecular mapping of YrBm for adult plan resistance to stripe rust in Chinese wheat landrace Baimangmai.

KEY MESSAGE: A new adult plan resistance gene YrBm for potentially durable resistance to stripe rust was mapped on wheat chromosome arm 4BL in landrace Baimangmai. SSR markers closely flanking YrBm were developed and validated for use in marker-assisted selection. The wheat stripe rust pathogen Puccinia striiformis f. sp. tritici (Pst) frequently acquires new virulences and rapidly adapts to environmental stress. New virulences in Pst populations can cause previously resistant varieties to become susceptible. If those varieties were widely grown, consequent epidemics can lead to yield losses. Identification and deployment of genes for durable resistance are preferred method for disease control. The Chinese winter wheat landrace Baimangmai showed a high level of adult plant resistance (APR) to stripe rust in a germplasm evaluation trial at Langfang in Hebei province in 2006 and has continued to confer high resistance over the following 15 years in field nurseries in Hebei, Sichuan and Gansu. A recombinant inbred line population of 200 F10 lines developed from a cross of Baimangmai and a susceptible genotype segregated for APR at a single locus on chromosome 4BL; the resistance allele was designated YrBm. Allelism tests of known Yr genes on chromosome 4B and unique closely flanking marker alleles Xgpw7272189 and Xwmc652164 among a panel of Chinese wheat varieties indicated that YrBm was located at a new locus. Moreover, those markers can be used for marker-assisted selection in breeding for stripe rust resistance.

Identifying and Characterizing Conveyor Belt Longitudinal Rip by 3D Point Cloud Processing.

Real-time and accurate longitudinal rip detection of a conveyor belt is crucial for the safety and efficiency of an industrial haulage system. However, the existing longitudinal detection methods possess drawbacks, often resulting in false alarms caused by tiny scratches on the belt surface. A method of identifying the longitudinal rip through three-dimensional (3D) point cloud processing is proposed to solve this issue. Specifically, the spatial point data of the belt surface are acquired by a binocular line laser stereo vision camera. Within these data, the suspected points induced by the rips and scratches were extracted. Subsequently, a clustering and discrimination mechanism was employed to distinguish the rips and scratches, and only the rip information was used as alarm criterion. Finally, the direction and maximum width of the rip can be effectively characterized in 3D space using the principal component analysis (PCA) method. This method was tested in practical experiments, and the experimental results indicate that this method can identify the longitudinal rip accurately in real time and simultaneously characterize it. Thus, applying this method can provide a more effective and appropriate solution to the identification scenes of longitudinal rip and other similar defects.

A Dopamine/Tannic-Acid-Based Co-Deposition Combined with Phytic Acid Modification to Enhance the Anti-Fouling Property of RO Membrane.

Reverse osmosis (RO) membranes are widely used in the field of water treatment. However, there are inevitably various fouling problems during long-term use. Surface engineering of RO membranes, such as hydrophilic modification, has attracted broad attention for improving the anti-fouling performance. In this work, we constructed a green biomimetic composite modification layer on the surface of polyamide membranes using a dopamine (DA)/tannic acid (TA) co-deposited layer to bridge the polyamide surface and hydrophilic phytic acids (PhA). The DA/TA interlayer could firmly adhere to the RO membranes, reducing the aggregation of DA and providing abundant phenolic hydroxyl sites to graft PhA. Meanwhile, the anchored PhA molecule bearing six phosphate groups could effectively improve the superficial hydrophilicity. The membranes were characterized by the SEM, AFM, XPS, water contact angle test, and zeta potential test. After surface modification, the hydrophilicity, smoothness, and surface electronegativity were enhanced obviously. The flux and rejection of the virgin membrane were 76.05 L·m-2·h-1 and 97.32%, respectively. While the modified D2/T4-PhA membrane showed decent permeability with a water flux of 57.37 L·m-2·h-1 and a salt rejection of 98.29%. In the dynamic fouling test, the modified RO membranes demonstrated enhanced anti-fouling performance toward serum albumins (BSA), sodium alginates (SA), and dodecyl trimethyl ammonium bromides (DTAB). In addition, the modified membrane showed excellent stability in the 40 h long-term test.

