Auxin export carrier PIN-FORMED (PIN) family members mainly mediate auxin polar transport and asymmetric distribution. To better understand Dendrobium catenatum PIN (DcPIN) gene family, the present study performed genome-wide identification of DcPIN members, and further analyzed their phylogenetic relationships, gene structure, protein conserved motifs and domain composition, promoter cis-acting element, and expression profiles of both tissues and stress responses by means of bioinformatics and transcriptome data. The results showed that D. catenatum contained 21 DcPIN members that were divided into 7 clades. Among them, PIN9 clade was specific to monocot and contained high number of DcPIN9 genes in D. catenatum, which might be strongly relevant to its unique lifestyle and living environment. The upstream DcPIN promoters were rich in cis-regulatory elements related to hormones, light, development, and stress response. Transcriptome data showed the expression of DcPIN genes in different tissues could be totally divided into specific expression and constitutive expression. Transcriptome and qRT-PCR analysis under different treatments showed DcPIN1a/9a/9d/9g were in response to cold, DcPIN9a/9f/9h in response to drought, DcPIN3a/9a/9d/9h in response to JA, and DcPIN1c/3a/9a in response to the infection of Southern Blight pathogen Sclerotium delphinii. This result provides a theoretical basis for further investigating the function of D. catenatum PIN genes in the growth and development and environmental adaptation.

Ovate family proteins (OFPs) is a plant-specific transcription factor gene family, which plays an important role in low temperature stress response. In order to explore the OFP gene family members in wheat (Triticum aestivum), as well as the expression characteristics under cold stress, in this study, the members of the OFP family were identified and bioinformatics analysis was carried out in the whole genome of wheat, the expression pattern of TaOFPs in different tissues under low temperature stress were analyzed based on RNA-seq. The results showed that a total of 100 TaOFPs were identified, which were evenly distributed on A, B and D subgenomes. Wheat, rice (Oryza sativa) and Arabidopsis OFPs were divided into 6 subgroups based evolutionary analysis, and the OFP genes in gramineae were more conservative during evolution. The results of promoter elements analysis indicated that a large number of hormone related and abiotic stress response cis-acting elements, such as MeJA responsive elements, ABA responsive elements, low temperature responsive elements and drought responsive elements existed in promoter sequences of TaOFPs. The expression analysis revealed the tissue and stage specific expression patterns of TaOFPs. Under freezing stress, 25 TaOFPs were differentially expressed in cold acclimation and freezing specificity, TaOFP4-1D, TaOFP10-2B, TaOFP27-4D, TaOFP31-5A and TaOFP33-5D showed opposite expressed pattern in cold acclimation and freezing and un-cold acclimation and freezing treatments, suggested that these genes may involved in regulation of cold resistance of wheat. This study provides reference for further exploring the function of TaOFP family members and analyzing its regulatory mechanism in low-temperature stress.

