Dry-hot wind stress causes losses in wheat productivity in major growing regions worldwide,especially winter wheat in the Huang-Huai-Hai Plain of China,and both the occurrence and severity of such events are likely to...Dry-hot wind stress causes losses in wheat productivity in major growing regions worldwide,especially winter wheat in the Huang-Huai-Hai Plain of China,and both the occurrence and severity of such events are likely to increase with global climate change.To investigate the recovery of physiological functions and yield formation using a new noncommercial chemical regulator(NCR)following dry-hot wind stress,we conducted a three-year field experiment(2018-2021)with sprayed treatments of tap water(control),monopotassium phosphate(CKP),NCR at both the jointing and flowering stages(CFS),and NCR only at the jointing stage(FSJ)or flowering stage(FSF).The leaf physiology,biomass accumulation and translocation,grain-filling process,and yield components in winter wheat were assessed.Among the single spraying treatments,the FSJ treatment was beneficial for the accumulation of dry matter before anthesis,as well as larger increases in the maximum grain-filling rate and mean grain-filling rate.The FSF treatment performed better in maintaining a high relative chlorophyll content as indicated by the SPAD value,and a low rate of excised leaf water loss in flag leaves,promoting dry matter accumulation and the contribution to grain after anthesis,prolonging the duration of grain filling,and causing the period until the maximum grain-filling rate reached earlier.The CFS treatment was better than any other treatments in relieving the effects of dry-hot wind.The exogenous NCR treatments significantly increased grain yields by 12.45-18.20% in 2018-2019,8.89-13.82% in 2019-2020,and 8.10-9.00% in 2020-2021.The conventional measure of the CKP treatment only increased grain yield by 6.69% in 2020-2021.The CFS treatment had the greatest mitigating effect on yield loss under dry-hot wind stress,followed by the FSF and FSJ treatments,and the CKP treatment only had a minimal effect.In summary,the CFS treatment could be used as the main chemical control measure for wheat stress resistance and yield stability in areas with a high incidence of dry-hot wind.This treatment can effectively regulate green retention and the water status of leaves,promote dry matter accumulation and efficient translocation,improve the grain-filling process,and ultimately reduce yield losses.展开更多
Background:In rodents,research has revealed a role of liver X receptors(LXR) in controlling lipid homeostasis and regulating the synthesis of polyunsaturated fatty acids(PUFA).Recent data suggest that LXRB is the pred...Background:In rodents,research has revealed a role of liver X receptors(LXR) in controlling lipid homeostasis and regulating the synthesis of polyunsaturated fatty acids(PUFA).Recent data suggest that LXRB is the predominant LXR subtype in ruminant mammary cells,but its role in lipid metabolism is unknown.It was hypothesized that LXRB plays a role in lipid homeostasis via altering the synthesis of PUFA in the ruminant mammary gland.We used overexpression and knockdown of LXRB in goat primary mammary epithelial cells(GMEC) to evaluate abundance of lipogenic enzymes,fatty acid profiles,content of lipid stores and activity of the stearoyl-Co A desaturase(SCD1) promoter.Results:Overexpression of LXRB markedly upregulated the protein abundance of LXRB while incubation with si RNA targeting LXRB markedly decreased abundance of LXRB protein.Overexpression of LXRB plus T0901317(T09,a ligand for LXR) dramatically upregulated SCD1 and elongation of very long chain fatty acid-like fatty acid elongases 5–7(ELOVL 5–7),which are related to PUFA synthesis.Compared with the control,cells overexpressing LXRB and stimulated with T09 had greater concentrations of C16:0,16:1,18:1n7,18:1n9 and C18:2 as well as desaturation and elongation indices of C16:0.Furthermore,LXRB-overexpressing cells incubated with T09 had greater levels of triacylglycerol and cholesterol.Knockdown of LXRB in cells incubated with T09 led to downregulation of genes encoding elongases and desaturases.Knockdown of LXRB attenuated the increase in triacylglycerol and cholesterol that was induced by T09.In cells treated with dimethylsulfoxide,knockdown of LXRB increased the concentration of C16:0 at the expense of C18:0,while a significant decrease in C18:2 was observed in cells incubated with both si LXRB and T09.The abundance of sterol regulatory element binding transcription factor 1 precursor(p SREBP1) and its mature fragment(n SREBP1) was upregulated by T09,but not LXRB overexpression.In the cells cultured with T09,knockdown of LXRB downregulated the abundance for p SREBP1 and n SREBP1.Luciferase reporter assays revealed that the activities of wild type SCD1 promoter or fragment with SREBP1 response element(SRE) mutation were decreased markedly when LXRB was knocked down.Activity of the SCD1 promoter that was induced by T09 was blocked when the SRE mutation was introduced.Conclusion:The current study provides evidence of a physiological link between the LXRB and SREBP1 in the ruminant mammary cell.An important role was revealed for the LXRB-SREBP1 network in the synthesis of PUFA via the regulation of genes encoding elongases and desaturases.Thus,targeting this network might elicit broad effects on lipid homeostasis in ruminant mammary gland.展开更多
Drought stress is one of the most severe environmental constraints to plant growth and crop productivity. Plant growth is greatly affected by drought stress, and plants, to survive,adapt to this stress by invoking dif...Drought stress is one of the most severe environmental constraints to plant growth and crop productivity. Plant growth is greatly affected by drought stress, and plants, to survive,adapt to this stress by invoking different pathways. Piriformospora indica, a root-colonizing endophytic fungus of Sebacinales, promotes plant growth and confers resistance to biotic and abiotic stresses, including drought stress, by affecting the physiological properties of the host plant. The fungus strongly colonizes the roots of maize(Zea mays L.) and promotes shoot and root growth under both normal growth conditions and drought stress. We used polyethylene glycol(PEG-6000) to mimic drought stress and found that root fresh and dry weight, leaf area, SPAD value, and leaf number were increased in P. indica-colonized plants.The antioxidative activities of catalases and superoxide dismutases were upregulated within 24h in the leaves of P. indica-colonized plants. Drought-related genes DREB2A, CBL1,ANAC072, and RD29A were upregulated in drought-stressed leaves of P. indica-colonized plants. Furthermore, after drought treatment, proline content increased, whereas accumulation of malondialdehyde(MDA), an indicator of membrane damage, decreased in P. indica-colonized maize. We conclude that P. indica-mediated plant protection against the detrimental effects of drought may result from enhanced antioxidant enzyme activity,proline accumulation, and expression of drought-related genes and lower membrane damage in maize plants.展开更多
