A pot culture experiment was carried out in a glasshouse to compare the physiology and growth of sweet corn plants (Zea mays L. cv. Honey Bantam) grown under organic and chemical fertilizations with or without microbi...A pot culture experiment was carried out in a glasshouse to compare the physiology and growth of sweet corn plants (Zea mays L. cv. Honey Bantam) grown under organic and chemical fertilizations with or without microbial inoculation (MI). The organic fertilizer used was fermented mainly using rice bran and oil mill sludge, and the MI was a liquid product containing many beneficial microbes such as lactic acid bacteria, yeast, photosynthetic bacteria and actinomycetes. The application amounts of the organic fertilizer and chemical fertilizers were based on the same rate of nitrogen, phosphorus and potassium. Sweet corn plants fertilized with organic materials inoculated with beneficial microbes grew better than those without inoculation. There were no significant differences in physiology and growth of the sweet corn plants between treatments of chemical fertilizers with and without MI. Among the organic fertilization treatments, only the sweet corn plants with organic fertilizer and MI applied 4 weeks before sowing had similar photosynthetic capacityj total dry matter yield and ear yield to those with chemical fertilizers. Sweet corn plants in other organic fertilization treatments were weaker in physiology and growth than those in chemical fertilization treatments. There was no significant variance among chemical fertilization treatments at different time. It is concluded from this research that this organic fertilizer would be more effective if it was inoculated with the beneficial microbes. Early application of the organic fertilizer with beneficial microbes before sowing was recommended to make the nutrients available before the rapid growth at the early stage and obtain a yield similar to or higher than that with chemical fertilizations.展开更多
The improvement of soil productivity depends on a rational input of water and nutrients, optimal field management, and the increase of basic soil productivity（BSP）. In this study, BSP is defined as the productive ca...The improvement of soil productivity depends on a rational input of water and nutrients, optimal field management, and the increase of basic soil productivity（BSP）. In this study, BSP is defined as the productive capacity of a farmland soil with its own physical and chemical properties for a specific crop season under local field management. Based on 19-yr data of the long-term agronomic experiments（1989–2008） on a fluvo-aquic soil in Zhengzhou, Henan Province, China, the decision support system for agrotechnology transfer（DSSAT ver. 4.0） crop growth model was used to simulate yields by BSP of winter wheat（Triticum aestivium L.） and summer maize（Zea mays L.） to examine the relationship between BSP and soil organic carbon（SOC） under long-term fertilization. Five treatments were included：（1） no fertilization（control）,（2） nitrogen, phosphorus and potassium fertilizers（NPK）,（3） NPK plus manure（NPKM）,（4） 1.5 times of NPKM（1.5NPKM）, and（5） NPK plus straw（NPKS）. After 19 yr of treatments, the SOC stock increased 16.7, 44.2, 69.9, and 25.2% under the NPK, NPKM, 1.5NPKM, and NPKS, respectively, compared to the initial value. Among various nutrient factors affecting contribution percentage of BSP to winter wheat and summer maize, SOC was a major affecting factor for BSP in the fluvo-aquic soil. There were significant positive correlations between SOC stock and yields by BSP of winter wheat and summer maize（P〈0.01）, and yields by BSP of winter wheat and summer maize increased 154 and 132 kg ha^（–1） when SOC stock increased 1 t C ha^（–1）. Thus, increased SOC accumulation is a crucial way for increasing BSP in fluvo-aquic soil. The manure or straw combined application with chemical fertilizers significantly enhanced BSP compared to the application of chemical fertilizers alone.展开更多
Effects of organic fertilizers and effective microbes on leaf water retention of sweet corn (Zea mays L. cv.Honey-Bantam) were studied. Sweet corns were grown with organic or chemical fertilizers with or without effec...Effects of organic fertilizers and effective microbes on leaf water retention of sweet corn (Zea mays L. cv.Honey-Bantam) were studied. Sweet corns were grown with organic or chemical fertilizers with or without effective microbes (EM). A water retention curve was obtained by drying the excised leaves under a light of 500 μmol (m2·s)-1. The curve shows two distinct phases. The initial steep slope indicates the water loss speed by stomatal transpiration (Est) and the gentle slope of the second phase indicates water loss speed by cuticular transpiration (Ecu). Both Est and Ecu were lower for leaves of plants grown with organic materials than for those with chemical fertilizers. Addition of EM to both organic and chemical fertilizers decreased Est but showed no effect on Ecu. The water retention ability of the excised leaves was proportional to photosynthetic maintenance ability under soil water deficit conditions as well as the solute concentration in leaves. The results suggested that organic fertilization and EM application increased water stress resistance both under in situ conditions and in excised leaves of sweet corn plants.展开更多
Kiwifruit yield and quality and soil nutrients were investigated in a kiwifruit orchard after long-term fertilization to understand the relationship between kiwifruit growth and soil nutrition.Seven fertilization trea...Kiwifruit yield and quality and soil nutrients were investigated in a kiwifruit orchard after long-term fertilization to understand the relationship between kiwifruit growth and soil nutrition.Seven fertilization treatments with three replications were applied in a continuous four-year period,including no fertilizer(CK);phosphorus(P)and potassium(K)fertilizers(PK);N and K fertilizers(NK);N and P fertilizers(NP);N,P and K fertilizers(NPK);1.5 times of N,P and K fertilizers(1.5NPK);and chemical fertilizers plus swine manure(NPKM).Fertilization increased kiwifruit yield at the rate of 450 kg N/hm^(2),225 kg P2O5/hm^(2),300 kg K2O/hm^(2).The average yield decreased in a descending order for NPKM(44.6 t/hm^(2)),1.5NPK(42.6 t/hm^(2)),NPK(42.0 t/hm^(2)),NK(38.0 t/hm^(2)),NP(36.7 t/hm^(2)),PK(36.4 t/hm^(2))and CK(34.1 t/hm^(2)).The sugar to acid ratio(S:A)was the highest(10.9)in 2012,and the soluble sugar increased by 15.7%after four-year NPKM fertilization.The NPKM fertilization also significantly increased the vitamin C,soluble solid and firmness.The soil organic carbon contents at 0-20 cm,20-40 cm and 40-60 cm in depth under the NPKM treatment were 27%,29%and 139%higher than that of the CK treatment,respectively.The available N contents at 0-20 cm,20-40 cm and 40-60 cm in depth in the 1.5NPK treatment were 180%,114%and 133%higher than that in the CK treatment,respectively.Balanced fertilization with N,P,K and organic manure is important to soil fertility,which may increase yield and improve quality in field-grown kiwifruit orchard.展开更多
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