The NAC (NAM, ATAF, and CUC) transcription factors (TFs), which constitute one of the largest plant-specific transcription factor family, play an important role in resisting stress response, regulating plant growth and development, participating in organ model building, auxin transduction and leaf apoptosis, etc. In order to identify the foreign NAC086 gene of Chinese cabbage (Brassica campestris ssp. pekinensis)-cabbage (B. oleracea var. capitata) double haploid translocation line AT1-18, the cloning and expression of NAC086 genes were carried out from the translocation line AT1-18 and its parents by PCR, RT-PCR (reverse transcription-PCR) and qRT-PCR (real-time quantitative PCR) methods. The results showed that the gene Bol034440 was amplified with the specific primers in cabbage and translocation line, however, the gene Bra006392 was only obtained in Chinese cabbage. Sequence analysis showed that the identity was as high as 99% between the sequence of PCR product from the translocation line using Bol40-1 primers and CDS sequence of gene Bol034440. It was proved that Bra006392 gene of Chinese cabbage was replaced by Bol034440 gene of cabbage in the translocation line. RT-PCR analysis showed that there was almost no Bol034440 expression in the different tissues of Chinese cabbage, but the high relative expression was in the different tissues of the translocation line, followed by roots>leafs>buds>flowers>stems, with significant difference between roots and flowers, buds, stems. Bra006392 had almost no expression in the tissues (except roots) of the translocation line, but had the highest expression in the leaves of Chinese cabbage, which was significantly higher than that in other tissues. Bra008567 had high expression level in different tissues of Chinese cabbage and translocation lines, and the highest expression was in the root of Chinese cabbage, which was significantly higher than other tissues. Whereas, the highest expression was in the leaves of the translocation line, which was also significantly higher than other tissues except roots. There were significant differences between the two materials and from other tissues. qRT-PCR analysis showed that Bol034440 and Bra008567 responding to exogenous auxin treatment were negative and responding to the salt treatment was positive, the response time of both was 2 h after treatment, and Bol034440 was dominant in the response process. The results offered insight into the functional validation of NAC086 and studying the interaction and regulation of cabbage NAC086 gene in the genetic background of Chinese cabbage.

B-box (BBX) transcription factor plays an important role in the photomorphogenesis of seedlings, regulation of flowering photoperiod, avoidance of light and other growth and developmental processes, as well as in response to the biotic and abiotic stresses. In this study, a BBX protein was obtained from Solanum pennellii and named as SpBBX1 (Gene ID: Sopen02g034260). In order to study its function, the physicochemical properties, protein structure, phylogenetic tree, subcellular localization and prokaryotic expression were analyzed. The results showed that SpBBX1 contained a complete open reading frame of 1 173 bp, encoding 390 amino acids, and was located in the nucleus; phylogenetic tree analysis showed its amino acid sequence was closely related to cultivated tomato protein SlCONSTANS1 (Gene ID: Solyc02g089540) and potato protein StB-box1 (Gene ID: PGSC0003DMP400017796); SDS-PAGE and Western blot results showed that the molecular weight of recombinant SpBBX1 protein was about 48 kD; qRT-PCR analysis found that SpBBX1 was expressed in stem, leaf, and flower, with the highest expression in leaf. The prokaryotic recombinant strain Escherichia coli BL21::pET-30a-SpBBX1 showed significantly lower growth than the control strain in response to NaCl or polyethylene glycol (PEG) stress (P<0.05). These results suggested that SpBBX1 gene may have a negative regulatory effect in response to stress, the data could provide a theoretical basis for further research on plant BBX function.

MYB transcription factors play an important role in plant growth and development and resistance to stress. In order to carry out the functional study of the tobacco (Nicotiana tabacum) NtMYB4a gene and the creation of a new germplasm, this study took the tobacco NtMYB4a as the target gene, selected two targets Y1 and B1 on exons 1 and 3 based on its CDS sequence, synthesized oligo dimers separately and connected with CRISPR vector, transformed Escherichia coil competent DH5α, extracted the plasmid and sequenced, and the correct Y1-1 and B1-1 were digested with LguⅠ and then recombined with T₄ ligase. The CRISPR/Cas9 editing system double target knockout vector was successfully constructed, and through Agrobacterium tumefaciens mediated leaf disc method to transform tobacco. After PCR and sequencing, 29 positive plants containing Cas9 and Hyg resistance genes and target genes were obtained, and the positive rate was 24.37%. The PCR products of 29 positive tobacco strains were sequenced. Among them, 15 strains had different degrees of mutations at the target and non-target sites. There were 4 mutation types, and the mutation rate was 51.72%. The results showed that plants in the edited NtMYB4a T₀ generation appeared dwarfing and flower color variation, and some even died. qRT-PCR analysis showed that the expression of NtMYB4a gene was down-regulated in the flowers, stems and leaves of tobacco plants of the T₀ generation to varying degrees. This study provides basic information for the further study on the function of NtMYB4a and the molecular regulation mechanism of NtMYB4a.