Wheat seed development is an important physiological process of seed maturation and directly affects wheat yield and quality. In this study, we performed dynamic transcriptome microarray analysis of an elite Chinese b...Wheat seed development is an important physiological process of seed maturation and directly affects wheat yield and quality. In this study, we performed dynamic transcriptome microarray analysis of an elite Chinese bread wheat cultivar(Jimai 20) during grain development using the Gene Chip Wheat Genome Array. Grain morphology and scanning electron microscope observations showed that the period of 11–15 days post-anthesis(DPA) was a key stage for the synthesis and accumulation of seed starch. Genome-wide transcriptional profiling and significance analysis of microarrays revealed that the period from 11 to 15 DPA was more important than the 15–20 DPA stage for the synthesis and accumulation of nutritive reserves.Series test of cluster analysis of differential genes revealed five statistically significant gene expression profiles. Gene ontology annotation and enrichment analysis gave further information about differentially expressed genes, and Map Man analysis revealed expression changes within functional groups during seed development. Metabolic pathway network analysis showed that major and minor metabolic pathways regulate one another to ensure regular seed development and nutritive reserve accumulation. We performed gene co-expression network analysis to identify genes that play vital roles in seed development and identified several key genes involved in important metabolic pathways. The transcriptional expression of eight key genes involved in starch and protein synthesis and stress defense was further validated by q RT-PCR. Our results provide new insight into the molecular mechanisms of wheat seed development and the determinants of yield and quality.展开更多
Since the efficiency of photovoltaic(PV) power is closely related to the weather,many PV enterprises install weather instruments to monitor the working state of the PV power system.With the development of the soft mea...Since the efficiency of photovoltaic(PV) power is closely related to the weather,many PV enterprises install weather instruments to monitor the working state of the PV power system.With the development of the soft measurement technology,the instrumental method seems obsolete and involves high cost.This paper proposes a novel method for predicting the types of weather based on the PV power data and partial meteorological data.By this method,the weather types are deduced by data analysis,instead of weather instrument A better fault detection is obtained by using the support vector machines(SVM) and comparing the predicted and the actual weather.The model of the weather prediction is established by a direct SVM for training multiclass predictors.Although SVM is suitable for classification,the classified results depend on the type of the kernel,the parameters of the kernel,and the soft margin coefficient,which are difficult to choose.In this paper,these parameters are optimized by particle swarm optimization(PSO) algorithm in anticipation of good prediction results can be achieved.Prediction results show that this method is feasible and effective.展开更多
Flowering time is an indicator of adaptation in maize and a key trait for selection in breeding.The genetic basis of flowering time in maize,especially in response to plant density,remains unclear.The objective of thi...Flowering time is an indicator of adaptation in maize and a key trait for selection in breeding.The genetic basis of flowering time in maize,especially in response to plant density,remains unclear.The objective of this study was to identify maize quantitative trait loci(QTL)associated with flowering time-related traits that are stably expressed under several plant densities and show additive effects that vary with plant density.Three hundred recombinant inbred lines(RIL)derived from a cross between Ye 478 and Qi 319,together with their parents,were planted at three plant densities(90,000,120,000,and 150,000 plants ha^(-1))in four environments.The five traits investigated were days to tasseling(DTT),days to silking(DTS),days to pollen shed(DTP),interval between anthesis and silking(ASI),and interval between tasseling and anthesis(TAI).A high-resolution bin map was used for QTL mapping.In the RIL population,the DTT,DTS,and DTP values increased with plant density,whereas the ASI and TAI values showed negligible response to plant density.A total of 72 QTL were identified for flowering time-related traits,including 15 stably expressed across environments.Maize flowering time under different densities seems to be regulated by complex pathways rather than by several major genes or an independent pathway.The effects of some stable QTL,especially qDTT8-1 and qDTT10-4,varied with plant density.Fine mapping and cloning of these QTL will shed light on the mechanism of flowering time and assist in breeding earlymaturing maize inbred lines and hybrids.展开更多
The aromatic shrub Lavandula angustifolia produces various volatile terpenoids that serve as resources for essential oils and function in plant-insect communication.To better understand the genetic basis of the terpen...The aromatic shrub Lavandula angustifolia produces various volatile terpenoids that serve as resources for essential oils and function in plant-insect communication.To better understand the genetic basis of the terpenoid diversity in lavender,we present a high-quality reference genome for the Chinese lavender cultivar‘Jingxun 2'using PacBio and Hi-C technologies to anchor the 894.50 Mb genome assembly into 27 pseudochromosomes.In addition to the y triplication event,lavender underwent two rounds of whole-genome duplication(WGD)during the Eocene-Oligocene(29.6 MYA)and Miocene-Pliocene(6.9 MYA)transitions.As a result of tandem duplications and lineage-specific WGDs,gene families related to terpenoid biosynthesis in lavender are substantially expanded compared to those of five other species in Lamiaceae.Many terpenoid biosynthesis transcripts are abundant in glandular trichomes.We further integrated the contents of ecologically functional terpenoids and coexpressed terpenoid biosynthetic genes to construct terpenoid-gene networks.Typical gene clusters,including TPS-TPS,TPS-CYP450,and TPS-BAHD,linked with compounds that primarily function as attractants or repellents,were identified by their similar patterns of change during flower development or in response to methyl jasmonate.Comprehensive analysis of the genetic basis of the production of volatiles in lavender could serve as a foundation for future research into lavender evolution,phytochemistry,and ecology.展开更多