Topsoil soil organic carbon(SOC) data were collected from long-term Chinese agro-ecosystem experiments presented in 76 reports with measurements over 1977 and 2006.The data set comprised 481 observations(135 rice padd...Topsoil soil organic carbon(SOC) data were collected from long-term Chinese agro-ecosystem experiments presented in 76 reports with measurements over 1977 and 2006.The data set comprised 481 observations(135 rice paddies and 346 dry croplands) of SOC under different fertilization schemes at 70 experimental sites(28 rice paddies and 42 dry croplands).The data set covered 16 dominant soil types found in croplands across 23 provinces of China's Mainland.The fertilization schemes were grouped into six categories:N(inorganic nitrogen fertilizer only),NP(compound inorganic nitrogen and phosphorus fertilizers),NPK(compound inorganic nitrogen,phosphorus and potassium fertilizers),O(organic fertilizers only),OF(combined inorganic/organic fertilization) and Others(other unbalanced fertilizations such as P only,K only,P plus K and N plus K).Relative change in SOC content was analyzed,and rice paddies and dry croplands soils were compared.There was an overall temporal increase in topsoil SOC content,and relative annual change(RAC,g kg-1 yr-1) ranged -0.14-0.60(0.13 on average) for dry cropland soils and -0.12-0.70(0.19 on average) for rice paddies.SOC content increase was higher in rice paddies than in dry croplands.SOC increased across experimental sites,but was higher under organic fertilization and combined organic/inorganic fertilizations than chemical fertilizations.SOC increase was higher under balanced chemical fertilizations with compound N,P and K fertilizers than unbalanced fertilizations such as N only,N plus P,and N plus K.The effects of specific rational fertilizations on SOC increase persisted for 15 years in dry croplands and 20 years in rice paddies,although RAC values decreased generally as the experiment duration increased.Therefore,the extension of rational fertilization in China's croplands may offer a technical option to enhance C sequestration potential and to sustain long-term crop productivity.展开更多
Differently sized soil aggregates,with non-uniform distribution of space and nutrients,provide spatially heterogeneous microenvironments for microorganisms and are important for controlling microbial community ecology...Differently sized soil aggregates,with non-uniform distribution of space and nutrients,provide spatially heterogeneous microenvironments for microorganisms and are important for controlling microbial community ecology and biogeochemistry in soils.Here,we investigated the prokaryotic communities within different aggregate-size fractions:macroaggregate(>0.25 mm),microaggre-gate(0.053–0.25 mm)and silt+clay(<0.053 mm).These were isolated from fluvo-aquic soils under 39-year fertilization strategies:no fertilizer(CK),chemical fertilizer(NPK),manure fertilizer(M),and combination of manure and chemical fertilizers(MNPK).The results showed that the proportion of macroaggregate,soil aggregate-associated organic carbon(SOC)content and aggregate stability were all significantly increased by both manure and chemical fertilizations.Organic fertilizations(M and MNPK)more effectively boosted formation and stability of macroaggregates and enhanced SOC concentration than NPK.The distribution patterns of microorganisms in aggregates were primarily shaped by fertilization and aggregate size.They explained 76.9%of the variance in bacterial community compositions.Fertilizations,especially with organic fertilizers primarily transitioned bacterial communities from slow-growing oligotrophic groups(e.g.,Chloroflexi)dominance to fast-growing copiotrophic groups(e.g.,Proteobacteria and Bacteroidetes)dominance across all aggregate sizes.Macroaggregates possessed a more stable bacterial community and efficiency of resource transfer,while smaller aggregates increased antagonism and weakened mutualism among bacterial communities.Overall,combination of manure and chemical fertilizers was crucial for increasing SOC content and aggregation,leading to a clear shift in bacterial community structures at aggregate scale.展开更多
Agricultural practices significantly contribute to greenhouse gas(GHG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize production.Plastic film mulc...Agricultural practices significantly contribute to greenhouse gas(GHG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize production.Plastic film mulching is commonly used in the Loess Plateau region.Incorporating slow-release fertilizers as a replacement for urea within this practice can reduce nitrogen losses and enhance crop productivity.Combining these techniques represents a novel agricultural approach in semi-arid areas.However,the impact of this integration on soil carbon storage(SOCS),carbon footprint(CF),and economic benefits has received limited research attention.Therefore,we conducted an eight-year study(2015-2022)in the semi-arid northwestern region to quantify the effects of four treatments[urea supplied without plastic film mulching(CK-U),slow-release fertilizer supplied without plastic film mulching(CK-S),urea supplied with plastic film mulching(PM-U),and slow-release fertilizer supplied with plastic film mulching(PM-S)]on soil fertility,economic and environmental benefits.The results revealed that nitrogen fertilizer was the primary contributor to total GHG emissions(≥71.97%).Compared to other treatments,PM-S increased average grain yield by 12.01%-37.89%,water use efficiency by 9.19%-23.33%,nitrogen accumulation by 27.07%-66.19%,and net return by 6.21%-29.57%.Furthermore,PM-S decreased CF by 12.87%-44.31%and CF per net return by 14.25%-41.16%.After eight years,PM-S increased SOCS(0-40 cm)by 2.46%,while PM-U decreased it by 7.09%.These findings highlight the positive effects of PM-S on surface soil fertility,economic gains,and environmental benefits in spring maize production on the Loess Plateau,underscoring its potential for widespread adoption and application.展开更多
Both straw incorporation and irrigation practices affect biological nitrogen(N)fixation(BNF),but it is still unclear how straw incorporation impacts BNF under continuous(CFI)or intermittent(IFI)flooding irrigation in ...Both straw incorporation and irrigation practices affect biological nitrogen(N)fixation(BNF),but it is still unclear how straw incorporation impacts BNF under continuous(CFI)or intermittent(IFI)flooding irrigation in a rice cropping system.A15N2-labeling chamber system was placed in a rice field to evaluate BNF with straw incorporation under CFI or IFI for 90 d.The nif H(gene encoding the nitrogenase reductase subunit)DNA and c DNA in soil were amplified using real-time quantitative polymerase chain reaction,and high-throughput sequencing was applied to the nif H gene.The total fixed N in the straw incorporation treatment was 14.3 kg ha^(-1)under CFI,being 116%higher than that under IFI(6.62 kg ha^(-1)).Straw incorporation and CFI showed significant interactive effects on the total fixed N and abundances of nif H DNA and c DNA.The increase in BNF was mainly due to the increase in the abundances of heterotrophic diazotrophs such as Desulfovibrio,Azonexus,and Azotobacter.These results indicated that straw incorporation stimulated BNF under CFI relative to IFI,which might ultimately lead to a rapid enhancement of soil fertility.展开更多
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
Whilst phosphorus(P)in soil is considered to be abundant,the portion available for plant uptake constitutes less than 1%of the overall P present.To enhance crop productivity,the utilization of mineral P fertilizers ha...Whilst phosphorus(P)in soil is considered to be abundant,the portion available for plant uptake constitutes less than 1%of the overall P present.To enhance crop productivity,the utilization of mineral P fertilizers has become pervasive in agriculture.Nonetheless,the escalating prices of chemical fertilizers,coupled with new European regulations prohibiting the use of P fertilizers containing cadmium,have highlighted the urgency to identify environmentally friendly products and practices for P fertilization in agricultural soils.This comprehensive review delves into the current landscape of P fertilization from agricultural,political,and economic standpoints.We recognize the potential of microbes in mobilizing P,but emphasize the necessity for more robust research to establish their effectiveness in promoting plant P uptake under real-world conditions.Additionally,we explore the role of agricultural conservation practices,such as optimal tillage,diversified cropping systems,and increased organic carbon input,in conserving P.Furthermore,this review contemplates forthcoming innovations in research.These innovations encompass the development of enhanced formulations for biofertilizers and the undertaking of more comprehensive studies within the realm of conservation agriculture.All these endeavors collectively hold the potential to augment P accessibility to plants in a sustainable manner,thereby advancing agricultural sustainability and productivity.展开更多