Study on The Concentration of Acrylic Acid and Acetic Acid by Reverse Osmosis.

In the production of acrylic acid, the concentration of acrylic acid solution from the adsorption tower was low, which would lead to significant energy consumption in the distillation process to purify acrylic acid, along with the production of a large amount of wastewater. Reverse osmosis (RO) was proposed to concentrate the acrylic acid aqueous solution taken from a specific tray in the absorption tower. The effects of operating conditions on the permeate flux and acid retention were studied with two commercial RO membranes (SWC5 and SWC6). When the operating pressure was 4 MPa and the temperature was 25 °C, the permeate fluxes of two membranes were about 20 L·m-2·h-1. The acrylic acid and acetic acid retentions were about 80% and 78%, respectively. After being immersed in the acid solutions for several months, the characteristics of the two membranes were tested to evaluate their acid resistance. After six months of exposure to the acid solution containing 2.5% acrylic acid and 2.5% acetic acid, the retentions of acrylic acid and acetic acid were decreased by 5.7% and 4.1% for SWC5 and 4.9% and 2.2% for SWC6, respectively. The changes of membrane surface morphology and chemical composition showed the hydrolysis of some amide bonds.

A coupling technology of capacitive deionization and MoS2/nitrogen-doped carbon spheres with abundant active sites for efficiently and selectively adsorbing low-concentration copper ions.

Conventional techniques like electrodialysis, evaporation concentration cannot efficiently and selectively separate valuable heavy metals ions (VHMI) from electroplating rinse wastewater due to VHMI's low concentration and other ions' competitive adsorption. To realize the separation, a coupling technology was proposed which combines capacitive deionization (CDI) technique suitable for separating low-concentration ions and the few-layer molybdenum disulfide/N-doped carbon spheres (FL-MoS2/NCS) composite capable of selectively adsorbing copper ions (Cu2+), a representative VHMI. The FL-MoS2/NCS composite was successfully prepared by one-pot method and used as the cathode and anode in a CDI cell. Electrosorption experiments in the CDI cell showed that the FL-MoS2/NCS electrode (cathode) can efficiently adsorb low-concentration Cu2+ (23.63 mg/L) with a saturated adsorption capacity of 1199.63 mg/g at 0.8 V. In the competitive environment (Cu2+/Na+/Fe3+), the FL-MoS2/NCS electrode can selectively adsorb Cu2+ still with a high adsorption capacity of 1071.6 mg/g greatly outnumbering that of Na+ (199.2 mg/g) and Fe3+ (262.8 mg/g), despite the high concentrations of both NaCl (500 mg/L) and FeCl3 (80 mg/L). Furthermore, the XPS test and competitive adsorption results proved that the efficient and selective adsorption of the FL-MoS2/NCS electrode for Cu2+ was synergistically promoted by electrical double layer (EDL) and complexation of Cu2+ with FL-MoS2/NCS.

Virulence and Molecular Diversity in the Cochliobolus sativus Population Causing Barley Spot Blotch in China.

Spot blotch, caused by the fungal pathogen Cochliobolus sativus, is a limiting factor for barley (Hordeum vulgare) production in northeast China, which causes significant grain yield losses and kernel quality degradation. It is critical to determine the virulence diversity of C. sativus populations for barley resistance breeding and the judicious grouping of available resistance varieties according to the predominant pathotypes in disease epidemic regions. With little information on the barley pathogen in China, this study selected 12 typical barley genotypes to differentiate the pathotypes of C. sativus isolates collected in China. Seventy-one isolates were grouped into 19 Chinese pathotypes based on infection responses. Seventeen isolates were classified as pathotype 3, which has only been identified in China, whereas most (52 of 71) were classified as pathotype 1. All of the tested isolates had low virulence on the North Dakota (ND) durable, resistant line ND B112. Using 22 selected amplified fragment-length polymorphism (AFLP) primer combinations, genetic polymorphism was used to analyze 68 isolates, which clustered into three distinct groups using the unweighted pair group method average with the genetic distance coefficient. No relationship was found between the virulence of isolates and their origins. Isolates of the same pathotype or those collected from the same location did not group into clusters based on the AFLP analysis.

