Chlorate resistance is one of the reliable characters to evaluate crop nitrogen efficiency. To identify QTL and candidate genes for chlorate resistance in maize (Zea mays), the narutal variation of 7 traits were evaluated under control and chlorate treatment in 283 inbred lines. Chlorate resistance was calculated for each traits. The results showed that chlorophyll relative content, plant height, leaf length and shoot dry weight were significantly reduced after chlorate treatment. A total of 133 SNPs were identified by genome-wide association analysis, and 51, 53 and 29 SNPs were identified under normal condition, chlorate treatment and chlorate resistance for each trait. In combined genome wide association study (GWAS) and RNA-seq 13, possible candidate genes were identfied, including cleavage and polyadenylation specificity factor, N-acetylserotonin O-methyltransferase and MYB transcription factor. These results provide candidate genes for understanding the genetic mechanism of chlorate resistance in maize, and could help to identify key gene of nitrogen use efficiency and improve of nitrogen use efficiency in maize.

In previous research of our research group, a cotton (Gossypium) fiber strength candidate gene Gh_D09G1210 was identified by combining transcriptome sequencing and QTL mapping, which belongs to homeodomain-leucine zipper (HD-ZIP)__N gene family. The purpose of this study was to identify HD-ZIP_N gene family members in G. hirsutum and analyze their role in the formation of cotton fiber strength. Genome-wide analysis of HD-ZIP_N gene family in G. hirsutum was carried out, and the differential expression patterns of HD-ZIP_N genes in cotton fibers at different days post anthesis were analyzed by real-time quantitative PCR (qPCR). A total of 18 genes of the HD-ZIP_N gene family were identified in G. hirsutum genome conserved motif analysis and gene-promoter analysis showed that the gene family members had highly similar gene sequences and structural domains. The phylogenetic tree showed that all the gene family members could be divided into 3 subcategories. According to the gene location, HD-ZIP_N genes were located on 10 chromosomes in G. hirsutum genome. Most of the homologous genes had been purified and selected according to the Ka/Ks results. Collinearity analysis showed that the members of the HD-ZIP_N gene family distributed on homologous chromosomes had a strong connection. Cotton fibers of 17 and 21 d post-anthesis (dpa) were used to carry out qPCR verification experiments. The results showed that 3 genes Gh_D11G0809, Gh_D04G0859 and Gh_A11G0693 had a significant down-regulation trend in 'PD94042' with average fiber quality and 'IL9' with elite fiber quality (P<0.05), while Gh_A09G1204 had a significant up-regulation trend in 'IL9' (P<0.05), indicating that HD-ZIP_N gene family members had effects on regulation of fiber strength development. The findings of this study suggest that the HD-ZIP_N gene family members participate in regulating the development of G. hirsutum fiber strength, and provide genetic resources for improving cotton fiber strength through molecular breeding.

The shift of soil microbial community is one of the main factors affecting continuous cropping. It has been observed that continuous cropping obstacles exist in celery (Apium graveolens) cultivation. However, the effects of continuous cropping of celery on rhizosphere soil microbial community remain unclear. In this study, Illumina MiSeq was used to study the shift of bacterial and fungal communities in the rhizosphere of celery after continuous cropping. The results showed that after continuous monoculture, the rhizosphere soil bacteria richness increased but the diversity did not change significantly, while the abundance and diversity of fungi decreased significantly. Taxonomic analysis further showed that Proteobacteria, Actinobacteriota, Acidobacteriota and Chloroflexi were the dominant phyla in all the sample bacterial communities, while Ascomycota was the absolute dominant phyla. After continuous cropping, the rhizosphere soil fungal community richness of diseased plants decreased significantly compared with that of healthy plants (P<0.05), decreased significantly compared with the soil without celery planting (P<0.01). In addition, LEfSe (linear discriminant analysis effect size) analysis results showed that the beneficial bacteria genera were significantly enriched in the healthy, diseased and uncultivated soils samples of the same field. Meanwhile, the significant increase (P<0.05) of the abundance of pathogenic fungus Stemphylium sp. in the rhizosphere of diseased plants indicated that the fungus might be an important factor causing continuous cropping disorder of celery. This study revealed the shift of bacterial and fungal community diversity and composition in celery rhizosphere soil under continuous cropping, which would be helpful to understand the microecological environment of celery rhizosphere soil under continuous cropping.