The trade-off between yield and environmental effects caused by nitrogen fertilizer application is an important issue in wheat production.A reduction in fertile florets is one of the main reasons for the lower yields ...The trade-off between yield and environmental effects caused by nitrogen fertilizer application is an important issue in wheat production.A reduction in fertile florets is one of the main reasons for the lower yields under low nitrogen application rates.Brassinosteroids(BRs)have been found to play a role in nitrogen-induced rice spikelet degeneration.However,whether BRs play a role in wheat floret development and the mechanisms involved are not clear.Therefore,a nitrogen gradient experiment and exogenous spraying experiment were conducted to investigate the role and mechanism of BRs in wheat floret development under low nitrogen stress.The results showed that as the nitrogen application decreased,the endogenous BRs content of the spikes decreased,photosynthesis weakened,and total carbon,soluble sugar and starch in the spikes decreased,leading to a reduction in the number of fertile florets.Under low nitrogen stress,exogenous spraying of 24-epibrassinolide promoted photosynthesis,and stimulated stem fructan hydrolysis and the utilization and storage of sucrose in spikes,which directed more carbohydrates to the spikes and increased the number of fertile florets.In conclusion,BRs mediate the effects of nitrogen fertilizer on wheat floret development,and under low nitrogen stress,foliar spraying of 24-epibrassinolide promotes the flow of carbohydrates from the stem to the spikes,alleviating wheat floret degeneration.展开更多
Objective Selective estrogen receptor modulators(SERMs)have demonstrated efficacy in the treatment of hypogonadism in males and male factor infertility.Two SERMs,clomiphene citrate and tamoxifen,are now prescribed for...Objective Selective estrogen receptor modulators(SERMs)have demonstrated efficacy in the treatment of hypogonadism in males and male factor infertility.Two SERMs,clomiphene citrate and tamoxifen,are now prescribed for off-label use to treat both conditions in males.However,existing literature compares mixed protocols with active management.We aimed to conduct a meta-analysis to evaluate the effect of clomiphene and tamoxifen versus placebo on natural pregnancy rates.Methods We conducted a comprehensive systematic review of electronic databases:MEDLINE,PubMed/PMC,EMBASE,CINAHL,Cochrane Central Register of Controlled Trials(CENTRAL),Scopus,Google Scholar,and Web of Science.Articles satisfying all selection criteria were analyzed.The primary outcome was the incidence of pregnancy after receiving the treatment.Secondary outcomes included serum follicle-stimulating hormone,luteinizing hormone,and testosterone levels,and sperm count and motility.We calculated the pooled odds ratio,risk ratio,and risk difference to ascertain possible alterations in the direction of the pooled effect size.Results Ten randomized controlled trials were ultimately included and underwent data extraction.Clomiphene citrate and placebo groups had similar pregnancy rates(10.4%and 7.1%,respectively;odds ratio 1.30[95%confidence interval 0.27–6.17];p=0.74).No meta-analysis could be calculated for pregnancy rates in tamoxifen versus placebo groups.Heterogeneity among the studies of both SERMs ranged from low to high.Conclusion Although clomiphene citrate and tamoxifen are often used off-label for the treatment of male infertility secondary to hypogonadism,studies of SERMs in the treatment of idiopathic male factor infertility are limited and heterogenous,preventing this meta-analysis from investigating the efficacy of SERMs on male infertility.The effect of clomiphene citrate or tamoxifen on the pregnancy rate remains uncertain.展开更多
Organic material combined with inorganic fertilizer has been shown to greatly improve crop yield and maintain soil fertility globally. However, it remains unclear if crop yield and soil fertility can be sustained in t...Organic material combined with inorganic fertilizer has been shown to greatly improve crop yield and maintain soil fertility globally. However, it remains unclear if crop yield and soil fertility can be sustained in the long term under the combined application of organic and inorganic fertilizers. Three long-term field trials were conducted to investigate the effects of organic amendments on the grain sustainable yield index(SYI), soil fertility index(SFI)and nutrient balance in maize–wheat cropping systems of central and southern China during 1991–2019. Five treatments were included in the trials: 1) no fertilization(control);2) balanced mineral fertilization(NPK);3) NPK plus manure(NPKM);4) high dose of NPK plus manure(1.5NPKM);and 5) NPK plus crop straw(NPKS). Over time, the grain yields of wheat and maize showed an increasing trend in all four fertilization treatments at the Yangling(YL) and Zhengzhou(ZZ) locations, while they declined at Qiyang(QY). The grain yield in the NPKM and 1.5NPKM treatments gradually exceeded that of the NPK and NPKS treatments at the QY site. The largest SYI was recorded in the NPKM treatment across the three sites, suggesting that inorganic fertilizer combined with manure can effectively improve crop yield sustainability. Higher SYI values were recorded at the YL and ZZ sites than at the QY site, possibly because the soil was more acid at QY. The key factors affecting grain yield were soil available phosphorus(AP) and available potassium(AK) at the YL and ZZ sites, and pH and AP at the QY site.All fertilization treatments resulted in soil N and P surpluses at the three sites, but soil K surpluses were recorded only at the QY site. The SFI was greater in the 1.5NPKM, NPKM and NPKS treatments than in the NPK treatment by 13.3–40.0 and 16.4–63.6% at the YL and ZZ sites, respectively, and was significantly higher in the NPKM and 1.5NPKM treatments than in the NPK and NPKS treatments at the QY site. A significant, positive linear relationship was found between SFI and crop yield, and SYI and nutrient balance, indicating that grain yield and its sustainability significantly increased with increasing soil fertility. The apparent N, P and K balances positively affected SFI.This study suggests that the appropriate amount of manure mixed with mineral NPK fertilizer is beneficial to the development of sustainable agriculture, which effectively increases the crop yield and yield sustainability by improving soil fertility.展开更多
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
Both soil organic carbon (SOC) and iron (Fe) oxide content, among other factors, drive the formation and stability of soil aggregates.However, the mechanism of these drivers in greenhouse soil fertilized with organic ...Both soil organic carbon (SOC) and iron (Fe) oxide content, among other factors, drive the formation and stability of soil aggregates.However, the mechanism of these drivers in greenhouse soil fertilized with organic fertilizer is not well understood.In a 3-year field experiment, we aimed to investigate the factors which drive the stability of soil aggregates in greenhouse soil.To explore the impact of organic fertilizer on soil aggregates, we established four treatments:no fertilization (CK);inorganic fertilizer (CF);organic fertilizer (OF);and combined application of inorganic and organic fertilizers(COF).The application of organic fertilizer significantly enhanced the stability of aggregates, that is it enhanced the mean weight diameter, geometric mean diameter and aggregate content (%) of>0.25 mm aggregate fractions.OF and COF treatments increased the concentration of SOC, especially the aliphatic-C, aromatic-C and polysaccharide-C components of SOC, particularly in>0.25 mm aggregates.Organic fertilizer application significantly increased the content of free Fe(Fed), reactive Fe (Feo), and non-crystalline Fe in both bulk soil and aggregates.Furthermore, non-crystalline Fe showed a positive correlation with SOC content in both bulk soil and aggregates.Both non-crystalline Fe and SOC were significantly positively correlated with>2 mm mean weight diameter.Overall, we believe that the increase of SOC, aromatic-C, and non-crystal ine Fe concentrations in soil after the application of organic fertilizer is the reason for improving soil aggregate stability.展开更多
