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A comprehensive review about sperm-oocyte interactions and key activation factors of fertilization in mammals
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作者 Soukaina Azil Yassmine Louanjli +2 位作者 Noureddine Louanjli Moncef Benkhalifa Bouchra Ghazi 《The Canadian Journal of Urology》 2026年第1期51-62,共12页
Mammalian fertilization involves the migration of spermatozoa through the female reproductive system.Early embryonic development is a consequence of several steps and signaling pathways being activated,as well as bioc... Mammalian fertilization involves the migration of spermatozoa through the female reproductive system.Early embryonic development is a consequence of several steps and signaling pathways being activated,as well as biochemical and morphological modifications of spermatozoa that enable them to penetrate the membrane of mature oocytes.There are some crucial steps known to clearly explain the process of fertilization,starting with hyperactivation of spermatozoa,mutual recognition,and binding of gametes mediated by receptors located on the surface membranes of both gametes.The final step is followed by oocyte activation,which is primarily triggered via sperm-derived factors,inducing a sharp increase in intracellular calcium levels,eventually leading to polyspermy block.This review integrates current knowledge of the molecular and physiological events governing fertilization,emphasizing how ion regulation and signaling pathways converge to enable sperm function and oocyte activation.Special attention is given to sperm-derived factors such as phospholipase C zeta(PLCζ)and post-acrosomal sheath WW domain-binding protein(PAWP),which play essential roles in triggering calcium release and supporting early embryonic development. 展开更多
关键词 male infertility fertilization association sperm-oocyte oocyte activation phospholipase C zeta
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Successful rescue activation of unfertilized oocytes with calcium ionophore(A23187)in a case of recurrent ICSI fertilization failure:A case report
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作者 Akash More Vilas Chimurkar +2 位作者 Namrata Choudhary Dipali More Sanket Mahajan 《Asian pacific Journal of Reproduction》 2026年第1期45-48,共4页
Rationale:This case report describes a couple with recurrent fertilization failure despite undergoing multiple cycles of intracytoplasmic sperm injection(ICSI).The principal clinical concern was suspected oocyte activ... Rationale:This case report describes a couple with recurrent fertilization failure despite undergoing multiple cycles of intracytoplasmic sperm injection(ICSI).The principal clinical concern was suspected oocyte activation deficiency(OAD),in which fertilization is impeded due to the oocyte’s inability to initiate embryogenesis,commonly attributed to inadequate intracellular calcium(Ca^(2+))release following sperm injection.Patient concerns:The couple repeatedly experienced complete or near-complete fertilization failure in previous ICSI cycles,raising suspicion of an underlying oocyte activation defect.Diagnosis:Based on the repeated absence of fertilization post-ICSI and clinical history,a diagnosis of suspected OAD leading to recurrent ICSI fertilization failure was considered.Interventions:Artificial oocyte activation(AOA)using the calcium ionophore A23187 was performed.After ICSI,unfertilized oocytes were exposed to the ionophore to induce Ca^(2+)influx,simulating physiological calcium oscillations essential for oocyte activation.The efficacy of intervention was evaluated through subsequent embryonic development,morphological grading,and chromosomal integrity.Outcomes:Following AOA treatment,successful oocyte activation occurred,resulting in the formation of high-grade embryos with normal developmental progression.Chromosomal analysis revealed no detectable abnormalities,indicating genomic stability.Lessons:Calcium ionophore–mediated AOA may serve as an effective adjunct in cases of recurrent ICSI failure attributed to OAD.This case highlights the importance of individualized therapeutic strategies in assisted reproduction;however,further research is needed to refine protocols,validate broader clinical efficacy,and assess long-term safety,including potential epigenetic risks. 展开更多
关键词 Oocyte activation deficiency Intracytoplasmic sperm injection Artificial oocyte activation Calcium ionophore A23187 fertilization failure Assisted reproductive technology
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Impacts of Fertilization and Soil Amendments on Rhizosphere Microbiota and Growth of Panax:A Meta-Analysis
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作者 Hong Chen Runze Yang +4 位作者 Jing Tian Boyuan Xu Qiang Chen Yuzong Chen Ming-Xiao Zhao 《Phyton-International Journal of Experimental Botany》 2026年第1期187-202,共16页