Pathogenesis-related protein 1 (PR1) gene plays an important role in plant resistance to biotic and abiotic stresses. Based on the transcriptome data of Ralstonia solanacearum stress previously conducted by our research group, in this study, a PR1 gene, named SlPR1b (Solyc00g174340.2) was cloned from tomato (Solanum lycopersicum) by reverse transcription PCR (RT PCR) technology. qPCR was used to reveal SlPR1b gene tissue expression specificity and expression characteristic under the conditions including infection with Ralstonia solanacearum, and treatment with salicylic acid (SA) and methyl jasmonate acid (MeJA). SlPR1b gene virus induced gene silencing (VIGS) vector was constructed and then transformed into tomato resistance material to analyze the resistance ability of SlPR1b gene silenced tomato in R. solanacearum stress condition. The results showed that the full-length cDNA sequence of SlPR1b gene was 807 bp, its ORF was 480 bp, encoding 159 amino acids, including a conserved CAP-PR-1 domain (cd05381), belonging to the CAP superfamily. The predicted molecular weight of SlPR1b was 17 519.73 D, the isoelectric point was 8.86, and the protein was found to be a secreted protein with a transmembrane structure. Homologous sequence alignment and phylogenetic analysis indicated that SlPR1b was highly homologous with a S. pennellii SpPR4 protein, followed by S. tuberosum StPR1b protein. The results of tissue specific expression showed that SlPR1b gene expression level was the highest in tomato leaves. Furthermore, SlPR1b gene expression could be induced by R. solanacearum, SA, and MeJA. Silencing SlPR1b decreased plant resistance to bacterial wilt, these results suggested that SlPR1b played a positive role in tomato resistance to bacterial wilt. This study provided a reference for further exploring the role of SlPR1b gene in the response of tomato to bacterial wilt.

Grapes (Vitis vinfera) are one of the four major fruits in the world, and their excellent cultivation depends to a large extent on grafting, which not only improves the resistance of the fruit trees, but also influences the fruit quality. The objective of this study was to investigate the effects of different rootstocks on the fruit quality and the expression of gluconeogenesis related genes in 'Shine Muscat' grapes, and to screen out rootstock combinations with excellent overall quality in Jiangsu and Zhejiang regions. In this study, samples of 'Shine Muscat' grapes grafted on 12 rootstocks were used to determine various quality indicators and to analyze the expression of phosphoenolpyruvate carboxykinase (PEPCK), pyruvate phosphate dikinase (PPDK), fructose-1,6-bisphosphatase (FBP) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes by real-time fluorescence quantitative PCR. The results showed that grafting of 12 rootstocks affected the quality index of 'Shine Muscat' grapes to varying degrees, especially the content of amino acids and sugar-acid fractions. Among the 12 rootstock combinations, '8B' rootstock grafted on 'Shine Muscat' gave the largest fruit size and hardness, '1103P' and '5BB' rootstocks grafted on 'Shine Muscat' gave the largest fruit solid-acid ratio, and 'Beda' rootstock grafted on 'Shine Muscat' gave the highest content of various amino acids in the fruit; '101-14' and '5BB' rootstocks had the highest glucose and fructose contents in the fruit after grafting 'Shine Muscat', while '3309C' rootstock grafted 'Shine Muscat' had the lower glucose and fructose contents in the fruit among the 12 rootstock combinations, but the content of acids such as tartaric acid, malic acid and citric acid was higher. Rootstock grafting had an effect on the expression of sugar anabolism-related genes, but it had the greatest effect on the expression of PEPCK gene, and the expression levels of PEPCK, PPDK, FBP and GAPDH were the highest in fruits of 'Shine Muscat' grafted on '101-14' rootstock. The expression of PEPCK genes in different rootstock combinations was significantly and positively correlated with glucose and fructose content, and it was hypothesized that different rootstocks affect the regulation of PEPCK gene in grape flesh, thus affecting conversion of organic acids to sugars and eventually the sugar accumulation. The top 3 rootstock combinations ranked in order by principal component analysis were 8B/SM, Beda/SM, and K3/SM. This study provides a theoretical basis for quality rootstock selection.

