Sensor technology is the foundation of agricultural informatization, and it is one of the core elements and key support to realize agricultural modernization. First, this paper summarizes the current technical status and application of agricultural sensor technology in three areas of intelligent agricultural machinery equipment, agricultural unmanned aerial vehicle (UAV) based remote sensing, and agricultural internet of things, and conducts an in-depth analysis on the technical demands and market development of agricultural sensor in China. Second, the industrialization, marketization, and future development trends of agricultural sensors were summarized and pointed out through the technical industry analysis. Finally, 16 key technologies in the field of agricultural sensor industry were condensed, and on this basis, a Delphi-based expert questionnaire survey was carried out. The results showed that universality was the most important attribute of agricultural sensors; basic theory and research and development input were the two biggest constraints to the development of agricultural sensor technology. It was proposed that the agricultural sensor technology would develop towards low cost, high stability, high intelligence, portability, and operability in the future. This paper provides a reference for the technical and industrial development of agricultural sensors in China.
OsSPL transcription factor plays an important role in the development and stress response of rice (Oryza sativa) roots, leaves, floral organs, and ears. In this study, the OsSPL3 promoter was analyzed to explore the expression pattern of OsSPL3 transcription factor in rice and its response to drought stress. The Cis-acting elements in the OsSPL3 promoter region were analyzed by PLACE and Plant CARE online softwares, and the recombinant expression vector of OsSPL3 promoter and β-glucuronidase(GUS) gene was constructed, which was transformed into ZH11 rice callus, and positive transgenic plants were obtained by screening. The GUS expression activity of pOsSPL3-GUS transgenic plants and the expression patterns under drought stress and abscisic acid (ABA) treatments were detected. The results of promoter analysis showed that in addition to the necessary transcription initiation core elements and light-responsive elements, the OsSPL3 promoter region also included three MYB-involved drought-inducible elements, three gibberellin-responsive elements, two anaerobic induction essential elements, one low temperature response element, one endosperm expression regulatory element, one zein metabolism regulatory element and one meristem expression-related regulatory element. The results of GUS staining showed that the expression activity of GUS gene in young leaves, stem sheaths, coleoptiles and other young tissues was high, as well as in the vigorous growth parts of roots such as root cap, meristem zone, and elongation zone. In addition, the drought stress could significantly enhanced the GUS activity of transgenic rice leaves and roots. It shows that OsSPL3 transcription factor plays a regulatory role in the process of coleoptile growth, new leaf formation, root extension and stem sheath elongation after seed germination, and OsSPL3 transcription factor is also involved in the response process of rice drought stress.
Ralstonia solanacearum causes bacterial wilt disease in multiple crops, which severely threatens the global crop safety production. This pathogen exhibits high genetic diversity and evolves rapidly, and there is a lack of effective disease-resistant varieties in production, which brings great challenges for effective disease control. Identifying receptor proteins in plants that recognize associated molecular patterns or effectors of R. solanacearum and elucidating their molecular recognition mechanisms can provide clues to understand the mechanisms of plant-pathogen interaction, and lay a basis for the development of broad-spectrum disease resistance in plants. This paper reviewed the recent progress on the molecular basis of plant-R. solanacearum recognition. We mainly focused on the identification and functional analysis of membrane and intracellular receptors that recognize R. solanacearum in plants, as well as the mechanism behind receptor recognition of the associated molecular patterns or effectors from R. solanacearum. Besides, we provide research prospects for the exploration and utilization of disease-resistant resources against R. solanacearum in the future.
Cohesin is a functionally and evolutionarily conserved multi-subunit protein complex that is required for sister chromatid cohesion and chromatin loop structure in both mitosis and meiosis. The meiotic cell-cycle consisting of one DNA replication and two successive rounds of chromosome segregation completes the segregation of homologous chromosomes and sister chromatids. Cohesin is crucial for faithful and proper segregations. There is a group of distinctive cohesin subunits that are only expressed in meiotic cells. The study of meiosis-specific cohesin is of great significance for understanding chromosome architecture and dynamics in meiosis. REC8 is a typical meiosis-specific cohesin subunit that plays essential roles in sister chromatid cohesion and meiotic chromosome events. Here, we review the function and mechanism of meiotic cohesin REC8 based on the current study and hypothesize that phosphorylation modification and microRNAs (miRNAs) could be the subsequent research directions of REC8.
