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Spraying Arginine at 5 Days before Harvest Delays Postharvest Broccoli Senescence via Nutrient Accumulation
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作者 SUN Yupeng CHEN Ying +4 位作者 SHANG Qingwen GUO Yanyin ZHANG Yuxiao WANG Yunqiao XUE Qingyue 《食品科学》 EI CAS 北大核心 2025年第1期131-141,共11页
To determine the effects of preharvest arginine spraying on the nutritional level of broccoli and the mechanism of action of arginine in improving the storage quality of broccoli,arginine spraying(5 mmol/L)was conduct... To determine the effects of preharvest arginine spraying on the nutritional level of broccoli and the mechanism of action of arginine in improving the storage quality of broccoli,arginine spraying(5 mmol/L)was conducted at 0,1,3,and 5 days before harvest.The appearance,respiration rate,mass-loss rate,electrolyte leakage,glucosinolate,ascorbic acid,total phenol,total flavonoid,total sugar and sucrose contents,and sucrose phosphate synthase(SPS),invertase(INV),sucrose synthase synthesis(SSS)and cleavage(SSC)activities of broccoli samples were observed after 0,2,4,6,8,and 10 days of storage.The results showed that spraying arginine at 5 days preharvest(5-ARG)helped to inhibit broccoli respiration during storage,delay electrolyte leakage,and maintain broccoli color.Furthermore,during the growth stage,total sugar accumulation was higher in the 5-ARG group.In addition,during the storage period,sucrose synthesis was accelerated,while sucrose cleavage was inhibited,resulting in more sucrose retention in postharvest broccoli.In conclusion,5-ARG resulted in the accumulation of more nutrients during the growth process and effectively delayed the quality decline during storage,thereby prolonging the shelf life of broccoli.Therefore,this study provides a theoretical basis for improving postharvest storage characteristics of broccoli through preharvest treatments. 展开更多
关键词 ARGININE BROCCOLI preharvest spraying nutrient accumulation storage quality postharvest senescence
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Analysis of the Trend in the Consumption of Psychoactive Substances in Senegal from 2018 to 2022
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作者 Jean Augustin Diégane Tine Kadidiatou Diarra +1 位作者 Amadou Ibra Diallo Ibrahima Seck 《Open Journal of Epidemiology》 2025年第1期36-49,共14页
Purpose: The aim of the study was to investigate the profile of psychoactive substance users in Senegal from 2018 to 2022. Methodology: These were retrospective descriptive studies of patient consultation and hospital... Purpose: The aim of the study was to investigate the profile of psychoactive substance users in Senegal from 2018 to 2022. Methodology: These were retrospective descriptive studies of patient consultation and hospitalization records in the 17 psychiatric and addictology care centers in Senegal from 2018 to 2022. This was an exhaustive survey. All usable consultation and hospitalization registers were included in the study. Non-usable consultation and hospitalization registers were not included. Data were collected from January 1 to December 31 of each respective year. Data were cleaned using Excel before analysis. R software version 4.3.3 was used for analysis. Results: Between 2018 and 2022, 26,029 patients were registered in mental health facilities in Senegal. The Fann Psychiatry Department (CHNU Fann) admitted 23.2% of patients and the Thiaroye National Psychiatric Hospital registered 17.6% of drug users. For the year 2019, we found 8259 and in 2021, we had 6607 patients. The male gender was more represented with 14,750 patients, or 90.9%. The age group [25 - 34] was the majority (7013 patients or 39.5%). The majority of patients (17,425 patients, or 84.6%) were followed as outpatients. The drugs were mainly inhaled (96.7%). The most consumed substance was cannabis with 8847 patients, or 54.2%. Withdrawal was the main reason for treatment, 11,614 patients, or 85.7%. Conclusion: In the light of the results of our study, we can say that the use of psychoactive substances is a real public health and development problem in Senegal. The peaks in psychoactive substance consumption preceded the peaks in psychiatric care centers, so we need to promote information, education and communication on the harmful effects of psychoactive substance consumption among the population in general and young people in particular, in order to safeguard the country’s development. 展开更多
关键词 CONSUMPTION substance Psychoactive DRUGS Senegal
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Occupational Stress and Psychoactive Substance Use: A Study of Cable Factory Workers in Morocco
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作者 Laila Essfioui 《Open Journal of Medical Psychology》 2025年第1期1-18,共18页
Work-related stress has become an alarming reality that continues to intensify over the past decades. The pressure exerted by the work environment demands the utilization of defensive and coping strategies to deal wit... Work-related stress has become an alarming reality that continues to intensify over the past decades. The pressure exerted by the work environment demands the utilization of defensive and coping strategies to deal with it. Our study aims to explore the relationship between professional stress factors, stress symptoms, and the consumption of psychoactive substances as a defensive and coping strategy deployed to address psychological distress at work. A qualitative and quantitative study was conducted with a sample of 405 employees from a wiring manufacturing. The main professional stress factors identified were concentration, overload, long working hours, and monotony, which showed a significant correlation with PAS consumption. Women were found to be more affected by stress and tended to consume more sedatives. Among the respondents, 21.98% reported PAS consumption, with tobacco being the most commonly used (M = 2.66), followed by alcohol (M = 1.94), cannabis (M = 1.79), and sedatives (M = 1.45). There was a significant positive correlation between PAS consumption and stress symptoms {tobacco (r = 0.232*), alcohol (r = 0.305**), cannabis (r = 0.389**)}. 展开更多
