Potassium （K^＋） is an essential macronutrient for all living organisms and large amounts are required for plant growth and development. In many regions of Asia K＋-fertilization has been neglected and soils have be...Potassium （K^＋） is an essential macronutrient for all living organisms and large amounts are required for plant growth and development. In many regions of Asia K＋-fertilization has been neglected and soils have become K＋-depleted. K＋- deficiency in the field diminishes not only crop production but also leads to environmental problems due to inefficient usage and leaching of nitrate. Consequences of K^＋-deficiency on crop production range from decreased biomass, nutritional quality and taste of the crops to inferior harvest and storage properties, as well as increased susceptibility to disease. Effects of K^＋-deficiency on plant physiology include decreased photosynthetic rate, impaired tissue allocation of sugars and amino acids, decreased protein synthesis.展开更多
Plant-parasitic nematodes caused severe yield loss in major crops all over the world.The most wild-used strategies to combat the nematodes is the chamical nematicides,but the overuse of synthetic nematicides threaten ...Plant-parasitic nematodes caused severe yield loss in major crops all over the world.The most wild-used strategies to combat the nematodes is the chamical nematicides,but the overuse of synthetic nematicides threaten sustainable agriculture development.Other strategies,like resistance cultivars and crop rotation,have limited efficiency.Thus,the utilization of molecular biotechnology like RNA interference(RNAi)would be one of the alternative ways to enhance plant resistance against nematodes.RNAi has already used as a tool for gene functional analysis in a wide range of species,especially in the non-parasitic nematode,Caenorhabtidis elegans.In plant-parasitic nematodes,RNAi is induced by soaking nematodes with double strand RNA(dsRNA)solution mixed with neurostimulants,which is called in vitro RNAi delivery method.In another way around,in planta RNAi method,which is Host-mediated RNAi approach also showed a great success in conferring the resistance against root-knock nematodes.Two main advantages of RNAi-based transgenics are RNAi technology do not produce any functional foreign proteins and it target organisms in a sequence-specific way.Even though the development of RNAi-based transgenics against plant-parasitic nematodes is still in the initial phase,it offers the prospect into a novel nematode control strategy in the future.展开更多
The dry-extract system for (near) infrared (DESIR) technique was implemented using reflectance near-infrared spec-troscopy in context of detection of contact pesticide residues on fruit. Based on chemical structure, s...The dry-extract system for (near) infrared (DESIR) technique was implemented using reflectance near-infrared spec-troscopy in context of detection of contact pesticide residues on fruit. Based on chemical structure, spectra features and regression statistics for PLSR models, a product containing metiram and pyraclostrobin was chosen from six pesticides for further consideration. Regression models based on spectra of dry extracts of aqueous solutions and either acetone or water washes of contaminated fruit were encouraging (RMSECV of approximately 0.03 - 0.06 mg a.i.). This level of analytical performance would support the use of the technique as a rapid screening tool, with suspect samples then subject to the reference GC-MS analysis method. However, the PLSR model performance was poor across populations of fruit, suggesting that matrix changes in the solvent wash between sets of fruit is problematic. Further work is required to establish whether sufficient variation can be built into a calibration set to overcome this issue, without degrading model performance to the point where it loses practical application.展开更多
Ganoderma lucidum is a wildly used medicinal mushroom and has been used in East Asia because of its health-benefit effects. G. lucidum contains various compounds with different biological activities, which include ant...Ganoderma lucidum is a wildly used medicinal mushroom and has been used in East Asia because of its health-benefit effects. G. lucidum contains various compounds with different biological activities, which include anti-tumour, anti-viral, and anti-malaria effect. Ganoderic acid (GA) is a triterpenoid from G. lucidum. The biosynthesis of GA in G. lucidum is induced by stressors including various elicitors or signaling molecules, and artificially placing elicitors would enhance GA production. In this paper, bioactivities and potential applications of GAs would be focused, and the elicitation strategies for GA production are also highlighted based on the fundamental role of ROS, JA, Ca2+ and NO, which would shed light to developing a novel approach to manipulating the biosynthesis of GA in the future.展开更多
Our attitude towards mineral nitrogen (N) fertilizers is ambivalent. N fertilizers have on one hand increased our supply of food, feed and other bio-based raw materials tremendously and also improved the use efficienc...Our attitude towards mineral nitrogen (N) fertilizers is ambivalent. N fertilizers have on one hand increased our supply of food, feed and other bio-based raw materials tremendously and also improved the use efficiency of land and labor, but have on the other hand a negative impact on the quality of the environment and contributed to the depletion of fossil fuel reserves. This awareness has resulted in strong pleas to spend much more attention to the recycling of N containing downstream “wastes”. It is, however, naive to assume that even perfect recycling suffices to offer the same number of people the same diet without inputs of “new” N, as inevitable losses of N make compensations indispensable. “New” N can be derived from either biological N fixation (“legumes”) or from industrially fixed N (“fertilizer”). The existing literature provides no evidence that the use of N fertilizers is per se unsustainable, as these fertilizers can also be made from renewable forms of energy. Besides, soil health and human health appear sensitive for the dosage but not for the form of N. It is yet imperative to reduce the input of “new” N as much as possible, so as to minimize adverse environmental effects. Measures to this end are a more precise assessment of crop N requirements, a better timing and positioning of N inputs, and any measure supporting the acceptance of “wastes” by farmers. The present paper elaborates the above aspects.展开更多