Gibberellin (GA) is a type of diterpene plant hormone, which plays an important role in the physiological development of plants. GA can promote the plant extension and affect the production of dry matter in sink organs. It can also activate α-amylase activity to promote catalyzes the degradation of energy storage substances and promotes the break of plant dormancy. For example, the increase of GA content can promote the germination of barley and make it enter the development stage earlier. GA also has an effect on fruit development and maturity, it can also delay leaf senescence and inhibit tuber formation. Gibberellin 20- oxidase (GA20ox) enzyme is the key rate-limiting enzyme in the final stage of GA synthesis pathway. It exercises catalytic regulation function in the final stage of GA synthesis and promotes the production of GA20 and GA9, those are precursors of active GA1 and GA4. GA20ox gene has a close influence on the activity of GA20ox enzyme and is closely related to GA. ABA (abscisic acid) is a 15-carbon sesquienene compound, which can effectively promote the development and growth of various plants. It plays an important role in seed germination, maturation and dormancy, fruit maturation. It can bring huge economic benefits and can effectively increase crop yields. There are 2 ways to synthesize ABA in plants, one is the indirect pathway, the C15 pathway, and the other is the direct pathway, which also can be called the carotenoid pathway. The synthesis of ABA in higher plant tissues is mainly achieved through indirect pathways. 9-cis epoxy carotenoid dioxygenase (NCED) is the rate-limiting enzyme in the process of indirect ABA synthesis and regulation. Auxin (IAA) is an endogenous hormone containing an unsaturated aromatic ring and an acetic acid side chain. IAA is a signal transduction compound that promotes and affects plant development and physiological changes. It plays an important role at every moment of development, affecting the division, differentiation and elongation of plant cells, as well as various physiological activities of plants, such as apical dominance, light orientation and gravity, and induces many division-related genes expression. Indoleacetic acid (AUX)/IAA auxin response protein can negatively regulate auxin synthesis. In this study, enzyme linked ELISA was used to determine the changes in GA, ABA, and IAA content in Fritillaria thunbergii during bulb development. As the bulb develops, GA content showed a downward trend. ABA showed an upward trend, IAA generally showed a downward trend. Using homologous cloning combined and RACE technology, Fritillaria thunbergii GA20ox (GenBank No. MW238816), NCED (GenBank No. MW238817) and IAA (GenBank No. MW238818) were successfully cloned. Bioinformatics analysis showed that the full length of the sequence of GA20ox gene was 1 490 bp, the open reading frame was 1 122 bp, and encoded 373 amino acids; the full length of the sequence of NCED gene was 2 270 bp , and the open reading frame was 1 800 bp, which encoded 599 amino acids; the full length of the sequence of IAA gene was 1 255 bp, with an open reading frame of 864 bp, encoding 287 amino acids. qRT-PCR analysis showed that the GA20ox, NCED, IAA genes expression in bulbs at different developmental stages correlated with GA, ABA, and IAA. The correlation analysis showed that GA20ox, NCED and GA, ABA content were significantly positively correlated (P<0.01), IAA and IAA content was a very significant negative correlation (P<0.01). This study provides a theoretical basis for the study of the functions of GA20ox, NCED, IAA genes in GA, ABA and IAA metabolism, and provides references for further exploring the molecular mechanisms of GA20ox, NCED and IAA genes in the bulb development process of F. thunbergii.