Serendipita indica(formerly known as Piriformospora indica),a root endophytic fungus,exhibits multiple functions in some agricultural,horticultural,and medicinal plant species.We studied colonization of the roots of P...Serendipita indica(formerly known as Piriformospora indica),a root endophytic fungus,exhibits multiple functions in some agricultural,horticultural,and medicinal plant species.We studied colonization of the roots of Platycladus orientalis,a forest tree species,by S.indica to improve the quality of the seedlings in seedbeds and survival rates in sylviculture.At 20 days after inoculation,S.indica colonized the root cortex of P.orientalis seedlings.Root colonization by S.indica significantly increased net CO2 assimilation,light use efficiency,and biomass accumulation by both roots and shoots,whereas it did not affect the biomass allocation between roots and shoots.In addition,the symbiosis significantly increased root total length,surface area,and volume.In view of the two specific traits of S.indica,i.e.,axenic culture and wide colonization in plants,the fungus might be used for improving quality of P.orientalis seedlings and increasing their survival after transplanting.展开更多
During the evolution,plants acquired the ability to synthesize different phenylpropanoid compounds like chlorogenic acid(CGA),which plays vital roles in resistance mechanisms to abiotic stresses.These environmental fa...During the evolution,plants acquired the ability to synthesize different phenylpropanoid compounds like chlorogenic acid(CGA),which plays vital roles in resistance mechanisms to abiotic stresses.These environmental factors,including heavy metal,cold,heat,ultraviolet(UV)light,drought,and salinity affect the plant physiological processes,resulting in massive losses of agriculture production.As plants evolve from green algae to bryophytes,ferns,gymnosperms and angiosperms,phenylpropanoids are produced and accumulated in different tissues,giving the plant the capacity to counteract the harmful effects of the adverse environments.Studies have been performed on the metabolic evolution of rosmarinic acid,flavonoids and lignin,showing that the biosynthesis of phenylpropanoids begins in green algae until the emersion of genes found in angiosperms;however,the evolution of the CGA pathway has not yet been reviewed.We hypothesize that CGA could also be synthesized from algae to angiosperms.In the present review,the evolutionary analysis of CGA pathway and the function of this compound in plant tolerance to abiotic stresses are summarized.Bioinformatics analyzes were carried out on CGA-related genes across 37 plant species and revealed that the metabolic pathway starts in algae and gradually increases until it becomes complete in angiosperms.The key genes exhibited different expression patterns in stress and plant tissues.Interestingly,some genes accumulated rapidly during evolution and were more sensitive to environmental stresses,while others appeared only later in angiosperms.Further studies are needed to better understand the evolution of the CGA metabolic pathway in plants under environmentally stressed conditions.展开更多
After the publication of this article 1,the authors became aware that the legends of Figs.3 and 4 were inverted.The correct version is shown below.In addition,the Lavandula angustifolia‘Jingxun 2’was mistakenly edit...After the publication of this article 1,the authors became aware that the legends of Figs.3 and 4 were inverted.The correct version is shown below.In addition,the Lavandula angustifolia‘Jingxun 2’was mistakenly edited as Lavandula angustifolia“Jingxun 2”.展开更多
The findings of the study indicate that students prefer to engage in the vocabulary learning strategies that would be most appealing to them and that would entail less manipulation of the language. Of the four vocabul...The findings of the study indicate that students prefer to engage in the vocabulary learning strategies that would be most appealing to them and that would entail less manipulation of the language. Of the four vocabulary memorizing strategies cited in the study （rote repetition, structural associations, semantic strategies, and mnemonic keyword techniques）, students apparently tended to favor the second and the third ones, though rote repetition remains appealing to some of them. Mnemonic devices such as keyword method were rather unpopular to most of the students because they would involve the learners in more active performance of the target language.展开更多
The Earth's rotational normal modes depend on Earth model used, including the layer structures,principal inertia moments of different layers and the compliances. This study focuses on providing numerical solution ...The Earth's rotational normal modes depend on Earth model used, including the layer structures,principal inertia moments of different layers and the compliances. This study focuses on providing numerical solution of the rotational normal modes of a triaxial two-layered anelastic Earth model without external forces but with considering the complex forms of compliances and the electromagnetic coupling between the core and mantle. Based on the present knowledge of the Chandler wobble(CW) and Free Core Nutation(FCN), we provide a set of complete compliances which could be used for reference in further investigations. There are eight rotational normal mode solutions, four of which might exist in nature. However, in reality only two of these four solutions correspond to the present motion status of the prograde CW and the retrograde FCN. On one hand, our numerical calculations show that the periods and quality factors(Qs) of CW and FCN are respectively 434.90 and 429.86 mean solar days(d) and 76.56 and 23988.47 under frequency-dependent assumption, and the triaxiality prolongs CW about 0.01 d and has hardly effect on FCN. On the other hand, we analyze the sensibility of compliances and electromagnetic coupling parameter on the periods and Qs of CW and FCN and find the sensitive parameters with respect to them.展开更多
