The rice planthopper,Sogatella furcifera,is a piercing-sucking insect pest of rice,Oryza sativa.It is responsible for significant crop yield losses,and has developed moderate to high resistance to several commonly use...The rice planthopper,Sogatella furcifera,is a piercing-sucking insect pest of rice,Oryza sativa.It is responsible for significant crop yield losses,and has developed moderate to high resistance to several commonly used chemical insecticides.We investigated the effects of the insect fungal pathogen Isaria javanica,alone and in combination with the chemical insecticide dinotefuran,on S.furcifera under both laboratory and field conditions.Our results show that I.javanica displays high infection efficiency and mortality for different stages of S.furcifera,reducing adult survival,female oviposition and ovary development.Laboratory bioassays showed that the combined use of I.javanica with a low dose(4-16 mg L^(-1))of dinotefuran resulted in higher mortality in S.furcifera than the use of I.javanica or dinotefuran alone.The combined treatment also had more significant effects on several host enzymes,including superoxide dismutase,catalase,peroxidase,and prophenol oxidase activities.In field trials,I.javanica effectively suppressed populations of rice planthoppers to low levels(22-64%of the level in untreated plots).Additional field experiments showed synergistic effects,i.e.,enhanced efficiency,for the control of S.furcifera populations using the combination of a low dose of I.javanica(1×10^(4) conidia mL^(-1))and a low dose of dinotefuran(~4.8-19.2%of normal field use levels),with control effects of>90%and a population level under 50 insects per 100 hills at 3-14 days post-treatment.Our findings indicate that the entomogenous fungus I.javanica offers an attractive biological control addition as part of the integrated pest management(IPM)practices for the control of rice plant pests.展开更多
Cold-induced sweetening(CIS),the undesirable sugar accumulation in cold-stored potato(Solanum tuberosum L.)tubers,is a severe postharvest issue in the potato processing industry.Although the process of sucrose hydroly...Cold-induced sweetening(CIS),the undesirable sugar accumulation in cold-stored potato(Solanum tuberosum L.)tubers,is a severe postharvest issue in the potato processing industry.Although the process of sucrose hydrolysis by vacuolar invertase during potato CIS is well understood,there is limited knowledge about the transportation of sucrose from the cytosol to the vacuole during postharvest cold storage.Here,we report that among the three potato tonoplast sugar transporters(TSTs),StTST1 exhibits the highest expression in tubers during postharvest cold storage.Subcellular localization analysis demonstrates that StTST1 is a tonoplast-localized protein.StTST1 knockdown decreases reducing sugar accumulation in tubers during low-temperature storage.Compared to wild-type,potato chips produced from StTST1-silenced tubers displayed significantly lower acrylamide levels and lighter color after cold storage.Transcriptome analysis manifests that suppression of StTST1 promotes starch synthesis and inhibits starch degradation in cold-stored tubers.We further establish that the increased sucrose content in the StTST1-silenced tubers might cause a decrease in the ABA content,thereby inhibiting the ABA-signaling pathway.We demonstrate that the down-regulation ofβ-amylase StBAM1 in StTST1-silenced tubers might be directly controlled by ABA-responsive element-binding proteins(AREBs).Altogether,we have shown that StTST1 plays a critical role in sugar accumulation and starchmetabolism regulation during postharvest cold storage.Thus,our findings provide a newstrategy to improve the frying quality of cold-stored tubers and reduce the acrylamide content in potato chips.展开更多
Gingko biloba accumulates high levels of secondary metabolites of pharmaceutical value.Ginkgo calli develop a typical browning that reduces its regenerative capacity and thus its usefulness.To elucidate the browning m...Gingko biloba accumulates high levels of secondary metabolites of pharmaceutical value.Ginkgo calli develop a typical browning that reduces its regenerative capacity and thus its usefulness.To elucidate the browning mechanism,histological,transcriptomic,and metabolic alterations were compared between green and browning calli derived from immature ginkgo embryos.Histological observations revealed that browning calli had a more loosely arranged cell structure and accumulated more tannins than in green calli.Integrated metabolic and transcriptomic analyses showed that phenylpropanoid metabolism was specifi-cally activated in the browning calli,and 428 diff erentially expressed genes and 63 diff erentially abundant metabolites,including 12 fl avonoid compounds,were identifi ed in the browning calli compared to the green calli.Moreover,the expression of fl avonol synthase(FLS)and UDP-glucuronosyl-transferase(UGT)genes involved in the fl avonoid pathway was more than tenfold higher in browning calli than in green calli,thus promoting biosynthesis of fl avonol,which serves as a substrate to form glycosylated fl avonoids.Flavonoid glycosides constituted the major coloring component of the browning calli and may act in response to multiple stress conditions to delay cell death caused by browning.Our results revealed the cellular and biochemical changes in browning callus cells that accompanied changes in expression of browning-related genes,providing a scientifi c basis for improving ginkgo tissue culturability.展开更多
Gardeniae Fructus(GF)and Semen Sojae Praeparatum(SSP)are both medicine food homologies and widely used in Chinese clinical prescriptions together.The research investigated the pharmacokinetics of four iridoids in norm...Gardeniae Fructus(GF)and Semen Sojae Praeparatum(SSP)are both medicine food homologies and widely used in Chinese clinical prescriptions together.The research investigated the pharmacokinetics of four iridoids in normal rats and isolfavones-fed rats,which were administered with isolfavones from SSP for 7,14,21 and 28 consecutive days.A validated LC-MS/MS method was developed for determining shanzhiside,genipin-1-gentiobioside,geniposide and their metabolite genipin in rat plasma.Plasma samples were pretreated by solid-phase extraction using paeoniflorin as the internal standard.The chromatographic separation was performed on a Waters Atlantis T3(4.6 mm×150 mm,3 mm)column using a gradient mobile phase consisting of acetonitril and water(containing 0.06%acetic acid).The mass detection was under the multiple reaction monitoring(MRM)mode via polarity switching between negative and positive ionization modes.The calibration curves exhibited good linearity(r>0.997)for all components.The lower limit of quantitation was in the range of 1 e10 ng/m L.The intra-day and inter-day precisions(RSD)at three different levels were both less than 12.2%and the accuracies(RE)ranged fromà10.1%to 16.4%.The extraction recovery of them ranged from 53.8%to 99.7%.Pharmacokinetic results indicated the bioavailability of three iridoid glycosides and the metabolite,genipin in normal rats was higher than that in rats exposed to isoflavones.With the longer time of administration of isoflavones,plasma concentrations of iridoids decreased,while genipin sulfate,the phase II metabolite of genposide and genipin-1-gentiobioside,appeared the rising exposure.The pharmacokinetic profiles of main iridoids from GF were altered by isoflavones.展开更多