In order to explore the molecular mechanism of alkaloid biosynthesis in lotus leaves, metabolomics and transcriptomics sequencing analyses were performed on mature lotus leaves of ‘Taikong Lian’ (high alkaloid content), ‘Juwuba’ (medium alkaloid content) and ‘Dazu Honglian’ (low alkaloid content) cultivars with significant differences in alkaloid content. Metabolomics analysis showed that there were 30, 32 and 14 different metabolites in the three groups of ‘Dazu Honglian’ vs ‘Taikong Lian’ (low vs high alkaloid content), ‘Dazu Honglian’ vs ‘Juwuba’ (low vs medium alkaloid content), and ‘Taikong Lian’ vs ‘Juwuba’ (high vs medium alkaloid content), respectively. These differential metabolites were mainly three types of isoquinoline alkaloids, namely benzylisoquinoline, bis-benzylisoquinoline and aporphine alkaloids, specifically including caaverine, 3′-glucosyl-6, 7-dihydroxy-N-methyl-benzyltetrahydroisoquinoline, dopamine, L-tyramine, etc. To further explore the key genes of the above isoquinoline alkaloid biosynthesis pathway, the transcriptomics sequencing analysis of three cultivars were performed. The numbers of differentially expressed genes (DEGs) among the three groups (‘Dazu Honglian’ vs ‘Taikong Lian’, ‘Dazu Honglian’ vs ‘Juwuba’, and ‘Taikong Lian’ vs ‘Juwuba’) were 2 866, 2 739 and 3 932, respectively; and there were 379 DEGs in common, which contained isoquinoline alkaloid biosynthesis pathway genes. Combined with the results of metabolomics analysis, six key DEGs, including NnCYP80G, Nn6OMT, NnTYDC, NnNCS, NnRAV and NnERF, were finally screened and verified by real-time fluorescent quantitative polymerase chain reaction, which can be used for subsequent gene function verification and molecular regulation network analysis.
Ralstonia solanacearum is a very harmful plant pathogenic bacterium, and the plant bacterial wilt caused by it seriously affects the healthy production of tomato and potato crops. It has broad host varieties and can acquire new virulence through horizontal gene transfer and gene recombination to extend the host range. The pathogenic mechanism of R. solanacearum is complex, type Ⅲ secretion system (T3SS) is the key pathogenic factor, and the type Ⅲ effectors (T3Es) secreted by it play important roles in the pathogenic processand inhibit innate immune response of hosts at different levels. Moreover, plant hosts can recognize R. solanacearum effectors and activate effector-triggered immunity (ETI) to achieve disease resistance. In this review, the virulence and avirulence mechanisms of R. solanacearum T3Es were discussed and summarized, providing insights for further understanding the pathogenesis of R. solanacearum and the mechanisms of plant resistance to bacterial wilt.
In plants, target of rapamycin (TOR) functions as a pivotal signaling and metabolic hub, integrating nutrient availability, energy status, and environmental cues through phosphorylation. This regulatory mechanism plays a crucial role in governing plant growth, development, and environmental adaptation. In this paper, we provide a comprehensive review of the discovery and characterization of TOR in plants. We summarize previous and recent studies on the signaling pathway of plant TOR, highlighting the identification of upstream effect factors and downstream substrates. Additionally, we discuss the diverse roles of TOR in plant embryogenesis, meristem formation, nutrient utilization, flowering, senescence, and responses to both abiotic and biotic stresses. Furthermore, we explore the potential research prospects for TOR kinase and its application in agriculture.
Bacterial wilt, a typical vascular disease caused by Ralstonia solanacearum, is one of the most devastating diseases and dramatically reduces crop yield and quality. The most effective strategy for controlling wilt disease is breeding disease-resistant varieties, which requires understanding the molecular mechanisms underlying plant immune responses against R. solanacearum. However, more and more evidence suggests that vascular immune responses are cell type specific. After sensing of R. solanacearum, the cell wall lignification of vascular tissues plays a vital role in restricting the spread of R. solanacearum. Lignin biosynthesis pathway genes are strictly controlled at the transcriptional, translational, and spatial-temporal specific expression aspects. Here, we summarized the current understanding of the recognition and signal transductionupon R. solanacearum infection and the research progress of pathogen-induced vascular lignification on regulating resistance to R. solanacearum, including the expression of lignin biosynthesis genes, the transport and polymerization of monolignols, and the generation of different types of lignin. We hope that this review will provide a theoretical basis for breeding bacterial wilt disease-resistant cultivars by modifying vascular lignification.
