Given the increased circulation time after fishing,a series of changes take place in live clams,leading to a deterioration in quality even after death.Thus,in this study,we aimed to explore the optimal mode of transpo...Given the increased circulation time after fishing,a series of changes take place in live clams,leading to a deterioration in quality even after death.Thus,in this study,we aimed to explore the optimal mode of transportation of clams.The container for holding clams was reformed,and a water circulation temperature control system was established.The physiological responses of clams during anhydrous and watery transportation at two temperatures(4 and 15℃)were investigated based on the aforementioned system.When comparing the transportation patterns after 3 d of transport,a higher survival rate was observed at 4℃(97%)than at 15℃(63%)in the anhydrous transportation groups and a lower survival rate was observed at 4℃(93%)than at 15℃(99%)in the watery transportation groups.In addition,the glycogen content,condition index(CI),and adenylate energy charge(A.E.C)value were higher at4℃((40.87±0.99)mg g^(-1),13.71%±0.50%and 57.45%±1.60%)than at 15℃((30.54±0.81)mg g^(-1),9.09%±0.30%and 43.12%±1.65%)in the anhydrous transportation groups.In the watery transportation groups,a lower glycogen content,CI,and A.E.C.value were observed at 4℃((33.78±0.84)mg g^(-1),9.78%±0.50%and 64.65%±1.25%)than at 15℃((41.53±0.93)mg g^(-1),12.72%±0.83%and 71.58%±1.27%).Results from this study show that anhydrous transportation(4℃)is the optimal transport condition for clams to maintain a high quality and good physiological conditions.Thus,this study will be particularly useful for establishing shellfish transportation systems.展开更多
Crop yield loss due to soil salinization is an increasing threat to agriculture worldwide.Salt stress drastically affects the growth,development,and grain productivity of rice(Oryza sativa L.),and the improvement of r...Crop yield loss due to soil salinization is an increasing threat to agriculture worldwide.Salt stress drastically affects the growth,development,and grain productivity of rice(Oryza sativa L.),and the improvement of rice tolerance to salt stress is a desirable approach for meeting increasing food demand.The main contributors to salt toxicity at a global scale are Na^(+)and Cl^(-)ions,which affect up to 50%of irrigated soils.Plant responses to salt stress occur at the organismic,cellular,and molecular levels and are pleiotropic,involving(1)maintenance of ionic homeostasis,(2)osmotic adjustment,(3)ROS scavenging,and(4)nutritional balance.In this review,we discuss recent research progress on these four aspects of plant physiological response,with particular attention to hormonal and gene expression regulation and salt tolerance signaling pathways in rice.The information summarized here will be useful for accelerating the breeding of salt-tolerant rice.展开更多
Drought is one of the most significant natural disasters in the arid and semi-arid areas of China.Populations or plant organs often differ in their responses to drought and other adversities at different growth stages...Drought is one of the most significant natural disasters in the arid and semi-arid areas of China.Populations or plant organs often differ in their responses to drought and other adversities at different growth stages.At present,little is known about the size-and leaf age-dependent differences in the mechanisms of shrub-related drought resistance in the deserts of China.Here,we evaluated the photosynthetic and physiological responses of Artemisia ordosica Krasch.to drought stress using a field experiment in Mu Us Sandy Land,Ningxia Hui Autonomous Region,China in 2018.Rainfall was manipulated by installing outdoor shelters,with four rainfall treatments applied to 12 plots(5 m×5 m).There were four rainfall levels,including a control and rainfall reductions of 30%,50%and 70%,each with three replications.Taking individual crown size as the dividing basis,we measured the responses of A.ordosica photosynthetic and physiological responses to drought at different growth stages,i.e.,large-sized(>0.5 m^(2))and small-sized(≤0.5 m^(2))plants.The leaves of A.ordosica were divided into old leaves and young leaves for separate measurement.Results showed that:(1)under drought stress,the transfer efficiency of light energy captured by antenna pigments to the photosystem II(PSII)reaction center decreased,and the heat dissipation capacity increased simultaneously.To resist the photosynthetic system damage caused by drought,A.ordosica enhanced its free radical scavenging capacity by activating its antioxidant enzyme system;and(2)growth stage and leaf age had effects on the reaction of the photosynthetic system to drought.Small A.ordosica plants could not withstand severe drought stress(70%rainfall reduction),whereas large A.ordosica individuals could absorb deep soil water to ensure their survival in severe drought stressed condition.Under 30%and 50%rainfall reduction conditions,young leaves had a greater ability to resist drought than old leaves,whereas the latter were more resistant to severe drought stress.The response of A.ordosica photosynthetic system reflected the trade-off at different growth stages and leaf ages of photosynthetic production under different degrees of drought.This study provides a more comprehensive and systematic perspective for understanding the drought resistance mechanisms of desert plants.展开更多
Foxtail millet(Setaria italica L.),a member of the Paniceae family,is a temperate and tropical grass species that is widely cultivated on the Eurasian continent.It is Chinese in origin and possesses a small genome,sho...Foxtail millet(Setaria italica L.),a member of the Paniceae family,is a temperate and tropical grass species that is widely cultivated on the Eurasian continent.It is Chinese in origin and possesses a small genome,short growth cycle,and strong natural abiotic stress resistance.Elucidating the mechanism of millet tolerance to salt stress is becoming increasingly important with increasing soil salinization limiting crop productivity.The responses and mechanisms of tolerance to salt stress from other model plants such as Arabidopsis and rice,were compared with those from foxtail millet to summarize current research on responses to salt stress.Numerous processes are involved in these processes,including physiological reactions,sensing,signaling,and control at the transcriptional,post-transcriptional,and epigenetic levels.To increase crop productivity and agricultural sustainability,a variety of technologies can be used to investigate how salt tolerance is mediated by physiological and molecular processes in foxtail millet.展开更多
Different plants have physiological responses under Al stress,but there is no systematic study to examine physiological responses of herbaceous plants under Al stress.The aim of this study is to investigate the effect...Different plants have physiological responses under Al stress,but there is no systematic study to examine physiological responses of herbaceous plants under Al stress.The aim of this study is to investigate the effect of Al on physiological characteristics of four herbaceous plants,which distributed in red soil area in South China,and to analyze the differences in physiological responses to Al stress between the four herbaceous plants.Four herbaceous plants(Pharbitis nil,Cassia occidentlis,Echinochloa colonum and Aeschynomene indica)were used,and the seed germi-nation percentage,the contents of chlorophyll,proline,and malondialdehyde(MDA),membrane permeability(MP),soluble sugar,and activities of peroxides(POD)and cata-lase(CAT)in leaves under five Al^(3+)treatments(0,80,400,2000,and 10000 mg/L)were assayed with the sand culture method.The results showed remarkable effects of Al^(3+)on physiological characteristics of these four herbaceous plants.The seeds of all the four species could not germinate at 10000 mg/L,and the growth of all plants were retarded under the 2000 mg/L Al^(3+)treatment.Compared with the control,2000 mg/L Al^(3+)significantly(P<0.05)reduced the con-tents of chlorophyll a and chlorophyll a+b,and increased the contents of MDA and MP.The content of proline in-creased very significantly(P<0.01)and activities of POD and CAT were depressed.The contents of MDA and MP in leaves of P.nil and A.indica decreased,and the activities of POD and CAT in leaves of the two plants increased under 80 mg/L and 400 mg/L.However,the changes in C.occidentlis leaves were opposite to those of the above two plants.The changes in leaves of E.colonum were similar to those of P.nil and A.indica at 80 mg/L,but were opposite to those at 400 mg/L Al^(3+).It is suggested that plants with higher ac-tivities of POD and CAT,more contents of chlorophyll and proline,and lower contents of MDA and MP consequently improve the tolerance to Al stress under low and middle Al treatments.展开更多
