Synergistic effects of planting density and nitrogen fertilization on chlorophyll degradation and leaf senescence after silking in maize

Regulating planting density and nitrogen(N)fertilization could delay chlorophyll(Chl)degradation and leaf senescence in maize cultivars.This study measured changes in ear leaf green area(GLA_(ear)),Chl content,the activities of Chl a-degrading enzymes after silking,and the post-silking dry matter accumulation and grain yield under multiple planting densities and N fertilization rates.The dynamic change of GLA_(ear)after silking fitted to the logistic model,and the GLA_(ear) duration and the GLAearat 42 d after silking were affected mainly by the duration of the initial senescence period(T_(1))which was a key factor of the leaf senescence.The average chlorophyllase(CLH)activity was 8.3 times higher than pheophytinase activity and contributed most to the Chl content,indicating that CLH is a key enzyme for degrading Chl a in maize.Increasing density increased the CLH activity and decreased the Chl content,T1,GLAear,and GLA_(ear) duration.Under high density,appropriate N application reduced CLH activity,increased Chl content,prolonged T1,alleviated high-density-induced leaf senescence,and increased post-silking dry matter accumulation and grain yield.

Simulation of the Ecosystem Productivity Responses to Aerosol Diffuse Radiation Fertilization Effects over the Pan-Arctic during 2001–19

The pan-Arctic is confronted with air pollution transported from lower latitudes.Observations have shown that aerosols help increase plant photosynthesis through the diffuse radiation fertilization effects(DRFEs).While such DRFEs have been explored at low to middle latitudes,the aerosol impacts on pan-Arctic ecosystems and the contributions by anthropogenic and natural emission sources remain less quantified.Here,we perform regional simulations at 0.2o×0.2ousing a well-validated vegetation model(Yale Interactive terrestrial Biosphere,YIBs)in combination with multi-source of observations to quantify the impacts of aerosol DRFEs on the net primary productivity(NPP)in the pan-Arctic during 2001-19.Results show that aerosol DRFEs increase pan-Arctic NPP by 2.19 Pg C(12.8%)yr^(-1)under clear-sky conditions,in which natural and anthropogenic sources contribute to 8.9% and 3.9%,respectively.Under all-sky conditions,such DRFEs are largely dampened by cloud to only 0.26 Pg C(1.24%)yr^(-1),with contributions of 0.65% by natural and 0.59% by anthropogenic species.Natural aerosols cause a positive NPP trend of 0.022% yr^(-1)following the increased fire activities in the pan-Arctic.In contrast,anthropogenic aerosols induce a negative trend of-0.01% yr^(-1)due to reduced emissions from the middle latitudes.Such trends in aerosol DRFEs show a turning point in the year of 2007 with more positive NPP trends by natural aerosols but negative NPP trends by anthropogenic aerosols thereafter.Though affected by modeling uncertainties,this study suggests a likely increasing impact of aerosols on terrestrial ecosystems in the pan-Arctic under global warming.

Research Progress of Different Fertilization Models in Farmland Based on Bibliometrics

In order to grasp the research status of different fertilization modes in China s farmland more comprehensively, with papers in core journals of Chinese Peking University collected in CNKI database from 2003 to 2022 as the main research object, this paper analyzed the research status of different fertilization modes from the perspectives of annual number of published papers, published journals, keywords and highly cited papers applying the bibliometrics research method. This study provides reference for the research in this field.

Persistence of fertilization effects on soil organic carbon in degraded alpine wetlands in the Yellow River source region