(–)-Epicatechin-3-gallate(ECG),a bioactive polyphenolic compound,has contributed a lot to the health benefits of green tea.Great attention has been focused on(–)-epigallocatechin-3-gallate(EGCG),but limited research...(–)-Epicatechin-3-gallate(ECG),a bioactive polyphenolic compound,has contributed a lot to the health benefits of green tea.Great attention has been focused on(–)-epigallocatechin-3-gallate(EGCG),but limited research has been performed towards ECG.Like EGCG,ECG also possesses various pharmacological and physiological properties,such as mediation of antioxidant activities,anti-inflammation response,regulation of cell proliferation and apoptosis,as well as anticancer properties during angiogenesis,invasion and metastasis stages.Nontoxic ECG has various molecular targets within the cells,including CYP enzymes,phaseⅡdetoxification and antioxidant enzymes,as well as pro-inflammatory mediators.The antineoplastic mechanism contains inhibition of phase 1 CYP enzymes,induction of phaseⅡdetoxification and antioxidant enzymes,high anti-inflammatory efficacy,arrest of cell cycle progression,regulation of apoptosis,as well as mediation of metastasis processes.In particular,the gallate moiety of ECG is critical for mediating inhibitory effects towards cancer cells.Besides regulation of intracellular signaling pathways,ECG also inhibits RNase A and matrix metalloproteinase enzymatic activity via chelating metals(copper and zinc)in cancer cells.This review has summarized recent studies on pharmacological properties of ECG,and discussed corresponding mechanism on modulation of cellular signaling events by ECG,hoping to broaden its multiple usage.展开更多
Fusarium wilt,a disease caused by Fusarium oxysporum f.sp batatas(Fob)is an important disease in sweet potato production.Using endophytic bacteria for biological control of sweet potato diseases is one of the importan...Fusarium wilt,a disease caused by Fusarium oxysporum f.sp batatas(Fob)is an important disease in sweet potato production.Using endophytic bacteria for biological control of sweet potato diseases is one of the important ways.A Bacillus subtilis with antagonistic effect on Fusarium wilt of sweet potato was isolated from soil by confrontation culture.According to the biological characteristics,16S rDNA sequence analysis,and physiological and biochemical analysis,the Bacillus subtilis HAAS01 was named.A pot experiment was conducted for the biological control experiment of strain HAAS01,and the endogenous hormone content,antioxidant enzyme activity,soluble protein content,and related gene expressions of sweet potato plants were detected.The results showed that the HAAS01 strain could promote the production of endogenous hormones and resist the infection of plant diseases together with defensive enzymes and upregulation of related gene expressions.In summary,Bacillus subtilis HAAS01 was effective in controlling Fusarium wilt of sweet potato and has potential for application and development.展开更多
With the global warming and climate change in recent years, heat stress has become one of the major abiotic factors constraining production and productivity of crops in many regions around the world. Although the plan...With the global warming and climate change in recent years, heat stress has become one of the major abiotic factors constraining production and productivity of crops in many regions around the world. Although the plants have developed some adaptive behaviors and avoidance mechanisms against heat stress, they will be hurt under extreme high temperature. Exogenous compounds could enhance plant growth and development, antioxidant enzymes activities, chlorophyll and nutrient contents under stress conditions. Meanwhile, application of exogenous compounds sustains physiological and biochemical process and prevents plants from physiological changes under stress conditions. In this review, effects of heat stress upon crops, and the functions of hormones in plant adaptation to heat stress are simply stated. Then, we intend to appraise how various phytohomrnones that are related to plant adaptation to heat stress. The role of abscisic acid(ABA), salicylic acid(SA) and polyamines(putrescine and spermine) under heat stress conditions are mainly discussed.展开更多
Until now, the calculation of the principal inertia moment of the triaxial three-layered Earth mainly adopts the scaling method. This method assumes that the corresponding principal inertia axes of the layers coincide...Until now, the calculation of the principal inertia moment of the triaxial three-layered Earth mainly adopts the scaling method. This method assumes that the corresponding principal inertia axes of the layers coincide each other, but this is not the case. In this paper, a rigorous tensor transformation rule is adopted to calculate the principal inertia moments(PIMs) of different layers. Appling the new estimated PIMs to the triaxial three-layered Earth rotation theory with considering various couplings, the numerical calculations show that the periods of the Chandler Wobble(CW), Free Core Nutation(FCN), Free Inner Core Nutation(FICN) and Inner Core Wobble(ICW) are respectively 433.0, 430.8, 943.9 and 2735.9 mean solar days, which are well comparable with the corresponding values accepted at present in geoscience community. Better estimates of the PIMs of different layers may provide better constrains on relevant physical parameters of the Earth’s interior.展开更多
Flooding/submergence of rice fields is a severe problem in South and South-East Asia, affecting more than 20 million hectares of rice every year. Submergence creates hypoxic or anoxic condition causing poor germinatio...Flooding/submergence of rice fields is a severe problem in South and South-East Asia, affecting more than 20 million hectares of rice every year. Submergence creates hypoxic or anoxic condition causing poor germination, seedling establishment,and enormous yield loss. Standing water in the field from weeks to months also leads to significant yield losses when large part of aerial tissues is under water. For flash flooding, a rice variety FR1A3 with tolerant gene(SUB1A) was identified. SNORKEL1 and SNORKEL2 have been identified for their ability to survive deep-water flooding by rapid elongation. Submergence stress has also been reported to adversely affect cell division and damage cellular and organelle membranes. Research on antioxidative enzymes response and genes that confer tolerance to prolonged flooding is in progress. Here we review the different anoxia responsive genes and the potential involvement of antioxidative enzymes, such as superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase, which occur in cells of rice plant exposed to submergence stress.展开更多