Panax species are globally recognized for their high medicinal and economic value,yet large-scale cultivation is constrained by high production costs,progressive soil acidification,and persistent soil-borne diseases.A... Panax species are globally recognized for their high medicinal and economic value,yet large-scale cultivation is constrained by high production costs,progressive soil acidification,and persistent soil-borne diseases.Although various soil improvement strategies have been tested,a comprehensive synthesis of their comparative effectiveness has been lacking.Here,we conducted a meta-analysis of 1381 observations from 54 independent studies to evaluate the effects of conventional fertilizers,microbial fertilizers,organic amendments,and inorganic amendments on Panax cultivation.Our results demonstrate that microbial fertilizers,organic amendments,and inorganic amendments significantly increased soil pH,thereby ameliorating soil acidification.Among them,organic amendments significantly enhanced the content of soil organic carbon,available nitrogen,and available phosphorus,alongside a notable increase in microbial diversity(Chao1 and ACE indices,which increased by 9%and 17%,respectively).Moreover,our analysis revealed that while microbial fertilizers,organic amendments,and inorganic amendments(except conventional fertilizers)reduced the disease index of Panax plants,organic amendments demonstrated absolute superiority in promoting plant height,root dry weight,root fresh weight,and root length.By quantitatively integrating multi-source evidence,this study provides novel mechanistic insights and practical recommendations that extend beyond local practices,offering guidance for sustainable ginseng cultivation and broader medicinal plant production systems worldwide. 展开更多
关键词 Panax cultivation soil amendments fertilizers soil bacteria
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Effects of NPK and Micronutrient Fertilization on Soil Enzyme Activities,Microbial Biomass,and Nutrient Availability
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作者 Dilfuza Jabborova Khurshid Sulaymanov +5 位作者 Muzafar Jabborov Nayan Ahmed Tatiana Minkina Olga Biryukova Nasir Mehmood Vishnu D.Rajput 《Phyton-International Journal of Experimental Botany》 2026年第1期119-131,共13页
The combined effects of macronutrients(Nitrogen,Phosphorus,and Potassium-N,P,K)and micronutrient fertilization on turmeric yield,soil enzymatic activity,microbial biomass,and nutrient dynamics remains poorly understoo... The combined effects of macronutrients(Nitrogen,Phosphorus,and Potassium-N,P,K)and micronutrient fertilization on turmeric yield,soil enzymatic activity,microbial biomass,and nutrient dynamics remains poorly understood,despite their significance for sustainable soil fertility management and optimizing crop productivity across diverse agroecosystems.To investigate,a net house experiment on sandy loam Haplic Chernozem was conducted to 03 fertilizer regimes,viz.N_(75)P_(50)K_(50)kg ha^(−1)(T-2),N_(12)5P_(100)K_(100)kg ha^(−1)(T-3),and N_(100)P_(75)K_(75)+B_(3)Zn_(6)Fe_(6)kg ha^(−1)(T-4).Furthermore,the influence of these treatments was systematically assessed on soil nutrient status(N,P,K),enzymatic activities(alkaline phosphomonoesterase,dehydrogenase,fluorescein diacetate hydrolysis),microbial biomass carbon(MBC)and soil organic carbon(SOC).Balanced fertilization significantly turmeric productivity and soil health.All three fertilizer treatments showed a clear yield increase compared to the unfertilized control.Compared to the control,N_(75)P_(50)K_(50)kg/ha T-2 increased rhizome number and biomass per plant by 44.7%and 16.3%,respectively,while N_(100)P_(75)K_(75)+B_(3)Zn_(6)Fe_(6)kg/ha T-4 further enhanced them by 86.6%and 27.7%.T-3 produced the most significant yield response by increasing the rhizome biomass by 38.0%and rhizome number per plant by 100%compared to the control.The nutrient availability was also substantially improved.T-2 enhanced the soil nitrogen contents by 83.3%with maximum N levels observed in T-3&T-4.Phosphorus increased by 61.5%in T-3 and 37.3%in T-4,while potassium was enhanced by 12.9%in T-3 relative to the control,respectively.Enzymatic activities were markedly enhanced as T-3 was recorded to improve alkaline phosphomonoesterase(APA),dehydrogenase(DHA)and fluorescein diacetate hydrolysis(FDA)by 50.6%,37.4%,and 43.4%,where T-4 increased by 32.2%,30.9%,and 35.9%,respectively compared to control.MBC and SOC also rose significantly,with SOC increased by 13.8%(T-2),41.6%(T-3),and 47.2%(T-3)relative to control.The result of this study demonstrates that the integrated macro&micronutrient fertilization,particularly T-37 T-4 treatments,sustainably enhanced turmeric yield,soil nutrient availability,enzyme activity,microbial biomass,and organic carbon.These findings highlight the critical role of balanced nutrient management in sustaining soil fertility and crop productivity across agroecosystems. 展开更多
关键词 NPK fertilizer micronutrients(Boron Zinc Iron) soil enzyme activity microbial bio-mass carbon soil organic carbon turmeric
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Post-silking leaf senescence is delayed in low-N-tolerant maize cultivars under low N fertilization 被引量:2
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作者 Gui Wei Xinglong Wang +6 位作者 Yawei Wu Fan Liu Tianqiong Lan Qinlin Liu Chengcheng Lyu Fanlei Kong Jichao Yuan 《The Crop Journal》 2025年第1期246-256,共11页