关键词 Professional Stress Psychoactive substance SUFFERING COPING
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Dietary supplementation with pterostilbene activates the PI3K‑AKT‑mTOR signalling pathway to alleviate progressive oxidative stress and promote placental nutrient transport
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作者 Mingming Cao Liyun Bai +4 位作者 Haoyun Wei Yantong Guo Guodong Sun Haoyang Sun Baoming Shi 《Journal of Animal Science and Biotechnology》 2025年第1期388-407,共20页
Background Progressive oxidative stress easily occurs as a result of a gradual increase in the intensity of maternal metabolism due to rapid foetal development and increased intensity of lactation.However,studies on t... Background Progressive oxidative stress easily occurs as a result of a gradual increase in the intensity of maternal metabolism due to rapid foetal development and increased intensity of lactation.However,studies on the effects of processive oxidative stress on nutrient transport in the placenta have received little attention.The present study was conducted on sows at 85 days of gestation to study the effects of pterostilbene(PTE)on maternal oxidative stress status and placental nutrient transport.Results PTE increased the antioxidant capacity and immunoglobulin content in mothers’blood and milk,reduced the level of inflammatory factors,and improved the nutrient content of milk.PTE also reduced sow backfat loss and the number of weak sons,and increased piglet weaning weight and total weaning litter weight.We subsequently found that PTE enhanced placental glucose and fatty acid transport and further affected glycolipid metabolism by increasing the expression of LAL,PYGM,and Gbe-1,which activated the PI3K phosphorylation pathway.Moreover,PTE addition altered the relative abundance of the Firmicutes,Proteobacteria,Parabacillus,and Bacteroidetes-like RF16 groups in sow faeces.PTE increased the levels of acetate,propionate,butyrate and isovalerate in the faeces.Conclusions These findings reveal that the addition of PTE during pregnancy and lactation mitigates the effects of processive oxidative stress on offspring development by altering maternal microbial and placental nutrient trans-port capacity. 展开更多
关键词 nutrient transporters PLACENTA Progressive oxidative stress PTEROSTILBENE SOWS
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Effects of biological soil crusts on plant growth and nutrient dynamics in the Minqin oasis-desert ecotone,Northwest China
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作者 KANG Jianjun YANG Fan +1 位作者 ZHANG Dongmei DING Liang 《Journal of Arid Land》 2025年第1期130-143,共14页
Biological soil crusts(BSCs)play crucial roles in improving soil fertility and promoting plants settlement and reproduction in arid areas.However,the specific effects of BSCs on growth status and nutrient accumulation... Biological soil crusts(BSCs)play crucial roles in improving soil fertility and promoting plants settlement and reproduction in arid areas.However,the specific effects of BSCs on growth status and nutrient accumulation of plants are still unclear in different arid areas.This study analyzed the effects of three different BSCs treatments(without crust(WC),intact crust(IC),and broken crust(BC))on the growth,inorganic nutrient absorption,and organic solute synthesis of three typical desert plants(Grubovia dasyphylla(Fisch.&C.A.Mey.)Freitag&G.Kadereit,Nitraria tangutorum Bobrov,and Caragana koraiensis Kom.)in the Minqin desert-oasis ecotone of Northwest China.Results showed that the effects of three BSCs treatments on seed emergence and survival of three plants varied with seed types.The IC treatment significantly hindered the emergence and survival of seeds,while the BC treatment was more conducive to seed emergence and survival of plants.BSCs significantly promoted the growth of three plants,but their effects on plant growth varied at different stages of the growth.Briefly,the growth of G.dasyphylla was affected by BSCs in early stage,but the effects on the growth of G.dasyphylla significantly weakened in the middle and late stages.However,the growth of N.tangutorum and C.koraiensis only showed differences at the middle and late stages,with a significant enhancement in growth.Analysis of variance showed that BSCs,plant species,growth period,and their interactions had significant effects on the biomass and root:shoot ratio of three plants.BSC significantly affected the nutrients absorption and organic solute synthesis in plants.Specifically,BSCs significantly promoted nitrogen(N)absorption in plants and increased plant adaptability in N poor desert ecosystems,but had no significant effects on phosphorus(P)absorption.The effects of BSCs on inorganic nutrient absorption and organic solute synthesis in plants varied significantly among different plant species.The results suggest that BSCs have significant effects on the growth and nutrient accumulation of desert plants,which will provide theoretical basis for exploring the effects of BSCs on desert plant diversity,biodiversity conservation,and ecosystem management measures in arid and semi-arid areas. 展开更多
关键词 biological soil crusts(BSCs) desert oasis desert plants GROWTH nutrient accumulation
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Microbial community and dynamic changes of extracellular polymeric substances in relation to plastisphere of disposable surgical masks in natural aquatic environment
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作者 Ling ZHANG Yuxin ZHOU +6 位作者 Zixian ZHU Feifei YAN Luxi TAN Chunyan WEI Zihao WANG Qingfeng CHEN Ying ZHANG 《Journal of Oceanology and Limnology》 2025年第2期502-514,共13页