Grafting the Charged Functional Groups on Carbon Nanotubes for Improving the Efficiency and Stability of Capacitive Deionization Process.

In the capacitive deionization (CDI) process, the degradation of desalting performance is predominantly due to the co-ion expulsion effect and electrode oxidation. To overcome these complications, carbon nanotubes grafted with amine and sulfonic functional groups respectively were prepared and used as the CDI electrodes. The structural characterizations and performance tests confirmed that a uniform functional layer was formed on the surface of the modified electrodes and it enhanced the ion selectivity and wettability of the electrode surface. Moreover, the effects of the functional layer on the electrode stability were investigated by circulating CV tests and desalination tests. The positive shift value of the potential of zero charge (PZC) for the as-prepared electrodes was tested as a quantitative indication for their possible surface oxidation during cyclic tests. Analysis of the PZC variation and desalting performance demonstrated that the excellent desalting stability was achieved by the Cell N-S assembled with the ammoniated CNTs electrode as anode and sulfonated CNTs electrode as cathode. Because the functional layer could preserve the pores system on the modified electrodes and diminish the parasitic reactions that exacerbate the electrode oxidation. This work provides an effective strategy for promoting the electrode performance and prolonging the life of the electrode.

TabZIP74 Acts as a Positive Regulator in Wheat Stripe Rust Resistance and Involves Root Development by mRNA Splicing.

Basic leucine zipper (bZIP) membrane-bound transcription factors (MTFs) play important roles in regulating plant growth and development, abiotic stress responses, and disease resistance. Most bZIP MTFs are key components of signaling pathways in endoplasmic reticulum (ER) stress responses. In this study, a full-length cDNA sequence encoding bZIP MTF, designated TabZIP74, was isolated from a cDNA library of wheat near-isogenic lines of Taichung29*6/Yr10 inoculated with an incompatible race CYR32 of Puccinia striiformis f. sp. tritici (Pst). Phylogenic analysis showed that TabZIP74 is highly homologous to ZmbZIP60 in maize and OsbZIP74 in rice. The mRNA of TabZIP74 was predicted to form a secondary structure with two kissing hairpin loops that could be spliced, causing an open reading frame shift immediately before the hydrophobic region to produce a new TabZIP74 protein without the transmembrane domain. Pst infection and the abiotic polyethylene glycol (PEG) and abscisic acid (ABA) treatments lead to TabZIP74 mRNA splicing in wheat seedling leaves, while both spliced and unspliced forms in roots were detected. In the confocal microscopic examination, TabZIP74 is mobilized in the nucleus from the membrane of tobacco epidermal cells in response to wounding. Knocking down TabZIP74 with barley stripe mosaic virus-induced gene silencing (BSMV-VIGS) enhanced wheat seedling susceptibility to stripe rust and decreased drought tolerance and lateral roots of silenced plants. These findings demonstrate that TabZIP74 mRNA is induced to splice when stressed by biotic and abiotic factors, acts as a critically positive regulator for wheat stripe rust resistance and drought tolerance, and is necessary for lateral root development.

De Novo Analysis Reveals Transcriptomic Responses in Eriobotrya japonica Fruits during Postharvest Cold Storage.

Cold storage is the primary preservation method of postharvest loquat fruits. However, cold storage also results in many chilling injury physiological disorders called lignification, which decreases the quality and economic value of the fruits. Few studies to date have focused on the transcriptomic responses associated with lignification except lignin synthesis pathways. This study aimed to explore the changes of loquat transcriptome during long-term cold storage. Our results showed that the gene expression patterns were differed among the five stages. The differentially expressed genes (DEGs) in response to cold storage were more intense and complex in earlier stage. The membrane-related genes preferentially responded to low temperature and were followed by intracellular-located genes. The cold-induced pathways were mainly concerned with signal transduction and secondary metabolism (i.e., lignin, pectin, cellulose, terpenoid, carotenoid, steroid) in the first three stages and were chiefly related to primary metabolism in the later two stages, especially energy metabolism. Further investigation suggested that 503 protein kinases, 106 protein phosphatases, and 40 Ca2+ signal components were involved in the cold signal transduction of postharvest loquat fruits. We predicted a pathway including 649 encoding genes of 49 enzymes, which displayed the metabolisms of major sugars and polysaccharides in cold-stored loquat fruits. The coordinated expression patterns of these genes might contribute to the changes of saccharides in the pathway. These results provide new insight into the transcriptomic changes of postharvest loquat fruits in response to cold storage environment, which may be helpful for improving the postharvest life of loquat in the future.