In the restoration of degraded wetlands,fertilization can improve the vegetation-soil-microorganisms complex,thereby affecting the organic carbon content.However,it is currently unclear whether these effects are sustainable.This study employed Biolog-Eco surveys to investigate the changes in vegetation characteristics,soil physicochemical properties,and soil microbial functional diversity in degraded alpine wetlands of the source region of the Yellow River at 3 and 15 months after the application of nitrogen,phosphorus,and organic mixed fertilizer.The following results were obtained:The addition of nitrogen fertilizer and organic compost significantly affects the soil organic carbon content in degraded wetlands.Three months after fertilization,nitrogen addition increases soil organic carbon in both lightly and severely degraded wetlands,whereas after 15 months,organic compost enhanced the soil organic carbon level in severely degraded wetlands.Structural equation modeling indicates that fertilization decreases the soil pH and directly or indirectly influences the soil organic carbon levels through variations in the soil water content and the aboveground biomass of vegetation.Three months after fertilization,nitrogen fertilizer showed a direct positive effect on soil organic carbon.However,organic mixed fertilizer indirectly reduced soil organic carbon by increasing biomass and decreasing soil moisture.After 15 months,none of the fertilizers significantly affected the soil organic carbon level.In summary,it can be inferred that the addition of nitrogen fertilizer lacks sustainability in positively influencing the organic carbon content.

Calcium-Magnesium Ca/Mg Ratios and Their Agronomic Implications for the Optimization of Phosphate Fertilization in Rainfed Rice Farming on Acidic Ferralsol in the Forest Zone of Ivory Coast

This study is a contribution to improving rice productivity on acidic plateau soils of the tropical rainforest zone. It is based on taking into account the cationic balances of the soil in order to optimize the phosphorus (P) nutrition of rice on these acidic soils, where this nutrient constitutes a limiting factor for agricultural production. Three (3) pot trials were conducted in Adiopodoumé in the forested south of Côte d’Ivoire. The interactive effects of calcium carbonate (0, 25, 50 and 75 kg Ca ha−1) and magnesium sulfate (0, 25, 50 and 75 kg Mg ha−1) were evaluated on the response of NERICA 5 rice at doses 0, 25, 50 and 75 kg P ha−1 of natural phosphate from Togo, applied only once at the start of the experiment. Additional fertilizers of nitrogen (N) (100 kg N ha−1) and potassium (K) (50 kg KCl ha−1) were added to each of the tests in a split-plot device. The test results revealed a paddy production potential of approximately 3 to 5 t⋅ha−1 for NERICA 5 on an acidic soil, under the effect of the interaction of P, Ca and Mg. The quadratic response of rice yield to the doses of these fertilizers would be more dependent on their balance, itself influenced by Ca nutrition. For the sustainability and maintenance of rice production in agro-ecology studied, it was recommended doses of 38 kg Ca ha−1, 34 kg Mg ha−1 in a Ca/Mg ratio (1/1) with intakes of 41 kg P ha−1, overall in a ratio 1/1/1 (P/Ca/Mg) more favorable to the availability of free iron considered a guiding element of mineral nutrition. Thus, these promising results should be confirmed in a real environment for better management of the fertilization of rice cultivated on acidic plateau soils in Côte d’Ivoire.

Effects of Fertilization on Soil CO_(2) Efflux in Chinese Hickory(Carya cathayensis)Stands

Chinese hickory(Carya cathayensis Sarg.)is a popular nut tree in China,but there is little information about the influences of fertilization on soil CO_(2) efflux and soil microbial biomass.This study evaluated the short-term effects of different fertilizer applications on soil CO_(2) efflux and soil microbial biomass in Chinese hickory stands.Four fertilizer treatments were established:control(CK,no fertilizer),inorganic fertilizer(IF),organic fertilizer(OF),and equal parts organic and inorganic N fertilizers(OIF).A field experiment was conducted to measure soil CO_(2) effluxes using closed chamber and gas chromatography techniques.Regardless of the fertilization practices,soil CO_(2) effluxes of all the treatments showed a similar temporal pattern,with the highest value in summer and the lowest in winter.The mean annual soil CO_(2) efflux in the IF treatment was significantly higher than that in the CK,OIF,and OF treatments.There was no significant difference in soil CO_(2) efflux between the OIF,OF,and CK treatments.Soil CO_(2) effluxes were significantly affected by soil temperature.Soil dissolved organic carbon(DOC)was positively correlated with soil CO_(2) efflux only in the CK treatment.Regression analysis,including soil temperature,moisture,and DOC,showed that soil temperature was the primary factor influencing soil CO_(2) effluxes.Both OF and OIF treatments increased concentrations of soil microbial biomass carbon(MBC)and microbial biomass nitrogen(MBN),but decreased the ratio of MBC:MBN.These results reveal that applying organic fertilizer,either alone or combined with inorganic fertilizer,may be the optimal strategy for mitigating soil CO_(2) emission and improving soil quality in Chinese hickory stands.