To promote the growth of cutting seeding of poplar(Populus L.),nitrogen(N)fertilizer and surface weed managements were required.We here conducted a pot experiment to examine the effects of natural vegetation,barnyardg...To promote the growth of cutting seeding of poplar(Populus L.),nitrogen(N)fertilizer and surface weed managements were required.We here conducted a pot experiment to examine the effects of natural vegetation,barnyardgrass(Echinochloa Beauv.),and sesbania(Sesbania cannabina pers.)on the growth of poplar cutting seedlings,soil properties,and ammonia(NH3)volatilization under three N inputs(0,0.5,and 1.5 g/pot,i.e.,N0,N0.5,and N1,respectively).Results showed that N application promoted the growth of poplar cutting seedlings,including plant height,ground diameter,and biomass,compared with N0 treatment.Moreover,under N0,sesbania significantly increased the plant height by 87.1%,barnyardgrass and sesbania significantly increased the ground diameter(16.2%and 51.5%),and biomass(67.4%and 74.7%)of poplar cutting seedlings,compared with natural vegetation management.Compared to natural vegetation,soil organic matter(SOM)of barnyardgrass and sesbania covered soil significantly increased by 12.4%and 18.7%at N1,respectively.In addition,soil total N(TN)content was significantly increased by 15.8%in barnyardgrass planted at N0.The soil ammonium N(NH_(4)^(+)-N)content decreased with the planting of barnyardgrass and sesbania across all levels of N application.At N0.5,the nitrate N(NO_(3)^(−)-N)content of soil planted with barnyardgrass significantly increased compared to both the natural vegetation and the sesbania groups.Compared to the natural vegetation,the soil available phosphorus(AP)content of the barnyardgrass group significantly increasing by 78.8%at N0.5,soil available potassium(AK)content was significantly reduced by 12.5%in the sesbania group at N0 and increased by 24.1%in the barnyardgrass group at N1.We found that cumulative NH3 emissions were significantly higher in all treatment groups at the N1 level than that at the N0.5 level,while the differences among the three plants treated were not significant.The results suggest that both barnyardgrass and sesbania promote seedling growth in the short term,while also increase certain properties.Therefore,effective herb management during the seedling stage is recommended in nurseries to support seedling growth and retain soil fertility.展开更多
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
Cyclosporin A fermentation residue(CFR)is a type of organic waste generated during the production of cyclosporin A,which are abundant in nutrients including organic matter,phosphorus,nitrogen and potassium.Inappropria...Cyclosporin A fermentation residue(CFR)is a type of organic waste generated during the production of cyclosporin A,which are abundant in nutrients including organic matter,phosphorus,nitrogen and potassium.Inappropriate handling of CFR not only waste valuable bioresources,but may also lead to the cyclosporin A and associated resistance genes into the natural environment,posing a significant threat to ecological system and human health.Land application was an effective way to resource recovery of CFR after aerobic composting(CAC).This study investigated the impact of CAC on soil fertility and environmental safety.The results indicated that CAC could improve soil nutrient contents and enhance enzyme activities.CAC altered the diversity and community composition of soil bacteria,resulting in an increase in the abundance of relevant bacteria beneficial for organic matter decomposition and cyclosporin A degradation.The introduced cyclosporin A(71.69μg/kg)completely degraded within 20 days due to soil biodegradation.The significantly increased abundance of intIl,mdr3,pgp,TSR and pmra in the soil cultivation early stage were restored to the soil background level within 90 days,indicating a reduced risk of antimicrobial resistance.The results demonstrated that reasonable land application of CAC could improve soil fertility without antimicrobial resistance risk,which is helpful for evaluating the resource utilization value and environmental risks of antibiotic fermentation residue after aerobic composting.展开更多
The application of organic fertilizers has become an increasingly popular practice in maize production to reduce thegaseous nitrogen(N) loss and soil degradation caused by inorganic fertilizers. Organic fertilizer pla...The application of organic fertilizers has become an increasingly popular practice in maize production to reduce thegaseous nitrogen(N) loss and soil degradation caused by inorganic fertilizers. Organic fertilizer plays a key rolein improving soil quality and stabilizing maize yields, but few studies have compared different substitution rates. Afield study was carried out in 2021 and 2022, based on a long-term trial initiated in 2016, which included five organicfertilizer N substitution rates with equal inputs of 200 kg N ha^(–1): 0% organic fertilizer(T1, 100% inorganic fertilizer),50.0% organic+50.0% inorganic fertilizer(T2), 37.5% organic+62.5% inorganic fertilizer(T3), 25.0% organic+75.0%inorganic fertilizer(T4), and 12.5% organic+87.5% inorganic fertilizer(T5), as well as a no fertilizer control(T6). Theresults of the two years showed that T3 and T1 had the highest grain yield and biomass, respectively, and there wasno significant difference between T1 and T3. Compared with T1, the 12.5, 25.0, 37.5, and 50.0% substitution rates in T5, T4, T3, and T2 significantly reduced total nitrogen losses(NH_(3), N_(2)O) by 8.3, 16.1, 18.7, and 27.0%, respectively.Nitrogen use efficiency(NUE) was higher in T5, T3, and T1, and there were no significant differences among them.Organic fertilizer substitution directly reduced NH_(3)volatilization and N_(2)O emission from farmland by lowering theammonium nitrogen and alkali-dissolved N contents and by increasing soil moisture. These substitution treatmentsreduced N_(2)O emissions indirectly by regulating the abundances of AOB and nirK-harboring genes by promotingsoil moisture. Specifically, the 37.5% organic fertilizer substitution reduces NH_(3)volatilization and N_(2)O emission from farmland by reducing the ammonium nitrogen and alkali-dissolved N contents and increasing moisture, which negatively regulate the abundance of AOB and nir K-harboring genes to reduce N_(2)O emissions indirectly in rainfed maize fields on the Loess Plateau of China.展开更多
文摘A pot culture experiment was carried out in a glasshouse to compare the physiology and growth of sweet corn plants (Zea mays L. cv. Honey Bantam) grown under organic and chemical fertilizations with or without microbial inoculation (MI). The organic fertilizer used was fermented mainly using rice bran and oil mill sludge, and the MI was a liquid product containing many beneficial microbes such as lactic acid bacteria, yeast, photosynthetic bacteria and actinomycetes. The application amounts of the organic fertilizer and chemical fertilizers were based on the same rate of nitrogen, phosphorus and potassium. Sweet corn plants fertilized with organic materials inoculated with beneficial microbes grew better than those without inoculation. There were no significant differences in physiology and growth of the sweet corn plants between treatments of chemical fertilizers with and without MI. Among the organic fertilization treatments, only the sweet corn plants with organic fertilizer and MI applied 4 weeks before sowing had similar photosynthetic capacityj total dry matter yield and ear yield to those with chemical fertilizers. Sweet corn plants in other organic fertilization treatments were weaker in physiology and growth than those in chemical fertilization treatments. There was no significant variance among chemical fertilization treatments at different time. It is concluded from this research that this organic fertilizer would be more effective if it was inoculated with the beneficial microbes. Early application of the organic fertilizer with beneficial microbes before sowing was recommended to make the nutrients available before the rapid growth at the early stage and obtain a yield similar to or higher than that with chemical fertilizations.