A four-year field experiment was conducted with two cultivars and four N rate to investigate the spatiotemporal characteristics of leaf senescence in maize after silking and its response to N fertilizer rates on them,... A four-year field experiment was conducted with two cultivars and four N rate to investigate the spatiotemporal characteristics of leaf senescence in maize after silking and its response to N fertilizer rates on them,as well as to reveal the differences in post-silking chlorophyll degradation between low-N-tolerant cultivars.The results showed that the order of leaf senescence after silking in maize was lower leaf>upper leaf>ear leaf,leaf tip>middle>base.Increasing N fertilizer down-regulated the expression of ZmCLH2 and ZmPPH in the leaves at 10-30 d after silking,reducing CLH and PPH activities,thereby delaying the leaf senescence.These effects were more prominent in low-N-sensitive cultivar Xianyu 508(XY508)than in low-N-tolerant cultivar Zhenghong 311(ZH311),especially in the lower leaves and leaf tip.Under low N condition,leaf yellowing and chlorophyll degradation occurred later and slower in ZH311 than in XY508.This resulted in a higher post-silking dry matter accumulation and grain yield in ZH311,which may be one of the important physiological bases of low nitrogen tolerant cultivars.Future research should focus on developing low-N-tolerant maize cultivars with slower leaf senescence near the ear after silking. 展开更多
关键词 Low-N-tolerant maize variety Nitrogen fertilizer Spatio-temporal characteristics Chlorophyll degradation
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Exploring the spatiotemporal heterogeneity of vegetation changes in subtropical humid karst region under CO_(2)fertilization 被引量:1
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作者 CHEN Meng ZHOU Qiuwen +1 位作者 PENG Dawei YAN Weihong 《Journal of Geographical Sciences》 2025年第1期65-87,共23页
Terrestrial ecosystems heavily depend on vegetation,which responds to carbon dioxide(CO_(2))fertilization in hot and humid regions.The subtropical humid karst region is a hot and humid region;whether and to what exten... Terrestrial ecosystems heavily depend on vegetation,which responds to carbon dioxide(CO_(2))fertilization in hot and humid regions.The subtropical humid karst region is a hot and humid region;whether and to what extent CO_(2)fertilization affects vegetation changes in such regions remains unclear.In this study,we investigated the degree to which CO_(2)fertilization influences vegetation changes,along with their spatial and temporal differences,in the subtropical humid karst region using time-lag effect analysis,a random forest model,and multiple regression analysis.Results showed that CO_(2)fertilization plays an important role in vegetation changes,exhibiting clear spatial variations across different geomorphological zones,with its degree of influence ranging mainly between 11%and 25%.The highest contribution of CO_(2)fertilization was observed in the karst basin and non-karstic region,whereas the lowest contribution was found in the karst plateau region.Previous studies have primarily attributed vegetation changes in subtropical humid karst region to ecological engineering,leading to an overestimation of its contribution to these changes.The findings of this study enhance the understanding of the mechanism of vegetation changes in humid karst region and provide theoretical and practical insights for ecological and environmental protection in these regions. 展开更多
关键词 KARST vegetation changes NDVI driving factors carbon dioxide fertilization
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Optimizing tillage and fertilization practices to improve the carbon footprint and energy efficiency of wheat-maize cropping systems 被引量:1
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作者 Kun Han Xinzhu Li +5 位作者 Liang Jia Dazhao Yu Wenhua Xu Hongkun Chen Tao Song Peng Liu 《Journal of Integrative Agriculture》 2025年第10期3789-3802,共14页
To make agricultural systems sustainable in terms of their greenness and efficiency,optimizing the tillage and fertilization practices is essential.To assess the effects of tilling and fertilization practices in wheat... To make agricultural systems sustainable in terms of their greenness and efficiency,optimizing the tillage and fertilization practices is essential.To assess the effects of tilling and fertilization practices in wheat-maize cropping systems,a three-year field experiment was designed to quantify the carbon footprint(CF)and energy efficiency of the cropping systems in the North China Plain.The study parameters included four tillage practices(no tillage(NT),conventional tillage(CT),rotary tillage(RT),and subsoiling rotary tillage(SRT))and two fertilizer regimes(inorganic fertilizer(IF)and hybrid fertilizer with organic and inorganic components(HF)).The results indicated that the most prominent energy inputs and greenhouse gas(GHG)emissions could be ascribed to the use of fertilizers and fuel consumption.Under the same fertilization regime,ranking the tillage patterns with respect to the value of the crop yield,profit,CF,energy use efficiency(EUE)or energy productivity(EP)for either wheat or maize always gave the same sequence of SRT>RT>CT>NT.For the same tillage,the energy consumption associated with HF was higher than IF,but its GHG emissions and CF were lower while the yield and profit were higher.In terms of overall performance,tilling is more beneficial than NT,and reduced tillage practices(RT and SRT)are more beneficial than CT.The fertilization regime with the best overall performance was HF.Combining SRT with HF has significant potential for reducing CF and increasing EUE,thereby improving sustainability.Adopting measures that promote these optimizations can help to overcome the challenges posed by a lack of food security,energy crises and ecological stress. 展开更多