Hole fertilization in the root zone facilitates maize yield and nitrogen utilization by mitigating potential N loss and improving mineral N accumulation

Reducing environmental impacts and improving N utilization are critical to ensuring food security in China.Although root-zone fertilization has been considered an effective strategy to improve nitrogen use efficiency (NUE),the effect of controlled-release urea (CRU) applied in conjunction with normal urea in this mode is unclear.Therefore,a 3-year field experiment was conducted using a no-N-added as a control and two fertilization modes (FF,furrow fertilization by manual trenching,i.e.,farmer fertilizer practice;HF:root-zone hole fertilization by point broadcast manually) at 210 kg N ha^(–1) (controlled-release:normal fertilizer=5:5),along with a 1-year in-situ microplot experiment.Maize yield,NUE and N loss were investigated under different fertilization modes.The results showed that compared with FF,HF improved the average yield and N recovery efficiency by 8.5 and 22.3%over three years,respectively.HF had a greater potential for application than FF treatment,which led to increases in dry matter accumulation,total N uptake,SPAD value and LAI.In addition,HF remarkably enhanced the accumulation of ^(15)N derived from fertilizer by 17.2%compared with FF,which in turn reduced the potential loss of^(15)N by 43.8%.HF increased the accumulation of N in the tillage layer of soils at harvest for potential use in the subsequent season relative to FF.Hence,HF could match the N requirement of summer maize,sustain yield,improve NUE and reduce environmental N loss simultaneously.Overall,root-zone hole fertilization with blended CRU and normal urea can represent an effective and promising practice to achieve environmental integrity and food security on the North China Plain,which deserves further application and investigation.

Evaluation of three sets of advanced backcrosses of eggplant with wild relatives from different gene pools under low N fertilization conditions

The development of new cultivars with improved nitrogen use efficiency(NUE)is key for implementing sustainable agriculture practices.Crop wild relatives(CWRs)provide valuable genetic resources for breeding programs aimed at achieving this goal.In this study,three eggplant(Solanum melongena)accessions together with their advanced backcrosses(ABs;BC3 to BC5 generations)were evaluated for 22 morpho-agronomic,physiological,and NUE traits under low nitrogen(LN)fertilization conditions.The ABs were developed with introgressions from the wild relatives Solanum insanum,Solanum dasyphyllum,and Solanum elaeagnifolium.The AB population comprised a total of 25,59,and 59 genotypes,respectively,with overall donor wild relative genome coverage percentages of 58.8%,46.3%,and 99.2%.The three S.melongena recurrent parents were also evaluated under control(normal)N fertilization.Reduction of N fertilization in the parents resulted in decreased chlorophyll content-related traits,aerial biomass,stem diameter,and yield and increased NUE,nitrogen uptake efficiency(NUpE),and nitrogen utilization efficiency(NUtE).However,the decrease in yield was moderate,ranging between 62.6%and 72.6%.A high phenotypic variation was observed within each of the three sets of ABs under LN conditions,with some individuals displaying improved transgressive characteristics over the recurrent parents.Using the single primer enrichment technology 5 k probes platform for high-throughput genotyping,we observed a variable but high degree of recurrent parent genome recovery in the ABs attributable to the lines recombination,allowing the successful identification of 16 quantitative trait loci(QTL).Different allelic effects were observed for the introgressed QTL alleles.Several candidate genes were identified in the QTL regions associated with plant growth,yield,fruit size,and NUE-related parameters.Our results show that eggplant materials with introgressions from CWRs can result in a dramatic impact in eggplant breeding for a more sustainable agriculture.

