Effects of long-term partial substitution of inorganic fertilizer with pig manure and/or straw on nitrogen fractions and microbiological properties in greenhouse vegetable soils

Partial substitution of inorganic fertilizers with organic amendments is an important agricultural management practice.An 11-year field experiment(22 cropping periods)was carried out to analyze the impacts of different partial substitution treatments on crop yields and the transformation of nitrogen fractions in greenhouse vegetable soil.Four treatments with equal N,P_(2)O_(5),and K_(2)O inputs were selected,including complete inorganic fertilizer N(CN),50%inorganic fertilizer N plus 50%pig manure N(CPN),50%inorganic fertilizer N plus 25%pig manure N and 25%corn straw N(CPSN),and 50%inorganic fertilizer N plus 50%corn straw N(CSN).Organic substitution treatments tended to increase crop yields since the 6th cropping period compared to the CN treatment.From the 8th to the 22nd cropping periods,the highest yields were observed in the CPSN treatment where yields were 7.5-11.1%greater than in CN treatment.After 11-year fertilization,compared to CN,organic substitution treatments significantly increased the concentrations of NO_(3)^(-)-N,NH_(4)^(+)-N,acid hydrolysis ammonium-N(AHAN),amino acid-N(AAN),amino sugar-N(ASN),and acid hydrolysis unknown-N(AHUN)in soil by 45.0-69.4,32.8-58.1,49.3-66.6,62.0-69.5,34.5-100.3,and 109.2-172.9%,respectively.Redundancy analysis indicated that soil C/N and OC concentration significantly affected the distribution of N fractions.The highest concentrations of NO_(3)^(-)-N,AHAN,AAN,AHUN were found in the CPSN treatment.Organic substitution treatments increased the activities ofβ-glucosidase,β-cellobiosidase,N-acetyl-glucosamidase,L-aminopeptidase,and phosphatase in the soil.Organic substitution treatments reduced vector length and increased vector angle,indicating alleviation of constraints of C and N on soil microorganisms.Organic substitution treatments increased the total concentrations of phospholipid fatty acids(PLFAs)in the soil by 109.9-205.3%,and increased the relative abundance of G^(+)bacteria and fungi taxa,but decreased the relative abundance of G-bacteria,total bacteria,and actinomycetes.Overall,long-term organic substitution management increased soil OC concentration,C/N,and the microbial population,the latter in turn positively influenced soil enzyme activity.Enhanced microorganism numbers and enzyme activity enhanced soil N sequestration by transforming inorganic N to acid hydrolysis-N(AHN),and enhanced soil N supply capacity by activating non-acid hydrolysis-N(NAHN)to AHN,thus improving vegetable yield.Application of inorganic fertilizer,manure,and straw was a more effective fertilization model for achieving sustainable greenhouse vegetable production than application of inorganic fertilizer alone.

Spatial patterns and driving forces of urban vegetation greenness in China:A case study comprising 289 cities

Urban vegetation in China has changed substantially in recent decades due to rapid urbanization and dramatic climate change.Nevertheless,the spatial differentiation of greenness among major cities of China and its evolution process and drivers are still poorly understood.This study examined the spatial patterns of vegetation greenness across 289 cities in China in 2000,2005,2010,2015,and 2018 by using spatial autocorrelation analysis on the Normalized Difference Vegetation Index(NDVI);then,the influencing factors were analyzed by using the optimal parameters-based geographical detector(OPGD)model and 18 natural and anthropogenic indicators.The findings demonstrated a noticeable rise in the overall greenness of the selected cities during 2000-2018.The cities in northwest China and east China exhibited the rapidest and slowest greening,respectively,among the six sub-regions.A significant positive spatial correlation was detected between the greenness of the 289 cities in different periods,but the correlation strength weakened over time.The hot and very hot spots in southern and eastern China gradually shifted to the southwest.While the spatial pattern of urban greenness in China is primarily influenced by wind speed(WS)and precipitation(PRE),the interaction between PRE and gross domestic product(GDP)has the highest explanatory power.The explanatory power of most natural factors decreased and,conversely,the influence of anthropogenic factors generally increased.These findings emphasize the variations in the influence strength of multiple factors on urban greenness pattern,which should be taken into account to understand and adapt to the changing urban ecosystem.