关键词 reduced tillage organic fertilizer greenhouse gases C footprint energy use efficiency
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Influence of Outdoor Light at Night on Early Reproductive Outcomes of In Vitro Fertilization and Its Threshold Effect:Evidence from a Couple-Based Preconception Cohort Study
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作者 Wenbin Fang Ying Tang +12 位作者 Yaning Sun Yanlan Tang Yinyin Chen Yawen Cao Jiqi Fang Kunjing He Yushan Li Yaning Dai Shuangshuang Bao Peng Zhu Shanshan Shao Fangbiao Tao Guixia Pan 《Biomedical and Environmental Sciences》 2025年第8期1009-1015,共7页
Infertility,defined as the inability to achieve a clinical pregnancy after 1 year of unprotected and regular sexual intercourse,affects approximately 8%–12%of couples worldwide during their childbearing years.Assiste... Infertility,defined as the inability to achieve a clinical pregnancy after 1 year of unprotected and regular sexual intercourse,affects approximately 8%–12%of couples worldwide during their childbearing years.Assisted reproductive technology(ART)offers interventions to facilitate conception in couples with infertility.Since the inception of traditional in vitro fertilization(IVF)in 1978,ART has facilitated the birth of millions of infants.Intracytoplasmic sperm injection(ICSI)is an effective technique for couples ineligible for traditional IVF.Individual female factors,such as age and endometrial thickness,have been shown to affect embryo development during the IVF process,resulting in unfavorable pregnancy outcomes[1-3].However,the influence of environmental and male factors on early reproductive outcomes cannot be ignored.As a novel form of environmental pollution,light at night(LAN)has intensified with the rapid pace of urbanization,potentially leading to reproductive health problems in both women and men.However,to our knowledge,no study has explored the effects of LAN exposure on the early reproductive outcomes of IVF.Furthermore,the normal development of embryos relies on the contributions of both partners,and the influence of male factors on the early reproductive outcomes of IVF should not be overlooked. 展开更多
关键词 Preconception cohort study reproductive technology art offers vitro fertilization traditional vitro fertilization ivf Outdoor light night Early reproductive outcomes Threshold effect sperm injection icsi
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Five-year controlled-release/stable nitrogen fertilization reduces field nitrogen loss without increasing carbon dioxide emissions in a vegetable rotation system
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作者 Fangli WANG Zhi LI +7 位作者 Dan ZHENG Shangqiang LIAO Xi ZHANG Zihan YU Jun LIU Haiying ZONG Xuexia WANG Ningning SONG 《Pedosphere》 2025年第4期741-750,共10页
Controlled-release/stable nitrogen(N)fertilizers can improve vegetable yields and achieve lower greenhouse gas emissions,resulting in cost-effective and environmentally friendly vegetable production.However,there has ... Controlled-release/stable nitrogen(N)fertilizers can improve vegetable yields and achieve lower greenhouse gas emissions,resulting in cost-effective and environmentally friendly vegetable production.However,there has been limited research on the controlled-release/stable N fertilization in long-term fixed-position vegetable rotation fields.In this study,a five-year field experiment was conducted to examine the effects of long-term controlled-release/stable N fertilization in reducing greenhouse gas emissions and increasing lettuce yield.Six distinct treatments were employed for N fertilization:the control without N fertilizer(CK),normal local farming practices with application of urea fertilizer at 400 kg N ha^(-1)(T1),optimized application of urea at 320 kg N ha^(-1)(T2),optimized application of urea at 320 kg N ha^(-1)with supplementation of 1.0 kg ha^(-1)3,4-dimethylpyrazole phosphate(DMPP)as N inhibitor(T3),application of polyurethane-coated urea at 320 kg N ha^(-1)(T4),and application of polyurethane-coated urea at 320 kg N ha^(-1)with supplementation of 1.0 kg ha^(-1)DMPP(T5).The results showed that the T3,T4,and T5 treatments using controlled-release/stable N fertilization emitted about 12.2%-56.7%less average annual cumulative nitrous oxide(N_(2)O)and 1.31%-10.0%less carbon dioxide(CO_(2))than the T2 treatment.Nitrous oxide and CO_(2)emissions from the T4 and T5 treatments were considerably lower than those from the T3 treatment.No significant seasonal or interannual variability was observed in N_(2)O and CO_(2)emissions.The observed phenomena were attributed to the fluctuations in soil ammonium-and nitrate-N contents.The findings in this study revealed that long-term controlled-release/stable N fertilization resulted in reduced field N loss,benefitting vegetable yields without increasing CO_(2)emissions and highlighting the application potential of this technique for sustainable agricultural production. 展开更多
关键词 controlled-release N fertilizer greenhouse gas emissions nitrification inhibitor stable N fertilizer vegetable yield
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Design and experiment of the variable rate fertilization system for soybeanand maize strip compound planting