Repositioning fertilizer manufacturing subsidies for improving food security and reducing greenhouse gas emissions in China

China removed fertilizer manufacturing subsidies from 2015 to 2018 to bolster market-oriented reforms and foster environmentally sustainable practices.However,the impact of this policy reform on food security and the environment remains inadequately evaluated.Moreover,although green and low-carbon technologies offer environmental advantages,their widespread adoption is hindered by prohibitively high costs.This study analyzes the impact of removing fertilizer manufacturing subsidies and explores the potential feasibility of redirecting fertilizer manufacturing subsidies to invest in the diffusion of these technologies.Utilizing the China Agricultural University Agri-food Systems model,we analyzed the potential for achieving mutually beneficial outcomes regarding food security and environmental sustainability.The findings indicate that removing fertilizer manufacturing subsidies has reduced greenhouse gas(GHG)emissions from agricultural activities by 3.88 million metric tons,with minimal impact on food production.Redirecting fertilizer manufacturing subsidies to invest in green and low-carbon technologies,including slow and controlled-release fertilizer,organic-inorganic compound fertilizers,and machine deep placement of fertilizer,emerges as a strategy to concurrently curtail GHG emissions,ensure food security,and secure robust economic returns.Finally,we propose a comprehensive set of government interventions,including subsidies,field guidance,and improved extension systems,to promote the widespread adoption of these technologies.

Single and combined eff ects of fertilization,ectomycorrhizal inoculation,and drought on container-grown Japanese larch seedlings

Climate change can intensify drought in many regions of the world and lead to more frequent drought events or altered cycles of soil water status.Therefore,it is important to enhance the tolerance to drought and thus health,vigor,and success of transplantation seedlings used in the forestry by modifying fertilization and promoting mycorrhization.Here,we sowed seeds of Japanese larch(Larix kaempferi)in 0.2-L containers with 0.5 g(low fertilization;LF)or 2 g(high fertilization;HF)of slow-release fertilizer early in the growing season.One month later,we irrigated seedlings with non-sterilized ectomycorrhizal inoculum(ECM)or sterilized solution(non-ECM),and after about 2 months,plants were either kept well watered(WW;500 mL water/plant/week)or subjected to drought(DR;50 mL water per plant/week)until the end of the growing season.HF largely stimulated plant growth and above-and belowground biomass production,eff ects that are of practical signifi cance,but caused a small decrease in stomatal conductance(Gs 390)and transpiration rate(E 390),which in practice is insignifi cant.ECM treatment resulted in moderate inhibition of seedling growth and biomass and largely canceled out the enhancement of biomass and foliar K content by HF.DR caused a large decrease in CO 2 assimilation,and enhanced stomatal closure and induced senescence.DR also largely depleted foliar Mg and enriched foliar K.Although DR caused a large decrease in foliar P content in LF,it moderately increased P in HF.Likewise,DR increased foliar K in HF but not in LF,and decreased foliar P in ECM plants but not in non-ECM plants.Conversely,ECM plants exhibited a large enrichment in foliar P under WW and had a lower water potential under DR when grown in LF.These results indicate that the drought tolerance and health and vigor of Japanese larch seedlings can be modifi ed by soil fertility and soil microorganisms.This study provides a basis for new multifactorial research programs aimed at producing seedlings of superior quality for forestation under climate change.

RETRACTED:Effect of Long-Term Inorganic Fertilization on Diversity and Abundance of Bacterial and Archaeal Communities at Tillage in Irrigated Rice Field

Short Retraction Notice The paper does not meet the standards of "Advances in Bioscience and Biotechnology". This article has been retracted to straighten the academic record. In making this decision the Editorial Board follows COPE's Retraction Guidelines. The aim is to promote the circulation of scientific research by offering an ideal research publication platform with due consideration of internationally accepted standards on publication ethics. The Editorial Board would like to extend its sincere apologies for any inconvenience this retraction may have caused. Editor guiding this retraction: Prof. Abass Alavi (EiC of ABB). Please see the article page for more details. The full retraction notice in PDF is preceding the original paper which is marked "RETRACTED".