Green foxtail(Setaria viridis)is a notorious weed in corn fields in Heilongjiang Province.To investigate the best method to break the seed dormancy of green foxtail and its physiological response to topramezone,this s...Green foxtail(Setaria viridis)is a notorious weed in corn fields in Heilongjiang Province.To investigate the best method to break the seed dormancy of green foxtail and its physiological response to topramezone,this study selected newly harvested and one-year stored green foxtail seeds as research subjects.The seeds were treated with HCl,Na OH,gibberellic acid(GA),different water temperatures and polyethylene glycol(PEG)to study the seed dormancy and drought resistance of green foxtail.The results showed that newly harvested seeds exhibited dormancy,and treatments with HCl,NaOH and different water temperatures were unable to break the dormancy.Soaking the seeds in GA could overcome dormancy,but the seeds failed to germinate when exposed to 25%PEG concentration.When topramezone was applied at rates of 22.5 and 45.0 g a.i.·hm^(-2)at the 3-leaf and 5-leaf stages,respectively,the chlorophyll content reached the lowest value at 28 days after treatment(DAT).At the 7-leaf stage,the chlorophyll content reached the lowest value at 7 DAT.The activity of 4-hydroxyphenylpy-ruvate dioxygenase(HPPD)enzyme after topramezone application reached the maximum value at 7 DAT for different leaf ages,and the higher the leaf age,the higher the HPPD activity,which was an important factor contributing to the resistance of green foxtail to topramezone.展开更多
Background: The present study was designed to evaluate load carriage performance at extremely high altitudes with different loads and walking speeds in terms of physiological evaluation. The degree of maximum oxygen c...Background: The present study was designed to evaluate load carriage performance at extremely high altitudes with different loads and walking speeds in terms of physiological evaluation. The degree of maximum oxygen consumption changes at high altitudes was also examined.Methods: Twelve Indian Army soldiers were acclimatized at altitudes of 3,505 m and 4,300 m. They walked for 10 minutes on a motorized treadmill at 2.5km/h and 3.5km/h speeds during carrying no loads and three magnitudes of load(10.7kg, 21.4kg, 30kg) at both altitudes. Physiological parameters such as oxygen consumption, energy expenditure, heart rate, and ventilation were recorded for each breath using a gas analyzer. The rating of perceived exertion was also noted after each load carriage session. Maximal oxygen consumption(VO2max) was measured at sea level and the two high altitudes, and respective relative workloads(% of VO2max) were calculated from oxygen consumption. Repeated measure ANOVA was applied to reveal the significant effects of the independent variables.Results: The participants had significant reductions in VO2 max with rising altitude. Marked increases in almost all physiological parameters were observed with increasing load, altitude, and speed. The soldiers expressed heavy perceived exertion levels with higher loads at 3.5km/h at the two high altitudes.Conclusions: Considering the physiological responses, expressions of perceived exertion and changes in relative work load at both of the high altitudes. Indian soldiers are advised to walk slowly with adequate rest in between their schedules and to carry not more than 32% of their body weight.展开更多
As a stenohaline species,the survival of Sepia pharaonis can be affected by salinity significantly.This study aimed to explore the function of decreasing salinity on the survival of Sepia pharaonis,which can provide a...As a stenohaline species,the survival of Sepia pharaonis can be affected by salinity significantly.This study aimed to explore the function of decreasing salinity on the survival of Sepia pharaonis,which can provide an advanced production guide on the culture of S.pharaonis in the rainy season.Salinity was gradually decreased from 29 to 22 within 48 h to acclimate S.pharaonis to a low-salinity environment.After ten days of breeding under low-salinity of 22,the death rate was high.In this process,changes in tissue and cell structures in the larval liver,biochemical indicators,and osmoregulation-related gene expression were examined.In-terestingly,hepatocytes in the low-salinity group were irregular,had dissolved tissue inclusions,and contained vacuolized cells.There-fore,low salinity caused severe damages at a cellular level that can elevate the mortality rate.A gradual decline in salinity limited the full adaptation of S.pharaonis.Biochemical indicators and osmoregulation-related gene expression changed similarly.For instance,the trend of malondialdehyde(MAD)as a product of lipid peroxidation reflected the degree of damage to the body by free radicals.The antioxidant system of S.pharaonis could cope with oxidative stress caused by the change in salinity to a certain extent.Osmo-regulation-related genes’expression also showed an optimistic result,that is,S.pharaonis responded positively to the change in sali-nity by adjusting the expression of osmoregulation-related genes.Conversely,the increase in mortality at day 10 also proved the weak adaptation capability of S.pharaonis.This study indicated that S.pharaonis can adapt to a low-salinity environment with a li-mited extent.展开更多
In order to identify the optimum period of spring water-restrictive irrigation for winter wheat(Triticum aestivum L.)in the Haihe Plain,China and elucidate its effects on flag leaf senescence and yield formation,field...In order to identify the optimum period of spring water-restrictive irrigation for winter wheat(Triticum aestivum L.)in the Haihe Plain,China and elucidate its effects on flag leaf senescence and yield formation,field experiments were conducted at the Xinji Experimental Station of Hebei Agricultural University from 2016 to 2019 by using different irrigation regimes in spring,including the conventional regime involving two irrigation periods(control(CK),the 3-leaf unfolding stage and the anthesis stage)and a series of single,restrictive irrigation regimes(SRI)comprising irrigation at the 3-leaf unfolding stage(3 LI),4 LI,5 LI,and 6 LI.There are five major findings:(1)The senescence(determined by the green leaf area,GLA)in the 4 LI treatment occurred moderately earlier than that in CK,showed no significant difference with that in 5 LI and 6 LI,and occurred significantly later than that in 3 LI.(2)Compared with other SRI treatments,the GLA value and photosynthetic rate in 4 LI were 14.82 and 20.1%higher,respectively.Microstructural analysis of flag leaf also revealed that the mesophyll cells and chloroplasts were irregularly arranged under drought stress in 3 LI and 6 LI;however,drought stress had minimal negative effects on the microstructure in 4 LI and 5 LI.(3)Postponed irrigation in spring could significantly increase superoxide dismutase(SOD)and catalase(CAT)activities in the early stage of grain filling;however,these activities would subsequently decrease.Among the four SRI treatments,the overall enzyme activities were the highest in 4 LI,and the combined malondialdehyde(MDA)content in flag leaves in 4 LI and 5 LI was 14.5%lower on average than that in 3 LI and 6 LI.(4)The soluble sugar(SS)and proline(Pro)contents in 4 LI were the highest among the four SRI treatments;however,they were lower than those in CK.The abscisic acid(ABA)hormone content in 4 LI and 5 LI was lower than that in 3 LI and 6 LI,respectively,suggesting a smaller drought stress effect in 4 LI and 5 LI.(5)In two growing seasons,there was a larger number of spikes per unit area in 4 LI(i.e.,13.4%higher than that in 5 LI and 6 LI)and the 1000-grain weight in 4 LI was the highest among the four SRI treatments(i.e.,6.0%higher than that in the other three SRI treatments).Therefore,a single restrictive irrigation regime at the 4-leaf unfolding stage is recommended to be effective in slowing down the senescence process of flag leaves and achieving high yield.展开更多
[Objectives]To investigate the effect of low temperature treatment on cotton leaves at the two-leaf stage.[Methods]Two cotton varieties(CN01 and SJB016(low temperature-tolerant))were used as the trial materials.They w...[Objectives]To investigate the effect of low temperature treatment on cotton leaves at the two-leaf stage.[Methods]Two cotton varieties(CN01 and SJB016(low temperature-tolerant))were used as the trial materials.They were treated at 25(CK)and 12℃(low temperature)for 0,3,6,12,24,48 and 72 h,respectively.Then,the changes in the contents of MDA,SS and Pro in the cotton leaves were analyzed.Based on the analysis results,RNA-seq verification was performed.[Results]Two cotton varieties(CN01 and SJB016(low temperature-tolerant))were used as the trial materials.They were treated at 25(CK)and 12℃(low temperature)for 0,3,6,12,24,48 and 72 h,respectively.Then,the changes in the contents of MDA,SS and Pro in the cotton leaves were analyzed.Based on the analysis results,RNA-seq verification was performed.[Conclusions]These genes may play an important role in improving the cold resistance of cotton.展开更多