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作者 Li Ding Kaixuan Wang +6 位作者 Yechao Yuan Yuanyuan Li Huanhuan Chen Zheng Zhang Qianyi Wang Changchang Yu He Li 《International Journal of Agricultural and Biological Engineering》 2025年第6期122-134,共13页
In view of the existing composite planting cannot do independent control of fertilizer rate for each row,and fertilizer is easy to moisture solidification caking and rely on a single way to measure the speed of inaccu... In view of the existing composite planting cannot do independent control of fertilizer rate for each row,and fertilizer is easy to moisture solidification caking and rely on a single way to measure the speed of inaccurate problems,a split-drive variable fertilizer application system was designed for soybean and maize strip cropping composites.It includes roller crushing bi-directional spiral fertilizer discharger,split-drive variable fertilizer application system and‘GNSS+encoder’dual speed measurement system.By modeling agglomerated fertilizer particles,discrete element simulation was carried out to analyze the crushing effect.The speed measurement error variation folds of both GNSS and encoder under different speed conditions were obtained through field speed measurement tests.Finally,4.5 km/h was identified as the switching point between the two speed measurements.Through bench testing,a mathematical relationship model was developed for the soybean and maize belts in terms of‘Fertilizer Application Rate-Operating Travel Speed-Metering Mechanism Rotor Speed’,and the results are presented in the table below.Fertilizer discharge consistency was verified for fertilizer dischargers.Field trials were conducted,and the results show:The soybean belt had a maximum error of 4.81%at a fertilizer application rate of 150 kg/hm2 and an operating speed of 5 km/h;the maximum error in the corn belt was 4.67%at a fertilizer application rate of 600 kg/hm2 and operating speed of 4 km/h.Both have a maximum error of less than 5%,which meets the requirements for variable fertilizer application. 展开更多
关键词 variable fertilization EDEM simulation soybean corn compound planting spiral fertilizer apparatus
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Diagnosis and treatment strategy of acupuncture-moxibustion for advanced-age infertility in vitro fertilization and embryo transfer based on the temporal rhythm theory of traditional Chinese medicine
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作者 Shu Bee CHEN Jing LIU +4 位作者 Xue-si HOU Li-kun YANG Yi-ni SUN Shu-qi MI Ji-ping ZHAO 《World Journal of Acupuncture-Moxibustion》 2025年第2期113-118,共6页
The ability of natural conception decreases with age,leading many advanced-age women with fertility desire begin to attempt in vitro fertilization and embryo transfer(IVF-ET)technique nowadays.Traditional Chinese medi... The ability of natural conception decreases with age,leading many advanced-age women with fertility desire begin to attempt in vitro fertilization and embryo transfer(IVF-ET)technique nowadays.Traditional Chinese medicine(TCM)believes that human body undergoes periodic changes corresponding to the natural rhythms.Women exhibit distinct physiological lunar rhythms of the thoroughfare vessel and the conception vessel,as well as pathological rhythms during the menstrual cycle and IVF-ET cycle.Based on the theory of TCM temporal rhythm,this paper discusses the pathogenesis characteristics of infertility in advanced-age women at different stages.It believes that acupuncture intervention should comply with the following ideas:determining main acupoints based on disease differentiation,with a preference for the acupoints on the thoroughfare vessel,the conception vessel,spleen meridian and kidney meridian,as well as the back-shu points of the liver,spleen and kidney;determining the supplementary acupoints based on syndrome differentiation and symptoms;determining the supplementary acupoints based on time differentiation of lunar rhythm of the thoroughfare vessel and the conception vessel,and integrating both reinforcing and reducing techniques.During the process of intervention,the physical and mental states were balanced simultaneously. 展开更多
关键词 ACUPUNCTURE-MOXIBUSTION INFERTILITY Temporal rhythm In vitro fertilization and embryo transfer Advanced age
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Optimized boll-loading capacity of cotton root system increases seedcotton yield under wheat-cotton straw return with appropriate nitrogen fertilization
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作者 Zhitao Liu Wen Jin +5 位作者 Qin Wang Wei Hu Binglin Chen Yali Meng Haishui Yang Zhiguo Zhou 《The Crop Journal》 2025年第2期576-586,共11页