Mixing trait-based corn(Zea mays L.)cultivars increases yield through pollination synchronization and increased cross-fertilization

Abiotic stress such as high temperature at flowering is one of many conditions reducing yield of corn(Zea mays L.).Mixing corn cultivars with diverse functional traits increases within-crop diversity and provides a potential means of mitigating yield losses under stress conditions.We conducted a three-year field study to investigate the effects of cultivar mixtures on kernel setting rate,pollen sources,and yield.This study consisted of six treatments,including two high temperature-tolerant(HTT)monocrops of WK702 and DH701,two high temperature-sensitive(HTS)monocrops of DH605 and DH662,and two HTT–HTS mixtures of WK702-DH605 and DH701-DH662.The anthesis–silking interval(ASI)was 0.9–1.6 days shorter in mixtures than in monocrops.Kernel setting rate was increased in mixtures(86.4%–88.7%)compared with those in monocrops(74.7%–84.1%)as a result of synchrony and complementarity of pollination.Grain yields of the HTT–HTS mixtures increased by 13.3%–18.7%,equivalent to 1169 to1605 kg ha^(-1),in comparison with HTS corn monocrops.The results of SSR markers showed that crossfertilization percentage in corn cultivar mixtures ranged from 29.3%to 47.8%,partially explaining yield improvement.Land equivalent ratio(LER)was 1.12 for corn mixtures and the partial land equivalent ratio(e.g.,>0.5)showed the complementary benefits in corn mixtures.The results indicated that mixing corn cultivars with diverse flowering and drought-tolerance traits increased yields via pollination synchrony.

The barriers of joining in vitro fertilization programs among infertile couples in developing countries:A scoping review

Objective:To determine the barriers of joining in-vitro fertilization(IVF)programs among infertile couples in developing countries.Methods:This study assessed infertile couples and the barriers or associated factors resulting in delayed decision-making of joining IVF program by searching databases PubMed,ScienceDirect,EBSCO,ClinicalKey,and Cochrane Library from inception until December 31,2021.Additional search strategies were snowballing literature search and citation tracking.Results:Eleven articles were included in the scoping review.The cost was the greatest barrier of joining IVF program.Limited access and lack of assisted reproductive technology centers,few qualified infertility trained staff,insufficient government support,low priority in government policy,along with sociocultural factors,such as religion and false beliefs or myths were also majorly considered to be associated obstacles.Conclusions:The main barrier associated with IVF program among infertile couples in developing countries is the high cost of the IVF services.

Characterization and QTL identification in eggplant introgression lines under two N fertilization levels

Lowering nitrogen inputs is a major goal for sustainable agriculture.In the present study,a set of 10 Solanum melongena introgression lines(ILs)developed using Solanum incanum as the exotic donor parent were grown under two nitrogen fertilization doses supplied with the irrigation system:1)8.25 mmol·L-1NH4NO3,corresponding to the high nitrogen treatment(HN),and 2)no external nitrogen supply,corresponding to the low nitrogen treatment(LN).Twenty traits,including plant growth and yield parameters,fruit size and morphology,nitrogen and carbon content in leaf and fruit,and phenolics content in fruit,were evaluated.The aim was to select of potential materials for eggplant breeding under low N inputs,as well as to identify and locate putative QTLs associated with the traits evaluated.No significant differences were observed between the soil characteristics of the HN and LN treatments,except for nitrogen and iron content,which was slightly lower in the HN,probably as a consequence of higher nutrient removal from soil by plants in the latter group.Analysis of variance showed that lowering nitrogen inputs did not significantly affect the final yield,fruit morphology,size and phenolics content.Most agronomic traits were highly and positively correlated with each other under both treatments,as well as total phenolics with chlorogenic acid content.The assessment of the differences between each IL and the recipient parent resulted in the identification of 36 QTLs associated with most of the traits—12 were specific to the HN,17 specific to the LN,and 7 were stable across treatments.The introgressed fragment of S.incanum generally had a negative effect on the trait,except for QTLs for fruit dry matter,for fruit length on chromosome 10 under the HN,and for fruit pedicel length on chromosome 9 under the LN.The increase over AN-S-26 of the allele of S.incanum for the QTLs detected ranged between-73.98% and 26.03% in HN and-73.67%and 34.43% in LN.These findings provide useful tools for the utilization of S.incanum in eggplant breeding under lower nitrogen fertilization.