基金supported by the National Basic Research Program of China(973 Program,2011CB100501)the Key Technologies R&D Program of China during the 12th Five-Year Plan period(2015BAD22B03)+1 种基金the National High-Tech R&D Program of China(2013AA102901)the Special Fund for Agro-scientific Research in the Public Interest,China(201203077)
文摘The improvement of soil productivity depends on a rational input of water and nutrients, optimal field management, and the increase of basic soil productivity（BSP）. In this study, BSP is defined as the productive capacity of a farmland soil with its own physical and chemical properties for a specific crop season under local field management. Based on 19-yr data of the long-term agronomic experiments（1989–2008） on a fluvo-aquic soil in Zhengzhou, Henan Province, China, the decision support system for agrotechnology transfer（DSSAT ver. 4.0） crop growth model was used to simulate yields by BSP of winter wheat（Triticum aestivium L.） and summer maize（Zea mays L.） to examine the relationship between BSP and soil organic carbon（SOC） under long-term fertilization. Five treatments were included：（1） no fertilization（control）,（2） nitrogen, phosphorus and potassium fertilizers（NPK）,（3） NPK plus manure（NPKM）,（4） 1.5 times of NPKM（1.5NPKM）, and（5） NPK plus straw（NPKS）. After 19 yr of treatments, the SOC stock increased 16.7, 44.2, 69.9, and 25.2% under the NPK, NPKM, 1.5NPKM, and NPKS, respectively, compared to the initial value. Among various nutrient factors affecting contribution percentage of BSP to winter wheat and summer maize, SOC was a major affecting factor for BSP in the fluvo-aquic soil. There were significant positive correlations between SOC stock and yields by BSP of winter wheat and summer maize（P〈0.01）, and yields by BSP of winter wheat and summer maize increased 154 and 132 kg ha^（–1） when SOC stock increased 1 t C ha^（–1）. Thus, increased SOC accumulation is a crucial way for increasing BSP in fluvo-aquic soil. The manure or straw combined application with chemical fertilizers significantly enhanced BSP compared to the application of chemical fertilizers alone.
文摘Effects of organic fertilizers and effective microbes on leaf water retention of sweet corn (Zea mays L. cv.Honey-Bantam) were studied. Sweet corns were grown with organic or chemical fertilizers with or without effective microbes (EM). A water retention curve was obtained by drying the excised leaves under a light of 500 μmol (m2·s)-1. The curve shows two distinct phases. The initial steep slope indicates the water loss speed by stomatal transpiration (Est) and the gentle slope of the second phase indicates water loss speed by cuticular transpiration (Ecu). Both Est and Ecu were lower for leaves of plants grown with organic materials than for those with chemical fertilizers. Addition of EM to both organic and chemical fertilizers decreased Est but showed no effect on Ecu. The water retention ability of the excised leaves was proportional to photosynthetic maintenance ability under soil water deficit conditions as well as the solute concentration in leaves. The results suggested that organic fertilization and EM application increased water stress resistance both under in situ conditions and in excised leaves of sweet corn plants.
基金IPNI(International Plant Nutrition Institute),2011collaborative technology innovation in Shaanxi Province(QBXT-Z(P)-15-5)Key Laboratory for Agricultural Environment,Ministry of Agriculture Open Foundation(2015)。
文摘Kiwifruit yield and quality and soil nutrients were investigated in a kiwifruit orchard after long-term fertilization to understand the relationship between kiwifruit growth and soil nutrition.Seven fertilization treatments with three replications were applied in a continuous four-year period,including no fertilizer(CK);phosphorus(P)and potassium(K)fertilizers(PK);N and K fertilizers(NK);N and P fertilizers(NP);N,P and K fertilizers(NPK);1.5 times of N,P and K fertilizers(1.5NPK);and chemical fertilizers plus swine manure(NPKM).Fertilization increased kiwifruit yield at the rate of 450 kg N/hm^(2),225 kg P2O5/hm^(2),300 kg K2O/hm^(2).The average yield decreased in a descending order for NPKM(44.6 t/hm^(2)),1.5NPK(42.6 t/hm^(2)),NPK(42.0 t/hm^(2)),NK(38.0 t/hm^(2)),NP(36.7 t/hm^(2)),PK(36.4 t/hm^(2))and CK(34.1 t/hm^(2)).The sugar to acid ratio(S:A)was the highest(10.9)in 2012,and the soluble sugar increased by 15.7%after four-year NPKM fertilization.The NPKM fertilization also significantly increased the vitamin C,soluble solid and firmness.The soil organic carbon contents at 0-20 cm,20-40 cm and 40-60 cm in depth under the NPKM treatment were 27%,29%and 139%higher than that of the CK treatment,respectively.The available N contents at 0-20 cm,20-40 cm and 40-60 cm in depth in the 1.5NPK treatment were 180%,114%and 133%higher than that in the CK treatment,respectively.Balanced fertilization with N,P,K and organic manure is important to soil fertility,which may increase yield and improve quality in field-grown kiwifruit orchard.
文摘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.
基金supported by the National Natural Science Foundation of China (Grant No. 40710019002)the Ministry of Science and Technology of China (Grant No. 2008BAD95B13-1)the Ministry of Education of China for key basic research projects
文摘Topsoil soil organic carbon(SOC) data were collected from long-term Chinese agro-ecosystem experiments presented in 76 reports with measurements over 1977 and 2006.The data set comprised 481 observations(135 rice paddies and 346 dry croplands) of SOC under different fertilization schemes at 70 experimental sites(28 rice paddies and 42 dry croplands).The data set covered 16 dominant soil types found in croplands across 23 provinces of China's Mainland.The fertilization schemes were grouped into six categories:N(inorganic nitrogen fertilizer only),NP(compound inorganic nitrogen and phosphorus fertilizers),NPK(compound inorganic nitrogen,phosphorus and potassium fertilizers),O(organic fertilizers only),OF(combined inorganic/organic fertilization) and Others(other unbalanced fertilizations such as P only,K only,P plus K and N plus K).Relative change in SOC content was analyzed,and rice paddies and dry croplands soils were compared.There was an overall temporal increase in topsoil SOC content,and relative annual change(RAC,g kg-1 yr-1) ranged -0.14-0.60(0.13 on average) for dry cropland soils and -0.12-0.70(0.19 on average) for rice paddies.SOC content increase was higher in rice paddies than in dry croplands.SOC increased across experimental sites,but was higher under organic fertilization and combined organic/inorganic fertilizations than chemical fertilizations.SOC increase was higher under balanced chemical fertilizations with compound N,P and K fertilizers than unbalanced fertilizations such as N only,N plus P,and N plus K.The effects of specific rational fertilizations on SOC increase persisted for 15 years in dry croplands and 20 years in rice paddies,although RAC values decreased generally as the experiment duration increased.Therefore,the extension of rational fertilization in China's croplands may offer a technical option to enhance C sequestration potential and to sustain long-term crop productivity.