In the context of global COVID-19 epidemic preparedness,the extensive use of disposable surgical masks(DSM)may lead to its emergence as a main new source of microplastics in the environment.Nowadays,DSMs have become a... In the context of global COVID-19 epidemic preparedness,the extensive use of disposable surgical masks(DSM)may lead to its emergence as a main new source of microplastics in the environment.Nowadays,DSMs have become a non-negligible source of plastic waste in aquatic environment,however,less research has been done on DSM after biofilm colonization in freshwater environment.The study investigated the microbial community of DSM-associated biofilms by 16S rRNA gene sequencing.Analysis of the microbial community in the middle and inner/outer layers of the DSM showed that the middle layer was different from the remaining two layers and that potential pathogens were enriched only in the middle layer of the DSM.Herein,we focused on the middle layer and explored the characterization properties and extracellular polymeric substances(EPS)components changes during biofilm formation.The results showed that the EPS components varied with the biofilm incubation time.As the formation of biofilm,the protein(PN)and polysaccharide(PS)in EPS showed an overall increasing trend,and the growth of PS was well synchronized with PN.Three fluorescent components of EPS were determined by the three-dimensional excitation emission matrix(3D-EEM),including humic acid-like,fulvic acid-like,and aromatic protein-like components.The percentage of fluorescent components varied with increasing biofilm development time and then stabilized.Fourier transform infrared spectroscopy(FTIR)characterization results elucidated the emergence of oxygen-containing functional groups during biofilm formation.Moreover,the hydrophilicity increased with biofilm development.In conclusion,the environmental behavior and ecological risks of DSM in aquatic environment deserve urgent attention in future studies. 展开更多
关键词 BIOFILM disposable surgical masks(DSM) extracellular polymeric substances(EPS) microbial community plastisphere
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Correlative Analysis between Contents of Nutrients and Secondary Substances in Damaged Pinus massoniana Needles and Population Parameters of Dendrolimus kikuchii(Lepidoptera:Lasiocampidae) 被引量:1
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作者 Tong Wengang Chen Shunli +1 位作者 Zhou Suo Chen Delan 《Plant Diseases and Pests》 CAS 2014年第4期13-19,25,共8页
In order to explore the effects of chemical substances changes in damaged masson pine (Pinus massoniana) needles on population dynamics of Dendroli- mus kikuchii, D. kikuchii larvae were reat~ with P. massoniana nee... In order to explore the effects of chemical substances changes in damaged masson pine (Pinus massoniana) needles on population dynamics of Dendroli- mus kikuchii, D. kikuchii larvae were reat~ with P. massoniana needles with different damage degrees (mild, moderate and severe), and its population parame- ters and contents of nutrients and secondary substances in damaged P. massoniana needles were measured, and the integrated correlation coefficient was adopted for data analysis. The results showed that with the damage degree aggravating, flavones in needles increased accordingly, while contents of soluble sugars, polysaeeha- rides and proteins decreased. The average developmental duration and mortality of D. kikuchii larvae increased with the damage degree increasing. No significant correlation was found between the changes in contents of tannins or total phenols and the developmental duration or mortality of each instar larvae. There were signif- icant direct and integrated correlations between contents of nutrients and secondary substances of P. massoniana needles and the developmental duration or mortality of each instar larvae except the 6'h instar larvae. With the damage degree increasing, all parameters of D. kikuchii population including body weight of the 7~ instar larvae, average feeding capacity of larvae, pupal weight, pupation rate, female ratio and fecundity decreased. No significant correlation was found between the changes in contents of tannins or total phenols and population parameters of D. kikuchii larvae. The results suggest that the contents of nutrients and secondary sub- stances in P. ,mssoniana needles dramatically influenced the population parameters of D. kikuchii, and the importance from high to low successively was soluble sugars 〉 proteins 〉 polysaccharides 〉 flavones. Contents of tannins and total phenols seemed to have little influence. 展开更多
关键词 Dendrolimus kikuchii Pinus massoniana nutrientS Secondary substances Population parameters Integrated correlation coefficient
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Investigations on the Thermodynamic Stability and Availability of Nutrients for Plants by Humic Substances Extracted from Peat Samples
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作者 Camila De Almeida Melo Lilian Karla De Oliveira Bruno Barboza Cunha Leonardo Femandes Fraceto Andre Henrique Rosa 《Journal of Environmental Science and Engineering(A)》 2015年第7期367-377,共11页
This work evaluated the complexation capacity, exchange constants and availability of micronutrients for plants and humic substances extracted from peat samples. Samples of humic substances extracted from two tropical... This work evaluated the complexation capacity, exchange constants and availability of micronutrients for plants and humic substances extracted from peat samples. Samples of humic substances extracted from two tropical peats (HS-P1 and HS-P2) were enriched with the micronutrients Cu(II), Co(II), Fe(II), Mn(II), Ni(II) and Zn(II) and the parameters for formation of the complexes (HS-N) were evaluated at different pH. The Scatchard model was used to calculate the maximum complexation capacity and the nutrient availability was studied using exchange capacity experiments based on ultrafiltration procedure. The optimum pH for complexation was 4.5 and the order of affinity was: Fe(II) 〉 Cu(II) 〉 Co(II) 〉 Mn(II) = Ni(II) 〉 Zn(II). The maximum complexation capacity reached 56.8 mg·g-1 Fe of HS-P1 (the highest) and 1.7 mg.g1 Zn of HS-P2 (the slightest). The exchange experiments showed that HS-P-Fe complexes were formed preferentially. The least stable complex was formed with Zn, which was therefore, more easily available. The results contribute to understand the behavior and availability of some nutrients in soils. 展开更多