[Objectives]This study was conducted to clarify the saline-alkali tolerance in seedlings of Lonicera caerulea L.[Methods]The L.caerulea seedling variety,Lanjingling,was used as the test material,and alkaline solution(...[Objectives]This study was conducted to clarify the saline-alkali tolerance in seedlings of Lonicera caerulea L.[Methods]The L.caerulea seedling variety,Lanjingling,was used as the test material,and alkaline solution(NaHCO 3)with different concentration gradients was used for stress treatment to observe physiological effects on L.caerulea seedlings.[Results]L.caerulea seedlings were most affected by alkaline stress at a treatment concentration of 100 mmol/L,and their osmotic substances(proline,soluble sugar,soluble protein)and antioxidant enzymes(CAT,SOD and POD)were higher in content at a concentration of 100 mmol/L compared with the alkaline stresses in this range.The contents were generally higher,and even in the detection of proline,soluble sugar,SOD and POD,the contents of these substances and enzymes reached a peak at 100 mmol/L.The contents of soluble sugar,CAT,SOD,POD and malondialdehyde were generally higher than that of the control check(CK),and the contents of proline and soluble protein in each treatment concentration were generally higher than that of the CK.[Conclusions]The metabolic physiology of L.caerulea seedlings has a certain adaptability to alkaline stress.展开更多
Arbuscular mycorrhizal(AM)fungi distribute widely in natural habits and play a variety of ecological functions.In order to test the physiological response to salt stress mediated by different AM fungi,Viola prionantha...Arbuscular mycorrhizal(AM)fungi distribute widely in natural habits and play a variety of ecological functions.In order to test the physiological response to salt stress mediated by different AM fungi,Viola prionantha was selected as the host,the dominant AM fungus in the rhizosphere of V.philippica growing in Songnen saline-alkali grassland,Rhizophagus irregularis,and their mixtures were used as inoculants,and NaCl stress was applied after the roots were colonized.The results showed that V.philippica could be colonized by AM fungi in the field and the colonization rate ranged from 73.33%to 96.67%,and Claroideoglomus etunicatum was identified as the dominant AM fungi species in the rhizosphere of V.philippica by morphology combined with sequencing for AM fungal AML1/AML2 target.Inoculation with both the species resulted in the formation of mycorrhizal symbiosis(the colonization rate was more than 70%)and AM fungi significantly enhanced plants’tolerance to salt stress of varying magnitude.Higher activity of antioxidant enzymes and augmented levels of proline and other osmoregulators were observed in AM plants.The content of MDA in CK was higher than that in the inoculations with the stress of 100,200,and 250 mM.All indices except soluble protein content and MDA content were significantly correlated with AM fungal colonization indices.The analysis for different AM fungal effects showed that the mixtures and R.irregularis worked even better than C.etunicatum.These results will provide theoretical support for the exploration and screening of salt-tolerant AM fungi species and also for the application of AM-ornamental plants in saline-alkali urban greening.展开更多
Leaf rolling(LR)is one of the defensive mechanisms that plants have developed against adverse environmental conditions.LR is a typical drought response,promoting drought resistance in various gramineae species,includi...Leaf rolling(LR)is one of the defensive mechanisms that plants have developed against adverse environmental conditions.LR is a typical drought response,promoting drought resistance in various gramineae species,including wheat,maize,and rice.Rice cultivation faces the formidable challenge of water deprivation because of its high water requirements,which leads to drought-related symptoms in rice.LR is an important morphological characteristic that plays a key role in controlling water loss during water insufficiency,thereby regulating leaf area and stature,which are crucial agronomic traits determining yield criteria.Bulliform,sclerenchyma,mesophyll,and vascular bundles are the cells that engage in LR and commonly exhibit adaxial or abaxial types of rolling in rice.The specific genes linked to rolling,either adaxially or abaxially,are discussed here.In addition to the factors influencing LR,here is a short review of the morphological,physiological and molecular responses of this adaptation under drought stress.Moreover,this review highlights how LR combats the consequences of drought stress.The eco-physiological and molecular mechanisms underlying this morphological adaptation in rice should be further explored,as they might be useful in dealing with various degrees of drought tolerance.展开更多
Tartary buckwheat(Fagopyrum tataricum)is an important pseudocereal feed crop with medicinal and nutritional value.Drought is one of the main causes of reduced growth and yield in these plants.We investigated the growt...Tartary buckwheat(Fagopyrum tataricum)is an important pseudocereal feed crop with medicinal and nutritional value.Drought is one of the main causes of reduced growth and yield in these plants.We investigated the growth,physiological,and metabolic responses of the widely promoted Tartary buckwheat variety Chuan Qiao No.1 to polyethylene glycol(PEG)-mediated drought stress.Drought significantly decreased shoot length,shoot biomass and relative water content.Root length,malondialdehyde content,electrolyte leakage,activities of superoxide dismutase,peroxidase,catalase and amylase,and contents of soluble sugar,soluble protein and proline were increased by PEG-mediated drought.Untargeted metabolomics analysis identified 32 core metabolites in seedlings subjected to PEG-mediated drought,16 of which increased—including quercetin,isovitexin,cyanidin 3-O-beta-D-glucoside,L-arginine,and glycerophosphocholine,while the other 16 decreased—including 3-methoxytyramine,2,6-diaminopimelic acid,citric acid,UDP-alpha-D-glucose,adenosine,keto-D-fructose.The 32 core metabolites were enriched in 29 metabolic pathways,including lysine biosynthesis,citrate(TCA)cycle,anthocyanin biosynthesis,and aminoacyl-tRNA biosynthesis.Among them,taurine and hypotaurine metabolism,flavor and flavor biosynthesis,indole alkaline biosynthesis,and alanine,aspartate and glutamate metabolism were the four main metabolic pathways affected by drought.Our findings provide new insights into the physiological and metabolic response mechanisms of Tartary buckwheat to drought stress.展开更多
Cerium oxide nanoparticles(CeO_(2) NPs)are likely to have dramatic impacts on plant performances,yet the effects of CeO_(2) NPs on seed germination and seedling growth have not been fully explored.In this study,the se...Cerium oxide nanoparticles(CeO_(2) NPs)are likely to have dramatic impacts on plant performances,yet the effects of CeO_(2) NPs on seed germination and seedling growth have not been fully explored.In this study,the seed germination and seedling growth of subshrub species Vitex negundo under different concentrations of CeO_(2) NPs(low-1 mg/L,medium-100 mg/L,high-500 mg/L)have been discussed.Results showed that:(1)The seed germination rate reduces by 11.25%and 2.5%under the low and medium concentrations of CeO_(2) NPs,respectively,but increased by 7.08%under the high concentration;(2)CeO_(2) NPs had significant effects on the growth traits(root length,shoot height and biomass)of seedlings,being the highest under the medium concentration and the lowest under the highest concentration;(3)The superoxide dismutase activity was the maximum(355.91 U/g),but the protein concentration was the minimum(3.85 ug/mL)under the high concentration of CeO_(2) NPs.Our results indicated that the effects of CeO_(2) NPs on seed germination and seedling growth are concentration-dependency,i.e.,low and medium concentrations inhibited while high concentration promoted seed germination,however,seedling growth showed opposite responses.Therefore,appropriate CeO_(2) NPs concentrations are beneficial to the seed germination and seedling growth of Vitex negundo and improve the physiological performance of seedlings and enhance their adaptability to environmental adversity.展开更多