Adequate dietary zinc intake remains a public health challenge in China.Also,there is a lack of information on the relationship between Zn intake and food consumption patterns across provinces and over time.In this st...Adequate dietary zinc intake remains a public health challenge in China.Also,there is a lack of information on the relationship between Zn intake and food consumption patterns across provinces and over time.In this study,data from the China Health and Nutrition Survey 2004-2011(21,266 individuals)was used to explore associations between dietary Zn intake and sociodemographic factors.Zn intake per person declined from 11.1 mg·d^(-1)in 2004 to 9.89 mg·d^(-1)in 2011,with reduction in cereal consumption the greatest contributor to this.However,the reduction resulting from the lower cereal consumption was only partly compensated by an increase in consumption of Zn-rich foods.The percentage of the study population with inadequate Zn intake increased from 23% in 2004 to 37% in 2011.While Zn intake was positively associated with income levels in each survey year,the time trend for all income levels was a gradually reducing Zn intake.In all years,males had an average higher dietary Zn intake,whereas no significant difference was found between living areas.In conclusion,this study shows that dietary Zn inadequacy was high and has increased over the studied period.Remediation could be sought by shifting dietary patterns toward more Zn-dense food or by enhancing Zn concentration through biofortification.展开更多
Thellungiella salsuginea （halophila） is a close relative of Arabidopsis thaliana but, unlike A. thaliana, it grows well in extreme conditions of cold, salt, and drought as well as nitrogen limitation. Over the last ...Thellungiella salsuginea （halophila） is a close relative of Arabidopsis thaliana but, unlike A. thaliana, it grows well in extreme conditions of cold, salt, and drought as well as nitrogen limitation. Over the last decade, many laboratories have started to use Thellungiella to investigate the physiological, metabolic, and molecular mechanisms of abiotic stress tolerance in plants, and new knowledge has been gained in particular with respect to ion transport and gene expression. The advantage of Thellungiella over other extremophile model plants is that it can be directly compared with Arabidopsis, and therefore generate information on both essential and critical components of stress tolerance. Thellungiella research is supported by a growing body of technical resources comprising physiological and molecular protocols, ecotype collections, expressed sequence tags, cDNA-libraries, microarrays, and a pending genome sequence. This review summarizes the current state of knowledge on Thellungiella and re-evaluates its usefulness as a model for research into plant stress tolerance.展开更多
The phototropins phot1 and phot2 are plant blue-light receptors that mediate phototropism, chloroplast movements, stomatal opening, leaf expansion, the rapid Inhibition of hypocotyl growth in etiolated seedlings, and ...The phototropins phot1 and phot2 are plant blue-light receptors that mediate phototropism, chloroplast movements, stomatal opening, leaf expansion, the rapid Inhibition of hypocotyl growth in etiolated seedlings, and possibly solar tracking by leaves in those species in which It occurs. The phototroplns are plasma membrane-associated hydrophilic proteins with two chromophore domains （designated LOV1 and LOV2 for their resemblance to domains In other signaling proteins that detect light, oxygen, or voltage） in their Nterminal half and a classic serine/threonlne kinase domain in their C-terminal half. Both chromophore domains bind flavin mononucleotide （FMN） and both undergo light-activated formation of a covalent bond between a nearby cystelne and the C（4a） carbon of the FMN to form the signaling state. LOV2-cystelnyl adduct formation leads to the release downstream of a tightly bound amphlpathlc α-helix, a step required for activation of the klnase function. This cysteinyl adduct then slowly decays over a matter of seconds or minutes to return the photoreceptor chromophore modules to their ground state. Functional LOV2 is required for light-activated phosphorylation and for various blue-light responses mediated by the phototroplns. The function of LOV1 is still unknown, although It may serve to modulate the signal generated by LOV2. The LOV domain Is an ancient chromophore module found In a wide range of otherwise unrelated proteins In fungi and prokaryotes, the latter Including cyanobacterla, eubacterla, and archaea. Further general reviews on the phototropins are those by Celaya and Liscum （2005） and Christie and Briggs （2005）.展开更多
Mycotoxins are the most frequently occurring natural contaminant in food and feed.Their occurrence in crops and animal feed represents an enormous challenge,particularly for livestock farmers in terms of increased pro...Mycotoxins are the most frequently occurring natural contaminant in food and feed.Their occurrence in crops and animal feed represents an enormous challenge,particularly for livestock farmers in terms of increased production costs,reduced animal performance and profitability.This study investigates the scale of emerging mycotoxins contamination of crops and animal feeds globally,and evaluates their impacts on the health and performance of livestock,especially when they co-occur alongside regulated mycotoxins.Emerging mycotoxins including nivalenol,enniatins,beauvericin,diacetoxyscirpenol,fusaric acid,patulin,moniliformin and sterigmatocystin were found to be the most prevalent contaminants of cereals and other feed commodities worldwide.The pooled mean levels for beauvericin,nivalenol,enniatins,moniliformin,sterigmatocystin,diacetoxyscirpenol,fusaric acid,and patulin were 386,421,7,854,204,136,126,370 and 138 mg/kg,respectively.In terms of toxicity,co-occurrence of emerging mycotoxins with each other and also with regulated mycotoxins profoundly impacts livestock performance,even at low levels.Therefore,there is a need for cumulative risk assessments to evaluate the health risks associated with simultaneous exposure to emerging and regulated mycotoxins and also to develop effective mitigation strategies.展开更多