Cosmetic or Dietary Vegetable Oils Sampled in the Cameroonian Market May Not Expose Consumers to Lipid Oxidation Products Generating Oxidative Stress and Inflammation

Vegetable oils are a source of energy, essential fatty acids, antioxidants and fat-soluble vitamins useful for human health care and development. These oils also contribute to organoleptic quality of their products’ derivatives. However, their chemical and physical properties can be modified by the mode of their extraction, storage and distribution. These modifications might negatively affect the nutritional quality of the oils. The goals of this study were to: sample different vegetable oils for cosmetic or dietary use marketed in Cameroon, and verify purity and oxidation states of each kind of oil through determination of its acidity, iodine, peroxide, saponification, refractive indexes and the conformity of the labeling. The carotene content, the level of polar components and specific absorbance were also determined. As the result, six oils namely palm, palm kernel, coconut, black cumin, peanut and shea butter were collected. Apart from labeling, chemicals and physicals parameters analyzed were generally in accordance with the Cameroonian and Codex Alimentarius standard. This study suggests that vegetable oils sampled in the Cameroonian market may not expose consumers to lipid oxidation products generating pathological oxidative stress and inflammation. However, efforts in application of existing standard need to be done as far as labeling are concerned.

Detection of Adenovirus in Fresh Fruit, Vegetables, Wastewater and Manure from Irrigated Farms in Ouagadougou, Burkina Faso

Enteric viral pathogens are responsible for numerous epidemics associated with the consumption of fresh fruit and vegetable, whether raw or minimally processed. The aim of the present study was to assess agricultural practices and the presence of adenovirus (AdV) in fruits and vegetables, manure and irrigation wastewater sampled in the urban and peri-urban perimeters of Ouagadougou. A total of 286 samples including 30 lettuces, 42 tomatoes, 30 carrots, 30 strawberries, 74 manures and 80 wastewater samples were collected from four market garden sites in and around Ouagadougou. Nested PCR was performed with specific primers to detect adenoviruses (AdVs). A face-to-face survey was carried out using a questionnaire on market garden production practices. Overall, adenoviruses prevalence was 5.9% [IC95, 3.2% - 8.7%] in all samples analyzed. It was specifically 7.14% (3/42) from tomatoes, 6.7% (2/30) from lettuces, 20% (6/30) on strawberries and 7.5% (6/80) in irrigation water. The survey showed that irrigation water came from untreated sources (dam, well, canal) and then 52% of farms used untreated manure. No farms have implemented measures to limit access by domestic and wild animals. This work shows the presence of human adenoviruses in surface irrigation water and fresh produce, which is of concern when fresh produce is consumed raw. To reduce the public health risks associated with consuming these foods, it is essential to follow good hygiene and cultivation practices.

Determination of Coumoxystrobin Residue in Vegetables by QeEChERS-UPLC-MS/MS

[Objectives]This study was conducted to establish a method for determining residual coumoxystrobin in vegetables using QeEChERS-liquid chromatography-tandem mass spectrometry(QeEChERS-LC-MS/MS).[Methods]The sample was extracted by acetonitrile,and the extract was purified by QeEChERS,concentrated by nitrogen blowing,and then detected.[Results]Coumoxystrobin had a good linear relation in the range of 0.01-10.0 mg/kg,and the linear equation was y=4686.92×x+5683.28,R^(2)=0.999.The limit of detection was 0.001 mg/kg,and the limit of quantitation was 0.003 mg/kg.[Conclusions]The method has the advantages of convenient and fast operation and stable detection process,and can provide technical support for the supervision and monitoring of coumoxystrobin.

