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.

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.

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.

Sulfur phase and sulfur removal in high sulfur-containing bauxite

The sulfur phase in high sulfur-containing bauxite was studied by an X-ray diffraction analysis and a chemistry quantitative analysis.The methods for the removal of different shaped sulfur were also discussed.The results show that sulfur phases in high sulfur-containing bauxites exist in the main form of sulfide sulfur （pyrite） or sulfate sulfur,and the main sulfur forms of bauxites from different regions are not the same.Through a combination of an X-ray diffraction analysis and a chemistry quantitative analysis,the sulfur phases of high sulfur-containing bauxite could be accurately investigated.Deciding the main sulfur form of high sulfur-containing bauxite could provide theoretical instruction for choosing methods for the removal of sulfur from bauxite,and an oxidizing-roasting process is an effective way to remove sulfide sulfur from high sulfur-containing bauxite,the content of S^2-in crude ore in the digestion liquor is above 1.7 g/L,but in the roasted ore digestion liquor,it is below 0.18 g/L.Using the sodium carbonate solution washing technology to wash bauxite can effectively remove sulfate sulfur,the content of the total sulfur in ore is lowered to below 0.2% and can meet the production requirements for the sulfur content.

Effect of Highly Efficient Nutrient Solution of Biogas Slurry on Yield and Quality of Vegetables

[Objective] The paper aimed to study highly efficient utilization of biogas slurry and the effect of highly efficient biogas slurry on vegetables,so as to provide basis for wide and effective application of biogas slurry.[Method] Using secondary aerobic fermentation technology,a small amount of humic acid was added to biogas slurry to enhance the biological activity of biogas slurry.Through greenhouse experiment,the effect of highly efficient nutrient solution of biogas slurry on yield and quality of green pepper,tomato and cucumber was studied.[Result] Compared with control and traditional application of biogas slurry,application of highly efficient nutrient solution of biogas slurry increased the yield of green pepper,tomato and cucumber,and the increase extents were 12.4%,47.4%,19.9% and 2.7%,15.9%,9.1%,respectively.Compared with traditional application of biogas slurry,application of highly efficient nutrient solution of biogas slurry significantly increased Vc content of green pepper and cucumber with the increase extent of 16.8% and 43.8%,respectively.[Conclusion] Application of highly efficient nutrient solution of biogas slurry can effectively promote the yield of green pepper,tomato and cucumber and change the qualities of vegetables,and significantly enhance the biological activity of biogas slurry.

Design and Development of Web-based Expert System for the Diagnosis of Disease and Pests of Fruits and Vegetables

According to the requirements of agricultural production and usem, taking diagnosis and decision-making of prevention for common diseases and pests in fruits and vegetables in southern China as the core, with communication and sharing as principle, adopted diagnosis, inquiries and guiding prevention of diseases and pests in fruits and vegetables as purpose, expert examination system of plant disease and pests in fruits and vegetables based on Web highly integrates the knowledge and prevention techniques of common diseases and pests for main fruit and vegetable in south China. In this system, the users can browse and inquiry the information about the fruit and vegetable diseases and pests, as well as their diagnosis and control. The implementation of the system plays an active role in promo- ting plant protection knowledge and guiding farms to scientifically control diseases and pests in fruits and vegetables

Effects of Insect Acoustic and Music Acoustic Frequency on the Growth of 6 Kinds of Vegetables

[Objective] The aim was to study the effects of different acoustic frequency of insect sound （IS） and insect-music mixed sound （MS） treatment on the growth of 6 kinds of vegetables.[Method] The insect acoustic group,insect-music mixed group and normal control group were designed to determine the related indices of 6 kinds of vegetables in unified management regularly.[Result] After different acoustic frequency treatment,besides soybean plant height,dry root weight of cabbage and greengrocery,there was significant difference of plant height,fresh weight and dry weight between the other vegetables and control.Under acoustic frequency treatment,the growth situations of six kinds of vegetables were better than control.In the growth period,acoustic frequency treatment could promote height growth （except soybean） and edible part yield.[Conclusion] Both of IS and MS could promote the plant growth,but their effects had difference.

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.

Nutritional Value and Planting Techniques of Several Wild Vegetables in Composite

The nutritional components and utilization value of such 6 wild vegetables as Gynura divaricata, Kalimeris indica, Artemisia argyi H. Lev. ＆ Vaniot, Artemisia selengensis, Lysimachia clethroides and Taraxacum mongolicum were introduced, so as to promote the development and utilization of wild vegetable resources. The culture management of these 6 wild vegetables was also introduced, so as to provide reference for culture of wild vegetables.