关键词 Peat humic substances COMPLEXATION nutrient availability exchange capacity soil
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Effects of the kinetic pattern of dietary glucose release on nitrogen utilization, the portal amino acid profile, and nutrient transporter expression in intestinal enterocytes in piglets 被引量:2
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作者 Zexi Li Yunfei Li +6 位作者 Yufei Zhao Guifu Wang Rujie Liu Yue Li Qamar Aftab Zewei Sun Qingzhen Zhong 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期2106-2121,共16页
Background Promoting the synchronization of glucose and amino acid release in the digestive tract of pigs could effectively improve dietary nitrogen utilization.The rational allocation of dietary starch sources and th... Background Promoting the synchronization of glucose and amino acid release in the digestive tract of pigs could effectively improve dietary nitrogen utilization.The rational allocation of dietary starch sources and the exploration of appropriate dietary glucose release kinetics may promote the dynamic balance of dietary glucose and amino acid supplies.However,research on the effects of diets with different glucose release kinetic profiles on amino acid absorption and portal amino acid appearance in piglets is limited.This study aimed to investigate the effects of the kinetic pattern of dietary glucose release on nitrogen utilization,the portal amino acid profile,and nutrient transporter expression in intestinal enterocytes in piglets.Methods Sixty-four barrows(15.00±1.12 kg)were randomly allotted to 4 groups and fed diets formulated with starch from corn,corn/barley,corn/sorghum,or corn/cassava combinations(diets were coded A,B,C,or D respectively).Protein retention,the concentrations of portal amino acid and glucose,and the relative expression of amino acid and glucose transporter m RNAs were investigated.In vitro digestion was used to compare the dietary glucose release profiles.Results Four piglet diets with different glucose release kinetics were constructed by adjusting starch sources.The in vivo appearance dynamics of portal glucose were consistent with those of in vitro dietary glucose release kinetics.Total nitrogen excretion was reduced in the piglets in group B,while apparent nitrogen digestibility and nitrogen retention increased(P<0.05).Regardless of the time(2 h or 4 h after morning feeding),the portal total free amino acids content and contents of some individual amino acids(Thr,Glu,Gly,Ala,and Ile)of the piglets in group B were significantly higher than those in groups A,C,and D(P<0.05).Cluster analysis showed that different glucose release kinetic patterns resulted in different portal amino acid patterns in piglets,which decreased gradually with the extension of feeding time.The portal His/Phe,Pro/Glu,Leu/Val,Lys/Met,Tyr/Ile and Ala/Gly appeared higher similarity among the diet treatments.In the anterior jejunum,the glucose transporter SGLT1 was significantly positively correlated with the amino acid transporters B0AT1,EAAC1,and CAT1.Conclusions Rational allocation of starch resources could regulate dietary glucose release kinetics.In the present study,group B(corn/barley)diet exhibited a better glucose release kinetic pattern than the other groups,which could affect the portal amino acid contents and patterns by regulating the expression of amino acid transporters in the small intestine,thereby promoting nitrogen deposition in the body,and improving the utilization efficiency of dietary nitrogen. 展开更多
关键词 Glucose release kinetics Nitrogen utilization nutrient transporter PIGLET
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Response of soil nutrients to terracing and environmental factors in the Loess Plateau of China 被引量:1
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作者 Die Chen Wei Wei +2 位作者 Liding Chen Bojun Ma Hao Li 《Geography and Sustainability》 CSCD 2024年第2期230-240,共11页
Terracing is a widely adopted agricultural practice in mountainous regions around the world that aims to conserve soil and water resources.Soil nutrients play a crucial role in determining soil quality,particularly in... Terracing is a widely adopted agricultural practice in mountainous regions around the world that aims to conserve soil and water resources.Soil nutrients play a crucial role in determining soil quality,particularly in landscapes prone to drought.They are influenced by factors such as land-use type,slope aspect,and altitude.In this study,we sought to examine the impact of terracing on soil nutrients(soil organic content(SOC),total nitrogen(TN),nitrate-nitrogen(NO_(3)^(-)-N),ammonium nitrogen(NH_(4)^(+)-N),total phosphorus(TP),available phosphorus(AP),total potassium(TK),and available potassium(AK))and how they vary with environmental factors in the Chinese Loess Plateau.During the growing season,we collected 540 soil samples from the 0 to 100 cm soil layer across five major land-use types,different slope aspects,and varying altitudes.Additionally,a meta-analysis of literature data further corroborated the effective accumulation of soil nutrients through terracing in the Loess Plateau.Our findings are as follows:(1)Terraced fields,regardless of land-use type,showed a significant improvement in SOC and TN content.(2)Soil nutrient contents within terraced fields were predominantly higher on sunny slopes.(3)Terraces at lower altitudes are characterized by elevated SOC concentrations.(4)A meta-analysis of literature data pertaining to terracing and soil nutrients in this region confirmed the effective accumulation of soil nutri-ents through terracing.The elucidated outcomes of this study offer a profound theoretical underpinning for the accurate planning and management of terraces,the scientific utilization of land resources,and the enhancement of land productivity. 展开更多