Ginkgo biloba is a famous living“fossil”and has played an important role in the evolution of the Plant Kingdom.Here,the complete chloroplast genome of G.biloba was sequenced and analysed.The chloroplast genome was 1...Ginkgo biloba is a famous living“fossil”and has played an important role in the evolution of the Plant Kingdom.Here,the complete chloroplast genome of G.biloba was sequenced and analysed.The chloroplast genome was 156,990 bp long and predicted to encode 134 genes including 85 protein-coding genes,41 tRNA genes and 8 rRNA genes.The chloroplast genome has a typical quadripartite structure with a pair of inverted repeat regions(IRa and IRb,17,732 bp),a large(LSC,99,259 bp)and small single(SSC,22,267 bp)copy region.After an extensive comparison to previously published gymnosperm plastomes,the gene content and organisation of G.biloba showed high divergence,although part was relatively conserved.The two typical IR regions in the G.biloba chloroplast genome were relatively shorter because it the ycf2 gene.In addition,it was obvious that the IR regions and gene loss were responsible for changes in chloroplast genome size and structure stability,which influenced plastome evolution in different gymnosperms.Phylogenetic analysis revealed that G.biloba is sister to cycads rather than to gnetophytes,cupressophytes,and Pinaceae.Overall,the study showed that the genomic characteristics of G.biloba would be of great help in the further research on the taxonomy,species identification and evolutionary history of gymnosperms,especially for their position in plant systematics and evolution.展开更多
When a mass of individual targets move closely, it is unpractical or unnecessary to localize and track every specific target in wireless sensor networks (WSN). However, they can be tracked as a whole by view of group ...When a mass of individual targets move closely, it is unpractical or unnecessary to localize and track every specific target in wireless sensor networks (WSN). However, they can be tracked as a whole by view of group target. In order to decrease the amount of energy spent on active sensing and communications, a flexible boundary detecting model for group target tracking in WSN is proposed, in which, the number of sensors involved in target tracking is adjustable. Unlike traditional one or multiple individual targets, the group target usually occupies a large area. To obtain global estimated position of group target, a divide-merge algorithm using convex hull is designed. In this algorithm, group target’s boundary is divided into several small pieces, and each one is enclosed by a convex hull which is constructed by a cluster of boundary sensors. Then, the information of these small convex hulls is sent back to a sink. Finally, big convex hull merged from these small ones is considered as the group target’s contour. According to our metric of precision evaluation, the simulation experiments confirm the efficiency and accuracy of this algorithm.展开更多
[Objectives]This study was conducted to explore the control mechanism of agricultural non-point source pollution,and investigate the feasibility of promoting rice"three controls"nutrient management in Enping...[Objectives]This study was conducted to explore the control mechanism of agricultural non-point source pollution,and investigate the feasibility of promoting rice"three controls"nutrient management in Enping City.[Methods]With high-quality conventional rice as a material,such three treatments as three controls fertilization A(ZHY)and B(ZHY)and farmers conventional fertilization method FFP(ZXL)were set up,and the whole process of the late-season plot experiment was recorded.The agronomic characteristics of rice population quality and yield components during rice growth and development under the"three controls"fertilization technology were analyzed.[Results]Compared with the conventional fertilization method,the three controls A(ZHY)fertilization method improved rice yield by 27.13%,seed setting rate by 2.11%and 1 000-grain weight by 3.30%when reducing N,P and K by 27.13%,10.89%and 27.31%,respectively.In the case of three controls B(ZHY)omitting the last fertilization in the three controls fertilization method(4∶2∶3∶1),which saved the formula fertilizer by 11.25%,no difference was caused in yield,but the seed setting rate and 1 000-grain weight were still improved by 3.47%and 2.79%,respectively.Compared with the conventional fertilization method,the top first,second and third basal nodes of the three controls A(ZHY)fertilization method were shortened by 18.82%,17.06%and 20.52%,respectively,which plays an important role in combating typhoon and resisting lodging.[Conclusions]Compared with the conventional fertilization method,rice"three controls"nutrient management can improve yield and lodging resistance of rice,reduce fertilizer loss and agricultural non-point source pollution,and protect ecological environment.展开更多