Agricultural Application of Multi-functional Leaf Vegetables Light-conversion Film

[Objective] The aim was to detect property of light-conversion agricultural films in order to resolve problems existing of greenhouses and in cultivation of out- of-season vegetables. [Method] Light-conversion films and common films were com- pared in terms Of light, air and soil temperatures. [Result] Vegetable greenhouse performed better in transmission of light, which would also improve air and soil tem- perature. [Conclusion] The comprehensive properties of vegetable light-conversion films proved better compared with common greenhouse, which improves light condi- tions for crops.

Tolerance and Cumulative Effect of Zinc Pollution of Three Vegetables in Central China

[Objective] The aim was to study the differences of tolerance and cultivate effect of Zn pollution in three vegetables in central China. [Method] Seed germination tests and pot experiments of radish （Raphanus Sativus L.）,pakchoi（Brassica campestris ssp. Chinensis） and edible amaranth （Amaranthus mangostanus） under Zn stress with different concentrations were carried out,to study the effects of different treatments on seed germination rates,seedling growth,biomass and Zn contents of vegetables. [Result] Zn stress with concentration of 2 000 mg/L had no significant influence on seed germination rates of pakchoi and radish,but had significant influences on seed germination rate of amaranth. Zn stress with concentrations of 500 and 2 000 mg/L had significant influence on seedling growth of the three vegetables. The tolerance of radish to excessive Zn toxicity was stronger than that of pakchoi and amaranth. In addition,Zn contents in edible part of the 3 vegetables in each treatment were lower than standard of food hygiene of China. When the added Zn was 100-1 000 mg/kg soil,the Zn contents in radish shoot and root parts were both lower than that in pakchoi and amaranth. [Conclusion] Radish had better tolerance on Zn pollution than pakchoi and amaranth,and was more suitable to be planted in Zn-contaminated soils than the other two vegetables in central China to reduce Zn contamination risk in food chain.

Status and Health Risk Assessment of Heavy Metal Contamination in Vegetables

[Objective] This study aimed to protect people＇s food hygiene safety and improve the quality of vegetables. [Method] The residual contents of heavy metals （Cu, Zn, Pb, Cd and Cr） in the vegetables purchased from local market of Yuhui District, Bengbu City were determined. According to the standard limits of the International Commission on Radiological Protection （ICRP）, the health risk of vegetables with excessive heavy metal residues was assessed. [Result] The Pb content in some commercially purchased vegetables exceeded the national standard. The health risk of the vegetables contaminated by Pb was 4.467×10^-7a^-1, which was lower than the standard limit （5.0×10^-5a^-1） of the ICPR. Thus, the vegetables posed no significant risk to human health. [Conclusion] The risk of commercially purchased vegetables to human health was low.

Temporal-spatial Distribution Model of Cold Chain Logistics for Vegetables

[Objective] The aim was to study on temporal-spatial distribution model of cold chain logistics for vegetables. [Method] Broccoli was taken as an example. Detailedly, time-space distribution model of cold chain logistics for broccoli was proposed from standpoints of costs and benefits based on changes of time and space, and a comprehensive evaluation was made on timeliness, efficiency, risks, added- value of products and satisfaction of information in cold-chain logistics. [Result] The efficiency of cold chain logistics for vegetable can be greatly improved by temporal- spatial distribution model of cold chain logistics. [Conclusion] Costs and benefits of vegetables in temporal-apstial distribution could be evaluated by the model.

Experiment on Organic Ecotype Soilless Culture of Vegetables

A suitable substrate formula for vegetable cultivation was selected through experimenting on the culture substrate for organic ecotype soilless culture of vegetables, and organic matter content of the substrate was 294% as name that of soil, while the content of N, P and K were 328%, 279% and 192% that of the soil, respectively. Vegetable yield with this substrate was 157%-228% that with the soil.

The Development Status quo and Strategy of Aquatic Vegetables in Hunan

This paper reviews the development of aquatic vegetable production and research in Hunan. The advantages of aquatic vegetable industry in Hunan are discussed in detail on its location, brand, market, planting and processing. And the development strategies of the above-mentioned industry are further analyzed in the paper, such as variety resources, breeding and industrialization.