A review:Health benefits and physicochemical characteristics of blended vegetable oils

Oil blending is the method of choice used worldwide to improve oxidative stability and nutritional value.There is no such edible oil/fat that meets all the recommendations from the health point of view.The fatty acid composition of vegetable oils decides the fate of the oil.Pure single oil is unable to provide a balanced amount of fatty acids(FAs)required/recommended on a daily intake basis.Blending oils/fats is an appropriate procedure of physically mixing multiple oils in suitable proportions which may provide functional lipids with improved antioxidant potential and desirable physical and chemical properties.This review piled up the accessible data on the blending of diverse oils/fats in the combination of binary,ternary,quaternary,or other types of oils into a single blended oil.Blending can be found very convincing towards appropriate FA profile,enhancement in physicochemical characteristics,and augmented stability for the period of storage or when used as cooking/frying processes which could ultimately serve as an effectual dietary intervention towards the health protectiveness.

Optimizing Household Wastes (Rice, Vegetables, and Fruit) as an Environmentally Friendly Electricity Generator

The high consumption of electricity and issues related to fossil energy have triggered an increase in energy prices and the scarcity of fossil resources.Consequently,many researchers are seeking alternative energy sources.One potential technology,the Microbial Fuel Cell(MFC)based on rice,vegetable,and fruit wastes,can convert chemical energy into electrical energy.This study aims to determine the potency of rice,vegetable,and fruit waste assisted by Cu/Mg electrodes as a generator of electricity.The method used was a laboratory experiment,including the following steps:electrode preparation,waste sample preparation,incubation of the waste samples,construction of a reactor using rice,vegetable,and fruit waste as a source of electricity,and testing.The tests included measuring electrical conductivity,electric current,voltage,current density,and power density.Based on the test results,the maximum current and voltage values for the fruit waste samples were 5.53 V and 11.5 mA,respectively,with a current density of 2.300 mA/cm^(2) and a power density of 12.719 mW/cm^(2).The results indicate the potential for a future development.The next step in development involves determining the optimum conditions for utilizing of rice,vegetable,and fruit waste.The results of the electrical conductivity test on rice,vegetable,and fruit waste samples were 1.51,2.88,and 3.98 mS,respectively,with the highest electrical conductivity value found in the fruit waste sample.

Comprehensive Prevention and Control Technology of Vegetable Diseases and Pests in Shandong Province

An in-depth research and practice has been conducted on vegetable diseases and pests in Shandong Province,and the principles of comprehensive and ecological control of diseases and pests are put forward,including agricultural control measures such as crop rotation,field cleaning,fertilizer and water management,physical control measures such as catching and killing,trapping,blocking,photoelectric energy treatment,biological control measures such as the use of natural enemies,pathogenic microorganisms,other beneficial organisms and metabolites,and scientific and rational chemical control measures.Comprehensive prevention and control not only controls vegetable diseases and pests effectively,but also protects the ecological environment.

Different Foliar Fertilizer Treatments Affect the Yield and Quality of Brassica napus L.for Both Vegetable and Oil Dual-Use Rape

Field experiments were carried out to study the effect of different foliar fertilizer treatments on the agronomic traits,yield,and quality of Brassica napus L.for both vegetable and oil dual-use rape.The seedlings of‘Youtai 929’,‘Jinyoutai 1’,and‘Zhongshuang 11’were sprayed with potassium dihydrogen phosphate,naphthylacetic acid,and selenium fertilizer,and the agronomic traits,yield,and quality were determined.The results showed that the naphthylacetic acid treatment had the highest indexes before winter,followed by the selenium fertilizer treatment.At the harvesting stage,the plant height,number of siliquae,yield per plant,and number of effective branches on the main stem of the three varieties were the highest in the naphthylacetic acid treatment,followed by those in the potassium dihydrogen phosphate treatment.The fresh shoot quality was the best in the selenium fertilizer treatment and the second in the naphthylacetic acid treatment.‘Jinyoutai 1’applied with naphthylacetic acid had the highest economic benefit of 4971.78 CNY/667m^(2),which was 642.32 CNY/667m^(2) higher than that of the control.The findings suggested that naphthylacetic acid was suitable to be used as the foliar fertilizer for the seedlings of B.napus varieties for both vegetable and oilseed,and the additional application of selenium fertilizer demonstrated better effect.