Oil crop breeding programs generally aim to improve yield, quality, and stress resistance. Major oil crops include soybean, rape, sunflower and peanut according to their current production worldwide. This paper reviewed the molecular tools and technological innovation in oil crop breeding, including advanced technologies such as genome selection, genome editing, and molecular design breeding. Challenges exist in current genetic studies and breeding practices, and future perspectives of technological progress and application are also discussed for achieving high yield, high quality, and efficient breeding of oil crops.
In order to identify the pathogens causing tomato bacterial spot disease in Ningxia, tomato leaves infected with bacterial spot disease from Zhongwei and Wuzhong cities of Ningxia were used as the materials, and the strains were isolated using the conventional tissue isolation method, and their morphology, molecular biology and pathogenicity were identified. The four-factor and three-level orthogonal design of experiment [L9(34)] was conducted to screen the indoor resistance identification method at the seedling stage. The results showed that the colony morphologies of strain 1 isolated from Zhongwei City and strain 2 isolated from Wuzhong City were all milky white, full edge, opaque, smooth surface, producing green fluorescence, rod-shaped cells, and Gram staining was negative. The 16S rDNA sequences of both strain 1 and strain 2 were 99.93% similar to that of Pseudomonas syringae pv. tomato pathogenic variant KT783475.1. After reinoculation, brown lesions with yellow halos were presented on the leaves of the tomato, which was consistent with the natural symptoms. So, it was confirmed that the pathogen causing tomato bacterial spot disease in Ningxia was P. syringae pv. tomato. Under the treatment combination of inoculating seedlings at the four-leaf stage, the bacterial suspension concentration of 1.00×107 CFU/mL, with stem inoculation method and 96 h moisture, the disease index was 72.22%, which was significantly higher than that in other treatments, and thus it was considered to be the best indoor resistance identification method at the seedling stage for tomato bacterial spot disease. The above results will provide a theoretical basis for the prevention and control of tomato bacterial spot disease and resistance breeding in Ningxia.
To explore the regulation mechanism of TCP4 gene on the development of petal spur of Impatiens uliginosa, the full length cDNA of TCP4 gene in I. uliginosa (named as IuTCP4) was cloned by reverse transcription polymerase chain reaction, and its sequence was analyzed by bioinformatics. Then, real-time fluorescent quantitative polymerase chain reaction (qRT-PCR) was used to investigate the spatiotemporal expression pattern of IuTCP4 gene at different developmental stages and different tissue locations of petal spur. The results showed that the full-length cDNA of two copies (IuTCP4.1 and IuTCP4.2) of TCP4 gene in I. uliginosa were 1 194 bp and 1 173 bp, encoding 397 and 390 amino acids, respectively, and neither contained introns. Both of IuTCP4.1 and IuTCP4.2 encoded proteins were unstable and hydrophilic without signal peptide and transmembrane domain. The homology of amino acid sequences of TCP4 protein between I. uliginosa and other 15 species, such as tea (Camellia sinensis) and balsam pear (Momordica charantia), reached 66.11%. In the phylogenetic tree, IuTCP4.1 and IuTCP4.2 clustered into one branch, suggesting that the two copies of IuTCP4 are paralogous genes. The results of qRT-PCR showed that IuTCP4.1 was differentially expressed between petal spur and limb at both the early stage and blooming stage, with the highest expression quantity in the limb at the early stage; IuTCP4.2 was differentially expressed between petal spur and limb at all three developmental stages, and the highest expression quantity was observed in the petal spur at the early stage. In conclusion, IuTCP4 plays a certain regulatory role in the development of petal spur and mainly functions at the early stage of petal spur development. It is provided a theoretical basis for the development mechanism of petal spur, flower shape improvement and new variety cultivation of Impatiens.