关键词 TERRACE Soil nutrients Land-use Slope aspect ALTITUDE Loess Plateau
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Effect of wall-disruption on nutrient composition and in vitro digestion of camellia and lotus bee pollens 被引量:1
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作者 Yuan Yuan Shun Zhong +3 位作者 Zeyuan Deng Guangyan Li Jinwu Zhang Hongyan Li 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1567-1577,共11页
The nutrient digestion,absorption and biological activity of bee pollen may be limited due to the complex pollen wall.Here,the effect of superfine grinding technology on the release of nutrients from bee pollen were i... The nutrient digestion,absorption and biological activity of bee pollen may be limited due to the complex pollen wall.Here,the effect of superfine grinding technology on the release of nutrients from bee pollen were investigated,and their antioxidant activities and in vitro digestion were explored in this study.Results showed that the content of nutrients in bee pollen increased after wall disruption.Among them,fat content increased by 22.55%-8.31%,protein content increased by 0.54%-4.91%,starch content increased by 36.31%-48.64%,soluble sugar content increased by 20.57%-29.67%,total phenolic acid content increased by 11.73%-86.98%and total flavonoids content increased by 14.29%-24.79%.At the same time,the antioxidant activity increased by 14.84%-46.00%.Furthermore,the active components such as phenolic compounds in the wall-disruption bee pollen were more readily to be released during the in vitro digestion,and easier to be absorbed because of their higher bioaccessibility.Antioxidant activities during in vitro digestion were also improved in walldisruption bee pollen.These findings provide evidence that bee pollen wall disruption was suggested,thus,it is more conducive to exerting the value of bee pollen in functional foods. 展开更多
关键词 Bee pollen nutrientS Wall disruption Phenolic compounds In vitro digestion
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Dynamics and genetic regulation of macronutrient concentrations during grain development in maize 被引量:1
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作者 Pengcheng Li Shuangyi Yin +7 位作者 Yunyun Wang Tianze Zhu Xinjie Zhu Minggang Ji Wenye Rui Houmiao Wang Chenwu Xu Zefeng Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期781-794,共14页
Nitrogen(N), phosphorus(P), and potassium(K) are essential macronutrients that are crucial not only for maize growth and development, but also for crop yield and quality. The genetic basis of macronutrient dynamics an... Nitrogen(N), phosphorus(P), and potassium(K) are essential macronutrients that are crucial not only for maize growth and development, but also for crop yield and quality. The genetic basis of macronutrient dynamics and accumulation during grain filling in maize remains largely unknown. In this study, we evaluated grain N, P, and K concentrations in 206 recombinant inbred lines generated from a cross of DH1M and T877 at six time points after pollination. We then calculated conditional phenotypic values at different time intervals to explore the dynamic characteristics of the N, P, and K concentrations. Abundant phenotypic variations were observed in the concentrations and net changes of these nutrients. Unconditional quantitative trait locus(QTL) mapping revealed 41 non-redundant QTLs, including 17, 16, and 14 for the N, P, and K concentrations, respectively. Conditional QTL mapping uncovered 39 non-redundant QTLs related to net changes in the N, P, and K concentrations. By combining QTL, gene expression, co-expression analysis, and comparative genomic data, we identified 44, 36, and 44 candidate genes for the N, P, and K concentrations, respectively, including GRMZM2G371058 encoding a Doftype zinc finger DNA-binding family protein, which was associated with the N concentration, and GRMZM2G113967encoding a CBL-interacting protein kinase, which was related to the K concentration. The results deepen our understanding of the genetic factors controlling N, P, and K accumulation during maize grain development and provide valuable genes for the genetic improvement of nutrient concentrations in maize. 展开更多
关键词 MAIZE nutrient concentration unconditional QTL mapping conditional QTL mapping dynamic trait
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Subsoil tillage enhances wheat productivity,soil organic carbon and available nutrient status in dryland fields 被引量:1
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作者 Qiuyan Yan Linjia Wu +6 位作者 Fei Dong Shuangdui Yan Feng Li Yaqin Jia Jiancheng Zhang Ruifu Zhang Xiao Huang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期251-266,共16页
Tillage practices during the fallow period benefit water storage and yield in dryland wheat crops.However,there is currently no clarity on the responses of soil organic carbon(SOC),total nitrogen(TN),and available nut... Tillage practices during the fallow period benefit water storage and yield in dryland wheat crops.However,there is currently no clarity on the responses of soil organic carbon(SOC),total nitrogen(TN),and available nutrients to tillage practices within the growing season.This study evaluated the effects of three tillage practices(NT,no tillage;SS,subsoil tillage;DT,deep tillage)over five years on soil physicochemical properties.Soil samples at harvest stage from the fifth year were analyzed to determine the soil aggregate and aggregate-associated C and N fractions.The results indicated that SS and DT improved grain yield,straw biomass and straw carbon return of wheat compared with NT.In contrast to DT and NT,SS favored SOC and TN concentrations and stocks by increasing the soil organic carbon sequestration rate(SOCSR)and soil nitrogen sequestration rate(TNSR)in the 0-40 cm layer.Higher SOC levels under SS and NT were associated with greater aggregate-associated C fractions,while TN was positively associated with soluble organic nitrogen(SON).Compared with DT,the NT and SS treatments improved soil available nutrients in the 0-20 cm layer.These findings suggest that SS is an excellent practice for increasing soil carbon,nitrogen and nutrient availability in dryland wheat fields in North China. 展开更多