The Alternaria alternata apple pathotype adversely affects apple(Malus domestica Borkh.)cultivation.However,the molecular mechanisms underlying enhanced resistance to this pathogen in apple remain poorly understood.We...The Alternaria alternata apple pathotype adversely affects apple(Malus domestica Borkh.)cultivation.However,the molecular mechanisms underlying enhanced resistance to this pathogen in apple remain poorly understood.We have previously reported that MdWRKY75 expression is upregulated by A.alternata infection in‘Sushuai’apples.In this study,we discovered that overexpression of MdWRKY75e increased the resistance of transgenic apple lines to A.alternata infection,whereas silencing this gene enhanced susceptibility to A.alternata infection.Furthermore,we found that MdWRKY75e directly binds to the MdLAC7 promoter to regulate the biosynthesis of laccase and increase the biosynthesis of lignin during A.alternata infection.Moreover,the thickening of the cell wall enhanced the mechanical defense capabilities of apple.In addition,we found that jasmonic acid remarkably induced MdWRKY75e expression,and its levels in transgenic apple lines were elevated.These results indicate that MdWRKY75e confers resistance to the A.alternata apple pathotype mainly via the jasmonic acid pathway and that pathogenesis-related genes and antioxidant-related enzyme activity are involved in the disease resistance of MdWRKY75e transgenic plants.In conclusion,our fi ndings provide insights into the importance of MdWRKY75e for resistance to A.alternata infection in apples.展开更多
[Objectives]This study was conducted to investigate the purification effects of two common large seaweeds on the tail water of prawn farming in greenhouses,and to determine the best culture density of seaweeds.[Method...[Objectives]This study was conducted to investigate the purification effects of two common large seaweeds on the tail water of prawn farming in greenhouses,and to determine the best culture density of seaweeds.[Methods]Two large seaweed species,Gracilaria lichevoides and Ulva lactuca,were selected to set four culture densities of 0.5,2,4 g/L and a blank control group,respectively.The seaweeds were cultured in 100 L white polyethylene buckets,each of which contained 50 L of tail water from prawn culture.[Results]After 5 d,the nutrient removal rates of the two seaweeds were directly proportional to the density.There was no significant difference in NH_(4)-N removal rate between G.lichevoides and U.lactuca(P>0.05)by two-way analysis of variance,and the NH_(4)-N removal rate of the latter was higher.The removal rates of NO_(3)-N,TN and TP by G.lichevoides were significantly higher than those by U.lactuca(P<0.05).The specific growth rates of seaweeds were negatively correlated with their culture densities.The specific growth rates of G.lichevoides were 5.73%,1.654%and 0.48%,respectively,and those of U.lactuca were 2.01%,1.187%and 0.138%,respectively,when the culture densities were 0.5,2.0 and 4.0 g/L.Two-factor analysis of variance showed that the former was significantly higher than the latter,when the culture density of the two species of seaweeds was 0.5 g/L(P<0.05).The two-way analysis of variance showed that when the culture density of the two kinds of seaweeds was 0.5 g/L,the specific growth rate of G.lichevoides was significantly higher than that of U.lactuca(P<0.05).Based on the above research,the two macroalgae could reduce the nutrients in the wastewater to a large extent,but the culture density determined the scale and economic benefits of seaweed cultivation and further affected the normal growth,metabolism and quality of the seaweeds.[Conclusions]This study provides some theoretical basis for large-scale seaweed farming and biological selection of in-situ ecological restoration of eutrophic seawater.展开更多
[Objectives]To provide a theoretical basis for constructing the best species suitable for local shrimp-bivalves-algae IMTA through the screening of different bivalves and the determination of seaweed density.[Methods]...[Objectives]To provide a theoretical basis for constructing the best species suitable for local shrimp-bivalves-algae IMTA through the screening of different bivalves and the determination of seaweed density.[Methods]The preliminary studies of different kind of bivalves and macroalgae(Gracilaria lichevoides)used for the purification of shrimp effluent were described.Through the screening of benthic bivalves,the best ratio of integrated culture of bivalves and algae was determined.[Results]Both bivalves and macroalgae had certain purification effects on aquaculture wastewater,but the effects significantly differed from species and breeding density.The removal rate of nutrient declined from Potamocorbula laevis,Sinonovacula constricta,Tegillarca granosa.The mixotrophic culture of 8 ind/L P.laevis and 120 g G.lichevoides had the highest efficiency of purification and removal rates of nutrient:NH4-N:90.67%,TP:86.18%,TN:72.66%,NO3-N:51.85%,respectively.There was a significant difference between the blank control group and the other three groups(P<0.01).The 8 ind/L+120 g group was significantly higher than the 4 ind/L+120 g group(P<0.05)in TP removal rate.Additionally,the difference between four groups was significant in the removal rate of NH4-N and TN(P<0.05),but 2 ind/L+120 g group and 8 ind/L+120 g group in the removal rate of NO3-N had no significant difference(P>0.05).[Conclusions]This research provides a reference for the use of filterable shellfish and large seaweed to treat aquaculture wastewater,and also provides the theoretical basis for constructing the local multi-level breeding structure.展开更多
Eucalyptus is a genus of over 900 species and hybrids,and many of them are valuable fast-growing hardwoods.Due to its economic importance,Eucalyptus is one of the early tree species whose genomes were deciphered.Howev...Eucalyptus is a genus of over 900 species and hybrids,and many of them are valuable fast-growing hardwoods.Due to its economic importance,Eucalyptus is one of the early tree species whose genomes were deciphered.However,the lack of efficient genetic transformation systems severely restricts the functional genomic research on the plant.The success of Eucalyptus regeneration and transformation depends greatly on the genotypes and explants.In this study,we systematically screened 26 genotypes from 12 Eucalyptus species in an attempt to obtain Eucalyptus genotypes with high regeneration potential.We developed two common regeneration media that can be applied to most tested Eucalyptus genotypes for both seeding hypocotyls and cloned internodes as explants.We then implemented DsRed2 as a visual marker for genetic transformation efficiency test.Our results suggest that E.camaldulen and E.robusta are amenable for genetic transformation.Finally,we successfully set up a stable Agrobacterium-mediated genetic transformation procedure for both E.camaldulen and E.robusta using seeding hypocotyls and cloned internodes respectively.Taken together,our study provides valuable means for vegetative propagation,gene transformation,CRISPR based gene mutagenesis,activation and suppression,as well as functional characterization of genes in Eucalyptus.展开更多