When studying the thermal adaptation of building occupants,understanding the effects of different thermal experiences on adaptation is necessary,particularly for moderate and severe heat exposure.However,this area has...When studying the thermal adaptation of building occupants,understanding the effects of different thermal experiences on adaptation is necessary,particularly for moderate and severe heat exposure.However,this area has seen limited research.Further,skin temperature,a common parameter for quantifying thermal sensation,may insufficiently reflect the automatic thermoregulation of the human body.This study investigates the effects of long-term heat exposure on the human body using multiple physiological and subjective indexes.Two heat exposure experiments were conducted on healthy male participants from northern and southern China.Participant responses,including skin temperature,heart rate,heart rate variability,blood volume pulse(BVP),subjective thermal comfort thermal sensation,thermal acceptability,and normalized high and low frequency values were collected and compared The results indicated that the subjective responses of northern and southern participants were not significantly different;however,the subjective physiological symptoms and self-reported discomfort of the latter were less than those of the former,indicating that the southern participants had superior heat tolerance.Additionally,the physiological responses of all the participants were largely similar.However,southern participants showed slightly higher normalized high frequency and BVP values,indicating that they have more active vagus nerves and better vasodilation.They also showed a wider acceptable temperature range and better acclimation to heat exposure.Notably,the mean skin temperature could not effectively predict thermal sensation during heat exposure;this was more accurately achieved using the rate of change of skin temperature.These findings suggest that long-term thermal experiences can affect building occupants’thermal adaptability.展开更多
Drought can limit the growth and reduce the yield of crops,but the safe and effective bio-approach to improve the drought resistance of crops is very little.We conducted an experiment in which we monitored the effects...Drought can limit the growth and reduce the yield of crops,but the safe and effective bio-approach to improve the drought resistance of crops is very little.We conducted an experiment in which we monitored the effects of polysaccharide from the endophyte Bionectria sp.Fat6 on the growth of Tartary buckwheat(Fagopyrum tataricum(L.)Gaertn)seedlings under control and drought-stressed conditions by determining gas exchange,photosynthesis parameters,photosynthetic pigment contents,and metabolite accumulation.Results indicated that the polysaccharide from endophyte stimulated plant growth and increased the aboveground biomass,root mass,and root/shoot ratio of Tartary buckwheat.Application of the polysaccharide to drought-stressed plants resulted in a significant increase in the net photosynthetic rate,stomatal conductance,and transpiration rate of Tartary buckwheat and decreased the intercellular CO_(2) concentration.The contents of chlorophyll a,chlorophyll b,chlorophyll a+b,and carotenoids in leaves were higher in polysaccharide-treated seedlings than that in control.Polysaccharide notably increased the soluble protein and proline content and decreased the malondialdehyde content in Tartary buckwheat leaves.The endophytic polysaccharide may protect Tartary buckwheat against drought by improving leaf gas exchange and photosynthetic capacity,and altering concentrations of protective metabolites.Together,these changes may compensate for the negative impacts of drought stress on the growth of Tartary buckwheat.Thus,the polysaccharide from the endophyte Bionectria sp.Fat6 may be an effective biotic elicitor and a promising bio-approach to improve Tartary buckwheat production worldwide.展开更多
Heavy metal(Cu,Mn,Zn,Pb,and Cd)concentrations were measured in the leaves of Sabina chinensis and Platycladus orientalis collected from urban,suburban,and rural sites in Tianjin,China.Photosynthetic pigment contents,r...Heavy metal(Cu,Mn,Zn,Pb,and Cd)concentrations were measured in the leaves of Sabina chinensis and Platycladus orientalis collected from urban,suburban,and rural sites in Tianjin,China.Photosynthetic pigment contents,reactive oxygen species content,malondialdehyde(MDA)content and antioxidant enzyme activity were investigated,providing physiological response parameters.Our comparison of the sites revealed that urbanization significantly influenced the heavy metal concentrations in both plant leaves.At the rural site,both plant leaves exhibited the lowest heavy metal accumulation.The highest Cu,Mn,and Zn concentrations were found in S.chinensis leaves from the urban site;the highest Pb and Cd concentrations were found in P.orientalis leaves from the urban site.These results indicate that the urban site contained larger heavy metal concentrations in the plant leaves that may reflect the anthropogenic emission gradient.It is also found that S.chinensis may be used to monitor airborne heavy metal pollution because it is highly quick response to heavy metals,while P.orientalis may be used for mitigation due to its high resistance.The results of this study can contribute to the development of monitoring and environmental management plans by providing information on sensitive and resistant tree species for city greening in North China.展开更多
To provide theoretical support for study of locust phototactic vision nature,the locust phototactic physiology and visual spectrum effects were investigated by stimulating the visual system using light from an AvaSpec...To provide theoretical support for study of locust phototactic vision nature,the locust phototactic physiology and visual spectrum effects were investigated by stimulating the visual system using light from an AvaSpec fiber-optic spectrometer and Flir thermal imaging system.When light stimulated the locust visual system,the biological photoelectric transformation effect of the visual system caused by photon energy,presented with the higher physiological temperature on the forehead,as tested by the Flir thermal system.After stimulation with light,the different absorption degrees of the vision system on the spectral photons,as tested by the AvaSpec spectrometer,showed that the phototactic response to light had the simultaneous requirements of lighting intensity and time.The absorbing differences of spectral photons by the vision system demonstrated the absorption selectivity under light stimulation,as exhibited by the sensitive absorption of spectral energy at 430 nm,545 nm and 615 nm.Moreover,the higher forehead temperature increment indicated and induced the stronger physiology activity which was the reason that causing the good phototactic response degree of locusts with 30 min light stimulation,and the adaption time was about 60 min.Therefore,only when the visual reaction effect was stimulated to absorb sensitive spectral energy and generate the physiological exciting response could cause the phototactic behavior.展开更多
Traditional environmental control methods for poultry housing which rely solely on environmental factors fall short in meeting thermal and physiological needs of the animals.New methods are needed that factor in the p...Traditional environmental control methods for poultry housing which rely solely on environmental factors fall short in meeting thermal and physiological needs of the animals.New methods are needed that factor in the physiological needs and responses of the animals in order to maximize well-being of the animals and minimize heat stress.Deep body temperature(DBT)has been shown in the literature to be a strong indicator of heat stress,therefore studies are needed that help us gain a deeper understanding of the relationship between this variable and environmental conditions.The aim of this study was to identify the order of the dynamic response of poultry DBT to large step changes in ambient temperature(AT).Temperature steps had to be big enough to take the chickens out of their homeothermic zone.A total of 46 DBT/AT data sets with 23 upward AT steps and 23 downward AT steps were obtained using a biotelemetry system,and involving three chickens.DBT responses of individual chickens to step changes in AT were found to have a 0.88 average Pearson correlation suggesting consistency in chickens’responses to the same stimuli(p<0.0005).The data indicated that DBT responses to AT followed a first order behavior in most cases with an average time constant of 1.6 h,and the curve fitting method was used to validate this observation.There was a 0.88 average correlation between DBT model and measured data(p<0.0005).These results indicate statistical significance in the data used and the model derived from it.In conclusion,it is reasonable to assume that the dynamic response of poultry DBT to large step changes in ambient temperature follows a first order model.Although further studies are needed to more fully derive the model,this study provided a stepping-stone towards gaining a better understanding of the relationship between DBT and AT,therefore taking us one step closer towards making optimal management and risk assessment decisions that are based on physiological needs of the chickens.展开更多
基金This study is supported by the National Key R&D Program of China(No.2018YFD0901004)the Innovation Team Project of Hebei Province Modern Agricultural Industry Technology System(No.HBCT2018170207)+1 种基金the Innovation Center of Hebei Agricultural Products Processing Technology(No.199676183H)the Modern Agricultural Industry Technology System(No.CARS-49).