In order to explore the pathogen of emulsification disease in Chinese mitten crab (Eriocheir sinensis) in Tianjin district, the epidemiological investigation, pathogen isolation, 18S rDNA gene sequence analysis, artificial infection test, and immunohistochemistry (IHC) analysis were carried out for identification of the pathogen, tissue distribution and temporal variation characteristics in this study. The results showed that the main clinical symptoms of naturally infected crabs included slow or almost no response to external stimuli, emulsify hemolymph accumulation in the cephalothorax cavity, opaque and whitish muscles at cephalothorax and joint membrane at the base of claw joints, and white semi-fluid emulsification of the hepatopancreas. The fungal strain P13, isolated from the diseased crab, was identified as Metschnikowia bicuspidata according to the phylogenetic analysis based on 18S rDNA gene sequences. Artificial infection test results showed that P13 could infect healthy Eriocheir sinensis under the laboratory condition, with cumulative mortality of (55.0±2.4)%, causing clinical symptoms similar to those found in the naturally infected crabs, and the Metschnikowia bicuspidata can be isolated from the experimental crabs again. IHC analysis results indicated that P13 infected various tissues of Eriocheir sinensis, including hepatopancreas, hindgut, gill, heart, and muscle, causing pathological damages in different degrees and temporal variation characteristics in the targeted tissues. In conclusion, Metschnikowia bicuspidata was the pathogen of the emulsification disease in Eriocheir sinensis. This study preliminarily revealed the main target tissues of Metschnikowia bicuspidata and the characteristics of tissue distribution and temporal variation, which provides a theoretical basis for clarifying the pathogenesis of Metschnikowia bicuspidata, and offers technical support for the control and prevention of emulsification disease in Eriocheir sinensis.
Under the iron-deficiency condition, roots of graminaceous plants secrete mugineic acids into the soil. To determine the effects of rice root exudate 2′-deoxymugineic acid (DMA) on rhizosphere and root endosphere bacterial community, wild type rice named as Nipponbare and osbhlh156 and iro2 mutant rices that loss the ability to secrete DMA were used as experimental materials in this study. The rhizosphere and root endosphere microorganisms were sampled for DNA extraction and 16S rRNA gene amplicon sequencing and data analysis. The results showed that soil types and cultivation conditions had significant impacts on rhizosphere and root endosphere bacterial community composition. In contrast, the root exudate DMA had relatively less impact, but not negligible. The bacterial species and diversity decreased from rhizosphere to root endosphere, which confirmed that the root endosphere bacteria were gradually selected and colonized inside root by interacting with plants. Nine microbial taxa, including Bradyrhizobium and Dictyobacter, etc., were selected as biomarkers, to distinguish whether there is DMA secretion in the rice rhizosphere. Through functional prediction, it was found that the bacterial taxa with adenosine triphosphate-binding cassette (ABC) transporter function may be involved in plant iron transport and related function. This study clarifies the effects of DMA on the composition of rhizosphere and root endosphere bacterial community of rice and provides data support for the comprehensive analysis of the role of microorganisms in response to iron deficiency in rice.
Polychlorinated biphenyls (PCBs) are typical pollutants in soil. Nanoscale zero-valent iron (nZVI) can effectively dechlorinate high-chlorinated PCBs into low-chlorinated PCBs which can be more easily degraded by microorganisms. In this study, soil samples contaminated by PCBs were collected from an e-waste recycling site in Taizhou, Zhejiang Province. The remediation of combined nZVI and PCBs-degrading strain Rhodococcus pyridinovorans R04 was carried out to investigate the removal effect of PCBs in soil. The results showed that the combined treatment of nZVI and degrading strain R04 had better effects than the treatment of nZVI or R04 alone in removing PCBs or various chlorinated PCB congeners in soil. After combined treatment with nZVI and degrading strain R04 for 32 d, the removal rate of PCBs in soil reached 59.4%, which was higher than 46.1% of nZVI treatment and 34.4% of degrading strain R04 treatment (P＜0.05). Therefore, the combination of nZVI and degrading bacteria in the remediation of PCBs contaminated soil has good application potential.