Drivers,Trends,and Patterns of Changing Vegetation-greenness in Nansha Islands,China from 2016 to 2022

Changes in vegetation status generally also represents changes in the ecological health of islands and reefs(IRs).However,studies are limited of drivers and trends of vegetation change of Nansha Islands,China and how they relate to climate change and human activities.To resolve this limitation,we studied changes to the Normalized Difference Vegetation Index(NDVI)vegetation-greenness index for 22 IRs of Nansha Islands during normal and extreme conditions.Trends of vegetation greenness were analyzed using Sen's slope and Mann-Kendall test at two spatial scales(pixel and island),and driving factor analyses were performed by time-lagged partial correlation analyses.These were related to impacts from human activities and climatic factors under normal(temperature,precipitation,radiation,and Normalized Difference Built-up Index(NDBI))and extreme conditions(wind speed and latitude of IRs)from 2016 to 2022.Results showed:1)among the 22 IRs,NDVI increased/decreased significantly in 15/4 IRs,respectively.Huayang Reef had the highest NDVI change-rate(0.48%/mon),and Zhongye Island had the lowest(–0.29%/mon).Local spatial patterns were in one of two forms:dotted-form,and degradation in banded-form.2)Under normal conditions,human activities(characterized by NDBI)had higher impacts on vegetation-greenness than other factors.3)Under extreme conditions,wind speed(R^(2)=0.2337,P<0.05)and latitude(R^(2)=0.2769,P<0.05)provided limited explanation for changes from typhoon events.Our results provide scientific support for the sustainable development of Nansha Islands and the United Nations‘Ocean Decade’initiative.

Adoption of Solar Pumping Systems by Vegetable Farmers in Niayes Agro-Ecological Zone of Senegal: Adoption as a Sequential Process

This article examines the determinants of the adoption of solar pumping systems (PV) by vegetable farmers in the Niayes area of Senegal. To measure the determinants, we used a sequential logit model to translate the adoption process from becoming aware of solar pumping systems to testing them, i.e. using them at least once, and then continuing to use them over time. The results show that the main variables affecting awareness of the use of solar pumping systems (PV) are age, marital status, experience, access to credit, the farmer’s knowledge of climate change, the farmer’s origin in the Thiès region and length of time in the Niayes area. The first use of PVs is influenced by factors such as the size of the plot, the distance of the plot from the main road or from the market. Finally, the decision to adopt or continue use is influenced by gender, experience, household size and access to credit. Surprisingly, access to credit does not affect the first use of solar pumping systems, but plays a key role in their continued use.

Farmers’ Knowledge and Awareness towards the Use of Agrochemicals in Vegetable Cultivation, Fako Cameroon