Long-term straw return with appropriate nitrogen(N)fertilization increases seedcotton yield and fiber quality,and the root system plays an important role in cotton production.However,under straw return and N fertiliza... Long-term straw return with appropriate nitrogen(N)fertilization increases seedcotton yield and fiber quality,and the root system plays an important role in cotton production.However,under straw return and N fertilization,the relationship between the cotton boll-loading capacity of the root system and seedcotton yield remains unclear.In this study,a ten years of long-term field experiment was conducted in a wheat-cotton rotation system.The effects of straw treatments(straw return and straw removal)and N rates(N0,N75,N150 and N300 representing 0,75,150 and 300 kg N ha^(-1),respectively)on cotton root activity,boll-loading capacity of the root system and their relationship to seedcotton yield from 2019 to 2022 were quantified.The results showed that straw return with an appropriate N fertilization of N150 increased root biomass,the rate and components of root-bleeding sap,as well as boll-loading capacity of the root system and seedcotton yield,but decreased the ratio of root to shoot biomass.Furthermore,the root-bleeding sap rate reached the maximum at 30 d post anthesis(DPA)during the peak boll setting stage.However,the contents of nitrate-N,free amino acids and soluble sugar in root-bleeding sap decreased from 10 DPA.Notably,in 2021 and at 30 DPA,the highest contents of nitrate-N(4.8μg mL^(-1))and free amino acids(8.3μg mL^(-1)),as well as soluble sugar(3.4μg mL^(-1))were observed at N150 under straw return.The increase in seedcotton yield is positively correlated to the soluble sugar content.Straw return significantly increased the boll-loading capacity of the root system,which first increased but then decreased with the increase in N fertilization.Under straw return with N150,the maximum seecotton yield(3455-4544 kg ha^(-1))was recorded,and the largest boll loading(49-54 boll 100 g^(-1))and boll capacity(242-292 g 100 g^(-1))of root system at the boll opening stage were observed.Therefore,straw return with appropriate N fertilization improved root activity and the boll-loading capacity of the root system,thereby increasing seedcotton yield.This study provides new insights into improving seedcotton yield from the perspective of coordinating cotton growth. 展开更多
关键词 Wheat-cotton straw return Nitrogen fertilization Seedcotton yield Root-bleeding sap Boll-loading capacity of the root system
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Comparing carbon sequestration efficiency in chemically separated soil organic carbon fractions under long-term fertilization in three major Chinese croplands
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作者 Hu Xu Adnan Mustafa +5 位作者 Lu Zhang Shaomin Huang Hongjun Gao Mohammad Tahsin Karimi Nezhad Nan Sun Minggang Xu 《Journal of Integrative Agriculture》 2025年第7期2841-2856,共16页
The combined application of organic manure and chemical fertilizers is an effective way to enhance soil organic carbon(SOC)sequestration through its influences on organic carbon(OC)input and the stability of SOC fract... The combined application of organic manure and chemical fertilizers is an effective way to enhance soil organic carbon(SOC)sequestration through its influences on organic carbon(OC)input and the stability of SOC fractions.However,there is limited information on the carbon sequestration efficiency(CSE)of chemically separated SOC fractions and its response to OC input under long-term fertilization regimes,especially at different sites.This study used three long-term fertilization experiments in Gongzhuling,Zhengzhou and Qiyang spanning 20 years to compare the stocks and CSE in four different OC fractions(very labile OC,labile OC,less labile OC,and non-labile OC)and their relationships with annual OC input.Three treatments of no fertilization(CK),chemical nitrogen,phosphorous,and potassium fertilizers(NPK),and chemical NPK combined with manure(NPKM)were employed.The results showed that compared with CK,NPKM resulted in enhanced SOC stocks and sequestration rates as well as CSE levels of all fractions irrespective of experimental site.Specifically for the very labile and non-labile OC fractions,NPKM significantly increased the SOC stocks by 43 and 83%,77 and 86%,and 73 and 82%in Gongzhuling,Qiyang,and Zhengzhou relative to CK,respectively.However,the greatest changes in SOC stock relative to the initial value were associated with non-labile OC fractions in Gongzhuling,Zhengzhou,and Qiyang,which reached 6.65,7.16,and 7.35 Mg ha^(-1) under NPKM.Similarly,the highest CSE was noted for non-labile OC fractions under NPKM followed sequentially by the very labile OC,labile OC,and less-labile OC fractions,however a CSE of 8.56%in the non-labile OC fraction for Gongzhuling was higher than the values of 6.10 and 4.61%in Zhengzhou and Qiyang,respectively.In addition,the CSE for the passive pool(very labile+labile OC fractions)was higher than the active pool(less-labile+non-labile OC fractions),with the highest value in Gongzhuling.The redundancy analysis revealed that the CSEs of fractions and pools were negatively influenced by annual OC input,mean annual precipitation and temperature,but positively influenced by the initial SOC and total nitrogen contents.This suggests that differential stability of sequestered OC is further governed by indigenous site characteristics and variable amounts of annual OC input. 展开更多
关键词 long-term field experiment fertilization carbon sequestration efficiency organic carbon stability organic carbon fractionation
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Changes in cropland soil inorganic carbon and its relationship with nitrogen fertilization and precipitation over the past 40 years in the Sichuan Basin,China