In our previous study,a heat-induced differentially expressed WRKY-IIe gene LlWRKY22 is isolated from lily(Lilium longiflorum),which acts as a positive role in thermotolerance,but whether it is involved in other stres...In our previous study,a heat-induced differentially expressed WRKY-IIe gene LlWRKY22 is isolated from lily(Lilium longiflorum),which acts as a positive role in thermotolerance,but whether it is involved in other stress responses is unknown.Here,the expression of LlWRKY22 was indicated to be positively influenced by heat,salt,or mannitol treatments,and its promoter activity was also enhanced after heat,salt,or mannitol treatments.In addition,LlWRKY22 responded to ABA treatment,which activated its expression and also increased the promoter activity.Overexpression of LlWRKY22 in Arabidopsis contributed to growth defects and early flowering.Simultaneously,compared with the wild type,the ABA sensitivity in transgenic lines was increased in both the germination stage and late growth stage.Further analysis showed that LlWRKY22 overexpression elevated the thermotolerance of transgenic plants and induced the expression of AtDREB2A,AtDREB2B,AtDREB2C,and AtJUB1.The salt and mannitol tolerances of the overexpression lines were also improved.Overall,our results illustrated that LlWRKY22 is affected by heat,salt,and osmotic stresses,and positively regulates heat,salt,and osmotic tolerances,which reveals that it acts as a generalist character responding to different abiotic stresses.And further to that,the regulatory pathway of LlWRKY22 also involves in ABA signaling.展开更多
With the fast-growing graphical user interface(GUI)development workload in the Internet industry,some work attempted to generate maintainable front-end code from GUI screenshots.It can be more suitable for using user ...With the fast-growing graphical user interface(GUI)development workload in the Internet industry,some work attempted to generate maintainable front-end code from GUI screenshots.It can be more suitable for using user interface(UI)design drafts that contain UI metadata.However,fragmented layers inevitably appear in the UI design drafts,which greatly reduces the quality of the generated code.None of the existing automated GUI techniques detects and merges the fragmented layers to improve the accessibility of generated code.In this paper,we propose UI layers merger(UILM),a vision-based method that can automatically detect and merge fragmented layers into UI components.Our UILM contains the merging area detector(MAD)and a layer merging algorithm.The MAD incorporates the boundary prior knowledge to accurately detect the boundaries of UI components.Then,the layer merging algorithm can search for the associated layers within the components’boundaries and merge them into a whole.We present a dynamic data augmentation approach to boost the performance of MAD.We also construct a large-scale UI dataset for training the MAD and testing the performance of UILM.Experimental results show that the proposed method outperforms the best baseline regarding merging area detection and achieves decent layer merging accuracy.A user study on a real application also confirms the effectiveness of our UILM.展开更多
Currently,display-based methods are well established and widely used in antibody engineering for affinity maturation and structural stability improvement.We obtained a novel anti-human programmed death 1(PD-1)antibody...Currently,display-based methods are well established and widely used in antibody engineering for affinity maturation and structural stability improvement.We obtained a novel anti-human programmed death 1(PD-1)antibody using computer-aided design and a mammalian cell display technology platform.We used computer-aided modeling and distance geometry methods to predict and assign the key residues that contributed to the binding of human PD-L1 to PD-1.Then,we analyzed the sequence of nivolumab(an anti-human PD-1 antibody,referred to as MIL75 in the article)to determine the template for antibody design and library construction.We identified a series of potential substitutions on the obtained template and constructed a virtual epitope-targeted antibody library based on the physicochemical properties and each possible location of the assigned key residues.The virtual antibody libraries were displayed on the surface of mammalian cells as the antigen-binding fragments of full-length immunoglobulin G.Then,we used flow cytometry and sequencing approaches to sort and screen the candidates.Finally,we obtained a novel anti-human PD-1 antibody named FV78.FV78 competitively recognized the PD-1 epitopes that interacted with MIL75 and possessed an affinity comparable to MIL75.Our results implied that FV78 possessed equivalent bioactivity in vitro and in vivo compared with MIL75,which highlighted the probability and prospect of FV78 becoming a new potential antibody therapy.展开更多
【目的】圣路易斯脑炎病毒(St. Louis encephalitis virus,SLEV)属于黄病毒科,是一种单股正链RNA病毒。黄病毒编码的非结构蛋白NS3在病毒复制以及多聚蛋白加工过程中起着重要作用,NS2B是其发挥作用的重要辅助因子。因此,NS2B-NS3蛋白酶...【目的】圣路易斯脑炎病毒(St. Louis encephalitis virus,SLEV)属于黄病毒科,是一种单股正链RNA病毒。黄病毒编码的非结构蛋白NS3在病毒复制以及多聚蛋白加工过程中起着重要作用,NS2B是其发挥作用的重要辅助因子。因此,NS2B-NS3蛋白酶复合物是抗病毒药物的重要靶标。本研究旨在构建SLEV NS2B-NS3蛋白酶的原核表达系统并建立其抑制剂的高通量筛选方法,从而发现其小分子抑制剂。【方法】通过PCR扩增SLEVNS2B-NS3蛋白的编码区,构建原核表达质粒;在大肠杆菌BL21(DE3)中,经异丙基硫代半乳糖苷(Isopropyl β-D-thiogalactoside)诱导得到可溶性的NS2B-NS3蛋白,并用镍亲和层析方法进行纯化;基于荧光共振能量转移(Fluorescence resonance energy transfer)技术检测NS2B-NS3蛋白酶活性,建立其抑制剂的高通量筛选平台。【结果】SLEV NS2B-NS3蛋白酶纯化程度高达95%以上,基于酶活测定的抑制剂筛选平台准确可行。对700多个上市药物进行筛选后,发现原花青素对SLEVNS2B-NS3蛋白酶具有明显的抑制活性。【结论】本研究为SLEVNS2B-NS3蛋白酶抑制剂提供了一种操作方便、高通量的筛选方法,并首次发现了原花青素具有抑制SLEV NS2B-NS3蛋白酶活性的功能,可以作为治疗SLEV感染的潜在靶向药物。展开更多