Heat shock transcription factor 1 (HSF1) is an important transcription factor that initiates heat shock protein gene expression. Further study on HSF1 will help to clarify the regulatory mechanism of HSF1 on heat stress response. In this study, reverse transcription-PCR (RT-PCR) was used to clone the full-length CDS of HSF1 from Chinese Holstein cow (Bos taurus), and bioinformatics was used to analyze the biological characteristics of the protein. The results showed that 3 splice variants were successfully cloned, named HSF1-AS1 (GenBank No. MW401766), HSF1-AS2 (GenBank No. XM_005215151.4), and HSF1-AS3 (GenBank No. MW401767). The splicing patterns of the 3 variants were exon skipping, intron retaining, and alternative 3' splice sites. The ORF analysis showed that the 3 splice variants of HSF1 encoded 311, 553 and 517 aa, respectively. The RNA-seq data of breast tissue in previous study was analyzed, and the results showed that the expression of HSF1-AS2 was the highest (P<0.01), and the expression of HSF1-AS1 was the lowest (P<0.01). The results of qRT-PCR showed that the expression levels of HSF1-AS1 and HSF1-AS2 were both up-regulated in heat stressed mammary epithelial cells. The binding site analysis of splicing factors showed that the SNP (18948 C>T) of exon 11 of HSF1 gene was just in the potential region of exonic splicing enhancer (ESE), which might be associated with the formation of HSF1-AS3. The phylogenetic analysis showed that bovine HSF1 amino acid sequence had high homology and close genetic distance with that of goats (Capra hircus). The present study provides a reference for further elucidating the regulation mechanism of HSF1 gene expression.

Fatty acid compositions are crucial indicators of milk quality in dairy cow. Long chain fatty acid (LCFA), especially polyunsaturated fatty acids (PUFA) are beneficial in reducing the risk of cardiovascular disease, cancer, and type 2 diabetes in humans (Homo sapiens). However, the metabolic mechanism of LCFA in mammary gland is still unknown. Solute carrier family 27 member 6 (SLC27A6) is a transmembrane protein that could enhance the uptake of LCFA into cells, thus regulating downstream fatty acid (FA) metabolic pathways. But the relationship between SLC27A6 and fatty acid metabolic genes is still unclear. In this study, SLC27A6 knockdown in bovine (Bos taurus) mammary epithelial cells (BMECs) was accomplished by RNA interference to further assess the function of SLC27A6. The relative mRNA expression level of genes related to lipid metabolism after SLC27A6 knockdown in BMECs was analyzed by real-time quantitative PCR, and the protein level of SLC27A6 was analyzed by Western blot. The effect of SLC27A6 knockdown on triglyceride (TG) content and FA composition in BMECs were determined.The result showed that the mRNA and protein levels of SLC27A6 were decreased in SLC27A6-Bos-915 group compared with the control group. And knockdown of SLC27A6 dramatically downregulated the mRNA abundance of genes associated with FA activation long-chain acyl-CoA synthetase 4 (ACSL4), fatty acid transporter CD36 and oxidation carnitine palmitoyl transferase 1A (CPT1A), while abundance of genes associated with transcription regulation peroxisome proliferative activated receptor gamma (PPARG), fatty acid binding protein 3 (FABP3), and fatty acid desaturase 2 (FADS2) were upregulated. In addition, SLC27A6 was silenced, the intracellular content of TG and the percentage of oleic acid (C18∶1cis9) and arachidonic acid (C20∶4cis5,8,11,14) were higher, whereas that of palmitic acid (C16∶0) and stearic acid (C18∶0) were lower. Overall, these results could provide strong support for a central role of SLC27A6 in the regulation of lipid metabolism in BMECs, and have an important guiding significance to improving milk quality by breeding programs.