文摘Given the increased circulation time after fishing,a series of changes take place in live clams,leading to a deterioration in quality even after death.Thus,in this study,we aimed to explore the optimal mode of transportation of clams.The container for holding clams was reformed,and a water circulation temperature control system was established.The physiological responses of clams during anhydrous and watery transportation at two temperatures(4 and 15℃)were investigated based on the aforementioned system.When comparing the transportation patterns after 3 d of transport,a higher survival rate was observed at 4℃(97%)than at 15℃(63%)in the anhydrous transportation groups and a lower survival rate was observed at 4℃(93%)than at 15℃(99%)in the watery transportation groups.In addition,the glycogen content,condition index(CI),and adenylate energy charge(A.E.C)value were higher at4℃((40.87±0.99)mg g^(-1),13.71%±0.50%and 57.45%±1.60%)than at 15℃((30.54±0.81)mg g^(-1),9.09%±0.30%and 43.12%±1.65%)in the anhydrous transportation groups.In the watery transportation groups,a lower glycogen content,CI,and A.E.C.value were observed at 4℃((33.78±0.84)mg g^(-1),9.78%±0.50%and 64.65%±1.25%)than at 15℃((41.53±0.93)mg g^(-1),12.72%±0.83%and 71.58%±1.27%).Results from this study show that anhydrous transportation(4℃)is the optimal transport condition for clams to maintain a high quality and good physiological conditions.Thus,this study will be particularly useful for establishing shellfish transportation systems.
基金supported by the Research Initiation Fund of Hunan Agricultural University(20154/5407419002)the Open Research Fund of the State Key Laboratory of Hybrid Rice,Hunan Hybrid Rice Research Center(2020KF05)+1 种基金the Hunan Science and Technology Major Project(2018NK1010)the Hunan Science and Technology Talents Support Project(2019TJ-Q08)。
文摘Crop yield loss due to soil salinization is an increasing threat to agriculture worldwide.Salt stress drastically affects the growth,development,and grain productivity of rice(Oryza sativa L.),and the improvement of rice tolerance to salt stress is a desirable approach for meeting increasing food demand.The main contributors to salt toxicity at a global scale are Na^(+)and Cl^(-)ions,which affect up to 50%of irrigated soils.Plant responses to salt stress occur at the organismic,cellular,and molecular levels and are pleiotropic,involving(1)maintenance of ionic homeostasis,(2)osmotic adjustment,(3)ROS scavenging,and(4)nutritional balance.In this review,we discuss recent research progress on these four aspects of plant physiological response,with particular attention to hormonal and gene expression regulation and salt tolerance signaling pathways in rice.The information summarized here will be useful for accelerating the breeding of salt-tolerant rice.
基金This research was supported by the National Natural Science Foundation of China(31700639)the National Key Research and Development Program of China(2018YFC0507102,2016YFC0500905).
文摘Drought is one of the most significant natural disasters in the arid and semi-arid areas of China.Populations or plant organs often differ in their responses to drought and other adversities at different growth stages.At present,little is known about the size-and leaf age-dependent differences in the mechanisms of shrub-related drought resistance in the deserts of China.Here,we evaluated the photosynthetic and physiological responses of Artemisia ordosica Krasch.to drought stress using a field experiment in Mu Us Sandy Land,Ningxia Hui Autonomous Region,China in 2018.Rainfall was manipulated by installing outdoor shelters,with four rainfall treatments applied to 12 plots(5 m×5 m).There were four rainfall levels,including a control and rainfall reductions of 30%,50%and 70%,each with three replications.Taking individual crown size as the dividing basis,we measured the responses of A.ordosica photosynthetic and physiological responses to drought at different growth stages,i.e.,large-sized(>0.5 m^(2))and small-sized(≤0.5 m^(2))plants.The leaves of A.ordosica were divided into old leaves and young leaves for separate measurement.Results showed that:(1)under drought stress,the transfer efficiency of light energy captured by antenna pigments to the photosystem II(PSII)reaction center decreased,and the heat dissipation capacity increased simultaneously.To resist the photosynthetic system damage caused by drought,A.ordosica enhanced its free radical scavenging capacity by activating its antioxidant enzyme system;and(2)growth stage and leaf age had effects on the reaction of the photosynthetic system to drought.Small A.ordosica plants could not withstand severe drought stress(70%rainfall reduction),whereas large A.ordosica individuals could absorb deep soil water to ensure their survival in severe drought stressed condition.Under 30%and 50%rainfall reduction conditions,young leaves had a greater ability to resist drought than old leaves,whereas the latter were more resistant to severe drought stress.The response of A.ordosica photosynthetic system reflected the trade-off at different growth stages and leaf ages of photosynthetic production under different degrees of drought.This study provides a more comprehensive and systematic perspective for understanding the drought resistance mechanisms of desert plants.
基金supported by the National Key Research and Development Program of China(2018YFD1000704/2018YFD1000700,2022YFD1201704/2022YFD1201700)the Central Guidance on Local Science and Technology Development Fund of Shandong Province(YDZX2021008)the Agricultural Fine Seed Project of Shandong Province(2021LZGC006)。
文摘Foxtail millet(Setaria italica L.),a member of the Paniceae family,is a temperate and tropical grass species that is widely cultivated on the Eurasian continent.It is Chinese in origin and possesses a small genome,short growth cycle,and strong natural abiotic stress resistance.Elucidating the mechanism of millet tolerance to salt stress is becoming increasingly important with increasing soil salinization limiting crop productivity.The responses and mechanisms of tolerance to salt stress from other model plants such as Arabidopsis and rice,were compared with those from foxtail millet to summarize current research on responses to salt stress.Numerous processes are involved in these processes,including physiological reactions,sensing,signaling,and control at the transcriptional,post-transcriptional,and epigenetic levels.To increase crop productivity and agricultural sustainability,a variety of technologies can be used to investigate how salt tolerance is mediated by physiological and molecular processes in foxtail millet.
基金supported by the National Natural Science Foundation of China (No.30540056)the Natural Science Foundation of Zhejiang Province (No.303461,504135).
文摘Different plants have physiological responses under Al stress,but there is no systematic study to examine physiological responses of herbaceous plants under Al stress.The aim of this study is to investigate the effect of Al on physiological characteristics of four herbaceous plants,which distributed in red soil area in South China,and to analyze the differences in physiological responses to Al stress between the four herbaceous plants.Four herbaceous plants(Pharbitis nil,Cassia occidentlis,Echinochloa colonum and Aeschynomene indica)were used,and the seed germi-nation percentage,the contents of chlorophyll,proline,and malondialdehyde(MDA),membrane permeability(MP),soluble sugar,and activities of peroxides(POD)and cata-lase(CAT)in leaves under five Al^(3+)treatments(0,80,400,2000,and 10000 mg/L)were assayed with the sand culture method.The results showed remarkable effects of Al^(3+)on physiological characteristics of these four herbaceous plants.The seeds of all the four species could not germinate at 10000 mg/L,and the growth of all plants were retarded under the 2000 mg/L Al^(3+)treatment.Compared with the control,2000 mg/L Al^(3+)significantly(P<0.05)reduced the con-tents of chlorophyll a and chlorophyll a+b,and increased the contents of MDA and MP.The content of proline in-creased very significantly(P<0.01)and activities of POD and CAT were depressed.The contents of MDA and MP in leaves of P.nil and A.indica decreased,and the activities of POD and CAT in leaves of the two plants increased under 80 mg/L and 400 mg/L.However,the changes in C.occidentlis leaves were opposite to those of the above two plants.The changes in leaves of E.colonum were similar to those of P.nil and A.indica at 80 mg/L,but were opposite to those at 400 mg/L Al^(3+).It is suggested that plants with higher ac-tivities of POD and CAT,more contents of chlorophyll and proline,and lower contents of MDA and MP consequently improve the tolerance to Al stress under low and middle Al treatments.