Live births from in vitro fertilization-embryo transfer following the administration of gonadotropin-releasing hormone agonist without gonadotropins:Two case reports

BACKGROUND The prevalence of female infertility between the ages of 25 and 44 is 3.5%to 16.7%in developed countries and 6.9%to 9.3%in developing countries.This means that infertility affects one in six couples and is recognized by the World Health Organization as the fifth most serious global disability.The International Committee for Monitoring Assisted Reproductive Technology reported that the global total of babies born as a result of assisted reproductive technology procedures and other advanced fertility treatments is more than 8 million.Advancements in controlled ovarian hyperstimulation procedures led to crucial accomplishments in human fertility treatments.The European Society for Human Reproduction and Embryology guideline on ovarian stimulation gave us valuable evidence-based recommendations to optimize ovarian stimulation in assisted reproductive technology.Conventional ovarian stimulation protocols for in vitro fertilization(IVF)–embryo transfer are based upon the administration of gonadotropins combined with gonadotropin-releasing hormone(GnRH)analogues,either GnRH agonists(GnRHa)or antagonists.The development of ovarian cysts requires the combination of GnRHa and gonadotropins for controlled ovarian hyperstimulation.However,in rare cases patients may develop an ovarian hyper response after administration of GnRHa alone.CASE SUMMARY Here,two case studies were conducted.In the first case,a 33-year-old female diagnosed with polycystic ovary syndrome presented for her first IVF cycle at our reproductive center.Fourteen days after triptorelin acetate was administrated(day 18 of her menstrual cycle),bilateral ovaries presented polycystic manifestations.The patient was given 5000 IU of human chorionic gonadotropin.Twenty-two oocytes were obtained,and eight embryos formed.Two blastospheres were transferred in the frozen-thawed embryo transfer cycle,and the patient was impregnated.In the second case,a 37-year-old woman presented to the reproductive center for her first donor IVF cycle.Fourteen days after GnRHa administration,the transvaginal ultrasound revealed six follicles measuring 17-26 mm in the bilateral ovaries.The patient was given 10000 IU of human chorionic gonadotropin.Three oocytes were obtained,and three embryos formed.Two high-grade embryos were transferred in the frozen-thawed embryo transfer cycle,and the patient was impregnated.CONCLUSION These two special cases provide valuable knowledge through our experience.We hypothesize that oocyte retrieval can be an alternative to cycle cancellation in these conditions.Considering the high progesterone level in most cases of this situation,we advocate freezing embryos after oocyte retrieval rather than fresh embryo transfer.

Manure substitution improves maize yield by promoting soil fertility and mediating the microbial community in lime concretion black soil

Synthetic nitrogen(N)fertilizer has made a great contribution to the improvement of soil fertility and productivity,but excessive application of synthetic N fertilizer may cause agroecosystem risks,such as soil acidification,groundwater contamination and biodiversity reduction.Meanwhile,organic substitution has received increasing attention for its ecologically and environmentally friendly and productivity benefits.However,the linkages between manure substitution,crop yield and the underlying microbial mechanisms remain uncertain.To bridge this gap,a three-year field experiment was conducted with five fertilization regimes:i)Control,non-fertilization;CF,conventional synthetic fertilizer application;CF_(1/2)M_(1/2),1/2 N input via synthetic fertilizer and 1/2 N input via manure;CF_(1/4)M_(3/4),1/4 N input synthetic fertilizer and 3/4 N input via manure;M,manure application.All fertilization treatments were designed to have equal N input.Our results showed that all manure substituted treatments achieved high soil fertility indexes(SFI)and productivities by increasing the soil organic carbon(SOC),total N(TN)and available phosphorus(AP)concentrations,and by altering the bacterial community diversity and composition compared with CF.SOC,AP,and the soil C:N ratio were mainly responsible for microbial community variations.The co-occurrence network revealed that SOC and AP had strong positive associations with Rhodospirillales and Burkholderiales,while TN and C:N ratio had positive and negative associations with Micromonosporaceae,respectively.These specific taxa are implicated in soil macroelement turnover.Random Forest analysis predicted that both biotic(bacterial composition and Micromonosporaceae)and abiotic(AP,SOC,SFI,and TN)factors had significant effects on crop yield.The present work strengthens our understanding of the effects of manure substitution on crop yield and provides theoretical support for optimizing fertilization strategies.