The four artificial lakes in Guangzhou(Liwan Lake,Liuhua Lake,Lu Lake,Dongshan Lake)have maintained a benign relationship with the city for the symbiosis of human,nature and society since the end of the 1950s.Taking t...The four artificial lakes in Guangzhou(Liwan Lake,Liuhua Lake,Lu Lake,Dongshan Lake)have maintained a benign relationship with the city for the symbiosis of human,nature and society since the end of the 1950s.Taking the four artificial lakes in Guangzhou as the research object,reviewing the construction process of the four artificial lakes in Guangzhou,and combing the ecological practice experience of the four artificial lakes.It is concluded that siting selection suitable for urban geographic conditions,considering the construction of artificial lakes in urban water systems,designing incorporating cultural,constructing and renovating the park combined with urban development and establishing lake-park symbiosis are the internal cause for the benign interoperability and coordinated development of the four artificial lakes and cities.In order to provide reference for the construction of urban artificial lakes in Guangzhou and the urban ecological environment construction of Guangdong,Hong Kong and Macao Dawan District.展开更多
基金supported by the National Key Research and Development Program of China(2019YFE0197100)the earmarked fund for China Agriculture Research System(CARS-03-01A)the Agricultural Science and Technology Innovation Project of the Chinese Academy of Agricultural Sciences。
文摘Dry-hot wind stress causes losses in wheat productivity in major growing regions worldwide,especially winter wheat in the Huang-Huai-Hai Plain of China,and both the occurrence and severity of such events are likely to increase with global climate change.To investigate the recovery of physiological functions and yield formation using a new noncommercial chemical regulator(NCR)following dry-hot wind stress,we conducted a three-year field experiment(2018-2021)with sprayed treatments of tap water(control),monopotassium phosphate(CKP),NCR at both the jointing and flowering stages(CFS),and NCR only at the jointing stage(FSJ)or flowering stage(FSF).The leaf physiology,biomass accumulation and translocation,grain-filling process,and yield components in winter wheat were assessed.Among the single spraying treatments,the FSJ treatment was beneficial for the accumulation of dry matter before anthesis,as well as larger increases in the maximum grain-filling rate and mean grain-filling rate.The FSF treatment performed better in maintaining a high relative chlorophyll content as indicated by the SPAD value,and a low rate of excised leaf water loss in flag leaves,promoting dry matter accumulation and the contribution to grain after anthesis,prolonging the duration of grain filling,and causing the period until the maximum grain-filling rate reached earlier.The CFS treatment was better than any other treatments in relieving the effects of dry-hot wind.The exogenous NCR treatments significantly increased grain yields by 12.45-18.20% in 2018-2019,8.89-13.82% in 2019-2020,and 8.10-9.00% in 2020-2021.The conventional measure of the CKP treatment only increased grain yield by 6.69% in 2020-2021.The CFS treatment had the greatest mitigating effect on yield loss under dry-hot wind stress,followed by the FSF and FSJ treatments,and the CKP treatment only had a minimal effect.In summary,the CFS treatment could be used as the main chemical control measure for wheat stress resistance and yield stability in areas with a high incidence of dry-hot wind.This treatment can effectively regulate green retention and the water status of leaves,promote dry matter accumulation and efficient translocation,improve the grain-filling process,and ultimately reduce yield losses.
基金supported by the National Natural Science Foundation of China(31702090)Key R&D program of Zhejiang Province(2022C04017)+1 种基金Zhejiang Provincial Major Science and Technology Projects on Agricultural New Varieties Selection and Breeding(2021C02068-6)Opening fund in Key Laboratory of Molecular Animal Nutrition(Zhejiang University,KLMAN202103).
文摘Background:In rodents,research has revealed a role of liver X receptors(LXR) in controlling lipid homeostasis and regulating the synthesis of polyunsaturated fatty acids(PUFA).Recent data suggest that LXRB is the predominant LXR subtype in ruminant mammary cells,but its role in lipid metabolism is unknown.It was hypothesized that LXRB plays a role in lipid homeostasis via altering the synthesis of PUFA in the ruminant mammary gland.We used overexpression and knockdown of LXRB in goat primary mammary epithelial cells(GMEC) to evaluate abundance of lipogenic enzymes,fatty acid profiles,content of lipid stores and activity of the stearoyl-Co A desaturase(SCD1) promoter.Results:Overexpression of LXRB markedly upregulated the protein abundance of LXRB while incubation with si RNA targeting LXRB markedly decreased abundance of LXRB protein.Overexpression of LXRB plus T0901317(T09,a ligand for LXR) dramatically upregulated SCD1 and elongation of very long chain fatty acid-like fatty acid elongases 5–7(ELOVL 5–7),which are related to PUFA synthesis.Compared with the control,cells overexpressing LXRB and stimulated with T09 had greater concentrations of C16:0,16:1,18:1n7,18:1n9 and C18:2 as well as desaturation and elongation indices of C16:0.Furthermore,LXRB-overexpressing cells incubated with T09 had greater levels of triacylglycerol and cholesterol.Knockdown of LXRB in cells incubated with T09 led to downregulation of genes encoding elongases and desaturases.Knockdown of LXRB attenuated the increase in triacylglycerol and cholesterol that was induced by T09.In cells treated with dimethylsulfoxide,knockdown of LXRB increased the concentration of C16:0 at the expense of C18:0,while a significant decrease in C18:2 was observed in cells incubated with both si LXRB and T09.The abundance of sterol regulatory element binding transcription factor 1 precursor(p SREBP1) and its mature fragment(n SREBP1) was upregulated by T09,but not LXRB overexpression.In the cells cultured with T09,knockdown of LXRB downregulated the abundance for p SREBP1 and n SREBP1.Luciferase reporter assays revealed that the activities of wild type SCD1 promoter or fragment with SREBP1 response element(SRE) mutation were decreased markedly when LXRB was knocked down.Activity of the SCD1 promoter that was induced by T09 was blocked when the SRE mutation was introduced.Conclusion:The current study provides evidence of a physiological link between the LXRB and SREBP1 in the ruminant mammary cell.An important role was revealed for the LXRB-SREBP1 network in the synthesis of PUFA via the regulation of genes encoding elongases and desaturases.Thus,targeting this network might elicit broad effects on lipid homeostasis in ruminant mammary gland.