基金Supported by the National Major Special Project for the Cultivation of New Genetically Modified Biological Varieties(2018)(Topic ZX08011-003)。
文摘Green foxtail(Setaria viridis)is a notorious weed in corn fields in Heilongjiang Province.To investigate the best method to break the seed dormancy of green foxtail and its physiological response to topramezone,this study selected newly harvested and one-year stored green foxtail seeds as research subjects.The seeds were treated with HCl,Na OH,gibberellic acid(GA),different water temperatures and polyethylene glycol(PEG)to study the seed dormancy and drought resistance of green foxtail.The results showed that newly harvested seeds exhibited dormancy,and treatments with HCl,NaOH and different water temperatures were unable to break the dormancy.Soaking the seeds in GA could overcome dormancy,but the seeds failed to germinate when exposed to 25%PEG concentration.When topramezone was applied at rates of 22.5 and 45.0 g a.i.·hm^(-2)at the 3-leaf and 5-leaf stages,respectively,the chlorophyll content reached the lowest value at 28 days after treatment(DAT).At the 7-leaf stage,the chlorophyll content reached the lowest value at 7 DAT.The activity of 4-hydroxyphenylpy-ruvate dioxygenase(HPPD)enzyme after topramezone application reached the maximum value at 7 DAT for different leaf ages,and the higher the leaf age,the higher the HPPD activity,which was an important factor contributing to the resistance of green foxtail to topramezone.
基金funded through Project No.S&T-09/DIP-251,C3.0 from the Defence Research and Development Organization(DRDO),Ministry of Defence,Government of India
文摘Background: The present study was designed to evaluate load carriage performance at extremely high altitudes with different loads and walking speeds in terms of physiological evaluation. The degree of maximum oxygen consumption changes at high altitudes was also examined.Methods: Twelve Indian Army soldiers were acclimatized at altitudes of 3,505 m and 4,300 m. They walked for 10 minutes on a motorized treadmill at 2.5km/h and 3.5km/h speeds during carrying no loads and three magnitudes of load(10.7kg, 21.4kg, 30kg) at both altitudes. Physiological parameters such as oxygen consumption, energy expenditure, heart rate, and ventilation were recorded for each breath using a gas analyzer. The rating of perceived exertion was also noted after each load carriage session. Maximal oxygen consumption(VO2max) was measured at sea level and the two high altitudes, and respective relative workloads(% of VO2max) were calculated from oxygen consumption. Repeated measure ANOVA was applied to reveal the significant effects of the independent variables.Results: The participants had significant reductions in VO2 max with rising altitude. Marked increases in almost all physiological parameters were observed with increasing load, altitude, and speed. The soldiers expressed heavy perceived exertion levels with higher loads at 3.5km/h at the two high altitudes.Conclusions: Considering the physiological responses, expressions of perceived exertion and changes in relative work load at both of the high altitudes. Indian soldiers are advised to walk slowly with adequate rest in between their schedules and to carry not more than 32% of their body weight.
基金supported by the Ningbo Agricultural Major Projects (No. 201401C1111001)the Foundation of Zhejiang Educational Committee (No. Y2019409 57)sponsored by K.C.Wong Magna Fund in Ningbo University
文摘As a stenohaline species,the survival of Sepia pharaonis can be affected by salinity significantly.This study aimed to explore the function of decreasing salinity on the survival of Sepia pharaonis,which can provide an advanced production guide on the culture of S.pharaonis in the rainy season.Salinity was gradually decreased from 29 to 22 within 48 h to acclimate S.pharaonis to a low-salinity environment.After ten days of breeding under low-salinity of 22,the death rate was high.In this process,changes in tissue and cell structures in the larval liver,biochemical indicators,and osmoregulation-related gene expression were examined.In-terestingly,hepatocytes in the low-salinity group were irregular,had dissolved tissue inclusions,and contained vacuolized cells.There-fore,low salinity caused severe damages at a cellular level that can elevate the mortality rate.A gradual decline in salinity limited the full adaptation of S.pharaonis.Biochemical indicators and osmoregulation-related gene expression changed similarly.For instance,the trend of malondialdehyde(MAD)as a product of lipid peroxidation reflected the degree of damage to the body by free radicals.The antioxidant system of S.pharaonis could cope with oxidative stress caused by the change in salinity to a certain extent.Osmo-regulation-related genes’expression also showed an optimistic result,that is,S.pharaonis responded positively to the change in sali-nity by adjusting the expression of osmoregulation-related genes.Conversely,the increase in mortality at day 10 also proved the weak adaptation capability of S.pharaonis.This study indicated that S.pharaonis can adapt to a low-salinity environment with a li-mited extent.
基金funded by the National Key R&D Program of China(2017YFD0300906)the National Key Technologies R&D Program of China during the 12th Five-Year Plan period(2012BAD04B06)。
文摘In order to identify the optimum period of spring water-restrictive irrigation for winter wheat(Triticum aestivum L.)in the Haihe Plain,China and elucidate its effects on flag leaf senescence and yield formation,field experiments were conducted at the Xinji Experimental Station of Hebei Agricultural University from 2016 to 2019 by using different irrigation regimes in spring,including the conventional regime involving two irrigation periods(control(CK),the 3-leaf unfolding stage and the anthesis stage)and a series of single,restrictive irrigation regimes(SRI)comprising irrigation at the 3-leaf unfolding stage(3 LI),4 LI,5 LI,and 6 LI.There are five major findings:(1)The senescence(determined by the green leaf area,GLA)in the 4 LI treatment occurred moderately earlier than that in CK,showed no significant difference with that in 5 LI and 6 LI,and occurred significantly later than that in 3 LI.(2)Compared with other SRI treatments,the GLA value and photosynthetic rate in 4 LI were 14.82 and 20.1%higher,respectively.Microstructural analysis of flag leaf also revealed that the mesophyll cells and chloroplasts were irregularly arranged under drought stress in 3 LI and 6 LI;however,drought stress had minimal negative effects on the microstructure in 4 LI and 5 LI.(3)Postponed irrigation in spring could significantly increase superoxide dismutase(SOD)and catalase(CAT)activities in the early stage of grain filling;however,these activities would subsequently decrease.Among the four SRI treatments,the overall enzyme activities were the highest in 4 LI,and the combined malondialdehyde(MDA)content in flag leaves in 4 LI and 5 LI was 14.5%lower on average than that in 3 LI and 6 LI.(4)The soluble sugar(SS)and proline(Pro)contents in 4 LI were the highest among the four SRI treatments;however,they were lower than those in CK.The abscisic acid(ABA)hormone content in 4 LI and 5 LI was lower than that in 3 LI and 6 LI,respectively,suggesting a smaller drought stress effect in 4 LI and 5 LI.(5)In two growing seasons,there was a larger number of spikes per unit area in 4 LI(i.e.,13.4%higher than that in 5 LI and 6 LI)and the 1000-grain weight in 4 LI was the highest among the four SRI treatments(i.e.,6.0%higher than that in the other three SRI treatments).Therefore,a single restrictive irrigation regime at the 4-leaf unfolding stage is recommended to be effective in slowing down the senescence process of flag leaves and achieving high yield.