基金This work was funded by the National Natural Science Founda-tion of China(42007076)the Shandong Provincial Natural Science Foundation(ZR2020QD116 and ZR2019BD032)the China Postdoctoral Science Foundation(2020T130387 and 2019M652448).
文摘Differently sized soil aggregates,with non-uniform distribution of space and nutrients,provide spatially heterogeneous microenvironments for microorganisms and are important for controlling microbial community ecology and biogeochemistry in soils.Here,we investigated the prokaryotic communities within different aggregate-size fractions:macroaggregate(>0.25 mm),microaggre-gate(0.053–0.25 mm)and silt+clay(<0.053 mm).These were isolated from fluvo-aquic soils under 39-year fertilization strategies:no fertilizer(CK),chemical fertilizer(NPK),manure fertilizer(M),and combination of manure and chemical fertilizers(MNPK).The results showed that the proportion of macroaggregate,soil aggregate-associated organic carbon(SOC)content and aggregate stability were all significantly increased by both manure and chemical fertilizations.Organic fertilizations(M and MNPK)more effectively boosted formation and stability of macroaggregates and enhanced SOC concentration than NPK.The distribution patterns of microorganisms in aggregates were primarily shaped by fertilization and aggregate size.They explained 76.9%of the variance in bacterial community compositions.Fertilizations,especially with organic fertilizers primarily transitioned bacterial communities from slow-growing oligotrophic groups(e.g.,Chloroflexi)dominance to fast-growing copiotrophic groups(e.g.,Proteobacteria and Bacteroidetes)dominance across all aggregate sizes.Macroaggregates possessed a more stable bacterial community and efficiency of resource transfer,while smaller aggregates increased antagonism and weakened mutualism among bacterial communities.Overall,combination of manure and chemical fertilizers was crucial for increasing SOC content and aggregation,leading to a clear shift in bacterial community structures at aggregate scale.
基金supported by the National Natural Science Foundation of China(No.32071980)the Key Projects of Shaanxi Agricultural Collaborative Innovation and Extension Alliance(No.LMZD202201)+1 种基金the Key R&D Project in Shaanxi Province(No.2021LLRH-07)Shaanxi Natural Scientific Basic Research Program project(No.2022JQ-157).
文摘Agricultural practices significantly contribute to greenhouse gas(GHG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize production.Plastic film mulching is commonly used in the Loess Plateau region.Incorporating slow-release fertilizers as a replacement for urea within this practice can reduce nitrogen losses and enhance crop productivity.Combining these techniques represents a novel agricultural approach in semi-arid areas.However,the impact of this integration on soil carbon storage(SOCS),carbon footprint(CF),and economic benefits has received limited research attention.Therefore,we conducted an eight-year study(2015-2022)in the semi-arid northwestern region to quantify the effects of four treatments[urea supplied without plastic film mulching(CK-U),slow-release fertilizer supplied without plastic film mulching(CK-S),urea supplied with plastic film mulching(PM-U),and slow-release fertilizer supplied with plastic film mulching(PM-S)]on soil fertility,economic and environmental benefits.The results revealed that nitrogen fertilizer was the primary contributor to total GHG emissions(≥71.97%).Compared to other treatments,PM-S increased average grain yield by 12.01%-37.89%,water use efficiency by 9.19%-23.33%,nitrogen accumulation by 27.07%-66.19%,and net return by 6.21%-29.57%.Furthermore,PM-S decreased CF by 12.87%-44.31%and CF per net return by 14.25%-41.16%.After eight years,PM-S increased SOCS(0-40 cm)by 2.46%,while PM-U decreased it by 7.09%.These findings highlight the positive effects of PM-S on surface soil fertility,economic gains,and environmental benefits in spring maize production on the Loess Plateau,underscoring its potential for widespread adoption and application.
基金supported by the National Natural Science Foundation of China(Nos.42177333 and 31870500)the National Special Program for Key Basic Research of the Ministry of Science and Technology of China(No.2015FY110700)the Jiangsu Agriculture Science and Technology Innovation Fund,China(No.JASTIFCX(20)2003)。
文摘Both straw incorporation and irrigation practices affect biological nitrogen(N)fixation(BNF),but it is still unclear how straw incorporation impacts BNF under continuous(CFI)or intermittent(IFI)flooding irrigation in a rice cropping system.A15N2-labeling chamber system was placed in a rice field to evaluate BNF with straw incorporation under CFI or IFI for 90 d.The nif H(gene encoding the nitrogenase reductase subunit)DNA and c DNA in soil were amplified using real-time quantitative polymerase chain reaction,and high-throughput sequencing was applied to the nif H gene.The total fixed N in the straw incorporation treatment was 14.3 kg ha^(-1)under CFI,being 116%higher than that under IFI(6.62 kg ha^(-1)).Straw incorporation and CFI showed significant interactive effects on the total fixed N and abundances of nif H DNA and c DNA.The increase in BNF was mainly due to the increase in the abundances of heterotrophic diazotrophs such as Desulfovibrio,Azonexus,and Azotobacter.These results indicated that straw incorporation stimulated BNF under CFI relative to IFI,which might ultimately lead to a rapid enhancement of soil fertility.
基金National Natural Science Foundation of China,No.41761003The Karst Science Research Center of Guizhou Province,No.U1812401。
文摘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.
基金financed by the Spanish Ministry of Science and Innovation and the European Regional Development Fund(ERDF)(No.PID20211234690BI00)the European Joint Program EJP_Soil(TRACE-Soils)(No.862695)+1 种基金the Spanish Ministry of Science and Innovation(RED2018-102624TMCIN/AEI/10.13039/501100011033)the Project PREPSOIL European Union(No.101070045,HORIZON CSA)。
文摘Whilst phosphorus(P)in soil is considered to be abundant,the portion available for plant uptake constitutes less than 1%of the overall P present.To enhance crop productivity,the utilization of mineral P fertilizers has become pervasive in agriculture.Nonetheless,the escalating prices of chemical fertilizers,coupled with new European regulations prohibiting the use of P fertilizers containing cadmium,have highlighted the urgency to identify environmentally friendly products and practices for P fertilization in agricultural soils.This comprehensive review delves into the current landscape of P fertilization from agricultural,political,and economic standpoints.We recognize the potential of microbes in mobilizing P,but emphasize the necessity for more robust research to establish their effectiveness in promoting plant P uptake under real-world conditions.Additionally,we explore the role of agricultural conservation practices,such as optimal tillage,diversified cropping systems,and increased organic carbon input,in conserving P.Furthermore,this review contemplates forthcoming innovations in research.These innovations encompass the development of enhanced formulations for biofertilizers and the undertaking of more comprehensive studies within the realm of conservation agriculture.All these endeavors collectively hold the potential to augment P accessibility to plants in a sustainable manner,thereby advancing agricultural sustainability and productivity.