Agrochemicals are contemporary, omnipresent tool used in vegetable cultivation. Farmers’ knowledge and awareness of the proper usage of agrochemicals are critical for mitigating the negative effects on human health. This cross-sectional study was aimed at assessing the usage knowledge, risk awareness of toxicological and chemical classes, proper handling and use practices for agrochemicals homologated for use in vegetable farming, and the occurrence of health-related symptoms as a result of exposure among these farmers. The study included 93 vegetable growers from agricultural hotspot towns in Fako, southwest Cameroon. The field study, ran from November 2021 to December 2023, using a questionnaire to collect information on farmers demographic, and their knowledge of pesticide classes, and the related risk of associated with the handling of agrochemicals. Results show that all vegetable farmers, particularly those engaged in agribusiness, employ pesticide inputs to maximize production. Six pesticides, two fertilizer types, and one unknown substance were identified. While 23 active compounds were found, the most utilized were abamectin, emamectin (10.46%), dimethoate (9.30%,) and ethoprophos (8.13%). Two active chemicals, dimethoate and methalaxyl, are illegal yet remain in circulation. Toxicological classes I and II, with the greatest harmful effect on human health, were the most commonly utilized (64.27%). Thirty-nine percent of farmers never use personal protection equipment when working with agrochemicals, demonstrating a significant gap in knowledge and awareness of agrochemicals and their various applications and handling procedures in the field. The government should implement an intensive specialized educational program for on-field farmers with incentives in order to promote sustainable agriculture methods that ensure environmental and human safety.

Development status and prospect of cold chain logistics of fruits,vegetables,and agricultural products based on intelligent technology

The cold chain in the production area of fruits and vegetables is the primary link to reduce product loss and improve product quality,but it is also a weak link.With the application of big data technology in cold chain logistics,intelligent devices,and technologies have become important carriers for improving the efficiency of cold chain logistics in fruit and vegetable production areas,extending the shelf life of fruits and vegetables,and reducing fruit and vegetable losses.They have many advantages in fruit and vegetable pre-cooling,sorting and packaging,testing,warehousing,transportation,and other aspects.This article summarizes the rapidly developing and widely used intelligent technologies at home and abroad in recent years,including automated guided vehicle intelligent handling based on electromagnetic or optical technology,intelligent sorting based on sensors,electronic optics,and other technologies,intelligent detection based on computer vision technology,intelligent transportation based on perspective imaging technology,etc.It analyses and studies the innovative research and achievements of various scholars in applying intelligent technology in fruit and vegetable cold chain storage,sorting,detection,transportation,and other links,and improves the efficiency of fruit and vegetable cold chain logistics.However,applying intelligent technology in fruit and vegetable cold chain logistics also faces many problems.The challenges of high cost,difficulty in technological integration,and talent shortages have limited the development of intelligent technology in the field of fruit and vegetable cold chains.To solve the current problems,it is proposed that costs be controlled through independent research and development,technological innovation,and other means to lower the entry threshold for small enterprises.Strengthen integrating intelligent technology and cold chain logistics systems to improve data security and system compatibility.At the same time,the government should introduce relevant policies,provide necessary financial support,and establish talent training mechanisms.Accelerate the development and improvement of intelligent technology standards in the field of cold chain logistics.Through technological innovation,cost control,talent cultivation,and policy guidance,we aim to promote the upgrading of the agricultural industry and provide ideas for improving the quality and efficiency of fruit and vegetable cold chain logistics.

Strategies for High-quality Development of Greenhouse Vegetables in Zibo City,Shandong Province

This investigation report got a clear picture of the general situation of the development of greenhouse vegetable industry in Zibo,and found out the existing problems such as frequent harmful weather,few special varieties and high-grade varieties of greenhouse vegetables,fragmentation of new technology promotion of greenhouse vegetables,low level of intensive seedling raising of vegetables,backward level of facility planting structure and equipment,etc.This paper puts forward the strategies for the future high-quality development of vegetables:promoting the adjustment of vegetable planting structure,rationally arranging vegetables for rotation,strengthening vegetable technical guidance,and innovating vegetable consumption patterns.