Genetic analysis and location of a resistance gene for Puccinia striiformis f. sp. tritici in wheat cultivar Zhengmai 7698.

Wheat stripe (yellow) rust, caused by Puccinia striiformis West. f. sp. tritici (Pst), is one of the most destructive diseases in many wheat-growing countries, especially in China, the largest stripe rust epidemic area in the world. Growing the resistant cultivars is an effective, economic and environmentally friendly way to control this disease. Wheat cultivar Zhengmai 7698 has shown a high-level resistance to wheat stripe rust. To elucidate its genetic characteristics and location of the resistance gene, Zhengmai 7698 was crossed with susceptible variety Taichung 29 to produce F1, F2 and BC1 progeny generations. The genetic analysis showed that the stripe rust resistance in Zhengmai 7698 to Pst predominant race CYR32 was controlled by a single-dominant gene, named YrZM. Bulked segregant analysis and simple sequence repeat (SSR) markers were used to map the gene. Four SSR markers, Xbarc198, Xwmc179, Xwmc786 and Xwmc398 on chromosome 6BL were polymorphic between the parents and resistance, and susceptible bulks. A linkage genetic map was constructed using 212 F2 plants in the sequential order of Xwmc398, Xwmc179, YrZM, Xbarc198, Xwmc786. As this gene is effective against predominant race CYR32, it is useful in combination with other resistance genes for developing new wheat cultivars with resistance to stripe rust.

[Imaging Analysis in Cases with Clonorchiasis-Associated Cholangiocarcinoma].

Objective: To investigate the magnetic resonance imaging （MRI） and computed tomography (CT) features of clonorchiasis-associated cholangiocarcinoma, and provide reference for its clinical diagnosis. Methods: The CT and MRI （including magnetic resonance cholangiopancreatography, MRCP） data of 60 patients diagnosed to have cholangiocarcinoma（26 cases with clonorchiasis-associated cholangiocarcinoma, group A; 34 cases with simple cholangiocarcinomas, group B） by surgery or biopsy in two hospitals in Guangdong Province during July 2005 and June 2015 were collected. The tumor location, pathological types, imaging features, mode of enhancement, and the bile duct expansion were analyzed. Results: Imaging results showed that the tumor tended to occur in the right liver in group A（46.2%, 12/26） and in the left hepatic duct and the liver explorer in group B （61.8%, 21/34）（P<0.05）. The pathological types of tumor in both groups included the nodule/mass type (group A, 73.1%, 19/26; group B, 52.9%, 18/34), the infiltration type （15.4%, 4/26; 23.5%, 8/34）, and the cavity growth type（11.5%, 3/26; 23.5%, 8/34）（P>0.05）. Plain and enhanced CT and MRI results revealed no significant difference in tumor density, signal characteristics or the mode of enhancement between the two groups. MRCP results showed that the intrahepatic distal bile duct cystic dilatation, the intrahepatic bile duct cane soft tubular ectasia, the bile duct dilatation in the tumor, and the bile duct dilatation surrounding the tumor accounted for 61.5%（16/26）, 19.2% （5/26）, 50% （13/26） and 7.7%（2/26） in group A, and 8.8% （3/34）, 64.8% （22/34）, 20.6% （7/34） and 38.2% （13/34） in group B （P<0.05 for each of the four）， respectively. Conclusion: The clonorchiasis-associated cholangiocarcinoma has certain imaging characteristics. It is different from the simple cholangiocarcinomas in tumor location and intrahepatic bile duct dilatation.