Modulating the surface coordination environment of Pt based nanocrystals at the atomic level is of great importance to obtain good electrocatalytic performance.Given the fundamental understandings of surface structure...Modulating the surface coordination environment of Pt based nanocrystals at the atomic level is of great importance to obtain good electrocatalytic performance.Given the fundamental understandings of surface structure degeneration of Pt based nanocrystals,introducing a weak electronegative element to the surface of Pt-based catalysts is beneficial for suppressing surface passivation and improving hydrogen evolution reaction performance of Pt.Density functional theory results reveal that the energy barrier of water dissociation process can be greatly reduced by using Se element as the surface modifier to replace the O.This hypothesis is further validated by experiments that ultralong Pt_(85)Mo_(15)-Se nanowires were fabricated to suppress the excessive passivation behavior of transition metals of Pt based alloy.The Pt_(85)Mo_(15)-Se nanowires exhibit higher activity with 4.98 times the specific activity and 4.87 times the mass activity of commercial Pt/C,as well as a better stability towards alkaline hydrogen evolution reaction.The deep exploration of X-ray photoelectron spectroscopy and theoretical calculations disclose that Se element could maintain the electron-rich state around the electronic orbit of Pt.This study provides a new insight to advance the fundamental understanding on electrocatalytic materials,which exhibits a promising approach to protect the surface chemical environment of Pt based nanocrystals.展开更多
基金funded by grants from the Science and Technology Planning Project of Guangzhou,China(202002020029)the Science and Technology Planning Project of Guangdong Province,China(2019B020217003)+1 种基金the National Key R&D Program of China(2018YFD02003)the National Key Technology Support Program of China(201303019-02)。
文摘The rice planthopper,Sogatella furcifera,is a piercing-sucking insect pest of rice,Oryza sativa.It is responsible for significant crop yield losses,and has developed moderate to high resistance to several commonly used chemical insecticides.We investigated the effects of the insect fungal pathogen Isaria javanica,alone and in combination with the chemical insecticide dinotefuran,on S.furcifera under both laboratory and field conditions.Our results show that I.javanica displays high infection efficiency and mortality for different stages of S.furcifera,reducing adult survival,female oviposition and ovary development.Laboratory bioassays showed that the combined use of I.javanica with a low dose(4-16 mg L^(-1))of dinotefuran resulted in higher mortality in S.furcifera than the use of I.javanica or dinotefuran alone.The combined treatment also had more significant effects on several host enzymes,including superoxide dismutase,catalase,peroxidase,and prophenol oxidase activities.In field trials,I.javanica effectively suppressed populations of rice planthoppers to low levels(22-64%of the level in untreated plots).Additional field experiments showed synergistic effects,i.e.,enhanced efficiency,for the control of S.furcifera populations using the combination of a low dose of I.javanica(1×10^(4) conidia mL^(-1))and a low dose of dinotefuran(~4.8-19.2%of normal field use levels),with control effects of>90%and a population level under 50 insects per 100 hills at 3-14 days post-treatment.Our findings indicate that the entomogenous fungus I.javanica offers an attractive biological control addition as part of the integrated pest management(IPM)practices for the control of rice plant pests.
基金supported by the National Natural Science Foundation of China(31871683 and 32101781)the earmarked fund for the China Modern Agro-industry Technology Research System(CARS-09,Potato).
文摘Cold-induced sweetening(CIS),the undesirable sugar accumulation in cold-stored potato(Solanum tuberosum L.)tubers,is a severe postharvest issue in the potato processing industry.Although the process of sucrose hydrolysis by vacuolar invertase during potato CIS is well understood,there is limited knowledge about the transportation of sucrose from the cytosol to the vacuole during postharvest cold storage.Here,we report that among the three potato tonoplast sugar transporters(TSTs),StTST1 exhibits the highest expression in tubers during postharvest cold storage.Subcellular localization analysis demonstrates that StTST1 is a tonoplast-localized protein.StTST1 knockdown decreases reducing sugar accumulation in tubers during low-temperature storage.Compared to wild-type,potato chips produced from StTST1-silenced tubers displayed significantly lower acrylamide levels and lighter color after cold storage.Transcriptome analysis manifests that suppression of StTST1 promotes starch synthesis and inhibits starch degradation in cold-stored tubers.We further establish that the increased sucrose content in the StTST1-silenced tubers might cause a decrease in the ABA content,thereby inhibiting the ABA-signaling pathway.We demonstrate that the down-regulation ofβ-amylase StBAM1 in StTST1-silenced tubers might be directly controlled by ABA-responsive element-binding proteins(AREBs).Altogether,we have shown that StTST1 plays a critical role in sugar accumulation and starchmetabolism regulation during postharvest cold storage.Thus,our findings provide a newstrategy to improve the frying quality of cold-stored tubers and reduce the acrylamide content in potato chips.
基金supported by the Natural Science Foundation of Jiangsu Province(BK20210611)the China Postdoctoral Science Foundation(2018M642261)+2 种基金the Postdoctoral Science Foundation of Jiangsu Province(2018K197C)the Jiangsu Science and Technology Plan Project(BE2021367)the National Natural Science Foundation of China(31971689).
文摘Gingko biloba accumulates high levels of secondary metabolites of pharmaceutical value.Ginkgo calli develop a typical browning that reduces its regenerative capacity and thus its usefulness.To elucidate the browning mechanism,histological,transcriptomic,and metabolic alterations were compared between green and browning calli derived from immature ginkgo embryos.Histological observations revealed that browning calli had a more loosely arranged cell structure and accumulated more tannins than in green calli.Integrated metabolic and transcriptomic analyses showed that phenylpropanoid metabolism was specifi-cally activated in the browning calli,and 428 diff erentially expressed genes and 63 diff erentially abundant metabolites,including 12 fl avonoid compounds,were identifi ed in the browning calli compared to the green calli.Moreover,the expression of fl avonol synthase(FLS)and UDP-glucuronosyl-transferase(UGT)genes involved in the fl avonoid pathway was more than tenfold higher in browning calli than in green calli,thus promoting biosynthesis of fl avonol,which serves as a substrate to form glycosylated fl avonoids.Flavonoid glycosides constituted the major coloring component of the browning calli and may act in response to multiple stress conditions to delay cell death caused by browning.Our results revealed the cellular and biochemical changes in browning callus cells that accompanied changes in expression of browning-related genes,providing a scientifi c basis for improving ginkgo tissue culturability.