基金Supported by Integration and Demonstration Project of Simple and Efficient Cultivation Technology of Cotton(2020YFD1001000)Special Fund for Construction of Modern Agricultural Industrial Technology SystemProject of Hubei Agricultural Science and Technology Innovation Center(2019-620-000-06)
文摘[Objectives]To investigate the effect of low temperature treatment on cotton leaves at the two-leaf stage.[Methods]Two cotton varieties(CN01 and SJB016(low temperature-tolerant))were used as the trial materials.They were treated at 25(CK)and 12℃(low temperature)for 0,3,6,12,24,48 and 72 h,respectively.Then,the changes in the contents of MDA,SS and Pro in the cotton leaves were analyzed.Based on the analysis results,RNA-seq verification was performed.[Results]Two cotton varieties(CN01 and SJB016(low temperature-tolerant))were used as the trial materials.They were treated at 25(CK)and 12℃(low temperature)for 0,3,6,12,24,48 and 72 h,respectively.Then,the changes in the contents of MDA,SS and Pro in the cotton leaves were analyzed.Based on the analysis results,RNA-seq verification was performed.[Conclusions]These genes may play an important role in improving the cold resistance of cotton.
基金Supported by Tianjin Science and Technology Planning Project(17JCYBJC2980016PTZSTG00020)+1 种基金Jinnan Science and Technology Planning Project of Tianjin City(201802055)Undergraduate Innovation and Enterpreneurship Training Program of Tianjin City(0905).
文摘[Objectives]This study was conducted to clarify the saline-alkali tolerance in seedlings of Lonicera caerulea L.[Methods]The L.caerulea seedling variety,Lanjingling,was used as the test material,and alkaline solution(NaHCO 3)with different concentration gradients was used for stress treatment to observe physiological effects on L.caerulea seedlings.[Results]L.caerulea seedlings were most affected by alkaline stress at a treatment concentration of 100 mmol/L,and their osmotic substances(proline,soluble sugar,soluble protein)and antioxidant enzymes(CAT,SOD and POD)were higher in content at a concentration of 100 mmol/L compared with the alkaline stresses in this range.The contents were generally higher,and even in the detection of proline,soluble sugar,SOD and POD,the contents of these substances and enzymes reached a peak at 100 mmol/L.The contents of soluble sugar,CAT,SOD,POD and malondialdehyde were generally higher than that of the control check(CK),and the contents of proline and soluble protein in each treatment concentration were generally higher than that of the CK.[Conclusions]The metabolic physiology of L.caerulea seedlings has a certain adaptability to alkaline stress.
基金Research was funded by National Natural Science Foundation of China with the Grant No.31601986 and Heilongjiang Postdoctoral Scientific Research Developmental Fund(LBH-Q16005).
文摘Arbuscular mycorrhizal(AM)fungi distribute widely in natural habits and play a variety of ecological functions.In order to test the physiological response to salt stress mediated by different AM fungi,Viola prionantha was selected as the host,the dominant AM fungus in the rhizosphere of V.philippica growing in Songnen saline-alkali grassland,Rhizophagus irregularis,and their mixtures were used as inoculants,and NaCl stress was applied after the roots were colonized.The results showed that V.philippica could be colonized by AM fungi in the field and the colonization rate ranged from 73.33%to 96.67%,and Claroideoglomus etunicatum was identified as the dominant AM fungi species in the rhizosphere of V.philippica by morphology combined with sequencing for AM fungal AML1/AML2 target.Inoculation with both the species resulted in the formation of mycorrhizal symbiosis(the colonization rate was more than 70%)and AM fungi significantly enhanced plants’tolerance to salt stress of varying magnitude.Higher activity of antioxidant enzymes and augmented levels of proline and other osmoregulators were observed in AM plants.The content of MDA in CK was higher than that in the inoculations with the stress of 100,200,and 250 mM.All indices except soluble protein content and MDA content were significantly correlated with AM fungal colonization indices.The analysis for different AM fungal effects showed that the mixtures and R.irregularis worked even better than C.etunicatum.These results will provide theoretical support for the exploration and screening of salt-tolerant AM fungi species and also for the application of AM-ornamental plants in saline-alkali urban greening.
文摘Leaf rolling(LR)is one of the defensive mechanisms that plants have developed against adverse environmental conditions.LR is a typical drought response,promoting drought resistance in various gramineae species,including wheat,maize,and rice.Rice cultivation faces the formidable challenge of water deprivation because of its high water requirements,which leads to drought-related symptoms in rice.LR is an important morphological characteristic that plays a key role in controlling water loss during water insufficiency,thereby regulating leaf area and stature,which are crucial agronomic traits determining yield criteria.Bulliform,sclerenchyma,mesophyll,and vascular bundles are the cells that engage in LR and commonly exhibit adaxial or abaxial types of rolling in rice.The specific genes linked to rolling,either adaxially or abaxially,are discussed here.In addition to the factors influencing LR,here is a short review of the morphological,physiological and molecular responses of this adaptation under drought stress.Moreover,this review highlights how LR combats the consequences of drought stress.The eco-physiological and molecular mechanisms underlying this morphological adaptation in rice should be further explored,as they might be useful in dealing with various degrees of drought tolerance.
基金We acknowledge the Project of National Key Research and Development Program of China(2020YFD1001403)China Agriculture Research System(CARS-07-B-1)+3 种基金Science&Technology Department of Sichuan Province(2022YFQ0041)the National Natural Science Foundation of China(31601260,32160428)Innovative Training Program for College Students(S202111079058)Special Research Fund from Key Laboratory of Coarse Cereal Processing,Ministry of Agriculture and Rural Affairs(2020CC012)to facilitate the research.
文摘Tartary buckwheat(Fagopyrum tataricum)is an important pseudocereal feed crop with medicinal and nutritional value.Drought is one of the main causes of reduced growth and yield in these plants.We investigated the growth,physiological,and metabolic responses of the widely promoted Tartary buckwheat variety Chuan Qiao No.1 to polyethylene glycol(PEG)-mediated drought stress.Drought significantly decreased shoot length,shoot biomass and relative water content.Root length,malondialdehyde content,electrolyte leakage,activities of superoxide dismutase,peroxidase,catalase and amylase,and contents of soluble sugar,soluble protein and proline were increased by PEG-mediated drought.Untargeted metabolomics analysis identified 32 core metabolites in seedlings subjected to PEG-mediated drought,16 of which increased—including quercetin,isovitexin,cyanidin 3-O-beta-D-glucoside,L-arginine,and glycerophosphocholine,while the other 16 decreased—including 3-methoxytyramine,2,6-diaminopimelic acid,citric acid,UDP-alpha-D-glucose,adenosine,keto-D-fructose.The 32 core metabolites were enriched in 29 metabolic pathways,including lysine biosynthesis,citrate(TCA)cycle,anthocyanin biosynthesis,and aminoacyl-tRNA biosynthesis.Among them,taurine and hypotaurine metabolism,flavor and flavor biosynthesis,indole alkaline biosynthesis,and alanine,aspartate and glutamate metabolism were the four main metabolic pathways affected by drought.Our findings provide new insights into the physiological and metabolic response mechanisms of Tartary buckwheat to drought stress.
基金This study was supported by the Science and Technology Innovation Foundation of Henan Agricultural University(30601458)the Scientific Research Foundation for the Doctor of Henan Agriculture University(30500848).
文摘Cerium oxide nanoparticles(CeO_(2) NPs)are likely to have dramatic impacts on plant performances,yet the effects of CeO_(2) NPs on seed germination and seedling growth have not been fully explored.In this study,the seed germination and seedling growth of subshrub species Vitex negundo under different concentrations of CeO_(2) NPs(low-1 mg/L,medium-100 mg/L,high-500 mg/L)have been discussed.Results showed that:(1)The seed germination rate reduces by 11.25%and 2.5%under the low and medium concentrations of CeO_(2) NPs,respectively,but increased by 7.08%under the high concentration;(2)CeO_(2) NPs had significant effects on the growth traits(root length,shoot height and biomass)of seedlings,being the highest under the medium concentration and the lowest under the highest concentration;(3)The superoxide dismutase activity was the maximum(355.91 U/g),but the protein concentration was the minimum(3.85 ug/mL)under the high concentration of CeO_(2) NPs.Our results indicated that the effects of CeO_(2) NPs on seed germination and seedling growth are concentration-dependency,i.e.,low and medium concentrations inhibited while high concentration promoted seed germination,however,seedling growth showed opposite responses.Therefore,appropriate CeO_(2) NPs concentrations are beneficial to the seed germination and seedling growth of Vitex negundo and improve the physiological performance of seedlings and enhance their adaptability to environmental adversity.