During the development of ovarian follicles, gap junctions between oocytes and surrounding granulosa cells mediate intercellular communication and material transport. Gap junction internalization refers to the clathrin-mediated endocytosis (CME) process. In order to study the effect of CME-related genes on ovary function of Congjiang Xiang pig (Sus scrofa), transcriptome sequencing technology was used to analyze the expression of CME-related genes and the alternative splicing of transcripts in Congjiang Xiang pigs ovaries at estrus stage by Limma, DESeq2, rMATs softwares and reverse transcription PCR (RT-PCR) method. Transcriptome changes at diestrus stage were used as controls. As a result, 8 CME genes were detected in the ovaries of Congjiang Xiang pigs, including DAB adaptor protein 2 (DAB2), adaptor related protein complex 2 subunit μ1 (AP2M1), clathrin light chain B (CLTB), clathrin light chain A (CLTA), dynamin-1 (DNM1), myosin Ⅵ (MYO6), dynamin-2 (DNM2) and clathrin heavy chain (CLTC). Among them, the differentially expressed genes were DAB2, AP2M1 and CLTB. Except for CLTB, the other 7 genes produced different alternative splicing events between estrous and diestrous ovaries, and the 7 transcripts produced by these alternative splicing events were the new transcripts not included in the Ensembl database up to now. It showed that alternative splicing was an important regulation mode of ovary in Congjiang Xiang pigs at estrus stage, and a specific network of protein interaction was formed by producing new transcripts and proteins during CME. The results of this study indicated that the internalization of gap junction was regulated by the expression of CME-related genes and splicing of transcripts at transcription and post-transcription levels, thus regulating the ovarian function of Congjiang Xiang pig. These researches would help to understand of the post-transcriptional regulation process and the molecular regulation mechanism of porcine ovarian function.

In recent years, with the increasing intensification of laying duck (Anas platyrhynchos) cultivation, the effect of heat stress caused by constant high temperature in summer poses a serious challenge to safety production. To elucidate the effect of heat stress on hepatic protein expression and to explore the function of differential protein genes in laying duck, in this study, Shaoxing ducks at the peak laying period (245-day old) were selected for heat stress treatment and liver tissues were collected. A total of 98 differentially expressed proteins (DEPs) were identified by isobaric tags for relative and absolute quantification (iTRAQ) and LC-MS/MS, with significantly upregulation of heat shock protein 60 (HSP60)(P<0.01). KEGG analysis showed that DEPs enriched in 15 metabolic pathways after heat stress. Glycolysis and gluconeogenesis, tricarboxylic acid cycle and pyruvate may be related to the effects of heat stress. GO analysis showed that DEPs were involved in translation extension, glucose catabolism process, glycolysis. HSP60-siRNA was transfected into duck hepatocytes after screening and optimization. Compared with negative control (NC) group, HSP60 gene expression was decreased by 75.69% (P<0.01), cytochrome coxidase gene (CCO)(P<0.01), and stress-activated protein kinase gene (SAPK) were significantly increased (P<0.01), protein kinase gene (PKB) was significantly decreased (P<0.01). There was no significant difference in the expression of tumor necrosis factor-related apoptosis inducing receptors gene (TRAIL-Rs)(P>0.05). The results showed that HSP60 was significantly increased in the liver of laying ducks under acute heat stress and inhibited apoptosis by regulating the expression of key genes of apoptotic signaling pathways. It is helpful to prevent and control the occurrence of heat stress by preliminarily exploring the mechanism of heat stress occurrence in laying ducks.

Mulard duck is an inter-genus hybrid product of Muscovy duck (Cairina moschata) and domestic duck (Anas plalyrhynchas var. domestica),which has strong heterosis but no reproductive ability. In actual production, it is necessary to raise the parents of Mulard ducks, and with the help of artificial insemination technology, the process is cumbersome and the feeding management cost is high, which severely restricts the development of Mulard duck production. Due to the particularity of the sterile traits of Mulard ducks, the analysis of differentially expressed genes in the ovarian tissues of Mulard ducks has not been reported. The information on related genes in the GenBank sequence database is relatively scarce. The genetic basis of infertility needs further research. Transcriptome sequencing (RNA-seq) technology could not only be used for analysis of tissue changes after virus infection, but also for gene mining and functional annotation. In order to explore the molecular mechanism of genes related to ovarian hypoplasia and infertility in Mulard duck, transcriptome sequencing was performed on the ovarian tissues of Mulard ducks and Pekin ducks, the differentially expressed genes related to ovarian differentiation and development were screened, and the genes were annotated with Gene Ontology (GO) and KEGG, and then the qRT-PCR was used to verify the sequencing results. A total of 43.84 Gb clean data and 193 535 Unigenes were obtained in the sequencing. A total of 89 differentially expressed genes related to ovarian development, sex hormone synthesis and germ cell differentiation and development were found between two types of ducks, among them 17 genes were down-regulated, 72 genes were up-regulated in Mulard ducks, Go functional annotation differential genes were enriched in 591 GO terms, in which the significantly enriched calcium-mediated signal transduction was related to germ cell differentiation and development. KEGG analysis showed that differentially expressed genes are enriched in 15 signal pathways, Including glycosides biosynthesis-ganglion series, steroid hormone biosynthesis pathway and tyrosine metabolism related to the synthesis and secretion of sex hormones. The results of qRT-PCR showed that the expression trends of up-regulated and down-regulated genes in Mulard ducks were consistent with the transcriptome sequencing results, indicating that the transcriptome sequencing data was more reliable. This study provides theoretical reference for exploring the differentiation mechanism of the special reproductive system of Mulard ducks.

