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Agricultural crop production practices are being developed for organic, sustainable, and environmentally friendly farming systems. Developing efficient and resourceful crop fertilizers is significantly important for future agriculture. Various biofertilizers, such as animal manures, composts, and vegetable byproducts, have been successfully applied in agriculture. Anaerobic digestate, organic matter obtained from animal or plant waste processing during anaerobic digestion into biomass, has become popular due to its versatility, multiple purposes, and facile application methods. Digestate has recently been widely used in agriculture to enrich the soil with nutrients and thus increase crop yields. Several studies have shown that anaerobic digestate is a valuable fertilizer that can be used as a biofertilizer in field and greenhouse horticulture. Also, research has been carried out on the use of digestate in hydroponic horticulture. This review presents the research results and discusses the possibilities of using anaerobic digestate in greenhouse horticulture. Its objective is to provide a comprehensive understanding of the application of digestate from various sources and its impact on the growth, progress, yield, and quality of greenhouse-grown vegetables. [ABSTRACT FROM AUTHOR]

Plastic greenhouses play an important role in vegetable cultivation in China. While evaluations have attributed perfluoroalkyl acid contamination in greenhouse vegetables primarily to irrigation water, the potential contribution from greenhouse plastic films has consistently been overlooked, despite PFAAs' long-standing use as anti-fogging agents. In this study, a comprehensive assessment of PFAA contamination was conducted in greenhouses at the Shouguang vegetable base in China, based on extensive environmental and crop sample collection, followed by analysis using LC-MS/MS. PFAAs are still used in greenhouse plastic film, and their migration to the surface water mist and the air inside the greenhouse was also observed. Elevated levels of PFAA pollution were found near the corner areas of greenhouses with longer service times, leading to further pollution of the soil and nearby vegetables. This is considered as the primary source which may have been caused by PFAAs migrating with condensation from the plastic film and accumulating for decades. However, polluted irrigation water still remains the dominate source of PFAAs in other areas inside the greenhouse. Based on our analysis, we conclude that PFAAs present in plastic films could be the primary contaminant source for vegetables in specific zones. This underscores the urgent need for heightened vigilance towards environmental pollution within agricultural facilities, which currently represent the most prevalent mode of intensive vegetable cultivation in China. [ABSTRACT FROM AUTHOR]

Agricultural crop production practices are being developed for organic, sustainable, and environmentally friendly farming systems. Developing efficient and resourceful crop fertilizers is significantly important for future agriculture. Various biofertilizers, such as animal manures, composts, and vegetable byproducts, have been successfully applied in agriculture. Anaerobic digestate, organic matter obtained from animal or plant waste processing during anaerobic digestion into biomass, has become popular due to its versatility, multiple purposes, and facile application methods. Digestate has recently been widely used in agriculture to enrich the soil with nutrients and thus increase crop yields. Several studies have shown that anaerobic digestate is a valuable fertilizer that can be used as a biofertilizer in field and greenhouse horticulture. Also, research has been carried out on the use of digestate in hydroponic horticulture. This review presents the research results and discusses the possibilities of using anaerobic digestate in greenhouse horticulture. Its objective is to provide a comprehensive understanding of the application of digestate from various sources and its impact on the growth, progress, yield, and quality of greenhouse-grown vegetables.