Black soldier fly larvae(Hermetia illucens)receive growing interest as a potential alternative animal feed source.These insects may be exposed to insecticide residues in the rearing substrate.This study aimed to inves...Black soldier fly larvae(Hermetia illucens)receive growing interest as a potential alternative animal feed source.These insects may be exposed to insecticide residues in the rearing substrate.This study aimed to investigate the effects of six different pyrethroid and organophosphate insecticides on this insect species'performance.The toxicity of two"model"substances for each of these classes(cypermethrin;pirimiphosmethyl)was quantified,with and without the synergist piperonyl butoxide(PBO).Critical effect doses corresponding to 10%yield(CED10)for cypermethrin(0.4 mg/kg)and pirimiphos-methyl(4.8 mg/kg)were determined.The addition of PBO to cypermethrin enhanced its relative potency with a factor 2.6.These data were compared against the relative toxicity of two analogue substances in each class(permethrin,deltamethrin;chlorpyrifosmethyl,malathion).Results suggest that exposure to concentrations complying with legal limits can cause significant reductions in yield.Exposure to multiple substances at lower concentrations resulted in negative additive and synergistic effects.Of the tested substances,deltamethrin was most toxic,causing 94%yield at 0.5 mg/kg.Analytical results suggested that transfer of tested substances to the larval biomass was substance-and concentration-specific,but appeared to be correlated to reduced yields and the presence of PBO.Transfer of organophosphates was overall low(<2%),but ranged from 8%to 75%for pyrethroids.Due to very low limits in insect biomass(~0.01 mg/kg),high transfer may result in noncompliance.It is recommended that rearing companies implement lower contractual thresholds,and that policymakers consider adjusting legally allowed maximum residue levels in insect feed.展开更多
Plants exploit phenotypic plasticity to adapt their growth and development to prevailing environmental conditions.Interpretation of light and temperature signals is aided by the circadian system,which provides a tempo...Plants exploit phenotypic plasticity to adapt their growth and development to prevailing environmental conditions.Interpretation of light and temperature signals is aided by the circadian system,which provides a temporal context.Phenotypic plasticity provides a selective and competitive advantage in nature but is obstructive during large-scale,intensive agricultural practices since economically important traits(including vegetative growth and flowering time)can vary widely depending on local environmental condi-tions.This prevents accurate prediction of harvesting times and produces a variable crop.In this study,we sought to restrict phenotypic plasticity and circadian regulation by manipulating signaling systems that govern plants'responses to environmental signals.Mathematical modeling of plant growth and develop-ment predicted reduced plant responses to changing environments when circadian and light signaling pathways were manipulated.We tested this prediction by utilizing a constitutively active allele of the plant photoreceptor phytochrome B,along with disruption of the circadian systemvia mutation of EARLYFLOW-ERING3.We found that these manipulations produced plants that are less responsive to light and temper-ature cues and thus fail to anticipate dawn.These engineered plants have uniform vegetative growth and flowering time,demonstrating how phenotypic plasticity can be limited while maintaining plant productiv-ity.This has significant implications for future agriculture in both open fields and controlled environments.展开更多
The diversity of filamentous fungi that can grow at high ambient pH values(i.e.,8–11)remains largely understudied.Here we study 100 alkalitolerant and alkaliphilic isolates from the soils around the basin of soda lak...The diversity of filamentous fungi that can grow at high ambient pH values(i.e.,8–11)remains largely understudied.Here we study 100 alkalitolerant and alkaliphilic isolates from the soils around the basin of soda lakes in Asia and Africa to assess the major evolutionary lineages and morphologies pertinent to the alkaliphilic trait in filamentous fungi.The Emericellopsis lineage(Hypocreales,Hypocreomycetidae),along with Plectosphaerellaceae(Hypocreomycetidae),Pleosporaceae(Dothideomycetes),Chaetomiaceae(Sordariomycetidae)families appeared to be overrepresented with strong alkalitolerants and effective alkaliphiles.In particular,Sodiomyces species(Plectosphaerellaceae),Acrostalagmus luteoalbus(Plectosphaerellaceae),Emericellopsis alkalina(Hypocreales),Thielavia sp.(Chaetomiaceae),and Alternaria sect.Soda(Pleosporaceae)grew best at high ambient pH.The pH tolerance of Chordomyces antarcticum,Acrostalagmus luteoalbus and some other species was largely affected by the presence of extra Na+in the growth medium.Moderate alkalitolerants included Scopulariopsis members(Microascales),Fusarium,Cladosporium,and many asexual acremonium-like species from Bionectriaceae.Weak alkalitolerants were represented by sporadic isolates of Penicillium,Purpureocillium lilacinum,and Alternaria alternata species,with the growth optimum at neutral or acidic pH.Weak alkalitolerants develop loose dry chains of spores easily dispersed by air.Their presence at low frequency with the growth optimum at neutral or acidic pH leads us to treat them as transient species in the alkaline soils,as those are also ubiquitous saprobes in normal soils.Our phylogenetic analyses show that the alkaliphilic trait in filamentous fungi has evolved several times.Several lineages harboring strong alkalitolerants derived from the known marine-borne fungi(Emericellopsis,Alternaria sect.Phragmosporae),or fall within the fungi associated with halophytic grasses(Pleosporaceae).Soda soils contain a diversity of fungi that range from weak alkalitolerant to alkaliphilic,which in few cases is associated with darkly pigmented mycelium and formation of microsclerotia.The alkaliphilic trait is spread throughout the Ascomycota,and usually juxtaposes with slime-covered polyphyletic acremonium-,verticillium-,gliocladium-types of asexual morphology,hyphae aggregating in chords,and enclosed fruit bodies.展开更多