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作者 Aiwen Li Jinli Cheng +10 位作者 Dan Chen Xinyi Chen Yaruo Mao Qian Deng Bin Zhao Wenjiao Shi Zemeng Fan John PWilson Tianfei Dai Tianxiang Yue Qiquan Li 《Journal of Integrative Agriculture》 2025年第11期4415-4429,共15页
Widespread soil acidification driven by nitrogen(N)fertilization and precipitation challenges the conventional notion of the long-term stability of soil inorganic carbon(SIC)in agroecosystems.However,the changes in SI... Widespread soil acidification driven by nitrogen(N)fertilization and precipitation challenges the conventional notion of the long-term stability of soil inorganic carbon(SIC)in agroecosystems.However,the changes in SIC with precipitation and N fertilization remain ambiguous.Based on 4,000+soil samples collected in the 1980s and 2010s and by developing machine learning models to fill the missing SIC of soil samples,this study generated 3,697 paired soil samples between the two periods and then investigated the cropland SIC change and explored its relationship with precipitation and N fertilization across the Sichuan Basin,China.The results showed an overall SIC loss,with a decline of the mean SIC by 15.73%.SIC change varied with initial soil pH and initial SIC and exhibited an exponential relationship with soil pH change,indicating the changing role of carbonates in providing acid-buffering capacity.There was a parabolical relationship between the magnitude of SIC decline and N fertilizer rates,and low N fertilizer rates contributed to a reduction in SIC loss,while SIC loss was promoted by N fertilization occurred when N fertilizing rates exceeded 250 kg ha^(-1) yr^(-1).The change in SIC showed a sinusoidal variation with precipitation,with 950 mm being the threshold controlling whether SIC increased or decreased.Meanwhile,N fertilization did not alter the sinusoidal relationship between SIC change and precipitation.In areas with rainfall<950 mm,the high N fertilizer rate did not cause SIC loss,while higher precipitation could also cause larger SIC loss in areas with lower N fertilizer rates.These results suggest that SIC dynamics are jointly driven by precipitation and N fertilization and are controlled by acid-buffering mechanisms associated with initial pH and SIC,with precipitation being the predominant driver.These findings emphasize the need for more regional soil observations and in-depth studies of SIC change and its mechanisms for accurately estimating SIC change. 展开更多
关键词 soil inorganic carbon change nitrogen fertilization PRECIPITATION Sichuan Basin
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Response of Saline-alkali Cropland Soil CO_(2)Fluxes to Nitrogen Fertilization,Irrigation and Temperature via DAYCENT Modeling
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作者 Peng ZHANG Hanxiao FENG +2 位作者 Liming LAI Haiwei WANG Yang YANG 《Agricultural Biotechnology》 2025年第3期56-63,共8页
A growing global demand exists to formulate plans to lessen the greenhouse gas emissions produced by agricultural activities.The purpose of this study was to uncovered the changes in soil CO_(2)fluxes under varying sc... A growing global demand exists to formulate plans to lessen the greenhouse gas emissions produced by agricultural activities.The purpose of this study was to uncovered the changes in soil CO_(2)fluxes under varying scenarios including nitrogen fertilization rates,irrigation rates,and air temperatures in the Hetao Irrigation District(HID)over the 38-year period.DAYCENT model was used to predict carbon dioxide(CO_(2))fluxes from cultivated soils in the HID,Inner Mongolia from^(2)023 to 2060(the year of achieving the"carbon neutrality"goal)in this study.Results showed that mean soil CO_(2)fluxes in the sunflower field[1035.13 g/(m^(2).yr)]were significantly lower than those in the maize field[1405.54 g/(m^(2).yr)].An increase in nitrogen fertilization rate led to a significant escalation in soil CO_(2)fluxes.Moreover,elevating irrigation rates for washing salts by irrigation(WSBI)diminished soil CO_(2)fluxes in the sunflower field while amplifying them in the maize field.A rise in air temperature resulted in an increase in soil CO_(2)fluxes from the maize field,with annual increases observed,but a reduction in soil CO_(2)fluxes from the sunflower field.The sunflower fields in the HID have a more substantial advantage than the corn fields in mitigating soil CO_(2)emissions. 展开更多
关键词 Soil CO_(2)flux Nitrogen fertilization rate SUNFLOWER Washing salts by irrigation Rising temperature DAYCENT model Hetao Irrigation District
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Optimization of fertilization combined with water-saving irrigation improves the water and nitrogen utilization efficiency of wheat and reduces nitrogen loss in the Nansi Lake basin,China
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作者 Jingyi Feng He Zhang +8 位作者 Hongyuan Zhang Xirui Kang Hui Wang Hong Pan Quangang Yang Zhongchen Yang Yajie Sun Yanhong Lou Yuping Zhuge 《Journal of Integrative Agriculture》 2025年第10期4034-4047,共14页