关键词 TILLAGE dryland wheat fields soil aggregate size soil nutrients soil carbon and nitrogen fractions
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Optimized NPK fertilizer recommendations based on topsoil available nutrient criteria for wheat in drylands of China
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作者 Wenjie Yang Jie Yu +9 位作者 Yanhang Li Bingli Jia Longgang Jiang Aijing Yuan Yue Ma Ming Huang Hanbing Cao Jinshan Liu Weihong Qiu Zhaohui Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第7期2421-2433,共13页
The optimized management of crop fertilization is very important for improving crop yield and reducing the consumption of chemical fertilizers.Critical nutrient values can be used for evaluating the nutritional status... The optimized management of crop fertilization is very important for improving crop yield and reducing the consumption of chemical fertilizers.Critical nutrient values can be used for evaluating the nutritional status of a crop,and they reflect the nutrient concentrations above which the plant is sufficiently supplied for achieving the maximum potential yield.Based on on-farm surveys of 504 farmers and 60 field experimental sites in the drylands of China,we proposed a recommended fertilization method to determine nitrogen(N),phosphorus(P),and potassium(K)fertilizer input rates for wheat production,and then validated the method by a field experiment at 66 different sites in northern China.The results showed that wheat grain yield varied from 1.1 to 9.2 t ha^(-1),averaging 4.6 t ha^(-1),and it had a quadratic relationship with the topsoil(0-20 cm)nitrate N and soil available P contents at harvest.However,yield was not correlated with the inputs of N,P,and K fertilizers.Based on the relationship(exponential decay model)between 95–105%of the relative yield and topsoil nitrate N,available P,and available K contents at wheat harvest from 60 field experiments,the topsoil critical nutrient values were determined as 34.6,15.6,and 150 mg kg^(-1)for soil nitrate N,available P,and available K,respectively.Then,based on five groups of relative yield(>125%,115–125%,105–115%,95–105%,and<95%)and the model,the five groups of topsoil critical nutrient levels and fertilization coefficients(Fc)were determined.Finally,we proposed a new method for calculating the recommended fertilizer input rate as:Fr=Gy×Nr×Fc,where Fr is the recommended fertilizer(N/P/K)input rate;Gy is the potential grain yield;Nr is the N(N_(rN)),P(N_(rP)),and K(N_(rK))nutrient requirements for wheat to produce 1,000 kg of grain;and Fc is a coefficient for N(N_c)/P(P_c)/K(K_c)fertilizer.A 2-year validated experiment confirmed that the new method reduced N fertilizer input by 17.5%(38.5 kg N ha^(-1))and P fertilizer input by 43.5%(57.5 kg P_(2)O_(5) ha^(-1))in northern China and did not reduce the wheat yield.This outcome can significantly increase the farmers’benefits(by 7.58%,or 139 US$ha^(-1)).Therefore,this new recommended fertilization method can be used as a tool to guide N,P,and K fertilizer application rates for dryland wheat production. 展开更多
关键词 fertilization method dryland wheat soil nutrient critical value soil nitrogen topsoil nutrients
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Significant impacts of artificial regulation on nutrient concentrations and transport in Huanghe River
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作者 Fuxia YANG Zhigang YU +8 位作者 Alexander Felix BOUWMAN Hongtao CHEN Mengfan WU Jing LIU Dandan LI Qingzhen YAO Yao GONG Xinyu LI Wenyan GU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第6期1865-1879,共15页
Human perturbations such as dam regulation have led to significant changes in nutrient flux,structure,and spatiotemporal distribution through rivers and have greatly influenced coastal and estuarine ecological environ... Human perturbations such as dam regulation have led to significant changes in nutrient flux,structure,and spatiotemporal distribution through rivers and have greatly influenced coastal and estuarine ecological environments.Based on the data from 2001-2019,the impacts of the water-sediment regulation scheme(WSRS)in the Huanghe(Yellow)River on nutrient concentrations,forms,fluxes,and potential ecological effects on the Huanghe River estuary and Bohai Sea were analyzed.Nutrient concentrations and forms were significantly influenced by the different regulatory modes and were associated with hydrological and biogeochemical processes.The concentrations and forms of nutrients were strongly influenced by the riparian floodplains and scouring process of the downstream riverbed at the water draining stage,while they were influenced mainly by the mixing process in the Xiaolangdi Reservoir at the sediment desilting stage.Compared with those in non-WSRS years,the seasonal distributions of water discharge and nutrient fluxes in WSRS years significantly changed,with peaks occurring at least one month earlier than those in non-WSRS years.Nitrate(NO_(3)-N),phosphate(PO_4-P),and silicate(SiO_(3)-Si)fluxes during the WSRS,which were strongly controlled by water discharge at Lijin(the nearest hydrological station to the river mouth),accounted for more than 20%of the annual fluxes;these fluxes were more than 5-9 times greater than those during the same period in non-WSRS years.WSRS exacerbated nutrient imbalances and increased Pyrrophyta/Bacillariophyta ratios by 231%in the Huanghe River estuary,resulting in chlorophyll-a peaks in the Bohai Sea shifting from spring to autumn in the 20~(th)century to spring-summer in the 21^(st)century. 展开更多
关键词 water-sediment regulation scheme nutrient form nutrient flux ecological effect Huanghe(Yellow)River
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Litterfall production modeling based on climatic variables and nutrient return from stands of Eucalyptus grandis Hill ex Maiden and Pinus taeda L.