Arabidopsis UV RESISTANCE LOCUS8 （UVR8） is a UV-B-specific signaling component that regulates expression of a range of genes concerned with UV protection. Here, we investigate the interaction of UVR8 with chromatin....Arabidopsis UV RESISTANCE LOCUS8 （UVR8） is a UV-B-specific signaling component that regulates expression of a range of genes concerned with UV protection. Here, we investigate the interaction of UVR8 with chromatin. Using antibodies specific to UVR8 in chromatin immunoprecipitation （ChiP） assays with wild-type plants, we show that native UVR8 binds to chromatin in vivo. Similar experiments using an anti-GFP antibody with plants expressing a GFP-UVR8 fusion show that UVR8 associates with a relatively small region of chromatin containing the HY5 gene. UVR8 interacts with chromatin containing the promoter regions of other genes, but not with all the genes it regulates. UV-B is not required for the interaction of UVR8 with chromatin because association with several gene loci is observed in the absence of UV-B. Pulldown assays demonstrate that UVR8 associates with histones in vivo and competition experiments indicate that the interaction is preferentially with histone H2B. ChIP experiments using antibodies that recognize specific histone modifications indicate that the UV-B-stimulated transcription of some genes may be correlated with histone modification. In particular, the ELIP1 promoter showed a significant enrichment of diacetyl histone H3 （K9/K14） following UV-B exposure. These findings increase understanding of the interaction of the key UV-B-specific regulator UVR8 with chromatin.展开更多
Phototropins （phot1 and phot2） are blue-light receptor kinases controlling a range of responses that optimize the photosynthetic efficiency of plants. Light sensing is mediated by two flavin-binding motifs, known as...Phototropins （phot1 and phot2） are blue-light receptor kinases controlling a range of responses that optimize the photosynthetic efficiency of plants. Light sensing is mediated by two flavin-binding motifs, known as LOVl and LOV2, located within the N-terminal region of the protein. Photoexcitation via LOV2 leads to activation of the C-terminal kinase domain and consequently receptor autophosphorylation. However, knowledge of the in-vivo phosphorylation sites for Arabidopsis phototropins is lacking and has impeded progress in elucidating the functional significance of receptor phos- phorylation. We have purified photl from Arabidopsis and identified the in-vivo sites of receptor phosphorylation by liquid chromatography tandem mass spectrometry. Arabidopsis-derived photl binds flavin mononucleotide as chromophore and is phosphorylated at four major sites located upstream of LOV2 （Ser^58, Ser^85, Ser^350, and Ser^410）, three of which are induced by blue light. Nevertheless, structure-function analysis indicates that the biological activity of photl can be attributed to a modular unit comprising the LOV2-kinase region of the protein. Thus, peptide regions upstream of LOV2, including the sites of receptor phosphorylation identified here, do not appear to be important for receptor signaling. By contrast, these regions may be necessary for maximizing stomatal performance and possibly light-induced relocalization of photl.展开更多
Parasitoids have long proven to be model organisms in studying resourcerelated constraints on immature development. Here we examine the relationship between host cocoon （= pupal） size in the gregarious endoparasitoi...Parasitoids have long proven to be model organisms in studying resourcerelated constraints on immature development. Here we examine the relationship between host cocoon （= pupal） size in the gregarious endoparasitoid wasp, Cotesia glomerata, and development time and adult size in the solitary idiobiont hyperparasitoid, Pteromalus semotus. Little is known about the biology or ecology of this ecto-hyperparasitoid species, although it is one of the major secondary hyperparasitoids of C. glomerata. The size of the adult wasp covaried with the size of the host cocoon at parasitism. Moreover, female wasps were larger than male wasps for a given cocoon size. Adult wasps have remarkably long life-spans, 3 months on average. Longevity did not significantly differ with sex. We also examined how larvae of P. semotus exclude other potential competitors. P. semotus is protandrous, with females taking significantly longer to complete their development than males. In experiments where several eggs of P. semotus were placed on individual pupae of C. glomerata, newly hatched hyperparasitoid larvae moved rapidly over the surface of the host and destroyed the eggs of any conspecifics by biting them before they would initiate feeding on host tissues. Our results are discussed in relation to those with other studies with solitary ichneumonid idiobiont hyperparasitoids of C. glomerata.展开更多
Plants have developed multiple strategies to respond to salt stress.In order to identify new traits related to salt tolerance,with potential breeding application,the research focus has recently been shifted to include...Plants have developed multiple strategies to respond to salt stress.In order to identify new traits related to salt tolerance,with potential breeding application,the research focus has recently been shifted to include root system architecture(RSA)and root plasticity.Using a simple but effective root phenotyping system containing soil(rhizotrons),RSA of several tomato cultivars and their response to salinity was investigated.We observed a high level of root plasticity of tomato seedlings under salt stress.The general root architecture was substantially modified in response to salt,especially with respect to position of the lateral roots in the soil.At the soil surface,where salt accumulates,lateral root emergence was most strongly inhibited.Within the set of tomato cultivars,H1015 was the most tolerant to salinity in both developmental stages studied.A significant correlation between several root traits and aboveground growth parameters was observed,highlighting a possible role for regulation of both ion content and root architecture in salt stress resilience.展开更多
文摘Potassium （K^＋） is an essential macronutrient for all living organisms and large amounts are required for plant growth and development. In many regions of Asia K＋-fertilization has been neglected and soils have become K＋-depleted. K＋- deficiency in the field diminishes not only crop production but also leads to environmental problems due to inefficient usage and leaching of nitrate. Consequences of K^＋-deficiency on crop production range from decreased biomass, nutritional quality and taste of the crops to inferior harvest and storage properties, as well as increased susceptibility to disease. Effects of K^＋-deficiency on plant physiology include decreased photosynthetic rate, impaired tissue allocation of sugars and amino acids, decreased protein synthesis.