基金supported by the National Natural Science Foundation of China(No.31471496)
文摘Drought stress is one of the most severe environmental constraints to plant growth and crop productivity. Plant growth is greatly affected by drought stress, and plants, to survive,adapt to this stress by invoking different pathways. Piriformospora indica, a root-colonizing endophytic fungus of Sebacinales, promotes plant growth and confers resistance to biotic and abiotic stresses, including drought stress, by affecting the physiological properties of the host plant. The fungus strongly colonizes the roots of maize(Zea mays L.) and promotes shoot and root growth under both normal growth conditions and drought stress. We used polyethylene glycol(PEG-6000) to mimic drought stress and found that root fresh and dry weight, leaf area, SPAD value, and leaf number were increased in P. indica-colonized plants.The antioxidative activities of catalases and superoxide dismutases were upregulated within 24h in the leaves of P. indica-colonized plants. Drought-related genes DREB2A, CBL1,ANAC072, and RD29A were upregulated in drought-stressed leaves of P. indica-colonized plants. Furthermore, after drought treatment, proline content increased, whereas accumulation of malondialdehyde(MDA), an indicator of membrane damage, decreased in P. indica-colonized maize. We conclude that P. indica-mediated plant protection against the detrimental effects of drought may result from enhanced antioxidant enzyme activity,proline accumulation, and expression of drought-related genes and lower membrane damage in maize plants.
基金financially supported by grants from the National Natural Science Foundation of China(31471485)Natural Science Foundation of Beijing Citythe Key Developmental Project of Science and Technology from Beijing Municipal Commission of Education(KZ201410028031)
文摘Wheat seed development is an important physiological process of seed maturation and directly affects wheat yield and quality. In this study, we performed dynamic transcriptome microarray analysis of an elite Chinese bread wheat cultivar(Jimai 20) during grain development using the Gene Chip Wheat Genome Array. Grain morphology and scanning electron microscope observations showed that the period of 11–15 days post-anthesis(DPA) was a key stage for the synthesis and accumulation of seed starch. Genome-wide transcriptional profiling and significance analysis of microarrays revealed that the period from 11 to 15 DPA was more important than the 15–20 DPA stage for the synthesis and accumulation of nutritive reserves.Series test of cluster analysis of differential genes revealed five statistically significant gene expression profiles. Gene ontology annotation and enrichment analysis gave further information about differentially expressed genes, and Map Man analysis revealed expression changes within functional groups during seed development. Metabolic pathway network analysis showed that major and minor metabolic pathways regulate one another to ensure regular seed development and nutritive reserve accumulation. We performed gene co-expression network analysis to identify genes that play vital roles in seed development and identified several key genes involved in important metabolic pathways. The transcriptional expression of eight key genes involved in starch and protein synthesis and stress defense was further validated by q RT-PCR. Our results provide new insight into the molecular mechanisms of wheat seed development and the determinants of yield and quality.
基金supported by the National Natural Science Foundation of China(61433004,61473069)IAPI Fundamental Research Funds(2013ZCX14)+1 种基金supported by the Development Project of Key Laboratory of Liaoning Provincethe Enterprise Postdoctoral Fund Projects of Liaoning Province
文摘Since the efficiency of photovoltaic(PV) power is closely related to the weather,many PV enterprises install weather instruments to monitor the working state of the PV power system.With the development of the soft measurement technology,the instrumental method seems obsolete and involves high cost.This paper proposes a novel method for predicting the types of weather based on the PV power data and partial meteorological data.By this method,the weather types are deduced by data analysis,instead of weather instrument A better fault detection is obtained by using the support vector machines(SVM) and comparing the predicted and the actual weather.The model of the weather prediction is established by a direct SVM for training multiclass predictors.Although SVM is suitable for classification,the classified results depend on the type of the kernel,the parameters of the kernel,and the soft margin coefficient,which are difficult to choose.In this paper,these parameters are optimized by particle swarm optimization(PSO) algorithm in anticipation of good prediction results can be achieved.Prediction results show that this method is feasible and effective.
基金This study was supported by Hebei Province Special Postdoctoral Financial Assistance(B2017003030)the Youth Innovation Fund of the Institute of Cereal and Oil Crops,Hebei Academy of Agriculture and Forestry Sciences(LYS2017001)the Hebei Financial Special Project:Construction of Talents Team for Agricultural Science Technical Innovation,and the China Agriculture Research System(CARS-02).
文摘Flowering time is an indicator of adaptation in maize and a key trait for selection in breeding.The genetic basis of flowering time in maize,especially in response to plant density,remains unclear.The objective of this study was to identify maize quantitative trait loci(QTL)associated with flowering time-related traits that are stably expressed under several plant densities and show additive effects that vary with plant density.Three hundred recombinant inbred lines(RIL)derived from a cross between Ye 478 and Qi 319,together with their parents,were planted at three plant densities(90,000,120,000,and 150,000 plants ha^(-1))in four environments.The five traits investigated were days to tasseling(DTT),days to silking(DTS),days to pollen shed(DTP),interval between anthesis and silking(ASI),and interval between tasseling and anthesis(TAI).A high-resolution bin map was used for QTL mapping.In the RIL population,the DTT,DTS,and DTP values increased with plant density,whereas the ASI and TAI values showed negligible response to plant density.A total of 72 QTL were identified for flowering time-related traits,including 15 stably expressed across environments.Maize flowering time under different densities seems to be regulated by complex pathways rather than by several major genes or an independent pathway.The effects of some stable QTL,especially qDTT8-1 and qDTT10-4,varied with plant density.Fine mapping and cloning of these QTL will shed light on the mechanism of flowering time and assist in breeding earlymaturing maize inbred lines and hybrids.