基金the National Natural Science Foundation of China(grant numbers 81573584,81773862)。
文摘Gardeniae Fructus(GF)and Semen Sojae Praeparatum(SSP)are both medicine food homologies and widely used in Chinese clinical prescriptions together.The research investigated the pharmacokinetics of four iridoids in normal rats and isolfavones-fed rats,which were administered with isolfavones from SSP for 7,14,21 and 28 consecutive days.A validated LC-MS/MS method was developed for determining shanzhiside,genipin-1-gentiobioside,geniposide and their metabolite genipin in rat plasma.Plasma samples were pretreated by solid-phase extraction using paeoniflorin as the internal standard.The chromatographic separation was performed on a Waters Atlantis T3(4.6 mm×150 mm,3 mm)column using a gradient mobile phase consisting of acetonitril and water(containing 0.06%acetic acid).The mass detection was under the multiple reaction monitoring(MRM)mode via polarity switching between negative and positive ionization modes.The calibration curves exhibited good linearity(r>0.997)for all components.The lower limit of quantitation was in the range of 1 e10 ng/m L.The intra-day and inter-day precisions(RSD)at three different levels were both less than 12.2%and the accuracies(RE)ranged fromà10.1%to 16.4%.The extraction recovery of them ranged from 53.8%to 99.7%.Pharmacokinetic results indicated the bioavailability of three iridoid glycosides and the metabolite,genipin in normal rats was higher than that in rats exposed to isoflavones.With the longer time of administration of isoflavones,plasma concentrations of iridoids decreased,while genipin sulfate,the phase II metabolite of genposide and genipin-1-gentiobioside,appeared the rising exposure.The pharmacokinetic profiles of main iridoids from GF were altered by isoflavones.
基金supported by the Key Forestry Public Welfare Project of China(201504105)the National Key Research and Development Program of China(2017YFD0600700)the Agricultural Science and Technology Independent Innovation Funds of Jiangsu Province[CX(16)1005].
文摘Ginkgo biloba is a famous living“fossil”and has played an important role in the evolution of the Plant Kingdom.Here,the complete chloroplast genome of G.biloba was sequenced and analysed.The chloroplast genome was 156,990 bp long and predicted to encode 134 genes including 85 protein-coding genes,41 tRNA genes and 8 rRNA genes.The chloroplast genome has a typical quadripartite structure with a pair of inverted repeat regions(IRa and IRb,17,732 bp),a large(LSC,99,259 bp)and small single(SSC,22,267 bp)copy region.After an extensive comparison to previously published gymnosperm plastomes,the gene content and organisation of G.biloba showed high divergence,although part was relatively conserved.The two typical IR regions in the G.biloba chloroplast genome were relatively shorter because it the ycf2 gene.In addition,it was obvious that the IR regions and gene loss were responsible for changes in chloroplast genome size and structure stability,which influenced plastome evolution in different gymnosperms.Phylogenetic analysis revealed that G.biloba is sister to cycads rather than to gnetophytes,cupressophytes,and Pinaceae.Overall,the study showed that the genomic characteristics of G.biloba would be of great help in the further research on the taxonomy,species identification and evolutionary history of gymnosperms,especially for their position in plant systematics and evolution.
文摘When a mass of individual targets move closely, it is unpractical or unnecessary to localize and track every specific target in wireless sensor networks (WSN). However, they can be tracked as a whole by view of group target. In order to decrease the amount of energy spent on active sensing and communications, a flexible boundary detecting model for group target tracking in WSN is proposed, in which, the number of sensors involved in target tracking is adjustable. Unlike traditional one or multiple individual targets, the group target usually occupies a large area. To obtain global estimated position of group target, a divide-merge algorithm using convex hull is designed. In this algorithm, group target’s boundary is divided into several small pieces, and each one is enclosed by a convex hull which is constructed by a cluster of boundary sensors. Then, the information of these small convex hulls is sent back to a sink. Finally, big convex hull merged from these small ones is considered as the group target’s contour. According to our metric of precision evaluation, the simulation experiments confirm the efficiency and accuracy of this algorithm.
基金Supported by Enping City Science and Technology Program(2017)
文摘[Objectives]This study was conducted to explore the control mechanism of agricultural non-point source pollution,and investigate the feasibility of promoting rice"three controls"nutrient management in Enping City.[Methods]With high-quality conventional rice as a material,such three treatments as three controls fertilization A(ZHY)and B(ZHY)and farmers conventional fertilization method FFP(ZXL)were set up,and the whole process of the late-season plot experiment was recorded.The agronomic characteristics of rice population quality and yield components during rice growth and development under the"three controls"fertilization technology were analyzed.[Results]Compared with the conventional fertilization method,the three controls A(ZHY)fertilization method improved rice yield by 27.13%,seed setting rate by 2.11%and 1 000-grain weight by 3.30%when reducing N,P and K by 27.13%,10.89%and 27.31%,respectively.In the case of three controls B(ZHY)omitting the last fertilization in the three controls fertilization method(4∶2∶3∶1),which saved the formula fertilizer by 11.25%,no difference was caused in yield,but the seed setting rate and 1 000-grain weight were still improved by 3.47%and 2.79%,respectively.Compared with the conventional fertilization method,the top first,second and third basal nodes of the three controls A(ZHY)fertilization method were shortened by 18.82%,17.06%and 20.52%,respectively,which plays an important role in combating typhoon and resisting lodging.[Conclusions]Compared with the conventional fertilization method,rice"three controls"nutrient management can improve yield and lodging resistance of rice,reduce fertilizer loss and agricultural non-point source pollution,and protect ecological environment.
基金This work was supported by the National Natural Science Foundation of China(grant number 31872074)the National Key R&D Program of China(2019YFD1000100)Priority Academic Program Development of Jiangsu Higher Education Institutions。
文摘The Alternaria alternata apple pathotype adversely affects apple(Malus domestica Borkh.)cultivation.However,the molecular mechanisms underlying enhanced resistance to this pathogen in apple remain poorly understood.We have previously reported that MdWRKY75 expression is upregulated by A.alternata infection in‘Sushuai’apples.In this study,we discovered that overexpression of MdWRKY75e increased the resistance of transgenic apple lines to A.alternata infection,whereas silencing this gene enhanced susceptibility to A.alternata infection.Furthermore,we found that MdWRKY75e directly binds to the MdLAC7 promoter to regulate the biosynthesis of laccase and increase the biosynthesis of lignin during A.alternata infection.Moreover,the thickening of the cell wall enhanced the mechanical defense capabilities of apple.In addition,we found that jasmonic acid remarkably induced MdWRKY75e expression,and its levels in transgenic apple lines were elevated.These results indicate that MdWRKY75e confers resistance to the A.alternata apple pathotype mainly via the jasmonic acid pathway and that pathogenesis-related genes and antioxidant-related enzyme activity are involved in the disease resistance of MdWRKY75e transgenic plants.In conclusion,our fi ndings provide insights into the importance of MdWRKY75e for resistance to A.alternata infection in apples.