文摘Plant-parasitic nematodes caused severe yield loss in major crops all over the world.The most wild-used strategies to combat the nematodes is the chamical nematicides,but the overuse of synthetic nematicides threaten sustainable agriculture development.Other strategies,like resistance cultivars and crop rotation,have limited efficiency.Thus,the utilization of molecular biotechnology like RNA interference(RNAi)would be one of the alternative ways to enhance plant resistance against nematodes.RNAi has already used as a tool for gene functional analysis in a wide range of species,especially in the non-parasitic nematode,Caenorhabtidis elegans.In plant-parasitic nematodes,RNAi is induced by soaking nematodes with double strand RNA(dsRNA)solution mixed with neurostimulants,which is called in vitro RNAi delivery method.In another way around,in planta RNAi method,which is Host-mediated RNAi approach also showed a great success in conferring the resistance against root-knock nematodes.Two main advantages of RNAi-based transgenics are RNAi technology do not produce any functional foreign proteins and it target organisms in a sequence-specific way.Even though the development of RNAi-based transgenics against plant-parasitic nematodes is still in the initial phase,it offers the prospect into a novel nematode control strategy in the future.
文摘The dry-extract system for (near) infrared (DESIR) technique was implemented using reflectance near-infrared spec-troscopy in context of detection of contact pesticide residues on fruit. Based on chemical structure, spectra features and regression statistics for PLSR models, a product containing metiram and pyraclostrobin was chosen from six pesticides for further consideration. Regression models based on spectra of dry extracts of aqueous solutions and either acetone or water washes of contaminated fruit were encouraging (RMSECV of approximately 0.03 - 0.06 mg a.i.). This level of analytical performance would support the use of the technique as a rapid screening tool, with suspect samples then subject to the reference GC-MS analysis method. However, the PLSR model performance was poor across populations of fruit, suggesting that matrix changes in the solvent wash between sets of fruit is problematic. Further work is required to establish whether sufficient variation can be built into a calibration set to overcome this issue, without degrading model performance to the point where it loses practical application.
文摘Ganoderma lucidum is a wildly used medicinal mushroom and has been used in East Asia because of its health-benefit effects. G. lucidum contains various compounds with different biological activities, which include anti-tumour, anti-viral, and anti-malaria effect. Ganoderic acid (GA) is a triterpenoid from G. lucidum. The biosynthesis of GA in G. lucidum is induced by stressors including various elicitors or signaling molecules, and artificially placing elicitors would enhance GA production. In this paper, bioactivities and potential applications of GAs would be focused, and the elicitation strategies for GA production are also highlighted based on the fundamental role of ROS, JA, Ca2+ and NO, which would shed light to developing a novel approach to manipulating the biosynthesis of GA in the future.
基金financially supported by OCI Nitrogen,Geleen,The Netherlands
文摘Our attitude towards mineral nitrogen (N) fertilizers is ambivalent. N fertilizers have on one hand increased our supply of food, feed and other bio-based raw materials tremendously and also improved the use efficiency of land and labor, but have on the other hand a negative impact on the quality of the environment and contributed to the depletion of fossil fuel reserves. This awareness has resulted in strong pleas to spend much more attention to the recycling of N containing downstream “wastes”. It is, however, naive to assume that even perfect recycling suffices to offer the same number of people the same diet without inputs of “new” N, as inevitable losses of N make compensations indispensable. “New” N can be derived from either biological N fixation (“legumes”) or from industrially fixed N (“fertilizer”). The existing literature provides no evidence that the use of N fertilizers is per se unsustainable, as these fertilizers can also be made from renewable forms of energy. Besides, soil health and human health appear sensitive for the dosage but not for the form of N. It is yet imperative to reduce the input of “new” N as much as possible, so as to minimize adverse environmental effects. Measures to this end are a more precise assessment of crop N requirements, a better timing and positioning of N inputs, and any measure supporting the acceptance of “wastes” by farmers. The present paper elaborates the above aspects.
基金financial support of the China Scholarship Council(201913043)Hainan University,Agricultural Science and Research Excellence Talents of Ministry of Agriculture and Rural Affairs,China(202105510311095).