基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA23080603)the National Natural Science Foundation of China(Grant No.31701956)。
文摘The aromatic shrub Lavandula angustifolia produces various volatile terpenoids that serve as resources for essential oils and function in plant-insect communication.To better understand the genetic basis of the terpenoid diversity in lavender,we present a high-quality reference genome for the Chinese lavender cultivar‘Jingxun 2'using PacBio and Hi-C technologies to anchor the 894.50 Mb genome assembly into 27 pseudochromosomes.In addition to the y triplication event,lavender underwent two rounds of whole-genome duplication(WGD)during the Eocene-Oligocene(29.6 MYA)and Miocene-Pliocene(6.9 MYA)transitions.As a result of tandem duplications and lineage-specific WGDs,gene families related to terpenoid biosynthesis in lavender are substantially expanded compared to those of five other species in Lamiaceae.Many terpenoid biosynthesis transcripts are abundant in glandular trichomes.We further integrated the contents of ecologically functional terpenoids and coexpressed terpenoid biosynthetic genes to construct terpenoid-gene networks.Typical gene clusters,including TPS-TPS,TPS-CYP450,and TPS-BAHD,linked with compounds that primarily function as attractants or repellents,were identified by their similar patterns of change during flower development or in response to methyl jasmonate.Comprehensive analysis of the genetic basis of the production of volatiles in lavender could serve as a foundation for future research into lavender evolution,phytochemistry,and ecology.
基金funded by National Nature Science Foundation of China(31471496)
文摘Serendipita indica(formerly known as Piriformospora indica),a root endophytic fungus,exhibits multiple functions in some agricultural,horticultural,and medicinal plant species.We studied colonization of the roots of Platycladus orientalis,a forest tree species,by S.indica to improve the quality of the seedlings in seedbeds and survival rates in sylviculture.At 20 days after inoculation,S.indica colonized the root cortex of P.orientalis seedlings.Root colonization by S.indica significantly increased net CO2 assimilation,light use efficiency,and biomass accumulation by both roots and shoots,whereas it did not affect the biomass allocation between roots and shoots.In addition,the symbiosis significantly increased root total length,surface area,and volume.In view of the two specific traits of S.indica,i.e.,axenic culture and wide colonization in plants,the fungus might be used for improving quality of P.orientalis seedlings and increasing their survival after transplanting.
基金National Key R&D Program of China(2019YFD1001300,2019YFD1001305)Science and Technology Development Plan Project of Jingzhou City,Hubei Province,China(2018-37)+1 种基金Characteristic Discipline of Hubei Academy of Agricultural Sciences(2015TSXK06)Science and Technology Innovation Center of Hubei Academy of Agricultural Sciences(2007-620-001-03).
文摘During the evolution,plants acquired the ability to synthesize different phenylpropanoid compounds like chlorogenic acid(CGA),which plays vital roles in resistance mechanisms to abiotic stresses.These environmental factors,including heavy metal,cold,heat,ultraviolet(UV)light,drought,and salinity affect the plant physiological processes,resulting in massive losses of agriculture production.As plants evolve from green algae to bryophytes,ferns,gymnosperms and angiosperms,phenylpropanoids are produced and accumulated in different tissues,giving the plant the capacity to counteract the harmful effects of the adverse environments.Studies have been performed on the metabolic evolution of rosmarinic acid,flavonoids and lignin,showing that the biosynthesis of phenylpropanoids begins in green algae until the emersion of genes found in angiosperms;however,the evolution of the CGA pathway has not yet been reviewed.We hypothesize that CGA could also be synthesized from algae to angiosperms.In the present review,the evolutionary analysis of CGA pathway and the function of this compound in plant tolerance to abiotic stresses are summarized.Bioinformatics analyzes were carried out on CGA-related genes across 37 plant species and revealed that the metabolic pathway starts in algae and gradually increases until it becomes complete in angiosperms.The key genes exhibited different expression patterns in stress and plant tissues.Interestingly,some genes accumulated rapidly during evolution and were more sensitive to environmental stresses,while others appeared only later in angiosperms.Further studies are needed to better understand the evolution of the CGA metabolic pathway in plants under environmentally stressed conditions.
文摘After the publication of this article 1,the authors became aware that the legends of Figs.3 and 4 were inverted.The correct version is shown below.In addition,the Lavandula angustifolia‘Jingxun 2’was mistakenly edited as Lavandula angustifolia“Jingxun 2”.
文摘The findings of the study indicate that students prefer to engage in the vocabulary learning strategies that would be most appealing to them and that would entail less manipulation of the language. Of the four vocabulary memorizing strategies cited in the study （rote repetition, structural associations, semantic strategies, and mnemonic keyword techniques）, students apparently tended to favor the second and the third ones, though rote repetition remains appealing to some of them. Mnemonic devices such as keyword method were rather unpopular to most of the students because they would involve the learners in more active performance of the target language.
基金supported by the NSFC (grant Nos. 41631072, 41721003, 41874023, 41574007, and 41429401)the Discipline Innovative Engineering Plan of Modern Geodesy and Geodynamics (grant No. B17033)the DAAD Thematic Network Project (grant No. 57173947)
文摘The Earth's rotational normal modes depend on Earth model used, including the layer structures,principal inertia moments of different layers and the compliances. This study focuses on providing numerical solution of the rotational normal modes of a triaxial two-layered anelastic Earth model without external forces but with considering the complex forms of compliances and the electromagnetic coupling between the core and mantle. Based on the present knowledge of the Chandler wobble(CW) and Free Core Nutation(FCN), we provide a set of complete compliances which could be used for reference in further investigations. There are eight rotational normal mode solutions, four of which might exist in nature. However, in reality only two of these four solutions correspond to the present motion status of the prograde CW and the retrograde FCN. On one hand, our numerical calculations show that the periods and quality factors(Qs) of CW and FCN are respectively 434.90 and 429.86 mean solar days(d) and 76.56 and 23988.47 under frequency-dependent assumption, and the triaxiality prolongs CW about 0.01 d and has hardly effect on FCN. On the other hand, we analyze the sensibility of compliances and electromagnetic coupling parameter on the periods and Qs of CW and FCN and find the sensitive parameters with respect to them.