Effects of Seedling Cultivation Methods on Seedling Cultivation of Major Vegetables

Objective] The alm was to expIore the effects of cuItivation methods on vegetabIe growth in seedIing stage. [Method] The test incIuded 4 treatments, as foI-Iows： treatment 1 （T1） where seedIings were cuItivated as per water fiIm-based cuI-tivation and irrigation proceeded reguIarIy; treatment 2 （T2） where irrigation proceed-ed continuousIy as per water fiIm-based cuItivation; treatment 3 （T3） where seedIings were cuItivated as per fIoating nursing; controI treatment （CK） where seedIings were cuItivated as per seedIing-tray cuItivation in order to survey the number of germinated seedIings per tray. [Result] Both of water fiIm-based cuItiva-tion and fIoating nursing took advantages in germination speed and aduIt seedIing rate, compared with tray cuItivation method. [Conclusion] Water fiIm-based cuItivation and fIoating nursing make innovations in water management during seedIing cuItiva-tion, which improve germination speed, aduIt seedIing rate and seedIing quality, making contribution to Iarge-scale production of greenhouse vegetabIes through ap-pIications and practices.

Effects of N, P and K on Output and Nutrient Cycle of Vegetables in Greenhouses

ObjectiveThe aim was to increase farmers’ income and reduce the waste of fertilizer by exploring effects of N, P and K fertilizations on vegetable yields and the accumulation of N, P and K in vegetable and soils. MethodThe fertilization tests were conducted on tomato, cauliflower and celery in greenhouses. ResultWhen N, P and K were not applied in tomato, cauliflower or celery, the yields reduced in 6.0%-13.8% and total annual income reduced by 39 220, 36 902 and 22 023 yuan/hm 2 respectively, suggesting that N, P and K are limiting factors of yield. The absorbed N amounts of tomato and cauliflower were higher compared with celery; the absorbed P amount of cauliflower was higher compared with tomato and celery; the absorbed K amount of tomato was the highest, followed by celery and cauliflower. The absorbed N in tomato fruit was lower than that of cauliflower and the absorbed N amount of other parts of tomato was also lower. Furthermore, the absorbed amounts of P and K by tomato and cauliflower fruits were higher than it absorbed by the other parts, especially the absorbed of K was significantly high. Total absorbed amounts of N, P and K from high to low were cauliflower, tomato and celery. After harvesting of tomato, cauliflower and celery, N, P and K in soils were all higher compared with soils before planting. Influenced by fertilizers, residual N content in soils grown with tomato and residual P content in soils grown with celery both doubled compared with base soils. Cauliflower plants were not applied with organic fertilizer, and residual N and K contents in soils were lower compared with tomato and celery. ConclusionResidual P content in soils is higher, which is a kind of waste and would cause pollution on soils. It is necessary to improve the proportion of organic and inorganic fertilizers in fertilization.

Progress on Light-controlled Preservation Technology of Postharvest Vegetables

Preservation technology of light control has received the widespread atten- tion for its safety, green, environmental-protection, high efficiency. It has become the hotspot in the area of postharvest vegetables preservation. It could mainly be divid- ed into three categories： LED preservation, UV preservation and radiation preserva- tion. This paper systematically reviewed the mechanisms of different preservation technology of light control, summarized the research progress of light-controlled tech- nology in the physiological characteristics regulation, maintenance of nutritional quali- ty and microbial control of postharvest vegetables at home and aborad, and prospected the further studies on preservation technology for postharvest vegetables.

Highly Efficient and Selective Removal of Pb（II） ions by Sulfur-Containing Calcium Phosphate Nanoparticles

A facile one-step co-precipitation method was demonstrated to fabricate amorphous sulfurcontaining calcium phosphate （SCP） nanoparticles, in which the sulfur group was in-situ introduced into calcium phosphate. The resulting SCP exhibited a noticeable enhanced performance for Pb（II） removal in comparison with hydroxyapatite （HAP）, being capable of easily reducing 20 ppm of Pb（II） to below the acceptable standard for drinking water within less than 10 min. Remarkably, the saturated removal capacities of Pb（II） on SCP were as high as 1720.57 mg/g calculated by the Langmuir isotherm model, exceeding largely that of the previously reported absorbents. Significantly, SCP displayed highly selective removal ability toward Pb（II） ions in the presence of the competing metal ions （Ni（II）, Co（II）, Zn（II）, and Cd（II））. Further investigations indicated that such ultra-high removal efficiency and preferable affinity of Pb（II） ions on SCP may be reasonably ascribed to the formation of rodlike hydroxypyromorphite crystals on the surface of SCP via dissolution-precipitation and ion exchange reactions, accompanied by the presence of lead sulfide precipitates. High removal efficiency, fast removal kinetics and excellent selectivity toward Pb（II） made the obtained SCP material an ideal candidate for Pb（II） ions decontamination in practical application.