CRISPR/Cas9 is a gene editing technology for specific DNA modification of targeted genes. Based on the simplicity of design, low cost, and high efficiency, CRISPR/Cas9 system has been extensively used in mammal for gene function study. It has been well developed in model fish and freshwater fish for gene function analysis through gene knockout method, but there were few studies on marine fish species, especially on flatfish. Olive flounder (Paralichthys olivaceus) is an important maricultured fish in China with high economic value. In this study, low microinjection concentrations of Cas9 message RNA (Cas9 mRNA) (250 ng/μL) and guide RNA (gRNA) (100 ng/μL) were firstly administrated to edit genes related to gonadal and muscle development, including myogenic differentiation (myod), adaptor-related protein complex 3 (ap3), R-spondin 1 (rspo1), and dynein axonemal light intermediate chain 1 (dnali1) (dnali1-part A and dnali1-part B) in olive flounder, respectively. Two gRNAs for dnali1-part A and dnali1-part B, and one gRNA for the other genes were designed to be used for the editing, respectively. The results showed that no mutants were detected in the newly hatched larvae of the rspo1, myod and dnali1-part A gene editing groups, and the mutation rates of the ap3 and dnali1-part B groups were no more than 14.3% and 42.9%~45%, respectively. And then, the higher injection concentrations of Cas9 mRNA (1 500 ng/μL) and gRNA (1 000 ng/μL) were used for the genes editing. Under the condition, the mutation rate of dnali1-part B increased to 65%, and the mutation rate of of individual detection increased from 10%~20% to 80%~90%. The marker gene dead end (dnd) of primordial germ cells, doublesex and mab-3 related transcription factor 1 (dmrt1), and hydroxysteroid (17-beta) dehydrogenase 1 (17β-Hsd1) genes with 2 gRNAs were further edited by using higher concentrations of Cas9 mRNA and gRNA, and the mutation rates of these genes were 60%~80% at hatched stage. The results also showed that the editing efficiency at low concentration condition with one gRNA site (14.3%~45%) was lower than those at high concentration condition with 2 gRNA sites (60%~80%). This study established a CRISPR/Cas9 gene editing method in olive flounder primarily, and would provide a reference for its application in the flatfish.