基金funded by Hubei Science and Technology Plan Key Project(G2019ABA100)Open fund of Hubei Key Laboratory of Economic Forest Germplasm Improvement and Resources Comprehensive Utilization(201932103)fund from Assessment and Comprehensive Utilization of Characteristic Biological resources in Dabie Mountains(4022019006)。
文摘(–)-Epicatechin-3-gallate(ECG),a bioactive polyphenolic compound,has contributed a lot to the health benefits of green tea.Great attention has been focused on(–)-epigallocatechin-3-gallate(EGCG),but limited research has been performed towards ECG.Like EGCG,ECG also possesses various pharmacological and physiological properties,such as mediation of antioxidant activities,anti-inflammation response,regulation of cell proliferation and apoptosis,as well as anticancer properties during angiogenesis,invasion and metastasis stages.Nontoxic ECG has various molecular targets within the cells,including CYP enzymes,phaseⅡdetoxification and antioxidant enzymes,as well as pro-inflammatory mediators.The antineoplastic mechanism contains inhibition of phase 1 CYP enzymes,induction of phaseⅡdetoxification and antioxidant enzymes,high anti-inflammatory efficacy,arrest of cell cycle progression,regulation of apoptosis,as well as mediation of metastasis processes.In particular,the gallate moiety of ECG is critical for mediating inhibitory effects towards cancer cells.Besides regulation of intracellular signaling pathways,ECG also inhibits RNase A and matrix metalloproteinase enzymatic activity via chelating metals(copper and zinc)in cancer cells.This review has summarized recent studies on pharmacological properties of ECG,and discussed corresponding mechanism on modulation of cellular signaling events by ECG,hoping to broaden its multiple usage.
基金the National Key R&D Program of China,2019YFD1001300 and 2019YFD1001305China Agriculture Research System of MOF and MARA,China.
文摘Fusarium wilt,a disease caused by Fusarium oxysporum f.sp batatas(Fob)is an important disease in sweet potato production.Using endophytic bacteria for biological control of sweet potato diseases is one of the important ways.A Bacillus subtilis with antagonistic effect on Fusarium wilt of sweet potato was isolated from soil by confrontation culture.According to the biological characteristics,16S rDNA sequence analysis,and physiological and biochemical analysis,the Bacillus subtilis HAAS01 was named.A pot experiment was conducted for the biological control experiment of strain HAAS01,and the endogenous hormone content,antioxidant enzyme activity,soluble protein content,and related gene expressions of sweet potato plants were detected.The results showed that the HAAS01 strain could promote the production of endogenous hormones and resist the infection of plant diseases together with defensive enzymes and upregulation of related gene expressions.In summary,Bacillus subtilis HAAS01 was effective in controlling Fusarium wilt of sweet potato and has potential for application and development.
基金Supported by Natural Science Foundation of Hubei Province(2013CFA011)
文摘With the global warming and climate change in recent years, heat stress has become one of the major abiotic factors constraining production and productivity of crops in many regions around the world. Although the plants have developed some adaptive behaviors and avoidance mechanisms against heat stress, they will be hurt under extreme high temperature. Exogenous compounds could enhance plant growth and development, antioxidant enzymes activities, chlorophyll and nutrient contents under stress conditions. Meanwhile, application of exogenous compounds sustains physiological and biochemical process and prevents plants from physiological changes under stress conditions. In this review, effects of heat stress upon crops, and the functions of hormones in plant adaptation to heat stress are simply stated. Then, we intend to appraise how various phytohomrnones that are related to plant adaptation to heat stress. The role of abscisic acid(ABA), salicylic acid(SA) and polyamines(putrescine and spermine) under heat stress conditions are mainly discussed.
基金supported by NSFCs(grant Nos.41721003,41631072,41874023,41804012,41429401,41574007)
文摘Until now, the calculation of the principal inertia moment of the triaxial three-layered Earth mainly adopts the scaling method. This method assumes that the corresponding principal inertia axes of the layers coincide each other, but this is not the case. In this paper, a rigorous tensor transformation rule is adopted to calculate the principal inertia moments(PIMs) of different layers. Appling the new estimated PIMs to the triaxial three-layered Earth rotation theory with considering various couplings, the numerical calculations show that the periods of the Chandler Wobble(CW), Free Core Nutation(FCN), Free Inner Core Nutation(FICN) and Inner Core Wobble(ICW) are respectively 433.0, 430.8, 943.9 and 2735.9 mean solar days, which are well comparable with the corresponding values accepted at present in geoscience community. Better estimates of the PIMs of different layers may provide better constrains on relevant physical parameters of the Earth’s interior.
文摘Flooding/submergence of rice fields is a severe problem in South and South-East Asia, affecting more than 20 million hectares of rice every year. Submergence creates hypoxic or anoxic condition causing poor germination, seedling establishment,and enormous yield loss. Standing water in the field from weeks to months also leads to significant yield losses when large part of aerial tissues is under water. For flash flooding, a rice variety FR1A3 with tolerant gene(SUB1A) was identified. SNORKEL1 and SNORKEL2 have been identified for their ability to survive deep-water flooding by rapid elongation. Submergence stress has also been reported to adversely affect cell division and damage cellular and organelle membranes. Research on antioxidative enzymes response and genes that confer tolerance to prolonged flooding is in progress. Here we review the different anoxia responsive genes and the potential involvement of antioxidative enzymes, such as superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase, which occur in cells of rice plant exposed to submergence stress.
文摘The four artificial lakes in Guangzhou(Liwan Lake,Liuhua Lake,Lu Lake,Dongshan Lake)have maintained a benign relationship with the city for the symbiosis of human,nature and society since the end of the 1950s.Taking the four artificial lakes in Guangzhou as the research object,reviewing the construction process of the four artificial lakes in Guangzhou,and combing the ecological practice experience of the four artificial lakes.It is concluded that siting selection suitable for urban geographic conditions,considering the construction of artificial lakes in urban water systems,designing incorporating cultural,constructing and renovating the park combined with urban development and establishing lake-park symbiosis are the internal cause for the benign interoperability and coordinated development of the four artificial lakes and cities.In order to provide reference for the construction of urban artificial lakes in Guangzhou and the urban ecological environment construction of Guangdong,Hong Kong and Macao Dawan District.