CBF (C-repeat binding factor) is a key transcription factor that can be rapidly induced and plays an important role in the response of plants to chilling stress. In this study, bioinformatics analysis of the common bean (Phaseolus vulgaris) CBF gene family and the expression of common bean CBF genes under chilling stress were examined using transcriptome data (RNA-seq) and qRT-PCR. The results showed that a total of 7 PvCBFs were identified in common bean, unevenly distributed on 5 chromosomes; phylogenetic analysis revealed that common bean CBF members were classified into 4 subgroups (Ⅰ~Ⅳ), which were identical to the results of gene structure and conserved motif analysis; covariance analysis revealed that there were 5 pairs of CBF gene families between common bean and Arabidopsis thaliana. The promoter analysis revealed that PvCBFs contained a variety of cis-elements involved in plant growth and development, hormone and stress response. The qRT-PCR results showed that 3 PvCBFs were significantly up-regulated under chilling stress (P<0.05). This study can provide a reference for subsequent study of the chilling tolerance function of PvCBF genes.

As a unique transcriptional regulator of terrestrial plants, NAC transcription factors play an active role in plant adaptation to environment and stress resistance. In this study, a total of 74 NAC transcription factors unevenly distributed on 10 chromosomes were identified in the whole genome of castor (Ricinus communis) by bioinformatics methods, and 13 intergenic replications occurred. Phylogenetic analysis showed that RcNACs and Arabidopsis?thaliana NACs were divided into 8 subclusters, and each subcluster contained a NAM domain and a conserved motif 2, and the gene composition structure was similar. A total of 15 stress-related, hormone-responsive and growth-related promoter elements were identified in the promoter region of RcNACs. The tissue expression profile showed that the 54 RcNACs detected had obvious tissue expression specificity in castor, and 39.8% of the members were highly expressed in the male flowers of castor. The stress expression profile showed that 47.3% and 49.1% of the 61 RcNACs were up-regulated in the early stage of salt and drought stress, respectively, except for 6 genes that did not respond to drought stress and salt stress; the low-temperature expression profile showed that 64.1% of the 39 RcNACs were up-regulated in the early stage of stress. The results of qRT-RCR detection under low-temperature stress showed that 10 RcNACs responded to low-temperature for a long time, and most genes had bimodal expression patterns and peaked at 72 h, indicating that RcNACs were the response genes of castor under stress. This study can provide a theoretical reference for the regulation of RcNACs in castor abiotic stress.

Cytochrome P450c17 (CYP17A1 ) is a rate-limiting enzyme in the pathway of cholesterol synthesis and plays a key role in androgen biosynthesis. It is of great significance to clarify the effect of CYP17A1 on testosterone synthesis and testicular development in goats (Capra hircus) for improving the fertility of rams. In this study, RNA interference vector of CYP17A1 was constructed and transfected into Leydig cells of Qianbei Ma goat. The knockdown effect of CYP17A1 gene was detected by qRT-PCR and Western blot. The effect of CYP17A1 knockdown on the proliferation of Leydig cells was detected by CCK-8 (Cell Counting Kit-8). The expression levels of proliferation-related genes, testosterone synthesis-related genes and testicular development-related genes were detected by qRT-PCR. The results showed that CYP17A1 was expressed in the testis and epididymis of each month old, and its gene knockdown effect was obvious, in which the expression of CYP17A1 gene and protein was significantly down-regulated (P<0.01), and the proliferation of Leydig cells was significantly inhibited (P<0.01). CYP17A1 gene knockdown significantly down-regulated the expression of proliferating cell nuclear antigen (PCNA) and cyclin E, CYP11A1, 3β-hydroxysteroid dehydrogenase type 1 (HSD3B1), HSD17B3 and CYP19A1, deleted in azoospermia like (DAZL) and insulin like growth factor 2 (IGF2)(P<0.01). This study provides basic data for further exploring the effect of CYP17A1 gene on the reproductive traits of Qianbei Ma goat.