The eutrophication of rivers and lakes is becoming increasingly common,primarily because of pollution from agricultural non-point sources.We investigated the effects of optimized water and fertilizer treatments on agr... The eutrophication of rivers and lakes is becoming increasingly common,primarily because of pollution from agricultural non-point sources.We investigated the effects of optimized water and fertilizer treatments on agricultural non-point source pollution in the Nansi Lake basin.The water heat carbon nitrogen simulator model(WHCNS model)was used to analyze water and nitrogen transport in wheat fields in Nansi Lake basin.Four water and fertilizer treatments were set up:conventional fertilization and irrigation(CK),reduced controlled-release fertilizer and conventional irrigation(F2W1),an equal amount of controlled-release fertilizer and reduced irrigation(F1W2),and reduced controlled-release fertilizer and reduced irrigation(F2W2).The results indicated that the replacement of conventional fertilizers with controlled-release fertilizers,combined with reduced irrigation,led to reduced nitrogen loss.Compared with those of the CK,the cumulative nitrogen leaching and ammonia volatilization of F2W1 were reduced by 8.90 and 41.67%,respectively;under F1W2,the same parameters were reduced by 12.50 and 15.99%,respectively.Compared with the other treatments,F2W2 significantly reduced nitrogen loss while producing a stable yield.Compared with those of the CK,ammonia volatilization and nitrogen loss due to leaching were reduced by 29.17 and 27.13%,respectively,water and nitrogen use efficiencies increased by 11.38 and 17.80%,respectively.F2W2 showed the best performance among the treatments,considering water and fertilizer management.Our findings highlight the effectiveness of optimizing water and fertilizer application in improving the water and nitrogen use efficiency of wheat,which is of great significance for mitigating nitrogen loss from farmland in the Nansi Lake basin. 展开更多
关键词 controlled-release fertilizer reduced irrigation WHCNS model nitrogen loss
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白浆层培肥机螺旋排肥器的设计与试验
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作者 李晓明 王秋菊 +5 位作者 张海滨 齐忠军 兰海涛 邹雪剑 陈维刚 梁玉成 《农机化研究》 北大核心 2026年第4期18-24,33,共8页
针对传统排肥器施肥不均匀、效率低等问题,设计了一种白浆层培肥机的螺旋排肥器。其通过精确控制绞龙叶片的数量、螺距和转速,实现了对施肥量的精准调节。利用三维软件SolidWorks 2020对螺旋排肥器建模,通过EDEM软件建立颗粒模型,并进... 针对传统排肥器施肥不均匀、效率低等问题,设计了一种白浆层培肥机的螺旋排肥器。其通过精确控制绞龙叶片的数量、螺距和转速,实现了对施肥量的精准调节。利用三维软件SolidWorks 2020对螺旋排肥器建模,通过EDEM软件建立颗粒模型,并进行虚拟仿真试验。以施肥量稳定性变异系数和均匀性变异系数为指标,结合肥料特性等因素,进行三因素三水平正交试验。采用Design-Expert分析软件对试验数据进行分析,得出最优结构参数:绞龙叶片数量为3,螺距为43 mm,绞龙叶片转速为200 r/min。此时,稳定性变异系数为1.6%,均匀性变异系数为4.51%。剔除不显著因素,建立了施肥量稳定性变异系数和均匀性变异系数的回归方程。田间试验验证表明:试验结果与仿真结果一致,符合NY/T 1003—2006《施肥机械质量评价技术规范》标准,为农业生产提供了可靠的技术支持。 展开更多
关键词 螺旋排肥器 白浆层培肥机 EDEM 变量施肥
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中国生育推迟的特征及其对生育水平的影响
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作者 王强 李婷 《人口学刊》 北大核心 2026年第1期84-98,共15页
时期生育水平的下降深受生育推迟的影响。平均生育年龄能够量化生育推迟的程度,但不同计算方法下平均生育年龄的变化在各个时期存在差异。计算去进度效应生育水平依赖于时期间平均生育年龄的变化,故利用单一平均生育年龄指标讨论进度效... 时期生育水平的下降深受生育推迟的影响。平均生育年龄能够量化生育推迟的程度,但不同计算方法下平均生育年龄的变化在各个时期存在差异。计算去进度效应生育水平依赖于时期间平均生育年龄的变化,故利用单一平均生育年龄指标讨论进度效应的大小可能会错估时期生育水平变化中进度效应的影响。本研究采用队列视角下截断年龄一孩累积生育率观察生育推迟的进度和模式。2020年时中国女性的累积生育进度较快,但随年龄下降而快速走低,这表明年轻队列女性生育行为与早期出生队列存在明显差异。若中国年轻队列女性均依照早期出生队列在2020年时期一孩递进比进行生育,预期的一孩生育水平依然较高。这意味着中国年轻队列女性在2020年时的累积生育进度依然较快,其在未来生育推迟的空间非常大。本文基于全球多地区的生育推迟模式,利用不同生育推迟的拐点年龄和拐点年龄对应的累积一孩生育水平设置不同的推迟轨迹,讨论各类情景下中国未来时期生育水平的走势。结果显示在不考虑生育意愿变动的情况下,未来中国生育水平的走势会在相当程度上受到生育推迟轨迹模式的影响。生育推迟涵盖的年龄段越长、累积生育进度更慢,中国生育水平下降趋势的持续时间也会更长、拐点时期的生育率水平也将更低。若年轻队列生育推迟遵循35岁累积一孩生育水平下降至0.5的深度推迟情境下,中国生育水平整体的下降趋势可能会持续至2027年,总和生育率的最低值可能会下降至0.83且直到2030年后才有明显的补偿效应。中国在近些年出台了一系列旨在提升生育水平的政策,但时期生育水平的走势不仅受生育政策的影响,还取决于进度效应的作用。准确理解时期生育水平变化中进度效应的作用大小对于准确评估生育政策的效应具有重要意义。因为短期内生育水平持续降低并不意味着生育支持政策无效,有可能是政策的积极效果小于进度效应的消极影响,而长期生育率回弹也并非完全是积极生育政策的效应,其中有进度效应补偿生育的作用。 展开更多
关键词 生育推迟 生育水平 进度效应 平均生育年龄 生育政策
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氮磷钾配施对宜机收芝麻产量的影响及肥料效应研究
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作者 李丰 王东勇 +6 位作者 张鹏钰 田媛 戎亚思 郑飞娜 秦海霞 费高亮 高桐梅 《中国土壤与肥料》 北大核心 2026年第1期140-148,共9页
为了探明氮、磷、钾不同配施对宜机收芝麻产量和经济效益的影响及肥料效应,加快宜机收芝麻品种在河南省的推广应用。以宜机收芝麻豫芝ND837和豫芝NS610为试验材料,采用“3414”试验设计进行田间试验,分析不同氮、磷、钾施用量和配比下... 为了探明氮、磷、钾不同配施对宜机收芝麻产量和经济效益的影响及肥料效应,加快宜机收芝麻品种在河南省的推广应用。以宜机收芝麻豫芝ND837和豫芝NS610为试验材料,采用“3414”试验设计进行田间试验,分析不同氮、磷、钾施用量和配比下宜机收芝麻豫芝ND837和豫芝NS610的农艺性状、产量、经济效益及肥料效应。结果表明,氮、磷、钾肥合理配施能有效促进芝麻生长发育,协调单株蒴数、单蒴粒数及千粒重等性状,进而提高芝麻产量。豫芝ND837和豫芝NS610均以N2P2K2处理产量和净收益最高,产量和净收益分别较N0P0K0处理增加48.62%和33.87%,30.72%和15.41%,N2P2K2处理的肥料贡献率分别达到32.7%和25.3%;氮、磷、钾肥对豫芝ND837产量的影响表现为氮肥>磷肥>钾肥,对豫芝NS610产量影响表现为氮肥>钾肥>磷肥;通过肥料效应函数拟合分析,氮、磷、钾肥三元二次肥料效应模型拟合度好,经济效益高,可作为河南省宜机收芝麻推荐施肥模式。豫芝ND837的最佳施肥量为N 131.6 kg/hm^(2)、P_(2)O_(5)98.7 kg/hm^(2)、K_(2)O 116.3 kg/hm^(2),适宜的氮、磷、钾比例为1∶0.75∶0.88;豫芝NS610的最佳施肥量为N 112.8 kg/hm^(2)、P_(2)O_(5)73.9 kg/hm^(2)、K_(2)O 95.4 kg/hm^(2),适宜的氮、磷、钾比例为1∶0.66∶0.85。 展开更多
关键词 氮、磷、钾肥 宜机收芝麻 产量 经济效益 肥料效应
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我国生育力保存研究的可视化分析
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作者 李霞 张倩 +1 位作者 张艳 王慧 《循证护理》 2026年第4期819-826,共8页
目的:分析我国生育力保存相关研究的现状、热点及发展趋势,为该领域的进一步研究提供参考。方法:检索建库至2024年12月31日中国知网发表的生育力保存相关文献,使用CiteSpace 6.4.R1软件对文献作者、机构、关键词进行可视化分析。结果:... 目的:分析我国生育力保存相关研究的现状、热点及发展趋势,为该领域的进一步研究提供参考。方法:检索建库至2024年12月31日中国知网发表的生育力保存相关文献,使用CiteSpace 6.4.R1软件对文献作者、机构、关键词进行可视化分析。结果:共纳入483篇文献,年发文量总体呈上升趋势。该领域形成的科研团队之间合作较少;机构间的合作多为同一医学院校附属医院;研究热点为生育力保存技术的应用以及辅助生殖技术的应用及优化。卵母细胞体外成熟是生育力保存领域的前沿研究方向。生育力保存的对象不只限于恶性肿瘤、不孕不育病人,而是逐步扩展到可能因疾病影响生育功能的人群。病人生育力保存的真实体验、生育决策等正日益成为研究者广泛关注的焦点。结论:虽然生育力保存的研究已受到越来越多研究者的关注和重视,但仍应加强跨机构、跨地区合作,进一步加强学术交流与合作,提升生育力保存研究的质量和影响力。 展开更多
关键词 生育力 生育力保存 生育决策 辅助生殖技术 护理
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