TaNAC1 acts as a negative regulator of stripe rust resistance in wheat, enhances susceptibility to Pseudomonas syringae, and promotes lateral root development in transgenic Arabidopsis thaliana.

Plant-specific NAC transcription factors (TFs) constitute a large family and play important roles in regulating plant developmental processes and responses to environmental stresses, but only some of them have been investigated for effects on disease reaction in cereal crops. Virus-induced gene silencing (VIGS) is an effective strategy for rapid functional analysis of genes in plant tissues. In this study, TaNAC1, encoding a new member of the NAC1 subgroup, was cloned from bread wheat and characterized. It is a TF localized in the cell nucleus, and contains an activation domain in its C-terminal. TaNAC1 was strongly expressed in wheat roots and was involved in responses to infection by the obligate pathogen Puccinia striiformis f. sp. tritici and defense-related hormone treatments such as salicylic acid (SA), methyl jasmonate, and ethylene. Knockdown of TaNAC1 with barley stripe mosaic virus-induced gene silencing (BSMV-VIGS) enhanced stripe rust resistance. TaNAC1-overexpression in Arabidopsis thaliana plants gave enhanced susceptibility, attenuated systemic-acquired resistance to Pseudomonas syringae DC3000, and promoted lateral root development. Jasmonic acid-signaling pathway genes PDF1.2 and ORA59 were constitutively expressed in transgenic plants. TaNAC1 overexpression suppressed the expression levels of resistance-related genes PR1 and PR2 involved in SA signaling and AtWRKY70, which functions as a connection node between the JA- and SA-signaling pathways. Collectively, TaNAC1 is a novel NAC member of the NAC1 subgroup, negatively regulates plant disease resistance, and may modulate plant JA- and SA-signaling defense cascades.

Cotton gene expression profiles in resistant Gossypium hirsutum cv. Zhongzhimian KV1 responding to Verticillium dahliae strain V991 infection.

Verticillium wilt of cotton (Gossypium hirsutum) is a widespread and destructive disease that is caused by the soil-borne fungus pathogen Verticillium dahliae (V. dahliae). To study the molecular mechanism in wilt tolerance, suppression subtractive hybridization (SSH) and dot blot techniques were used to identify the specifically expressed genes in a superior wilt-resistant cotton cultivar (G. hirsutum cv. Zhongzhimian KV1) after inoculation with pathogen. cDNAs from the root tissues of Zhongzhimian KV1 inoculated with V. dahliae strain V991 or water mock were used to construct the libraries that contain 4800 clones. Based on the results from dot blot analysis, 147 clones were clearly induced by V. dahliae and selected from the SSH libraries for sequencing. A total of 92 up-regulated and 7 down-regulated non-redundant expressed sequences tags (ESTs) were identified as disease responsive genes and classified into 9 functional groups. Two important clues regarding wilt-resistant G. hirsutum were obtained from this study. One was Bet v 1 family; the other was UbI gene family that may play an important role in the defense reaction against Verticillium wilt. The result from real-time quantitative reverse transcription polymerase chain reaction showed that these genes were activated quickly and transiently after inoculation with V. dahliae.

[Changes of DIMBOA contents in resistant and susceptible wheat near-isolines infected by Puccinia striiformis f. sp. tritici].

With two sets of wheat near-isolines having different genetic background as test materials, this paper studied the dynamics of their DIMBOA (2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one) contents during Puccinia striiformis f. sp. tritici infection. It was revealed that in un-inoculated plants, no significant difference was observed in DIMBOA contents among various resistant and susceptible inbred lines within the same set. But, at the initial stage of infection, the DIMBOA contents in all resistant isolines displayed a quicker and greater increase, resulting in a significantly higher content of DIMBOA in resistant isolines than in susceptible one throughout the period of disease development. The infection ultimately led to a decline of DIMBOA contents in all infected plants, but the decrement was significantly less in resistant lines than in susceptible one. It could be concluded that DIMBOA was associated with the monogenic resistance to Puccinia striiformis f. sp. tritici in wheat. The study of DIMBOA dynamics in plants suffered from diseases and pests would be useful for understanding the mechanism of resistance, and the screening and breeding of crop varieties with multiple-resistance.