文摘Adequate dietary zinc intake remains a public health challenge in China.Also,there is a lack of information on the relationship between Zn intake and food consumption patterns across provinces and over time.In this study,data from the China Health and Nutrition Survey 2004-2011(21,266 individuals)was used to explore associations between dietary Zn intake and sociodemographic factors.Zn intake per person declined from 11.1 mg·d^(-1)in 2004 to 9.89 mg·d^(-1)in 2011,with reduction in cereal consumption the greatest contributor to this.However,the reduction resulting from the lower cereal consumption was only partly compensated by an increase in consumption of Zn-rich foods.The percentage of the study population with inadequate Zn intake increased from 23% in 2004 to 37% in 2011.While Zn intake was positively associated with income levels in each survey year,the time trend for all income levels was a gradually reducing Zn intake.In all years,males had an average higher dietary Zn intake,whereas no significant difference was found between living areas.In conclusion,this study shows that dietary Zn inadequacy was high and has increased over the studied period.Remediation could be sought by shifting dietary patterns toward more Zn-dense food or by enhancing Zn concentration through biofortification.
文摘Thellungiella salsuginea （halophila） is a close relative of Arabidopsis thaliana but, unlike A. thaliana, it grows well in extreme conditions of cold, salt, and drought as well as nitrogen limitation. Over the last decade, many laboratories have started to use Thellungiella to investigate the physiological, metabolic, and molecular mechanisms of abiotic stress tolerance in plants, and new knowledge has been gained in particular with respect to ion transport and gene expression. The advantage of Thellungiella over other extremophile model plants is that it can be directly compared with Arabidopsis, and therefore generate information on both essential and critical components of stress tolerance. Thellungiella research is supported by a growing body of technical resources comprising physiological and molecular protocols, ecotype collections, expressed sequence tags, cDNA-libraries, microarrays, and a pending genome sequence. This review summarizes the current state of knowledge on Thellungiella and re-evaluates its usefulness as a model for research into plant stress tolerance.
基金Supported by the National Science Foundation, USA, grants MCB 0091384 and 0444504 to WRB, MCB0444390 to RAB, and by the UK Biotechnology and Biological Sciences Research Council, grant BB/C000366/1 to JMC. Publication of this paper is supported by the National Natural Science Foundation of China （30624808） and Science Publication Foundation of the Chinese Academy of Sciences.
文摘The phototropins phot1 and phot2 are plant blue-light receptors that mediate phototropism, chloroplast movements, stomatal opening, leaf expansion, the rapid Inhibition of hypocotyl growth in etiolated seedlings, and possibly solar tracking by leaves in those species in which It occurs. The phototroplns are plasma membrane-associated hydrophilic proteins with two chromophore domains （designated LOV1 and LOV2 for their resemblance to domains In other signaling proteins that detect light, oxygen, or voltage） in their Nterminal half and a classic serine/threonlne kinase domain in their C-terminal half. Both chromophore domains bind flavin mononucleotide （FMN） and both undergo light-activated formation of a covalent bond between a nearby cystelne and the C（4a） carbon of the FMN to form the signaling state. LOV2-cystelnyl adduct formation leads to the release downstream of a tightly bound amphlpathlc α-helix, a step required for activation of the klnase function. This cysteinyl adduct then slowly decays over a matter of seconds or minutes to return the photoreceptor chromophore modules to their ground state. Functional LOV2 is required for light-activated phosphorylation and for various blue-light responses mediated by the phototroplns. The function of LOV1 is still unknown, although It may serve to modulate the signal generated by LOV2. The LOV domain Is an ancient chromophore module found In a wide range of otherwise unrelated proteins In fungi and prokaryotes, the latter Including cyanobacterla, eubacterla, and archaea. Further general reviews on the phototropins are those by Celaya and Liscum （2005） and Christie and Briggs （2005）.
基金supported by Bualuang Chair Professor Fund(contract number TUBC 08/2022)Thailand Science Research and Innovation Fundamental Fund fiscal year 2023(Project no.4182267).
文摘Mycotoxins are the most frequently occurring natural contaminant in food and feed.Their occurrence in crops and animal feed represents an enormous challenge,particularly for livestock farmers in terms of increased production costs,reduced animal performance and profitability.This study investigates the scale of emerging mycotoxins contamination of crops and animal feeds globally,and evaluates their impacts on the health and performance of livestock,especially when they co-occur alongside regulated mycotoxins.Emerging mycotoxins including nivalenol,enniatins,beauvericin,diacetoxyscirpenol,fusaric acid,patulin,moniliformin and sterigmatocystin were found to be the most prevalent contaminants of cereals and other feed commodities worldwide.The pooled mean levels for beauvericin,nivalenol,enniatins,moniliformin,sterigmatocystin,diacetoxyscirpenol,fusaric acid,and patulin were 386,421,7,854,204,136,126,370 and 138 mg/kg,respectively.In terms of toxicity,co-occurrence of emerging mycotoxins with each other and also with regulated mycotoxins profoundly impacts livestock performance,even at low levels.Therefore,there is a need for cumulative risk assessments to evaluate the health risks associated with simultaneous exposure to emerging and regulated mycotoxins and also to develop effective mitigation strategies.