Osteoprotegerin (OPG) plays a key role during bone development and dynamic homeostasis. The aim of this study was to explore the correlation between changes in peripheral blood OPG levels and antler osteogenesis in sika deer (Cervus nippon), and the possible mechanisms of OPG in the osteogenesis of antler reserve mesenchyme cells (RMCs). Enzyme linked immunosorbent assay (ELISA) and immunohistochemistry were used to detect the changes of OPG levels in the peripheral blood and antler tips of sika deer, and the expression levels of OPG in the osteogenesis of RMCs were detected by osteogenesis induction of antler RMCs using qRT-PCR and Western blot methods. The results showed that the OPG level in the peripheral blood of RMCs increased from May, peaked in August, reached the lowest level in December, and was maintained until May of the following year. OPG protein was expressed in the cell membrane and cytoplasm of RMCs, and increased from top to bottom in the antler tip and was widely expressed in the vascular wall and around the bone lumen. Alkaline phosphatase activity in RMCs started to increase from the 3^rd day after the addition of osteogenic induction solution, By 21 d of induction, RMCs were induced into osteoblasts with red-stained calcium nodules. The expression levels of RUNX family transcription factor 2 (RUNX2), Sp7 transcription factor (SP7), secreted protein acidic and rich in cysteine (SPARC), Biglycan (BGN) and TNF receptor superfamily member 11a (RANK) genes were significantly up-regulated during osteogenesis induction (P<0.05), and the OPG/RANKL (TNF superfamily member 11) ratio was reversed. the OPG protein level showed an increasing trend during osteogenesis. In conclusion, OPG levels in peripheral blood of sika deer were positively correlated with the osteogenesis process of antler, and OPG proteins expressed in antler tip might promote osteogenesis by regulating the differentiation of RMCs through the reversal of OPG/RANKL ratio. This study provides new insights into the osteogenesis of deer antler and new ideas for the treatment of osteoporosis in human (Homo sapiens).

Ribophorin Ⅱ (RⅡ) is a crucial subunit of the oligosaccharide transferase, and studies have shown that RⅡ is associated with cancer occurrence in humans (Homo sapiens), but there is currently limited research on the function of RⅡ in insects. In this study, a gene encoding RⅡ was identified in the brown planthopper (Nilaparvata lugens, BPH), a rice (Oryza sativa) pest, and is named N. lugens ribophorin Ⅱ (NlRⅡ)(GenBank No. XP_022202517.1). To investigate the function of NlRⅡ in BPH, the temporal expression pattern of NlRⅡ using transcriptomic data was first obtained, and the result revealed the expression pattern of NlRⅡ changed periodically with molting and reached a peak in each mid-instar stage. Then, qRT-PCR was used to detect the tissue-specific expression of NlRⅡ, the result showed that the expression level of NlRⅡ was highest in the ovary. Finally, RNA interference (RNAi) technique was used to silence NlRⅡ in the 2nd instar nymphs, and no significant effect was found on the survival of BPH. However, silencing NlRⅡ in the 5th instar resulted in female adult abdominal swelling, malformed ovary development, and almost no egg production. Additionally, significant decreases in egg number and hatchability were observed in wild-type female adults mated with male adults with extremely significantly constricted vas deferens (P<0.01). This study indicated that NlRⅡ could affect the reproduction of BPH, and provide a potential new target gene for RNAi-based BPH control.