基金supported by the Key Research and Development Program of Shaanxi,China(2021NY-083)the National Natural Science Foundation of China(31871567)。
文摘The trade-off between yield and environmental effects caused by nitrogen fertilizer application is an important issue in wheat production.A reduction in fertile florets is one of the main reasons for the lower yields under low nitrogen application rates.Brassinosteroids(BRs)have been found to play a role in nitrogen-induced rice spikelet degeneration.However,whether BRs play a role in wheat floret development and the mechanisms involved are not clear.Therefore,a nitrogen gradient experiment and exogenous spraying experiment were conducted to investigate the role and mechanism of BRs in wheat floret development under low nitrogen stress.The results showed that as the nitrogen application decreased,the endogenous BRs content of the spikes decreased,photosynthesis weakened,and total carbon,soluble sugar and starch in the spikes decreased,leading to a reduction in the number of fertile florets.Under low nitrogen stress,exogenous spraying of 24-epibrassinolide promoted photosynthesis,and stimulated stem fructan hydrolysis and the utilization and storage of sucrose in spikes,which directed more carbohydrates to the spikes and increased the number of fertile florets.In conclusion,BRs mediate the effects of nitrogen fertilizer on wheat floret development,and under low nitrogen stress,foliar spraying of 24-epibrassinolide promotes the flow of carbohydrates from the stem to the spikes,alleviating wheat floret degeneration.
文摘Objective Selective estrogen receptor modulators(SERMs)have demonstrated efficacy in the treatment of hypogonadism in males and male factor infertility.Two SERMs,clomiphene citrate and tamoxifen,are now prescribed for off-label use to treat both conditions in males.However,existing literature compares mixed protocols with active management.We aimed to conduct a meta-analysis to evaluate the effect of clomiphene and tamoxifen versus placebo on natural pregnancy rates.Methods We conducted a comprehensive systematic review of electronic databases:MEDLINE,PubMed/PMC,EMBASE,CINAHL,Cochrane Central Register of Controlled Trials(CENTRAL),Scopus,Google Scholar,and Web of Science.Articles satisfying all selection criteria were analyzed.The primary outcome was the incidence of pregnancy after receiving the treatment.Secondary outcomes included serum follicle-stimulating hormone,luteinizing hormone,and testosterone levels,and sperm count and motility.We calculated the pooled odds ratio,risk ratio,and risk difference to ascertain possible alterations in the direction of the pooled effect size.Results Ten randomized controlled trials were ultimately included and underwent data extraction.Clomiphene citrate and placebo groups had similar pregnancy rates(10.4%and 7.1%,respectively;odds ratio 1.30[95%confidence interval 0.27–6.17];p=0.74).No meta-analysis could be calculated for pregnancy rates in tamoxifen versus placebo groups.Heterogeneity among the studies of both SERMs ranged from low to high.Conclusion Although clomiphene citrate and tamoxifen are often used off-label for the treatment of male infertility secondary to hypogonadism,studies of SERMs in the treatment of idiopathic male factor infertility are limited and heterogenous,preventing this meta-analysis from investigating the efficacy of SERMs on male infertility.The effect of clomiphene citrate or tamoxifen on the pregnancy rate remains uncertain.
基金supported by the National Natural Science Foundation of China(42177341)the Natural Science Basic Research Program of Shanxi,China(202203021222138).
文摘Organic material combined with inorganic fertilizer has been shown to greatly improve crop yield and maintain soil fertility globally. However, it remains unclear if crop yield and soil fertility can be sustained in the long term under the combined application of organic and inorganic fertilizers. Three long-term field trials were conducted to investigate the effects of organic amendments on the grain sustainable yield index(SYI), soil fertility index(SFI)and nutrient balance in maize–wheat cropping systems of central and southern China during 1991–2019. Five treatments were included in the trials: 1) no fertilization(control);2) balanced mineral fertilization(NPK);3) NPK plus manure(NPKM);4) high dose of NPK plus manure(1.5NPKM);and 5) NPK plus crop straw(NPKS). Over time, the grain yields of wheat and maize showed an increasing trend in all four fertilization treatments at the Yangling(YL) and Zhengzhou(ZZ) locations, while they declined at Qiyang(QY). The grain yield in the NPKM and 1.5NPKM treatments gradually exceeded that of the NPK and NPKS treatments at the QY site. The largest SYI was recorded in the NPKM treatment across the three sites, suggesting that inorganic fertilizer combined with manure can effectively improve crop yield sustainability. Higher SYI values were recorded at the YL and ZZ sites than at the QY site, possibly because the soil was more acid at QY. The key factors affecting grain yield were soil available phosphorus(AP) and available potassium(AK) at the YL and ZZ sites, and pH and AP at the QY site.All fertilization treatments resulted in soil N and P surpluses at the three sites, but soil K surpluses were recorded only at the QY site. The SFI was greater in the 1.5NPKM, NPKM and NPKS treatments than in the NPK treatment by 13.3–40.0 and 16.4–63.6% at the YL and ZZ sites, respectively, and was significantly higher in the NPKM and 1.5NPKM treatments than in the NPK and NPKS treatments at the QY site. A significant, positive linear relationship was found between SFI and crop yield, and SYI and nutrient balance, indicating that grain yield and its sustainability significantly increased with increasing soil fertility. The apparent N, P and K balances positively affected SFI.This study suggests that the appropriate amount of manure mixed with mineral NPK fertilizer is beneficial to the development of sustainable agriculture, which effectively increases the crop yield and yield sustainability by improving soil fertility.
基金supported by research grants from the Natural Science Foundation of Shandong Province,China(ZR2020MC092)the Key Research and Development Project of Shandong Province,China(2019TSCYCX-33)the Key Research and Development Project of Shandong Province,China(LJNY202025).
文摘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.
基金supported by the Shenyang Municipal Science and Technology Project,China(23-409-2-03)the Liaoning Provincial Department of Science and Technology Project,China(Z20230183)the Liaoning Provincial Applied Basic Research Program,China(2022JH2/101300173).
文摘Both soil organic carbon (SOC) and iron (Fe) oxide content, among other factors, drive the formation and stability of soil aggregates.However, the mechanism of these drivers in greenhouse soil fertilized with organic fertilizer is not well understood.In a 3-year field experiment, we aimed to investigate the factors which drive the stability of soil aggregates in greenhouse soil.To explore the impact of organic fertilizer on soil aggregates, we established four treatments:no fertilization (CK);inorganic fertilizer (CF);organic fertilizer (OF);and combined application of inorganic and organic fertilizers(COF).The application of organic fertilizer significantly enhanced the stability of aggregates, that is it enhanced the mean weight diameter, geometric mean diameter and aggregate content (%) of>0.25 mm aggregate fractions.OF and COF treatments increased the concentration of SOC, especially the aliphatic-C, aromatic-C and polysaccharide-C components of SOC, particularly in>0.25 mm aggregates.Organic fertilizer application significantly increased the content of free Fe(Fed), reactive Fe (Feo), and non-crystalline Fe in both bulk soil and aggregates.Furthermore, non-crystalline Fe showed a positive correlation with SOC content in both bulk soil and aggregates.Both non-crystalline Fe and SOC were significantly positively correlated with>2 mm mean weight diameter.Overall, we believe that the increase of SOC, aromatic-C, and non-crystal ine Fe concentrations in soil after the application of organic fertilizer is the reason for improving soil aggregate stability.