基金funded by the Netherlands Ministry of Economic Affairs(further:The Ministry)through a Public-Private Partnership project("Controlling the safety of insects for food and feed")of the Topsector AgriFood(LWV19099).
文摘Black soldier fly larvae(Hermetia illucens)receive growing interest as a potential alternative animal feed source.These insects may be exposed to insecticide residues in the rearing substrate.This study aimed to investigate the effects of six different pyrethroid and organophosphate insecticides on this insect species'performance.The toxicity of two"model"substances for each of these classes(cypermethrin;pirimiphosmethyl)was quantified,with and without the synergist piperonyl butoxide(PBO).Critical effect doses corresponding to 10%yield(CED10)for cypermethrin(0.4 mg/kg)and pirimiphos-methyl(4.8 mg/kg)were determined.The addition of PBO to cypermethrin enhanced its relative potency with a factor 2.6.These data were compared against the relative toxicity of two analogue substances in each class(permethrin,deltamethrin;chlorpyrifosmethyl,malathion).Results suggest that exposure to concentrations complying with legal limits can cause significant reductions in yield.Exposure to multiple substances at lower concentrations resulted in negative additive and synergistic effects.Of the tested substances,deltamethrin was most toxic,causing 94%yield at 0.5 mg/kg.Analytical results suggested that transfer of tested substances to the larval biomass was substance-and concentration-specific,but appeared to be correlated to reduced yields and the presence of PBO.Transfer of organophosphates was overall low(<2%),but ranged from 8%to 75%for pyrethroids.Due to very low limits in insect biomass(~0.01 mg/kg),high transfer may result in noncompliance.It is recommended that rearing companies implement lower contractual thresholds,and that policymakers consider adjusting legally allowed maximum residue levels in insect feed.
基金supported by the UKRI(BB/S005404/1 and BB/Z514469/1)the Gatsby Charitable Foundation,the Perry Foundation(to S.F.E.)+1 种基金the Douglas Bomford Trust(to S.F.E.)a William H.Danforth Plant Sciences Fellowship(to K.N.E.).
文摘Plants exploit phenotypic plasticity to adapt their growth and development to prevailing environmental conditions.Interpretation of light and temperature signals is aided by the circadian system,which provides a temporal context.Phenotypic plasticity provides a selective and competitive advantage in nature but is obstructive during large-scale,intensive agricultural practices since economically important traits(including vegetative growth and flowering time)can vary widely depending on local environmental condi-tions.This prevents accurate prediction of harvesting times and produces a variable crop.In this study,we sought to restrict phenotypic plasticity and circadian regulation by manipulating signaling systems that govern plants'responses to environmental signals.Mathematical modeling of plant growth and develop-ment predicted reduced plant responses to changing environments when circadian and light signaling pathways were manipulated.We tested this prediction by utilizing a constitutively active allele of the plant photoreceptor phytochrome B,along with disruption of the circadian systemvia mutation of EARLYFLOW-ERING3.We found that these manipulations produced plants that are less responsive to light and temper-ature cues and thus fail to anticipate dawn.These engineered plants have uniform vegetative growth and flowering time,demonstrating how phenotypic plasticity can be limited while maintaining plant productiv-ity.This has significant implications for future agriculture in both open fields and controlled environments.
基金supported by the Laboratory of Genetics at Wageningen University(The Netherlands),RSCF grant №14-50-00029,RFBR grants №15-04-06975,№15-04-06260(Russia).
文摘The diversity of filamentous fungi that can grow at high ambient pH values(i.e.,8–11)remains largely understudied.Here we study 100 alkalitolerant and alkaliphilic isolates from the soils around the basin of soda lakes in Asia and Africa to assess the major evolutionary lineages and morphologies pertinent to the alkaliphilic trait in filamentous fungi.The Emericellopsis lineage(Hypocreales,Hypocreomycetidae),along with Plectosphaerellaceae(Hypocreomycetidae),Pleosporaceae(Dothideomycetes),Chaetomiaceae(Sordariomycetidae)families appeared to be overrepresented with strong alkalitolerants and effective alkaliphiles.In particular,Sodiomyces species(Plectosphaerellaceae),Acrostalagmus luteoalbus(Plectosphaerellaceae),Emericellopsis alkalina(Hypocreales),Thielavia sp.(Chaetomiaceae),and Alternaria sect.Soda(Pleosporaceae)grew best at high ambient pH.The pH tolerance of Chordomyces antarcticum,Acrostalagmus luteoalbus and some other species was largely affected by the presence of extra Na+in the growth medium.Moderate alkalitolerants included Scopulariopsis members(Microascales),Fusarium,Cladosporium,and many asexual acremonium-like species from Bionectriaceae.Weak alkalitolerants were represented by sporadic isolates of Penicillium,Purpureocillium lilacinum,and Alternaria alternata species,with the growth optimum at neutral or acidic pH.Weak alkalitolerants develop loose dry chains of spores easily dispersed by air.Their presence at low frequency with the growth optimum at neutral or acidic pH leads us to treat them as transient species in the alkaline soils,as those are also ubiquitous saprobes in normal soils.Our phylogenetic analyses show that the alkaliphilic trait in filamentous fungi has evolved several times.Several lineages harboring strong alkalitolerants derived from the known marine-borne fungi(Emericellopsis,Alternaria sect.Phragmosporae),or fall within the fungi associated with halophytic grasses(Pleosporaceae).Soda soils contain a diversity of fungi that range from weak alkalitolerant to alkaliphilic,which in few cases is associated with darkly pigmented mycelium and formation of microsclerotia.The alkaliphilic trait is spread throughout the Ascomycota,and usually juxtaposes with slime-covered polyphyletic acremonium-,verticillium-,gliocladium-types of asexual morphology,hyphae aggregating in chords,and enclosed fruit bodies.