As the largest organic carbon input to agroecosystems, crop straw can solve the problem of soil quality degradation in greenhouse vegetable fields, harmonize the balance between soil nutrients and energy, and improve soil quality to maintain the sustainable production of greenhouse vegetables. However, the microbial mechanism of the straw decomposition process under different temperatures and fertilization treatments in greenhouse vegetable soils has not been clarified. Soil samples were used to investigate the biology of straw decomposition in the soil at three incubation temperatures (15, 25, and 35 °C) through a soil incubation experiment (60 d) under different fertilization treatments. Fertilization treatments for this long-term field experiment included chemical fertilizer (CF), substitution of half of the chemical N fertilizer with manure (CM), straw (CS), or combined manure and straw (CMS). The results showed that soil hydrolase activities tended to decrease with increasing temperature during straw decomposition. Compared with the CF, organic substitutions (CM, CMS, and CS) increased soil β-glucosidase, β-cellobiosidase, N-acetyl-glucosaminidase, and β-xylosidase activities during straw decomposition. Soil CO2 emission rates were the highest at each incubation temperature on the first day, rapidly declining at 25 °C and 35 °C and slowly declining at 15 °C. The soil CO2 cumulative emissions tended to increase with increasing temperature under different fertilization treatments. PCA showed that the responses of soil enzyme activities to temperature at 7, 15, and 30 d of straw decomposition were stronger than those of fertilization. In summary, both fertilization treatment and incubation temperature could influence soil CO2 emissions by affecting soil physicochemical properties and enzyme activities during straw decomposition, whereas incubation temperature had a stronger effect on straw decomposition than fertilization, as indicated by PLS-PM and three-way ANOVA. Considering the influence for fertilization on the straw decomposition process at different incubation temperatures, the straw applications (CMS and CS) were more suitable to temperature changes. [ABSTRACT FROM AUTHOR]

Purpose: Cover cropping during the summer fallow is a feasible practice for soil residual nitrogen (N) absorption and subsequent N supply in greenhouse vegetables. However, the change in these effects with a progression in the cultivation years of greenhouse vegetables remains unknown. This study aimed to evaluate the effects of different cover crops on the uptake of residual N in soil and N mineralization as affected by the planting years of greenhouse vegetables. Methods: Five soil samples were collected from fields that had been cultivated with greenhouse vegetables for different number of years (0, 5, 10, 15, and 20 years); upper layers (0–30 cm) of the soil were sampled from a major vegetable production area in Xinxiang City, Henan Province, China. Three cover crop treatments were included for each soil sample: no cover crop planted during summer fallow with no straw return (CK), summer maize (Zea mays L.) planted and straw return (SM), and alfalfa (Medicago sativa L.) planted and straw return (A). Pot and incubation experiments were conducted to determine the amounts of N absorbed by cover crops during the fallow and soil N mineralization after cover crop straw return. Results: The effects of cover crops on soil residual N absorption and subsequent N mineralization changed with cover crop types and greenhouse vegetable planting years. SM performed better as a cover crop than A in crop biomass development (on average 6.67 times larger), soil residual N absorption (4.46 times larger), and loss (3.61 times smaller) control, regardless of the greenhouse vegetable planting years. In terms of soil net N mineralization and straw-induced N mineralization, SM was inferior to A (1.15 and 2.12 times smaller). With the increase of planting years, total biomass yield and N uptake by the SM increased, whereas these parameters decreased for treatment A due to the plants' different tolerance to soil available N and pH (pondus hydrogenii). For all cover crop treatments, with the increase of greenhouse vegetable planting years, net N mineralization of the soil increased due to the positive contribution of soil organic matter, whereas straw-induced N mineralization decreased due to the negative regulation of accumulated soil nitrate nitrogen. Conclusions: Non-legumes, as represented by SM, were a good choice for cover cropping regardless of the greenhouse vegetable cultivation years. However, attention should be paid to N supplementation at an early stage of subsequent crop cultivation, especially in newly built greenhouse vegetables. [ABSTRACT FROM AUTHOR]