基金Ningbo City's 2015 Science and Technology Project for Enriching People:Optimization and Promotion of Prawn,Shellfish and Algae Ponds Integrated Aquaculture Technology(2015C10008)Ningbo Science and Technology Planning Project(2019C10039)+1 种基金Research and Development Project of Ecological and Efficient Clean Aquaculture of Mudflat Shellfish(2019C02054)China Shellfish Research System(CARS-49).
文摘[Objectives]This study was conducted to investigate the purification effects of two common large seaweeds on the tail water of prawn farming in greenhouses,and to determine the best culture density of seaweeds.[Methods]Two large seaweed species,Gracilaria lichevoides and Ulva lactuca,were selected to set four culture densities of 0.5,2,4 g/L and a blank control group,respectively.The seaweeds were cultured in 100 L white polyethylene buckets,each of which contained 50 L of tail water from prawn culture.[Results]After 5 d,the nutrient removal rates of the two seaweeds were directly proportional to the density.There was no significant difference in NH_(4)-N removal rate between G.lichevoides and U.lactuca(P>0.05)by two-way analysis of variance,and the NH_(4)-N removal rate of the latter was higher.The removal rates of NO_(3)-N,TN and TP by G.lichevoides were significantly higher than those by U.lactuca(P<0.05).The specific growth rates of seaweeds were negatively correlated with their culture densities.The specific growth rates of G.lichevoides were 5.73%,1.654%and 0.48%,respectively,and those of U.lactuca were 2.01%,1.187%and 0.138%,respectively,when the culture densities were 0.5,2.0 and 4.0 g/L.Two-factor analysis of variance showed that the former was significantly higher than the latter,when the culture density of the two species of seaweeds was 0.5 g/L(P<0.05).The two-way analysis of variance showed that when the culture density of the two kinds of seaweeds was 0.5 g/L,the specific growth rate of G.lichevoides was significantly higher than that of U.lactuca(P<0.05).Based on the above research,the two macroalgae could reduce the nutrients in the wastewater to a large extent,but the culture density determined the scale and economic benefits of seaweed cultivation and further affected the normal growth,metabolism and quality of the seaweeds.[Conclusions]This study provides some theoretical basis for large-scale seaweed farming and biological selection of in-situ ecological restoration of eutrophic seawater.
基金Ningbo Science and Technology Project of Enriching the People in 2015(2015C10008)Ningbo Science and Technology Plan Project(2019C10039)+1 种基金Zhejiang Science and Technology Plan Project(2019C02054)Special Project for the Construction of Modern Agricultural Industrial Technology System(CARS-49).
文摘[Objectives]To provide a theoretical basis for constructing the best species suitable for local shrimp-bivalves-algae IMTA through the screening of different bivalves and the determination of seaweed density.[Methods]The preliminary studies of different kind of bivalves and macroalgae(Gracilaria lichevoides)used for the purification of shrimp effluent were described.Through the screening of benthic bivalves,the best ratio of integrated culture of bivalves and algae was determined.[Results]Both bivalves and macroalgae had certain purification effects on aquaculture wastewater,but the effects significantly differed from species and breeding density.The removal rate of nutrient declined from Potamocorbula laevis,Sinonovacula constricta,Tegillarca granosa.The mixotrophic culture of 8 ind/L P.laevis and 120 g G.lichevoides had the highest efficiency of purification and removal rates of nutrient:NH4-N:90.67%,TP:86.18%,TN:72.66%,NO3-N:51.85%,respectively.There was a significant difference between the blank control group and the other three groups(P<0.01).The 8 ind/L+120 g group was significantly higher than the 4 ind/L+120 g group(P<0.05)in TP removal rate.Additionally,the difference between four groups was significant in the removal rate of NH4-N and TN(P<0.05),but 2 ind/L+120 g group and 8 ind/L+120 g group in the removal rate of NO3-N had no significant difference(P>0.05).[Conclusions]This research provides a reference for the use of filterable shellfish and large seaweed to treat aquaculture wastewater,and also provides the theoretical basis for constructing the local multi-level breeding structure.
基金supported by the National Natural Science Foundation of China(31971676)the Opening Project of State Key Laboratory of Tree Genetics and Breeding(K2020103)the Fundamental Research Funds for Central Universities(2662019PY007)。
文摘Eucalyptus is a genus of over 900 species and hybrids,and many of them are valuable fast-growing hardwoods.Due to its economic importance,Eucalyptus is one of the early tree species whose genomes were deciphered.However,the lack of efficient genetic transformation systems severely restricts the functional genomic research on the plant.The success of Eucalyptus regeneration and transformation depends greatly on the genotypes and explants.In this study,we systematically screened 26 genotypes from 12 Eucalyptus species in an attempt to obtain Eucalyptus genotypes with high regeneration potential.We developed two common regeneration media that can be applied to most tested Eucalyptus genotypes for both seeding hypocotyls and cloned internodes as explants.We then implemented DsRed2 as a visual marker for genetic transformation efficiency test.Our results suggest that E.camaldulen and E.robusta are amenable for genetic transformation.Finally,we successfully set up a stable Agrobacterium-mediated genetic transformation procedure for both E.camaldulen and E.robusta using seeding hypocotyls and cloned internodes respectively.Taken together,our study provides valuable means for vegetative propagation,gene transformation,CRISPR based gene mutagenesis,activation and suppression,as well as functional characterization of genes in Eucalyptus.