基金This study was supported by the National Key Research and Development Program of China during the 13th Five-Year Plan(No.2018YFC07004)the Science Foundation for Young Scholars of Shanxi Province(No.2017JQ5086).
文摘When studying the thermal adaptation of building occupants,understanding the effects of different thermal experiences on adaptation is necessary,particularly for moderate and severe heat exposure.However,this area has seen limited research.Further,skin temperature,a common parameter for quantifying thermal sensation,may insufficiently reflect the automatic thermoregulation of the human body.This study investigates the effects of long-term heat exposure on the human body using multiple physiological and subjective indexes.Two heat exposure experiments were conducted on healthy male participants from northern and southern China.Participant responses,including skin temperature,heart rate,heart rate variability,blood volume pulse(BVP),subjective thermal comfort thermal sensation,thermal acceptability,and normalized high and low frequency values were collected and compared The results indicated that the subjective responses of northern and southern participants were not significantly different;however,the subjective physiological symptoms and self-reported discomfort of the latter were less than those of the former,indicating that the southern participants had superior heat tolerance.Additionally,the physiological responses of all the participants were largely similar.However,southern participants showed slightly higher normalized high frequency and BVP values,indicating that they have more active vagus nerves and better vasodilation.They also showed a wider acceptable temperature range and better acclimation to heat exposure.Notably,the mean skin temperature could not effectively predict thermal sensation during heat exposure;this was more accurately achieved using the rate of change of skin temperature.These findings suggest that long-term thermal experiences can affect building occupants’thermal adaptability.
基金This work was funded by National Key R&D Program of China(Grant No.2019YFD1001302/2019YFD1001300)Supported by National Natural Science Foundation of China(31771716+2 种基金3160126031701358)the earmarked fund for China Agriculture Research System(CARS-07-02A).
文摘Drought can limit the growth and reduce the yield of crops,but the safe and effective bio-approach to improve the drought resistance of crops is very little.We conducted an experiment in which we monitored the effects of polysaccharide from the endophyte Bionectria sp.Fat6 on the growth of Tartary buckwheat(Fagopyrum tataricum(L.)Gaertn)seedlings under control and drought-stressed conditions by determining gas exchange,photosynthesis parameters,photosynthetic pigment contents,and metabolite accumulation.Results indicated that the polysaccharide from endophyte stimulated plant growth and increased the aboveground biomass,root mass,and root/shoot ratio of Tartary buckwheat.Application of the polysaccharide to drought-stressed plants resulted in a significant increase in the net photosynthetic rate,stomatal conductance,and transpiration rate of Tartary buckwheat and decreased the intercellular CO_(2) concentration.The contents of chlorophyll a,chlorophyll b,chlorophyll a+b,and carotenoids in leaves were higher in polysaccharide-treated seedlings than that in control.Polysaccharide notably increased the soluble protein and proline content and decreased the malondialdehyde content in Tartary buckwheat leaves.The endophytic polysaccharide may protect Tartary buckwheat against drought by improving leaf gas exchange and photosynthetic capacity,and altering concentrations of protective metabolites.Together,these changes may compensate for the negative impacts of drought stress on the growth of Tartary buckwheat.Thus,the polysaccharide from the endophyte Bionectria sp.Fat6 may be an effective biotic elicitor and a promising bio-approach to improve Tartary buckwheat production worldwide.
基金supported by the National Key Research and Development Program of China(No.2017YFE0127700)the State Key Laboratory of Urban&Regional Ecology(No.SKLURE2017-2-4)。
文摘Heavy metal(Cu,Mn,Zn,Pb,and Cd)concentrations were measured in the leaves of Sabina chinensis and Platycladus orientalis collected from urban,suburban,and rural sites in Tianjin,China.Photosynthetic pigment contents,reactive oxygen species content,malondialdehyde(MDA)content and antioxidant enzyme activity were investigated,providing physiological response parameters.Our comparison of the sites revealed that urbanization significantly influenced the heavy metal concentrations in both plant leaves.At the rural site,both plant leaves exhibited the lowest heavy metal accumulation.The highest Cu,Mn,and Zn concentrations were found in S.chinensis leaves from the urban site;the highest Pb and Cd concentrations were found in P.orientalis leaves from the urban site.These results indicate that the urban site contained larger heavy metal concentrations in the plant leaves that may reflect the anthropogenic emission gradient.It is also found that S.chinensis may be used to monitor airborne heavy metal pollution because it is highly quick response to heavy metals,while P.orientalis may be used for mitigation due to its high resistance.The results of this study can contribute to the development of monitoring and environmental management plans by providing information on sensitive and resistant tree species for city greening in North China.
基金the National Natural Science Foundation of China(Grant No.50775412)the 2012 Public Welfare Industry(Agriculture)Special Funds for Scientific Research Projects(Grant No.201203025).
文摘To provide theoretical support for study of locust phototactic vision nature,the locust phototactic physiology and visual spectrum effects were investigated by stimulating the visual system using light from an AvaSpec fiber-optic spectrometer and Flir thermal imaging system.When light stimulated the locust visual system,the biological photoelectric transformation effect of the visual system caused by photon energy,presented with the higher physiological temperature on the forehead,as tested by the Flir thermal system.After stimulation with light,the different absorption degrees of the vision system on the spectral photons,as tested by the AvaSpec spectrometer,showed that the phototactic response to light had the simultaneous requirements of lighting intensity and time.The absorbing differences of spectral photons by the vision system demonstrated the absorption selectivity under light stimulation,as exhibited by the sensitive absorption of spectral energy at 430 nm,545 nm and 615 nm.Moreover,the higher forehead temperature increment indicated and induced the stronger physiology activity which was the reason that causing the good phototactic response degree of locusts with 30 min light stimulation,and the adaption time was about 60 min.Therefore,only when the visual reaction effect was stimulated to absorb sensitive spectral energy and generate the physiological exciting response could cause the phototactic behavior.
文摘Traditional environmental control methods for poultry housing which rely solely on environmental factors fall short in meeting thermal and physiological needs of the animals.New methods are needed that factor in the physiological needs and responses of the animals in order to maximize well-being of the animals and minimize heat stress.Deep body temperature(DBT)has been shown in the literature to be a strong indicator of heat stress,therefore studies are needed that help us gain a deeper understanding of the relationship between this variable and environmental conditions.The aim of this study was to identify the order of the dynamic response of poultry DBT to large step changes in ambient temperature(AT).Temperature steps had to be big enough to take the chickens out of their homeothermic zone.A total of 46 DBT/AT data sets with 23 upward AT steps and 23 downward AT steps were obtained using a biotelemetry system,and involving three chickens.DBT responses of individual chickens to step changes in AT were found to have a 0.88 average Pearson correlation suggesting consistency in chickens’responses to the same stimuli(p<0.0005).The data indicated that DBT responses to AT followed a first order behavior in most cases with an average time constant of 1.6 h,and the curve fitting method was used to validate this observation.There was a 0.88 average correlation between DBT model and measured data(p<0.0005).These results indicate statistical significance in the data used and the model derived from it.In conclusion,it is reasonable to assume that the dynamic response of poultry DBT to large step changes in ambient temperature follows a first order model.Although further studies are needed to more fully derive the model,this study provided a stepping-stone towards gaining a better understanding of the relationship between DBT and AT,therefore taking us one step closer towards making optimal management and risk assessment decisions that are based on physiological needs of the chickens.