Remediation Technologies for Cadmium Contamination in Greenhouse Vegetable Fields

Based on the literature and experimental results, three kinds of soil amendments, namely rice biochar, hydroxyapatite and potassium dihydrogen phosphate(KH2PO4), and deeper ploughing were selected to evaluate the field application effect of soil amendments and agronomic measures on the remediation of Cd contamination in greenhouse vegetable fields. Cd-contaminated greenhouse screening was conducted from 2015 to 2017. In September 2017, comparative tests of eight treatments were performed, and a preferred test was performed in September 2018. The screening results of the contaminated areas indicated that the distribution of over-standard sites was uneven, and Cd content was significantly different. Over-standard rate of No.4 greenhouse was 83.33% and was the highest, and the average content of Cd in soil was 0.535 mg/kg. It was used as a comparative test greenhouse for eight treatments. No.1 greenhouse was selected as the preferred test greenhouse, with three over-standard plots having average Cd concentrations of 0.530, 0.568 and 0.792 mg/kg. The comparative test results showed that after 8 months of remediation, the content of available Cd in the treatment of hydroxyapatite+rice biochar+deeper ploughing(T6) was reduced by 32.55% compared with CK(the control) and 24.96% than 2 months of remediation. The content of available Cd using the treatment of potassium dihydrogen phosphate+rice biochar+deeper ploughing(T7) decreased by 47.88% compared with CK and 31.00% than 2 months of remediation. The preferred remediation test results showed that in the treatment of hydroxyapatite+rice biochar+deeper ploughing: the mean Cd content decreased from 0.489 to 0.372 mg/kg, reducing by 23.86%, and the mean did not exceed the standard. Compared with CK, the mean content of available Cd decreased by 10.71% after 8 months, and the lowest content of available Cd in three treatments was 0.133 mg/kg. In addition, the Cd content, bioconcentration factor(BCF) and translocation coefficient(TF) of bean aboveground plants were decreased by 15.86%, 23.68% and 25.77%, respectively when compared with CK. Rice biochar+hydroxyapatite +deeper ploughing is a favoured technology for the remediation of Cd-contaminated greenhouse vegetable fields.

Review on the Pollution-free,Green and Organic Vegetables

This article reviews the concepts, origin and development of pollution-free, green and organic vegetables; then discusses the certification methods, production standard and development orientation of them, which has greatly directive significance for vegetable production and consumption.

盆底超声检查和Green分型诊断产妇产后早期盆底结构及压力性尿失禁

目的:探究盆底超声检查和Green分型在产妇产后早期盆底结构及压力性尿失禁(SUI)诊断中的价值。方法:选取2021年3月-2023年3月本院就诊经产妇204例,根据产后早期(6~8周)SUI发生情况分为SUI组(82例)和非SUI组(122例)。检查产妇静息和Valsalva动作状态下膀胱颈距耻骨联合下缘的距离(BSD)、膀胱尿道后角(PUA)、膀胱颈移动度(BND)和尿道旋转角(UR),对比Green分型;采用受试者工作特征(ROC)曲线分析相关参数诊断SUI价值。结果:静息状态下,两组盆底超声参数无差异(P>0.05);SUI组Valsalva动作状态下的BSD、PUA、BND和UR值均大于非SUI组,Green分型Ι型占比(25.6%)低于非SUI组(59.8%)(均P<0.05)。ROC曲线分析,Green分型曲线下面积(AUC)0.579,对SUI诊断价值不佳(P=0.057),Valsalva动作状态下BSD(AUC=0.758)、PUA(AUC=0.743)、BND(AUC=0.769)和UR(AUC=0.705)对SUI诊断价值良好(均P<0.05)。结论:盆底超声检查和Green分型能有效评估经产妇早期盆底结构状况,前者可诊断SUI。

Effects of Superphosphate Addition on NH_3 and Greenhouse Gas Emissions During Vegetable Waste Composting