Acrylamide (ACR), one of the critical environmental stressors, is widely used in soil stabilization, water treatment, industrial products, and certain foods, which toxicity was attracting global attention. This study focused on the toxic effects of ACR in non-neural organs such as the intestines. This study used 3-day-old zebrafish (Danio rerio) and laboratory-grown zebrafish intestine cells (ZFI) as experimental materials. Coagulant fluorescence markers and qRT-PCR were used to check some stress response genes, glutathione-disulfide reductase (GSR), X-box binding protein 1 (xbp1u), recombinant aquaporin 4 (aqp4), and calcium/calmodulin-dependent-protein (CaMK2g2) for expression testing. The 4 genes' functions were related to reaction mechanisms such as oxidative stress, endosurgen network stress, permeable pressure stress, and stress signal-transducing. The coagulation point imprinting results showed that the maackia amurensis lectin Ⅱ(MAL-Ⅱ), wheat germ agglutini (WGA), and peanut agglutinin (PNA) tricoagulant bars were at 12.5 and 25.0 mmol/L tolerances than the 0 mmol/L ACR tolerance. The bands showed varying degrees of shallow changes in zebrafish and ZFI in 45~60 kD, where the changes in the coagulant bands of ZFI at a tolerance concentration of 25.0 mmol/L were more pronounced. Besides, at a concentration of 25.0 mmol/L ACR, ACR toxicity caused the most significant damage to the body (18 h) and cells (5 h), and the above 4 genes associated with stress response showed that for ZFI, aqp4 and xbp1u showed very high significant expression (P<0.01), CaMK2g2 and GSR showed significant high expression in ZFI (P<0.05); For zebrafish, the expression of aqp4 increased significantly (P<0.05), xbp1u and GSR showed extremely high significant expression (P<0.01), and CaMK2g2 showed no significant change (P>0.05). The above results showed that ACR toxicity was systemic when it caused damage to cells, and the ACR toxicity mechanism was closely related to the non-biological stress response mechanism. Therefore, this study's significance lied in revealing the fish bodies' stress response mechanism to ACR stress. Multi-level interpretation of its toxicity mechanism would be conducive to protect fish and other aquatic organisms from ACR toxic intrusion to meet the growing aquatic food safety needs of China and the world's population.

Cardamine violifolia is a selenium hyperaccumulator, which was discovered to be medicinal and edible by Chinese scientists. It can convert inorganic selenium into selenocysteine and accumulate selenium in plant. Microorganisms can transform selenium forms, and this transformation may be beneficial to selenium enrichment in C. violifolia. However, there are few studies on the endophytes of C. violifolia. In this work, the endophytes from C. violifolia were isolated and identified, and the selenium resistance was investigated. Finally, 6 endophytic bacteria were purified from C. violifolia and 4 strains were capable of producing nano-selenium by metabolizing 0.01 mol/L sodium selenite. Enterobacter sp. SX-18 was identified to be resistant to a concentration of up to 0.20 mol/L sodium selenite, and was able to transform 46.96% of 0.02 mol/L sodium selenite into nano-selenium in 24 h. A total of 5 endophytic fungi were isolated and identified. All of them displayed the ability to metabolize 0.01 mol/L sodium selenite, and Colletotrichum sp. SZ-5 was identified to be resistant to 0.16 mol/L sodium selenite and was able to transform 19.34% of 0.02 mol/L sodium selenite into nano-selenium in 48 h. The present study provides more endophytic microbial resources for investigating the interaction between plants and microorganisms and biological remediation of selenium contamination aera.

BBM (BABY BOOM), transcription factors of the AP2/ERF family are key regulators of plant cell totipotency. The BBM gene acts as a marker gene for parthenogenesis and plays a significant role to create the artificail apomixis in rice (Oryza sativa). The main objective of this review is to present recent advances in biotechnology of the BBM gene, a update on the current status on genetic mechanism of apomixis of Kentucky bluegrass (Poa pratensis) and its application in apomixis, in an aim to provide insights into breeding new cultivars and shortening the process of seed domestic production of Kentucky bluegrass via apomixis.

Plant pathogenic agents seriously threaten the yield and quality of crop. Establishing efficient and accurate pathogen diagnosis technology is critical for disease control. Metagenomic sequencing technology based on next generation sequencing (NGS) platform is an important tool for plant disease identification. However, the application of NGS in the rapid detection of plant pathogens is restricted by the disadvantages of high cost, long experimental period and bulky equipment. Nanopore sequencing technology developed by Oxford Nanopore Technology Co., Ltd. (ONT)(Oxford, United Kingdom) is a new sequencing platform. Compared with the NGS platform, it has advantages such as low cost, short experimental period and easy to use. It is suitable for field detection and has been used in pathogen detection. In this paper, the principle of ONT Nanopore sequencing technology was introduced, and the applications and challenges of this technology in plant pathogen detection were summarized, which provides reference for the further application and improvement of this technology in plant pathogen detection.