Combined application of organic fertilizer and chemical fertilizer alleviates the kernel position effect in summer maize by promoting post-silking nitrogen uptake and dry matter accumulation

Adjusting agronomic measures to alleviate the kernel position effect in maize is important for ensuring high yields.In order to clarify whether the combined application of organic fertilizer and chemical fertilizer(CAOFCF)can alleviate the kernel position effect of summer maize,field experiments were conducted during the 2019 and 2020 growing seasons,and five treatments were assessed:CF,100%chemical fertilizer;OFCF1,15%organic fertilizer+85%chemical fertilizer;OFCF2,30%organic fertilizer+70%chemical fertilizer;OFCF3,45%organic fertilizer+55%chemical fertilizer;and OFCF4,60%organic fertilizer+40%chemical fertilizer.Compared with the CF treatment,the OFCF1 and OFCF2 treatments significantly alleviated the kernel position effect by increasing the weight ratio of inferior kernels to superior kernels and reducing the weight gap between the superior and inferior kernels.These effects were largely due to the improved filling and starch accumulation of inferior kernels.However,there were no obvious differences in the kernel position effect among plants treated with CF,OFCF3,or OFCF4 in most cases.Leaf area indexes,post-silking photosynthetic rates,and net assimilation rates were higher in plants treated with OFCF1 or OFCF2 than in those treated with CF,reflecting an enhanced photosynthetic capacity and improved postsilking dry matter accumulation(DMA)in the plants treated with OFCF1 or OFCF2.Compared with the CF treatment,the OFCF1 and OFCF2 treatments increased post-silking N uptake by 66.3 and 75.5%,respectively,which was the major factor driving post-silking photosynthetic capacity and DMA.Moreover,the increases in root DMA and zeatin riboside content observed following the OFCF1 and OFCF2 treatments resulted in reduced root senescence,which is associated with an increased post-silking N uptake.Analyses showed that post-silking N uptake,DMA,and grain yield in summer maize were negatively correlated with the kernel position effect.In conclusion,the combined application of 15-30%organic fertilizer and 70-85%chemical fertilizer alleviated the kernel position effect in summer maize by improving post-silking N uptake and DMA.These results provide new insights into how CAOFCF can be used to improve maize productivity.

Production traits and fertility of reciprocal hybrids between Argopecten irradians irradians and A.i.concentricus

The two bay scallop subspecies,Argopecten irradians irradians(NN)and A.i.concentricus(SS),are fast growing and major cultured bivalves in China.However,their relatively small sizes and decreasing production traits caused by long-term inbreeding have been major concerns to the industry in the last two decades.Hybridization between the two bay scallop subspecies may provide a new approach to breed a new variety with superior production traits for the industry.For this end,in this study,we hybridized the two bay scallop subspecies in order to obtain a new strain that incorporates the genes of both subspecies.No significant difference was found in fertilization rate,hatching rate and metamorphosis rate between the purebred and crossbred cohorts(NN♀×SS♂,denoted as NS;SS♀×NN♂,denoted as SN).Both mating strategy(intra-vs.inter-population crosses)and egg origin had significant effects on growth and survival at the larval stage.Heterosis was observed in the crossbred and was more pronounced in older stages.Genetic diversity of the reciprocal hybrids,especially that of SN,was increased compared with the purebred cohorts.Almost all hybrids were completely fertile and able to reproduce by selffertilization or by backcrossing with either parent.Apparently,male sterile individuals whose gonads were fully occupied by the ovary part at mature stage were found in the hybrids for the first time.The hybrids,especially SN,may provide precious germplasm resources for the production of ternary hybrids with the Peruvian scallop,A.purpuratus.