文摘Arabidopsis UV RESISTANCE LOCUS8 （UVR8） is a UV-B-specific signaling component that regulates expression of a range of genes concerned with UV protection. Here, we investigate the interaction of UVR8 with chromatin. Using antibodies specific to UVR8 in chromatin immunoprecipitation （ChiP） assays with wild-type plants, we show that native UVR8 binds to chromatin in vivo. Similar experiments using an anti-GFP antibody with plants expressing a GFP-UVR8 fusion show that UVR8 associates with a relatively small region of chromatin containing the HY5 gene. UVR8 interacts with chromatin containing the promoter regions of other genes, but not with all the genes it regulates. UV-B is not required for the interaction of UVR8 with chromatin because association with several gene loci is observed in the absence of UV-B. Pulldown assays demonstrate that UVR8 associates with histones in vivo and competition experiments indicate that the interaction is preferentially with histone H2B. ChIP experiments using antibodies that recognize specific histone modifications indicate that the UV-B-stimulated transcription of some genes may be correlated with histone modification. In particular, the ELIP1 promoter showed a significant enrichment of diacetyl histone H3 （K9/K14） following UV-B exposure. These findings increase understanding of the interaction of the key UV-B-specific regulator UVR8 with chromatin.
文摘Phototropins （phot1 and phot2） are blue-light receptor kinases controlling a range of responses that optimize the photosynthetic efficiency of plants. Light sensing is mediated by two flavin-binding motifs, known as LOVl and LOV2, located within the N-terminal region of the protein. Photoexcitation via LOV2 leads to activation of the C-terminal kinase domain and consequently receptor autophosphorylation. However, knowledge of the in-vivo phosphorylation sites for Arabidopsis phototropins is lacking and has impeded progress in elucidating the functional significance of receptor phos- phorylation. We have purified photl from Arabidopsis and identified the in-vivo sites of receptor phosphorylation by liquid chromatography tandem mass spectrometry. Arabidopsis-derived photl binds flavin mononucleotide as chromophore and is phosphorylated at four major sites located upstream of LOV2 （Ser^58, Ser^85, Ser^350, and Ser^410）, three of which are induced by blue light. Nevertheless, structure-function analysis indicates that the biological activity of photl can be attributed to a modular unit comprising the LOV2-kinase region of the protein. Thus, peptide regions upstream of LOV2, including the sites of receptor phosphorylation identified here, do not appear to be important for receptor signaling. By contrast, these regions may be necessary for maximizing stomatal performance and possibly light-induced relocalization of photl.
文摘Parasitoids have long proven to be model organisms in studying resourcerelated constraints on immature development. Here we examine the relationship between host cocoon （= pupal） size in the gregarious endoparasitoid wasp, Cotesia glomerata, and development time and adult size in the solitary idiobiont hyperparasitoid, Pteromalus semotus. Little is known about the biology or ecology of this ecto-hyperparasitoid species, although it is one of the major secondary hyperparasitoids of C. glomerata. The size of the adult wasp covaried with the size of the host cocoon at parasitism. Moreover, female wasps were larger than male wasps for a given cocoon size. Adult wasps have remarkably long life-spans, 3 months on average. Longevity did not significantly differ with sex. We also examined how larvae of P. semotus exclude other potential competitors. P. semotus is protandrous, with females taking significantly longer to complete their development than males. In experiments where several eggs of P. semotus were placed on individual pupae of C. glomerata, newly hatched hyperparasitoid larvae moved rapidly over the surface of the host and destroyed the eggs of any conspecifics by biting them before they would initiate feeding on host tissues. Our results are discussed in relation to those with other studies with solitary ichneumonid idiobiont hyperparasitoids of C. glomerata.
基金the Alfonso Martin Escudero Foundation and the NWO SusCrop-ERA-NET ROOT pro-ject ALW.FACCE.24The project ROOT was carried out under the ERA-NET Cofund SusCrop(Grant No.771134)the Joint Programming Initiative on Agricul-ture,Food Security and Climate Change(FACCE-JPI).
文摘Plants have developed multiple strategies to respond to salt stress.In order to identify new traits related to salt tolerance,with potential breeding application,the research focus has recently been shifted to include root system architecture(RSA)and root plasticity.Using a simple but effective root phenotyping system containing soil(rhizotrons),RSA of several tomato cultivars and their response to salinity was investigated.We observed a high level of root plasticity of tomato seedlings under salt stress.The general root architecture was substantially modified in response to salt,especially with respect to position of the lateral roots in the soil.At the soil surface,where salt accumulates,lateral root emergence was most strongly inhibited.Within the set of tomato cultivars,H1015 was the most tolerant to salinity in both developmental stages studied.A significant correlation between several root traits and aboveground growth parameters was observed,highlighting a possible role for regulation of both ion content and root architecture in salt stress resilience.