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作者 Andrés Baietto Andrés Hirigoyen +1 位作者 Jorge Hernández Amabelia del Pino 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期26-36,共11页
Native grasslands in the Pampas of South America are increasingly being replaced by Eucalyptus and Pinus stands.The short rotation regimes used for the stands require high nutrient levels,with litterfall being a major... Native grasslands in the Pampas of South America are increasingly being replaced by Eucalyptus and Pinus stands.The short rotation regimes used for the stands require high nutrient levels,with litterfall being a major source of nutrient return.To model the litterfall production using climatic variables and assess the nutrient return in 14-year-old Eucalyptus grandis and Pinus taeda stands,we measured litter production over 2 years,using conical litter traps,and monitored climatic variables.Mean temperature,accumulated precipitation,and mean maximum vapor pres-sure deficit at the seasonal level influenced litterfall produc-tion by E.grandis;seasonal accumulated precipitation and mean maximum temperature affected litterfall by P.taeda.The regression tree modeling based on these climatic vari-ables had great accuracy and predictive power for E.grandis(N=33;MAE(mean absolute error)=0.65;RMSE(root mean square error)=0.91;R^(2)=0.71)and P.taeda(N=108;MAE=1.50;RMSE=1.59;R^(2)=0.72).The nutrient return followed a similar pattern to litterfall deposition,as well as the order of importance of macronutrients(E.grandis:Ca>N>K>Mg>P;P.taeda:N>Ca>K>Mg>P)and micronutrients(E.grandis and P.taeda:Mn>Fe>Zn>Cu)in both species.This study constitutes a first approximation of factors that affect litterfall and nutrient return in these systems. 展开更多
关键词 AFFORESTATION LITTERFALL nutrient recycling Climate modeling MYRTACEAE PINACEAE
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Response of Rice Growth and Nutrient Absorption in a SalineAlkali Paddy to Different Nitrogen Fertilizer Applications
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作者 WANG Xinyi ZHU Hui +2 位作者 YAN Baixing Brian SHUTES ZENG Yuan 《Rice science》 SCIE CSCD 2024年第3期245-250,I0011-I0017,共13页
Nitrogen(N),phosphorus(P)and carbon(C)are essential nutrients for rice growth and development,but the response of nutrient absorption by rice plants to different types of nitrogen fertilizer(N-fertilizer)under saline-... Nitrogen(N),phosphorus(P)and carbon(C)are essential nutrients for rice growth and development,but the response of nutrient absorption by rice plants to different types of nitrogen fertilizer(N-fertilizer)under saline-alkali conditions is unclear.This study conducted a 147-day field-scale experiment to evaluate rice biomass and nutrient absorption capacity with five N-fertilizer applications.The results showed that the biomass. 展开更多
关键词 nutrient ALKALI ALKALI
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Development and Validation of Integrated Nutrient Management Practices of Industrial Processing Varieties: Asterix and Courage in Bangladesh
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作者 Azizul Hoque Md. Maniruzzaman Sikder Abul Khair 《Agricultural Sciences》 2024年第7期780-799,共20页
An experiment was meticulously conducted at the research field of Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Gazipur, Bangladesh, during the 2011-2012 potato growing season to develop integrat... An experiment was meticulously conducted at the research field of Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Gazipur, Bangladesh, during the 2011-2012 potato growing season to develop integrated crop management practices for the potato seed production of industrial processing varieties Asterix and Courage. Significantly, higher growth and yield parameters were found in the BADC-recommended practice. Later, another experiment was conducted to validate the BADC practice during the 2013-2014 potato growing season in two locations in Bangladesh. Results showed that the production of tuber per hill, tuber weight per hill as well as gross tuber yield per plot, higher proportion of storable seed tubers, and more quality seed potatoes (A-grade and B-grade) seed tubers were found significantly higher in the “BADC developed practice” compared to other treatments. Viral diseases (PLRV and PVY) prevalence was lower in “BADC developed practice”. Moreover, “BADC developed practice” contributed more economic yield by minimizing input cost compared to “Munshiganj advanced farmers’ practice”. Therefore, the “BADC developed practice” was found “superior” regarding yield, quality, and profitability in seed potato production of industrial varieties—Asterix and Courage in Bangladesh. 展开更多
关键词 Integrated nutrient Industrial Processing POTATOES
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Occurrence,Spatial Distribution,Sources and Risk Assessment of Per-and Polyfluoroalkyl Substances in Surface Sediments of the Yellow River Delta Wetland