基金supported by the National Natural Science Foundation of China(31902055)the Fundamental Research Funds for the Central Universities(KYZZ2022004)+1 种基金the National Key R&D Program of China(2019YFD1000400)the Natural Science Foundation of Jiangsu Province,China(BK20190532).
文摘In our previous study,a heat-induced differentially expressed WRKY-IIe gene LlWRKY22 is isolated from lily(Lilium longiflorum),which acts as a positive role in thermotolerance,but whether it is involved in other stress responses is unknown.Here,the expression of LlWRKY22 was indicated to be positively influenced by heat,salt,or mannitol treatments,and its promoter activity was also enhanced after heat,salt,or mannitol treatments.In addition,LlWRKY22 responded to ABA treatment,which activated its expression and also increased the promoter activity.Overexpression of LlWRKY22 in Arabidopsis contributed to growth defects and early flowering.Simultaneously,compared with the wild type,the ABA sensitivity in transgenic lines was increased in both the germination stage and late growth stage.Further analysis showed that LlWRKY22 overexpression elevated the thermotolerance of transgenic plants and induced the expression of AtDREB2A,AtDREB2B,AtDREB2C,and AtJUB1.The salt and mannitol tolerances of the overexpression lines were also improved.Overall,our results illustrated that LlWRKY22 is affected by heat,salt,and osmotic stresses,and positively regulates heat,salt,and osmotic tolerances,which reveals that it acts as a generalist character responding to different abiotic stresses.And further to that,the regulatory pathway of LlWRKY22 also involves in ABA signaling.
基金Project supported by the National Key R&D Program of China(No.2018AAA0100703)the National Natural Science Foundation of China(Nos.62006208 and 62107035)+1 种基金the Ng Teng Fong Charitable Foundation in the form of ZJU-SUTD IDEA Grantthe Alibaba-Zhejiang University Joint Research Institute of Frontier Technologies。
文摘With the fast-growing graphical user interface(GUI)development workload in the Internet industry,some work attempted to generate maintainable front-end code from GUI screenshots.It can be more suitable for using user interface(UI)design drafts that contain UI metadata.However,fragmented layers inevitably appear in the UI design drafts,which greatly reduces the quality of the generated code.None of the existing automated GUI techniques detects and merges the fragmented layers to improve the accessibility of generated code.In this paper,we propose UI layers merger(UILM),a vision-based method that can automatically detect and merge fragmented layers into UI components.Our UILM contains the merging area detector(MAD)and a layer merging algorithm.The MAD incorporates the boundary prior knowledge to accurately detect the boundaries of UI components.Then,the layer merging algorithm can search for the associated layers within the components’boundaries and merge them into a whole.We present a dynamic data augmentation approach to boost the performance of MAD.We also construct a large-scale UI dataset for training the MAD and testing the performance of UILM.Experimental results show that the proposed method outperforms the best baseline regarding merging area detection and achieves decent layer merging accuracy.A user study on a real application also confirms the effectiveness of our UILM.
基金The work was supported by the National Natural Sciences Foundation of China grant(No.81272528 and No.31370938)National High Technology Research and Development Program(863 Program,No.2012AA02A302)+1 种基金National Science and Technology Major Projects for'Major New Drugs Innovation and Development'(2014ZX09304311-001-002-004)the Beijing Natural Science Foundation(No.5152022).
文摘Currently,display-based methods are well established and widely used in antibody engineering for affinity maturation and structural stability improvement.We obtained a novel anti-human programmed death 1(PD-1)antibody using computer-aided design and a mammalian cell display technology platform.We used computer-aided modeling and distance geometry methods to predict and assign the key residues that contributed to the binding of human PD-L1 to PD-1.Then,we analyzed the sequence of nivolumab(an anti-human PD-1 antibody,referred to as MIL75 in the article)to determine the template for antibody design and library construction.We identified a series of potential substitutions on the obtained template and constructed a virtual epitope-targeted antibody library based on the physicochemical properties and each possible location of the assigned key residues.The virtual antibody libraries were displayed on the surface of mammalian cells as the antigen-binding fragments of full-length immunoglobulin G.Then,we used flow cytometry and sequencing approaches to sort and screen the candidates.Finally,we obtained a novel anti-human PD-1 antibody named FV78.FV78 competitively recognized the PD-1 epitopes that interacted with MIL75 and possessed an affinity comparable to MIL75.Our results implied that FV78 possessed equivalent bioactivity in vitro and in vivo compared with MIL75,which highlighted the probability and prospect of FV78 becoming a new potential antibody therapy.
基金gratefully acknowledge the Science Foundation of Weifang University(No.2020BS16)the Natural Science Foundation of Shandong Province(No.ZR2019BEM017 and ZR2017MB056)the financial support of the National Natural Science Foundation of China(No.21802104).
文摘Modulating the surface coordination environment of Pt based nanocrystals at the atomic level is of great importance to obtain good electrocatalytic performance.Given the fundamental understandings of surface structure degeneration of Pt based nanocrystals,introducing a weak electronegative element to the surface of Pt-based catalysts is beneficial for suppressing surface passivation and improving hydrogen evolution reaction performance of Pt.Density functional theory results reveal that the energy barrier of water dissociation process can be greatly reduced by using Se element as the surface modifier to replace the O.This hypothesis is further validated by experiments that ultralong Pt_(85)Mo_(15)-Se nanowires were fabricated to suppress the excessive passivation behavior of transition metals of Pt based alloy.The Pt_(85)Mo_(15)-Se nanowires exhibit higher activity with 4.98 times the specific activity and 4.87 times the mass activity of commercial Pt/C,as well as a better stability towards alkaline hydrogen evolution reaction.The deep exploration of X-ray photoelectron spectroscopy and theoretical calculations disclose that Se element could maintain the electron-rich state around the electronic orbit of Pt.This study provides a new insight to advance the fundamental understanding on electrocatalytic materials,which exhibits a promising approach to protect the surface chemical environment of Pt based nanocrystals.