Krait software was used to analyze the distribution characteristics of perfect microsatellites in the whole genome of Protosalanx chinensis, which was published in 2020 with a higher degree of splicing, and to develop polymorphic microsatellite DNA (also known as simple sequence repeat) markers. The results showed that a total of 587 554 perfect microsatellite loci were obtained in the whole genome of P. chinensis, with a total sequence length of 11 803 017 bp, accounting for 2.53% of the whole genome length. Among six repeat types of microsatellites, the number of dinucleotide was the largest (401 585, accounting for 68.35%). In the 99 pairs of primers designed for microsatellite loci， 39 were polymorphic. Among them, 14 microsatellite markers with favorable polymorphism were selected to test one representative population selected from each of the migratory, landlocked, and introduced populations. The results indicated that 14 microsatellite markers with favorable polymorphism could achieve effective amplification in the three representative populations. The genetic diversity and genetic structure of the three populations were analyzed, and it was found that the migratory population (Chongming Island population) had abundant genetic variation (the mean expected heterozygosity is 0.614, and the mean polymorphism information content is 0.576), which could be clustered into a genetic group different from the freshwater populations [including Taihu Lake population (landlocked) and Lianhuan Lake population (introduced)], and there were large genetic distance and extremely high level of genetic differentiation level between them [the genetic differentiation index (Fst) is higher than 0.25, P＜0.05]. The genetic variations between the two freshwater populations (Taihu Lake and Lianhuan Lake populations) were relatively scarce and the genetic distance between them was small. Although there was significant genetic differentiation between them, the genetic differentiation level was relatively low (Fst=0.102, P＜0.05). These results indicate that the migratory population has potential conservation value of germplasm resource, which provide basis for the development of microsatellite markers and construction of genetic maps, and furthermore provide references for the subsequent evaluation of large-scale population germplasm resources of P. chinensis.
To prepare the specific antibodies against nucleocapsid (N) protein of feline coronavirus (FCoV), the full-length cDNA of N gene was amplified from type ⅠFCoV (ZJU1709) and subcloned into pCold TF prokaryotic expression vector. The recombinant N protein was induced by isopropyl-β-D-thiogalactopyranoside (IPTG) at low temperature and affinity-purified using nickel column. The rabbit polyclonal antiserum was prepared using the purified recombinant N protein as antigen. Finally, the enzyme-linked immunosorbent assay (ELISA), Western blotting (WB) and indirect immunofluorescence assay (IFA) were applied to identify the reactivity of rabbit polyclonal antiserum. The results showed that the soluble recombinant N protein with a molecular weight of about 100 kDa was successfully induced and further purified under non-denaturing condition at a concentration of 1.4 mg/mL. The ELISA titer of the prepared rabbit polyclonal antiserum of N protein can reach 1×106, and it can react with the recombinant Flag-N eukaryotic protein and N protein in FCoV-infected cells by WB and IFA. Cross-reactivity analysis showed that the polyclonal antibody can react with N proteins of alphacoronavirus, including various subtypes of FCoV, as well as canine coronavirus (CCoV), porcine transmissible gastroenteritis virus (TGEV), and porcine epidemic diarrhea virus (PEDV), but failed to react with N proteins of betacoronavirus of severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) and gammacoronavirus of infectious bronchitis virus (IBV). In summary, the soluble recombinant N protein expressed by using pCold TF prokaryotic system showed strong immunogenicity. The rabbit polyclonal antiserum against N protein of FCoV can recognize N proteins of multiple species from alphacoronavirus, but showed no cross-reactivity with N proteins of betacoronavirus and gammacoronavirus. This antibody facilitates to study the replication mechanism of FCoV and develop efficient methods for antigen or antibody detection.
Influenza is an important zoonotic disease. The highly pathogenic avian influenza not only brings enormous losses to China’s livestock breeding industry but also seriously threatens the safety of public health. The ability of influenza viruses to recombine in swine and spread across species barriers poses significant challenges for influenza prevention. Due to the rapid mutation of influenza viruses, the differences between prevalent viruses and vaccine strains reduce the vaccine efficacy. It is necessary to improve the host’s immunity to influenza viruses. Probiotics regulate the balance of intestinal microbiota and promote body health, which is beneficial for protecting animal against influenza viruses. This paper reviewed the mechanisms of anti-influenza virus action of probiotics in animals. The mechanisms include direct or indirect interference with virus attacks by balancing the composition of intestinal flora, regulating the mucosal barrier function of body, and enhancing or suppressing Toll-like receptor-related molecular signaling pathways. This study provides scientific evidence for understanding the mechanisms by which different strains of probiotics combat influenza and for developing more effective anti-influenza strategies.