Calcium plays an important role in the molting pathway in crustaceans, and it is also an essential element for crustaceans in the biomineralization of the new epidermis in the late ecdystic period. To investigate the effects of exogenous calcium supplementation in water on molting of Macrobrachium rosenbergii, this study conducted the culture experiment with the Ca²⁺ concentration of 25 (control group), 85, 145 and 205 mg/L in the water. At the end of the culture experiment, the molting rate of the 4 groups was calculated. The content of Ca²⁺ in the hemolymph was detected, and the effects of exogenous calcium supplementation on calcium absorption and exoskeleton mineralization were investigated using scanning electron microscopy. Meanwhile, the CDS of calmodulin (MrCaM, GenBank No. OQ411017) and calreticulin (MrCRT, GenBank No. OQ411018) in the molting pathway of M. rosenbergii were obtained. The expression levels of MrCaM and MrCRT mRNA in different molting stages of M. rosenbergii were analyzed by qPCR. The results showed that the molting rate of M. rosenbergii was the highest in the 145 mg/L group, and that in 205 mg/L group was significantly lower than that in 25 mg/L group (control group)(P<0.05). In the different molting stages, calcium content in hemolymph of M. rosenbergii firstly increased and then decreased with the increase of water Ca²⁺ concentration, reaching the peak in the 145 mg/L group. Scanning electron microscope (SEM) results showed that exogenous calcium supplementation could promote the exoskeletal mineralization. The expression levels of MrCaM and MrCRT at different molting stages were the highest in the 145 mg/L group (P<0.05) and significantly lower in 205 mg/L group compared to the 145 mg/L group (P<0.05). The correlation analysis of MrCaM and MrCRT with hemolymph calcium ion content in the different molting stages showed that the expression levels of MrCaM were significantly correlated with hemolymph calcium ion content in molting stage (E stage)(r=0.8854), and the expression level of MrCRT was positively correlated with hemolymph calcium ion content in the different molting stages (P<0.01). Overall, the increase of Ca²⁺ concentration in water could promote the molting and exoskeleton mineralization of M. rosenbergii. This study provides a basis for clarifying the effects of exogenous calcium supplementation on molting in M. rosenbergii.

Porcine circovirus type 2d (PCV2d) is a main subtype of PCV. It is an important pathogen causing multiple system failure syndrome of weaned piglets (Sus scrofa) and other pig immunosuppressation-related diseases, which seriously endangers the healthy development of China's pig industry. At present, the neutralizing epitopes of PCV2d reported are all located in the Cap protein, which is the key protein to produce neutralizing antibody. Neutralizing antibody can bind to the surface antigen of PCV2d to prevent virus infection. In this study, PCV2d Cap recombinant protein was expressed and purified by prokaryotic expression, and then immunized BALB/c mice (Mus musculus). Two hybridoma cell lines (IB3, IB4) with murine monoclonal antibodies against PCV2d Cap protein were screened, among which 1B3 had neutralizing activity and no cross-reaction with other viruses. After chimeric 1B3 antibody variable region gene and porcine constant region gene were cloned into the eukaryotic expression vector, a stable expression cell line of PCV2d Cap recombinant porcine chimeric antibody r1B3swine was prepared by Chinese hamster (Cricetulus griseus) ovarian CHO-S cells. Neutralization test and Western blot results showed that r1B3swine combined well with PCV2d virus and did not cross-react with the murine secondary antibody. In conclusion, the eukaryotic expression system of pig-derived monoclonal antibody r1B3swine against PCV2d Cap protein constructed in this study provides a material basis for the study of the structure and function of PCV2d Cap protein and the development of a new therapeutic and diagnostic formulation for PCV2.