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作者 SUN Yu SHEN Nan +5 位作者 ZHANG Dahai CHEN Junhui HE Xiuping JI Yinli WANG Haiyang LI Xianguo 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第5期1263-1274,共12页
Per-and polyfluoroalkyl substances(PFASs)are emerging persistent organic pollutants(POPs).In this study,47 surface sediment samples were collected from the Yellow River Delta wetland(YRDW)to investigate the occurrence... Per-and polyfluoroalkyl substances(PFASs)are emerging persistent organic pollutants(POPs).In this study,47 surface sediment samples were collected from the Yellow River Delta wetland(YRDW)to investigate the occurrence,spatial distribution,potential sources,and ecological risks of PFASs.Twenty-three out of 26 targeted PFASs were detected in surface sediment samples from the YRDW,with totalΣ23PFASs concentrations ranging from 0.23 to 16.30 ng g^(-1) dw and a median value of 2.27 ng g^(-1) dw.Perfluorooctanoic acid(PFOA),perfluorobutanoic acid(PFBA)and perfluorooctanesulfonic acid(PFOS)were the main contaminants.The detection frequency and concentration of perfluoroalkyl carboxylic acids(PFCAs)were higher than those of perfluoroal-kanesulfonic acids(PFSAs),while those of long-chain PFASs were higher than those of short-chain PFASs.The emerging PFASs substitutes were dominated by 6:2 chlorinated polyfluoroalkyl ether sulfonic acid(6:2 Cl-PFESA).The distribution of PFASs is significantly influenced by the total organic carbon content in the sediments.The concentration of PFASs seems to be related to human activities,with high concentration levels of PFASs near locations such as beaches and villages.By using a positive matrix factorization model,the potential sources of PFASs in the region were identified as metal plating mist inhibitor and fluoropolymer manufacturing sources,metal plating industry and firefighting foam and textile treatment sources,and food packaging material sources.The risk assessment indicated that PFASs in YRDW sediments do not pose a significant ecological risk to benthic organisms in the region overall,but PFOA and PFOS exert a low to moderate risk at individual stations. 展开更多
关键词 per-and polyfluoroalkyl substances Yellow River Delta wetland sediment source identification risk assessment
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Correlation of gut microorganisms and non-volatile flavor substances provides new insights for breeding Scylla paramamosain
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作者 Gao GAO Xing LI +7 位作者 Kangxiang QIN Yun HU Xiaosong JIANG Chenxi CHE Yuntao LI Changkao MU Chunlin WANG Huan WANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1336-1347,共12页
The farming of Scylla paramamosain with specific flavors has a higher commercial value,and the flavors are related to the integrated farming environment and non-volatile flavor substances,while the survival environmen... The farming of Scylla paramamosain with specific flavors has a higher commercial value,and the flavors are related to the integrated farming environment and non-volatile flavor substances,while the survival environment is one of the important ways to source gut microorganisms in the organism.In this study,the levels of dominant taxa in the gut flora of S.paramamosain from Mong Cai,Vietnam(VN),Taishan City,Guangdong Province(TS)of China,and Ninghai County,Ningbo City(NB)Zhejiang Province of China converged with those of S.paramamosain from Sanmen County,Ningbo City(CK 1,CK 2,and CK 3)at 28 d of domestication.The top 15 genera with the highest abundance of VN,TS,and NB gut flora were the same as CK 1,CK 2,and CK 3,but with different percentages,and gradually converged to CK 1,CK 2,and CK 3,respectively,at 28 d of domestication.Correlation between intestinal flora and non-volatile flavor substances in the hepatopancreas at the percentage level of relative abundance of bacterial genera found that above 28 d of domestication,Muribaculaceae,Psychrilyobacter,Clostridia_vadinBB 60_group,Halarcobacter Carboxylicivirga,Sediminispirochaeta may be the most important genera affecting flavor amino acids of VN.Sediminispirochaeta,Carboxylicivirga,Halarcobacter,Photobacterium,ZOR 0006,Psychrilyobacter,and Pseudomonas may be the most important genera affecting flavor amino acids of NB.Sediminispirochaeta,Carboxylicivirga,Halarcobacter,Photobacterium,ZOR 0006,Vibrio,and Sphingomonas may be the most important genera affecting flavor amino acids of TS.These results show that the intestinal flora structure of crabs from different areas were domesticated in the same area for at least 28 d before they converged to that of the domesticated crab,and the most important genera affecting the flavor amino acids of TS,VN,and NB were also identified.The results of this study provide a reference and basis for the technique of directional cultivation of the flavor quality of the crab. 展开更多
关键词 survival environment Scylla paramamosain intestinal flora structure non-volatile flavor substance directional breeding
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