The existing traditional active preservation packaging has disadvantages such as low porosity and poor air permeability, so the fabrication of nano-scale packaging materials that can release slowly and retain freshness is a hot research topic in the field of storage and logistics of postharvest fruits and vegetables. In this study, polycaprolactone (PCL) nanofiber membranes loaded by thymol (THY) were prepared by the solution blow spinning technique, and the properties of THY/PCL nanofiber membranes were evaluated by material characterization and bacterial inhibition experiments. The results showed that the THY/PCL nanofiber membranes had lower crystallinity and increased thermal stability, while their water vapor permeable properties, surface hydrophobicity, and mechanical properties were not affected. In addition, the THY/PCL nanofiber membranes showed good antibacterial activity against Escherichia coli and Staphylococcus aureus, demonstrating a good application prospect in the field of postharvest preservation of fruits and vegetables.
Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (Cas) (CRISPR/Cas) system, an ancient bacterial and archaeal immune system, has rapidly developed into a popular gene-editing tool, which largely promotes the development of several biology-related fields. By combining the CRISPR/Cas systems with the isothermal amplification techniques, the novel and effective detection methods with high sensitivity and independence of equipment have been established, such as DNA endonuclease-targeted CRISPR trans-reporter (DETECTR) and specific high-sensitivity enzymatic reporter unlocking (SHERLOCK). These new technologies not only improve the performance of the CRISPR/Cas system in different situations, but also inspire its application potential in the on-site detection. In this review, we summarized the nucleic acid detection methods developed on the three widely-used CRISPR/Cas systems (CRISPR/Cas9, CRISPR/Cas12a, and CRISPR/Cas13), and elucidated their biological significance and the principles of action. We also reviewed the recent studies on the applications of CRISPR/Cas systems in pathogen detection, and analyzed the characteristics and possible defects of different detection systems in practical applications. This review aims to provide more constructive advice on developing adaptable and efficient CRISPR/Cas-based detection methods for different pathogens in various practical scenarios.
This study investigated the sensory traits and flavor chemical constituents and their contents of Zhejiang typical particle-shaped famous green teas including Juenong·Cuiming (from Shaoxing, Zhejiang, China), Pingshuirizhu (Shaoxing, Zhejiang, China), and Fenghuaquhao (Ningbo, Zhejiang, China). The differences in sensory characteristics and their key chemical contributors were analyzed. The results showed that there were obvious differences in appearance traits, including tightness, pekoe and color of different typical samples. The Juenong·Cuiming samples show fine and compact granules. The surface of Fenghuaquhao is covered with pekoe and its color is emerald green. For tea taste, Juenong·Cuiming has sweet and mellow taste, while the taste of Fenghuaquhao and Pingshuirizhu are mellow and thick. The gallic acid, catechin, epigallocatechin, epigallocatechin gallate, glutamic acid, arginine, methionine, theanine and γ-aminobutyric acid, etc. were identified as key differential compounds. For tea aroma, Fenghuaquhao is characterized by fresh aroma, while others have tender aroma and moderate toasty aroma. The volatile constituents with fresh and floral aroma such as dihydrolinalool, 1-octanol, and nerol, and volatiles with fruit and sweet aroma such as (E)-nerolidol, 1-nonanal, decanal, 3-nonen-2-one, and α-calacorene, and volatiles produced under high-temperature processing, such as β-ionone epoxide, dihydroactinidiolide, and tea pyrrole, were analyzed to be related with sensory aroma differences. In conclusion, there are obvious differences in appearance, taste, and aroma traits among particle-shaped green teas from different tea producing areas. The sensory differences of particle-shaped green teas were caused by diverse key chemical constituents and their contents, which were induced by tea cultivars, growing environment, and tea processing technology.