Citrus Huanglongbing (HLB) is one of the most devastating diseases in citrus industry, mainly caused by phloem-limited Candidatus Liberibacter asiaticus (CLas). SDE34 (CLIBASIA_04055) is one of the core sec-dependent effectors (SDEs) from CLas. In order to screen the host target of SDE34 during CLas infection, a yeast two-hybrid (Y2H) cDNA library was constructed using CLas infected Newhall navel oranges (Citrus sinensis) leaves and screened with SDE34 as a bait. The titer of the yeast two-hybrid library was 2.3×10⁸ CFU/mL, and the length of the insert fragments ranges from 300 to 2 000 bp. Three citrus proteins interacting with SDE34 were identified, among which the screening frequency of heavy metal-associated isoprenylated plant protein (HIPP7) was 83.33%. Followed bimolecular fluorescence complementation (BiFC) assay confirmed that HIPP7 interacted with SDE34 in plant cells. Subcellular localization showed that HIPP7-GFP fusion protein localized in cytoplasm and nucleus in plant cells. And the expression level of HIPP7 was very significantly down-regulated (P<0.001) after CLas infection indicated by real-time quantitative PCR assay. HIPP7 homologous genes function as susceptibility factors in various plant-pathogen interaction systems, suggesting that SDE34 might promote CLas infection by targeting the citrus susceptibility gene HIPP7. This study provides a theoretical basis for analysis of the pathogenesis of CLas and citrus disease resistance breeding.

Gastrodia elata is a traditional Chinese medicinal herb that can be used for both medicine and food. G. elata has no roots or leaves, and can only obtain nutrients through the digestion of infected Armillaria mellea. Nitrogen nutrition is essential for the growth of G. elata and A.mellea, and glutamine synthetase (GS) plays an important role in regulating nitrogen metabolism. Previous studies have shown that overexpression of the cytoplasmic GS1 gene can improve plant nitrogen utilization, plant development, and salt stress tolerance, but the resistance of the GS1 gene to low temperature stress is still unclear. In this study, the 5' CDS of GS1 gene was screened from the transcriptome database of G. elata, and it's full length was cloned by Nested-PCR. The overexpression vector pH2GW7.0-35s-GS1 and prokaryotic expression vector pET-32a-GS1 were constructed. pET-32a-GS1 was transformed into Escherichia coli Bl21 for protein express and purification to obtain GS1 enzyme protein. The optimal pH of GS1 enzyme was 4 and the optimal temperature was 50 ℃. Under low concentration of 5 mmol/L Ca²⁺, Mg²⁺ and K⁺ had a promoting effect on GS1 enzyme activity. While at high concentration of 9 mmol/L metal ions had a inhibitory effect on GS1 enzyme activity. Compared with wild A. mellea, overexpression of GS1 significantly enhanced the expression levels of GS, glutamate synthase (GoGAT), glutamate dehydrogenase (GDH), glutathione reductase (GR) and glutathione peroxidase (GPX) genes related to glutamate and glutathione synthesis under low temperature conditions of 13 ℃, increased the content of proline, glutathione and soluble sugar, and reduced the content of H₂O₂ and malondialdehyde (MDA), significantly promoted the growth of A. mellea. These results indicated that overexpression of G. elata GS1 gene could enhance the growth ability of A. mellea under low temperature conditions. This study provids a reference for further research on enhancing growth and yield of G. elata under low temperature.

Baijiu Daqu contains rich microorganisms. Among them, Bacillus amyloliquefaciens can inhibit plant pathogens, be used in biological control, promote plant growth, and have potential application value in agricultural production. In this study, LB medium was used to isolate the B. amyloliquefaciens from Beidacang Baijiu Daqu, and the strain were identified by the morphology and molecular biology such as colony, cell observation, spore staining, 16S rRNA gene sequencing and comparison techniques. This bacterium was the most similar to Bacillus amyloliquefaciens (GenBank No. MG593943.1) with 100% consistency and 95% coverage. It belonged to B. amyloliquefaciens and was named as M1-1 strain. It was submitted to the NCBI website and obtained the GenBank No. OM321552. The inhibitory effects of B. amyloliquefaciens M1-1 antibacterial protein on 4 plant pathogenic fungi, namely Fusarium oxysporum M1, Phacidiopycnis washingtonensis, Gibberella and Rhizoctonia solani, were studied by plate confrontation and Oxford cup methods, respectively. The fermentation broth of B. amyloliquefaciens M1-1 had strong antibacterial effects on all 4 plant pathogens mentioned above, with a antifungal rate ranging from 43% to 61%; In addition to producing protease, B. amyloliquefaciens M1-1 could also produce a variety of antifungal proteins, and the diameter of the inhibitory ring was between 1.8 and 3.0 cm; The pot experiment method was used to study the promoting effect of B. amyloliquefaciens M1-1 on the growth of Bryophyllum pinnatum. The experimental results showed that B. amyloliquefaciens M1-1 had a significant promoting effect on the growth of plants. In summary, this B. amyloliquefaciens M1-1 has good inhibitory effects on various plant pathogens and could be applied to the development and utilization of biocontrol agents, and it also has potential application value in increasing crop yield.