基金funded by the Science and Technology Innovation Programof Jiangsu Province,China for“Carbon Dioxide Emission Peaking and Carbon Neutrality”(BE2022307).
文摘To promote the growth of cutting seeding of poplar(Populus L.),nitrogen(N)fertilizer and surface weed managements were required.We here conducted a pot experiment to examine the effects of natural vegetation,barnyardgrass(Echinochloa Beauv.),and sesbania(Sesbania cannabina pers.)on the growth of poplar cutting seedlings,soil properties,and ammonia(NH3)volatilization under three N inputs(0,0.5,and 1.5 g/pot,i.e.,N0,N0.5,and N1,respectively).Results showed that N application promoted the growth of poplar cutting seedlings,including plant height,ground diameter,and biomass,compared with N0 treatment.Moreover,under N0,sesbania significantly increased the plant height by 87.1%,barnyardgrass and sesbania significantly increased the ground diameter(16.2%and 51.5%),and biomass(67.4%and 74.7%)of poplar cutting seedlings,compared with natural vegetation management.Compared to natural vegetation,soil organic matter(SOM)of barnyardgrass and sesbania covered soil significantly increased by 12.4%and 18.7%at N1,respectively.In addition,soil total N(TN)content was significantly increased by 15.8%in barnyardgrass planted at N0.The soil ammonium N(NH_(4)^(+)-N)content decreased with the planting of barnyardgrass and sesbania across all levels of N application.At N0.5,the nitrate N(NO_(3)^(−)-N)content of soil planted with barnyardgrass significantly increased compared to both the natural vegetation and the sesbania groups.Compared to the natural vegetation,the soil available phosphorus(AP)content of the barnyardgrass group significantly increasing by 78.8%at N0.5,soil available potassium(AK)content was significantly reduced by 12.5%in the sesbania group at N0 and increased by 24.1%in the barnyardgrass group at N1.We found that cumulative NH3 emissions were significantly higher in all treatment groups at the N1 level than that at the N0.5 level,while the differences among the three plants treated were not significant.The results suggest that both barnyardgrass and sesbania promote seedling growth in the short term,while also increase certain properties.Therefore,effective herb management during the seedling stage is recommended in nurseries to support seedling growth and retain soil fertility.
基金supported by the National Key Research and Development Program of China(2022YFD190160304 and 2018YFD0301206)Natural Science Foundation of Sichuan Province(2022NSFSC0013)Sichuan Provincial Maize Innovation Team Construction Project(SCCXTD-2023-02).
文摘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.
基金supported by the National Natural Science Foundation of China(No.52170138)the National Key Research and Development Program of China(No.2023YFD1900305)+3 种基金Qingdao Agricultural University Doctoral Start-Up Fund(No.6631122003)the Project of Talent IntroductionEducation Program of Youth Innovation Teams in Universities of Shandong Province(2021–05)Shandong Provincial College Youth Innovation Team Program(No.2023KJ169).
文摘Cyclosporin A fermentation residue(CFR)is a type of organic waste generated during the production of cyclosporin A,which are abundant in nutrients including organic matter,phosphorus,nitrogen and potassium.Inappropriate handling of CFR not only waste valuable bioresources,but may also lead to the cyclosporin A and associated resistance genes into the natural environment,posing a significant threat to ecological system and human health.Land application was an effective way to resource recovery of CFR after aerobic composting(CAC).This study investigated the impact of CAC on soil fertility and environmental safety.The results indicated that CAC could improve soil nutrient contents and enhance enzyme activities.CAC altered the diversity and community composition of soil bacteria,resulting in an increase in the abundance of relevant bacteria beneficial for organic matter decomposition and cyclosporin A degradation.The introduced cyclosporin A(71.69μg/kg)completely degraded within 20 days due to soil biodegradation.The significantly increased abundance of intIl,mdr3,pgp,TSR and pmra in the soil cultivation early stage were restored to the soil background level within 90 days,indicating a reduced risk of antimicrobial resistance.The results demonstrated that reasonable land application of CAC could improve soil fertility without antimicrobial resistance risk,which is helpful for evaluating the resource utilization value and environmental risks of antibiotic fermentation residue after aerobic composting.
基金supported by the State Key Laboratory of Arid Land Crop Science, Gansu Agricultural University,China (GSCS-2022-Z02)the National Key R&D Program of China (2022YFD1900300)+2 种基金the National Natural Science Foundation of China (32260549)the Innovation Group of Basic Research in Gansu Province, China (25JRRA807)the Major Special Research Projects in Gansu Province, China (22ZD6NA009)。
文摘The application of organic fertilizers has become an increasingly popular practice in maize production to reduce thegaseous nitrogen(N) loss and soil degradation caused by inorganic fertilizers. Organic fertilizer plays a key rolein improving soil quality and stabilizing maize yields, but few studies have compared different substitution rates. Afield study was carried out in 2021 and 2022, based on a long-term trial initiated in 2016, which included five organicfertilizer N substitution rates with equal inputs of 200 kg N ha^(–1): 0% organic fertilizer(T1, 100% inorganic fertilizer),50.0% organic+50.0% inorganic fertilizer(T2), 37.5% organic+62.5% inorganic fertilizer(T3), 25.0% organic+75.0%inorganic fertilizer(T4), and 12.5% organic+87.5% inorganic fertilizer(T5), as well as a no fertilizer control(T6). Theresults of the two years showed that T3 and T1 had the highest grain yield and biomass, respectively, and there wasno significant difference between T1 and T3. Compared with T1, the 12.5, 25.0, 37.5, and 50.0% substitution rates in T5, T4, T3, and T2 significantly reduced total nitrogen losses(NH_(3), N_(2)O) by 8.3, 16.1, 18.7, and 27.0%, respectively.Nitrogen use efficiency(NUE) was higher in T5, T3, and T1, and there were no significant differences among them.Organic fertilizer substitution directly reduced NH_(3)volatilization and N_(2)O emission from farmland by lowering theammonium nitrogen and alkali-dissolved N contents and by increasing soil moisture. These substitution treatmentsreduced N_(2)O emissions indirectly by regulating the abundances of AOB and nirK-harboring genes by promotingsoil moisture. Specifically, the 37.5% organic fertilizer substitution reduces NH_(3)volatilization and N_(2)O emission from farmland by reducing the ammonium nitrogen and alkali-dissolved N contents and increasing moisture, which negatively regulate the abundance of AOB and nir K-harboring genes to reduce N_(2)O emissions indirectly in rainfed maize fields on the Loess Plateau of China.