Coupling of reduced inorganic fertilizer with plant-based organic fertilizer as a promising fertilizer management strategy for colored rice in tropical regions

Colored rice is a type of high-quality,high-added-value rice that has attracted increasing attention in recent years.The use of large amounts of inorganic nitrogen fertilizer in rice fields results in low fertilizer use efficiency and high environmental pollution.Organic fertilizer is a promising way to improve soil quality and sustain high yields.However,most studies focus on the effect of animal-based organic fertilizers.The effects of different ratios of plantbased organic fertilizer and inorganic fertilizer on the grain yield and quality of colored rice have rarely been reported.Therefore,a two-year field experiment was conducted in 2020 and 2021 to study the effects of replacing inorganic N fertilizers with plant-based organic fertilizers on the yield,nitrogen use efficiency(NUE),and anthocyanin content of two colored rice varieties in a tropical region in China.The experimental treatments included no nitrogen fertilization(T1),100% inorganic nitrogen fertilizer(T2),30%inorganic nitrogen fertilizer substitution with plant-based organic fertilizer(T3),60%inorganic nitrogen fertilizer substitution with plant-based organic fertilizer(T4),and 100% plantbased organic fertilizer(T5).The total nitrogen provided to all the treatments except T1 was the same at 120 kg ha-1.Our results showed that the T3 treatment enhanced the grain yield and anthocyanin content of colored rice by increasing nitrogen use efficiency compared with T2.On average,grain yields were increased by 9 and 8%,while the anthocyanin content increased by 16 and 10% in the two colored rice varieties under T3 across the two years,respectively,as compared with T2.Further study of the residual effect of partial substitution of inorganic fertilizers showed that the substitution of inorganic fertilizer with plant-based organic fertilizer improved the soil physiochemical properties,and thus increased the rice grain yield,in the subsequent seasons.The highest grain yield of the subsequent rice crop was observed under the T5 treatment.Our results suggested that the application of plantbased organic fertilizers can sustain the production of colored rice with high anthocyanin content in tropical regions,which is beneficial in reconciling the relationship between rice production and environmental protection.

Subsequent pregnancy outcomes and fertility rates in the case series that underwent bilateral hypogastric artery ligation(BHGAL)due to severe postpartum hemorrhage

Objective:To evaluate the effect of bilateral hypogastric artery ligation(BHGAL)on women's pregnancy outcomes and fertility rates in cases with severe postpartum hemorrhage.Methods:Patients hospitalized in a tertiary care center between 2007 and 2018 were included in the study.The records of cases were obtained from the hospital database,retrospectively.Maternal demographic data,morbidities or complications associated with BHGAL surgery,any additional haemostatic interventional or surgical procedures,preoperative admission and lowest postoperative haematocrit-hemoglobin values,blood products given,type of anaesthesia,intensive care unit(ICU)and length of hospital stay were recorded.In cases without surgical sterilization,future fertility and subsequent pregnancy outcomes were assessed for at least two years after operation.Information was obtained through face-to-face or telephone interviews with patients whose long-term fertility and subsequent pregnancy outcomes were assessed.Results:Sixty-eight patients with BHGAL surgery history were included in the study.26 Of 37 cases(70%)that did not undergo surgical sterilization had a desire for pregnancy after the surgery.Six of these cases(23%)were diagnosed with secondary infertility.The fertility rate of these cases was 77%,and subsequent pregnancy was detected in 20 women.A total of 25 pregnancies,including first and second pregnancies,developed,and 15 of these pregnancies resulted in term delivery,six preterm births,one stillbirth,and three abortions.Conclusions:The postoperative pregnancy rate was found to be higher than the rate of women with infertility problems,and this surgery does not seem to adversely affect pregnancy outcomes.This is a tertiary center experience and cohort studies with large patient series are needed.