To study the effects of superphosphate（SP） on the NH_3 and greenhouse gas emissions,vegetable waste composting was performed for 27 days using 6 different treatments. In addition to the controls,five vegetable waste mixtures（0.77m^3 each） were treated with different amounts of the SP additive, namely, 5%, 10%,15%, 20% and 25%. The ammonia volatilization loss and greenhouse gas emissions were measured during composting.Results indicated that the SP additive significantly decreased the ammonia volatilization and greenhouse gas emissions during vegetable waste composting. The additive reduced the total NH_3 emission by 4.0% to 16.7%. The total greenhouse gas emissions（CO_2-eq） of all treatments with SP additives were decreased by 10.2% to 20.8%, as compared with the controls. The NH_3 emission during vegetable waste composting had the highest contribution to the greenhouse effect caused by the four different gases.The amount of NH_3（CO_2-eq）from each treatment ranged from 59.90 to 81.58 kg/t; NH_3（CO_2-eq） accounted for 69% to 77% of the total emissions from the four gases. Therefore, SP is a cost-effective phosphorus-based fertilizer that can be used as an additive during vegetable waste composting to reduce the NH_3 and greenhouse gas emissions as well as to improve the value of compost as a fertilizer.

水禽细小病毒SYBR Green Ⅰ荧光定量PCR检测方法的建立与应用

为了建立水禽细小病毒(WPV)快速检测方法,根据序列比对结果在水禽细小病毒NS基因SF3保守区域内设计特异性引物,建立SYBR Green Ⅰ荧光定量PCR通用检测方法。该方法的扩增效率(E)为90.0%,相关系数(R~2)=0.99,标准曲线方程为y=-3.607x+38.77;除WPV出现S形扩增曲线外,新城疫病毒(NDV)、H9亚型禽流感病毒(H9 AIV)、鸭坦布苏病毒(DTMUV)、鸭肝炎病毒(DHAV)、鸭肠炎病毒(DEV)、鸭呼肠孤病毒(DRV)样品均未出现S形阳性扩增曲线;批内变异系数(CV)为0.15%~0.23%,批间变异系数为0.09%~0.28%。结果表明,SYBR Green Ⅰ荧光定量PCR检测方法重复性好、灵敏度高和特异性强。临床样品检测结果表明,SYBR Green Ⅰ荧光定量PCR与普通PCR的符合率达98.4%,灵敏度是普通PCR的1 000倍。SYBR Green Ⅰ荧光定量PCR检测方法不仅能定性检测WPV,还可以进行定量检测,可用于种鸭场、种鹅场的WPV净化检测,也可用于WPV临床大量样品的快速检测。

Emission Characteristics of Soil Nitrous Oxide from Typical Greenhouse Vegetable Fields in North China

To make clear the emission characteristics of soil N20 from typical green- house vegetable fields in North China, an experiment was conducted in greenhouse tomato field in Shouguang city, Shandong province, China＇s ＂Home of Vegetables＂. The N2O fluxes were observed in four experimental treatments, as follows： none N fertilizer （CK）, single organic fertilizer （OM）, conventional fertilization （FP） and opti- mized and reduced nitrogen fertilization （OPT）, by a close chamber-gas chromato- graph method. The effects of different fertilization treatments on N2O emission and tomato yield were analyzed. The results showed that following the fertilization and ir- rigation, the pulsed emissions of N2O were measured. The N2O emission peak ap- peared after basal fertilizer application and irrigation and could be maintained for about 20 days. While the N2O emission peak caused by topdressing was smaller and last only 3-5 days. The statistical analysis showed that the N2O fluxes were affected by air temperature, soil temperature and WFPS at soil depth of 3 cm. The total contents of soil N2O fluxes had significant differences among experimental groups. The total content orderly was FP of 14. 77 kg/hm^2, OPT of 9. 73 kg/hm^2, OM of 6.84 kg/hm^2 and CK of 2.37 kg/hm^2. The N~：~ emission coefficient ranged from 0.83%-1.10%,which was close to or more than the recommended value （1.0%） by IPCC. Compared with the FP treatment, the tomato yield in OPT treatment, whose application rate of chemical N fertilizer decreased by about 60%, increased by 2.2%. Under the current management measures, the reasonable reduction on ap- plicaUon rate of organic manure and chemical nitrogen fertilizer could effectively re- duce the N=O emissions in greenhouse vegetable fields.