Genetically modified Brassica napus NS-B50027-4 is a new variety containing a high proportion of ω3 fatty acids and LC-ω3 fatty acids approved by the Australia-New Zealand Food Standards Agency. So far there is no literature report on the detection method of this new genetically modified B. napus variety. Therefore, it is necessary to establish a qualitative and quantitative detection method for this species. In this study, primers and probes were designed according to the internal reference gene HMG (high mobile group protein) of B. napus and A02 chromosome of transgenic B. napus NS-B50027-4, respectively. The specificity, sensitivity and accuracy of the primers and probes were determined by conventional PCR and qPCR technology to determine the detection limit and quantification limit of the detection method. The experimental results show that the two designed primers could only amplify the target, the detection limit of hmg primer can reach 5 copies/μL, and the detection limit of A02dn2 primer is 1 copy/μL. Therefore, the established qualitative and quantitative detection method of genetically modified B. napus NS-B50027-4 has high specificity and selectivity, excellent sensitivity and accuracy. The research results provide technical support for the qualitative and quantitative detection of genetically modified B. napus NS-B50027-4.

Fusarium wilt of watermelon caused by Fusarium oxysporum f. sp. niveum (FON) is the main disease of watermelon across all major watermelon-growing regions in China. Therefore, the establishment of a rapid detection method of FON is quite important for the diagnosis, prevention and control of Fusarium wilt of watermelon. In this study, using the specific DNA sequences of FON as the target, a set of sensitive and specific loop-mediated isothermal amplification (LAMP) primers were designed, and combined with the rapid DNA extraction method, a rapid LAMP detection assay for FON was established. The results of primer specificity experiments showed that only FON-0, FON-1 and FON-2 showed yellow-green color for LAMP detection, and the agarose gel electrophoresis results of LAMP products showed trapezoidal bands, indicating that the primers had high specificity. The sensitivity detection results showed that the lower limit of detection of the LAMP assay for FON-1 genomic DNA was 10 pg/μL, and for FON-1 content in plants was 5×10² spores/g. The results of potting experiments showed that the assay could make a correct judgment on whether watermelon seedlings were infested by FON, using root tissues as samples. In this assay, from the beginning of DNA extraction to the detection results, only about 90 min was needed, and the pathogenic mycelia, the tissues of the plants could be used as detection materials. The results of LAMP reaction were discernible to the naked eye, with simple operation, strong specificity, high sensitivity, stability and wide applicability. It provides technical support for rapid molecular diagnosis of FON in the field.

Bovine mastitis is the most harmful common disease in dairy farms, which seriously affects the healthy development of dairy industry. Bacterial infection is main cause of bovine mastitis. Staphylococcus aureus is one of the most common causative pathogen which causing bovine mastitis. Therefore, the rapid detection method for Staphylococcus aureus is of great significance to realize the early prevention of mastitis in dairy cows. The loop-mediated isothermal amplification (LAMP) technique is a new nucleic acid amplification method that could quickly detect target DNA under isothermal conditions. In this study, a set of 6 specific primers were designed according to the nuc gene (GenBank No. DQ507379.1) of S. aureus, and LAMP technique for S. aureus was established by optimizing the reaction conditions, and then the specificity, sensitivity and clinical detection effect of the method were evaluated. The results showed that the established method could specifically detect S. aureus, the minimum detect limit was 2.7×10¹ copies/μL, and the sensitivity of LAMP detection was 100 times higher than that of PCR method. The LAMP method which had the advantage of simplicity, rapidity, sensitivity and high specificity, was suitable to rapidly detect S. aureus in dairy farms. This study provides a technical reference for the early diagnosis of dairy cow mastitis caused by other pathogenic bacteria.