The omics-related research currently holds a prominent position in fruit tree studies. Collaborative investigations encompassing genomics, transcriptomics, proteomics, metabolomics, and so forth can enhance the efficiency of studies on various aspects of fruit trees. This includes exploring the origin and domestication history, understanding the mechanisms behind the formation of importantly economical traits, and identifying genes and molecular markers essential for molecular breeding practices and the molecular regulation of growth and development. The jujube (Ziziphus jujuba) is a native fruit tree that originated and was domesticated in China, and it is one of the fruit trees subjected to early whole-genome de novo sequencing. Its genome was sequenced in 2014, and since then, intensive studies through the way of multi-omics have been performed, leading to a new era in jujube research. This article systematically summarizes recent advancements in jujube genomics, transcriptomics, and metabolomics. Additionally, it outlines prospective avenues for multi-omics investigations of jujube. These insights collectively contribute to the future trajectory of jujube research, particularly in the realms of breeding and understanding the mechanisms controlling the formation of critical traits in jujube.

Southern rice black-streaked dwarf disease is a important rice (Oryza sativa) virus disease in Asian that caused by the Southern rice black-streaked dwarf virus (SRBSDV). SRBSDV transmitted by a typical long-distance migratory vector insect, white-backed planthopper (WBPH) (Sogatella furcifera), is currently endemic in rice producing areas in southern China, and severely reduces rice yields. So far, studies on the genome organization and function, epidemiological history and transmission rule of SRBSDV, as well as its interaction mechanism with rice and WBPH have made some breakthroughs. This review summarized the symptoms, geographical distribution, genome structure and function of SRBSDV, focused on the biological process of the transmission of SRBSDV by WBPH, and the interactions between SRBSDV and WBPH.Then possible orientations for further research on this disease were suggested. This review provides guidelines for subsequent research and control of this virus and other viruses from the same family.

Porcine mammary epithelial cells (PMECs) are highly differentiated in vitro and can maintain their unique morphological characteristics and function of producing and secreting milk proteins. Therefore, it is of great significance to establish a stable immortable PMECs line that can maintain the characteristics of PMECs for the study of the development, differentiation and lactation mechanism of porcine mammary gland. In this study, tissue block culture method and enzymatic digestion method were used to isolate and purify mammary epithelial cells from sows (Sus scrofa) at the end of pregnancy, and the cell culture method was optimized. Human telomerase reverse transcriptase (hTERT) gene was transfected into primary cultured pig mammary epithelial cells, by PCR detection, the immortalized hTERT-PMECs was obtained. The morphological observation of hTERT-PMECs cultured continuously for 60 generations showed that the type of hTERT-PMECs cells did not change after immortalization. The results of immunofluorescence staining showed that hTERT-PMECs could express keratin. After the induction of prolactin, hydrocortisone and Insulin-Transferrin-Selenium (ITS), hTERT-PMECs was identified by reverse transcription-PCR (RT-PCR), the result showed that hTERT-PMECs still had the function of secreting lactoprotein. In summary, this study successfully obtained the immortalized porcine mammary epithelial cell line hTERT-PMECs, and the immortalized cells maintained the same characteristics as the primary cells. This study provides basic data for the study of mammary gland development and lactation.

Chrysanthemums morifolium are mostly hexaploid, with complex genetic backgrounds and low efficiency in stable genetic transformation. This study aimed to optimize the transient expression system in C. morifolium and improved the transient transformation efficiency as well as target gene expression activit, to provide an effective way to carry out functional studies of Chrysanthemum-related genes. C. morifolium 'Jinba' cuttings were transient transformed by using the vacuum infiltration method, and the infiltration efficiency was statistically analyzed by 6 aspects: Type of suspensions, pH of suspensions, whether to add acetosyringone, final concentration of Agrobacterium suspension, dark incubation time of Agrobacterium and dark incubation temperature of plants. And the expression efficiency was determined by measuring and analyzing the expression of fluorescence values of luciferase (LUC) to explore the influence degree of 6 conditions on the transient transformation efficiency and target gene expression activity of C. morifolium. The experimental results showed that 2-morpholinoethanesulphonic acid (MES) buffer was more suitable as suspension when infiltrating chrysanthemum, and the highest level of fluorescence expression was obtained when the pH of suspension was 6.0; next, the addition of acetosyringone (100 μmol/L) could improve the transformation efficiency of transient infection and the expression level of fluorescence value; the expression of fluorescence increased significantly when the final OD₆₀₀ value of suspension was 1.8; the expression of fluorescence value was more favorable when the suspension was placed in dark culture at 28 ℃ for 4 h. In addition, the efficiency and the expression of fluorescence value were increased when the plants were cultured in the low temperature condition (at 10 ℃). This study significantly improved the expression of fluorescence value of C. morifolium and achieved effective transient expression in a short experimental period by changing the conditions of the composition of the suspension, the concentration of the suspension, the suspension, and the culture conditions of the plant after instantaneous transformation, which provides efficient method for the functional study of C. morifolium genes.

Toxoplasma gondii is a worldwide zoonotic parasite with a high chronic infection rate in pigs (Sus scrofa) and small ruminants. It can cause great harm to individuals after being infected with immunocompromised people through food-borne transmission. In this study, a set of specific primers were designed according to the 529 bp gene sequence of T. gondii (DQ779191.1) published in GenBank, and a semi-nested PCR real-time fluorescence method was established based on SYBR GreenⅠ dye to detect T. gondii. In the first-round of amplification, the 529 bp repetitive sequence of T.gondii was amplified by external primers, and then the 529 bp gene fragment was amplified by real-time fluorescence amplification with the internal primer of the second-round of amplification combined with SYBR GreenⅠ dye, and the final product fragment length was 260 bp. Under the optimized reaction conditions, the detection limit of this method was 18.4 fg/μL with high sensitivity. There was no cross reaction with the genomes of Echinococcus granulosus and Taenia solium, and the specificity was sound. Therefore, this study successfully established a new semi-nested PCR real-time fluorescence detection method with high sensitivity and specificity, which provides an effective technical means for monitoring T. gondii infection in livestock and meat products.

Prunus mume, one of the top 10 traditional famous flowers in China, is widely used in gardens. With the development of molecular biology research of P. mume, it is very important to screen reference genes suitable for qPCR analysis of flower color synthesis genes in P. mume. In this study, a total of 6 P. mume cultivars of 3 different color lines were selected for flower color phenotypic analysis and anthocyanin content determination, and it was found that anthocyanin content was positively correlated with the color of P. mume petals. Meanwhile, the expression of 14 candidate reference genes was detected among different color varieties of P. mume using qPCR, and their expression stability was analyzed using 3 software (including geNorm, NormFinder, BestKeeper) and ΔCt method. Finally, the best reference gene was synthesized using the RefFinder program and validated using genes related to anthocyanin synthesis. The experimental results showed that the expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and actin 1 (ACT1) were the most stable and ACT3 was the least stable. The validation results showed that when GAPDH and ACT1 were used as reference genes, the expression patterns of anthocyanin synthesis-related genes were similar, and more genes showed significant differential expression; when ACT3 was used as reference gene, the expression patterns of anthocyanin synthesis-related genes were different from the results of GAPDH and ACT1 as reference genes, and only a few genes showed significant differential expression. This study provides basic data for in-depth analysis of the expression patterns of genes related to flower color synthesis.