Plastic greenhouses play an important role in vegetable cultivation in China. While evaluations have attributed perfluoroalkyl acid contamination in greenhouse vegetables primarily to irrigation water, the potential contribution from greenhouse plastic films has consistently been overlooked, despite PFAAs’ long-standing use as anti-fogging agents. In this study, a comprehensive assessment of PFAA contamination was conducted in greenhouses at the Shouguang vegetable base in China, based on extensive environmental and crop sample collection, followed by analysis using LC-MS/MS. PFAAs are still used in greenhouse plastic film, and their migration to the surface water mist and the air inside the greenhouse was also observed. Elevated levels of PFAA pollution were found near the corner areas of greenhouses with longer service times, leading to further pollution of the soil and nearby vegetables. This is considered as the primary source which may have been caused by PFAAs migrating with condensation from the plastic film and accumulating for decades. However, polluted irrigation water still remains the dominate source of PFAAs in other areas inside the greenhouse. Based on our analysis, we conclude that PFAAs present in plastic films could be the primary contaminant source for vegetables in specific zones. This underscores the urgent need for heightened vigilance towards environmental pollution within agricultural facilities, which currently represent the most prevalent mode of intensive vegetable cultivation in China.

Background: The purpose of this research is to investigate the concentration of heavy metals and nitrate in the fruit of pepper, eggplant, cucumber, and tomato cultivated in greenhouses in Kermanshah County. Methods: After sample preparation and extraction, the concentration of heavy metals with an atomic absorption and nitrate (No3-) concentration were determined by a spectrophotometer at a wavelength of 410 nm. Subsequently, Human health risks were assessed using the Health Assessment Index of non-cancer diseases. Results: Pepper exhibited elevated concentrations of nickel (Ni) and cadmium (Cd), while eggplant displayed higher levels of Ni, lead (Pb), and Cd. Cucumbers demonstrated an increased concentration of Cd, and tomatoes exhibited higher copper (Cu) and Cd levels, surpassing the standards set by the World Health Organization (WHO). A significant difference was observed between the studied vegetables and the concentration of heavy metals and nitrate. The highest daily intake rate and risk index of heavy metals and No3-were observed in eggplant and tomato. Conclusion: The risk index of heavy metals was found to be below 0.1. However, the risk index for No3-exceeded 1. Therefore, it is recommended to study the potential sources of heavy metals contamination in the soil, water, and dust of the county to better understand the possible routes of food contamination. [ABSTRACT FROM AUTHOR]

Introduction Silicon (Si) is not an essential element for the growth of plants, but its role in improving the yield by reducing the environmental stresses and crop durability is very important. Despite the abundance of Si in the soil, the amount of dissolved Si available for herbal absorption might be limited. Therefore, using this useful element through foliar application can be effective in the growth of the plants such as eggplant. On the other hand, profitability is dependent on the high yield and quality per unit area in producing greenhouse vegetables.Materials and Methods To study the effect of foliar application of Si fertilizer from the source of Khazra Chelated Silicon (commercial brand, contains 2% chelated silicon for plant at pH 3 to 11 and no silicate in the form of salt) in different stages of the growth of eggplant and bush pruning in hybrid eggplant, a greenhouse experiment was conducted in a soil environment as a split-plot in a randomized complete block design with 3 replications in Minab region. In this experiment, the consumption of Si fertilizer as the main factor at 4 levels (0 and 2 per thousand in the vegetative phase, 2 per thousand in the reproductive phase and 2 per thousand at the two vegetative and reproductive phases) and the type of pruning as a sub-factor in 4 levels (two-branch training system, three-branch training system, four-branch training system and no training system) were applied. Eggplant seeds were transplanted in an environment containing sphagnum in November and then at four-leaf stage they were transferred to the main field in December. The distance between the rows was one meter and the distance between the plants in the row was 45 cm. After positioning the plant in the greenhouse and reaching the appropriate growth, pruning and foliar application of Si fertilizer began and in the treatment without fertilizer, spraying with pure water was used. Silicon fertilizer was sprayed on the eggplant leaves according to the instructions recommended by the manufacturer every eight days. Once the eggplants reached a suitable reproductive growth and started fruiting, fruit thickness, fruit length, the weight of each fruit, the number of the fruits on each plant, and finally the yield of each plant were recorded in each pick. To evaluate the effect of Si on the durability of eggplant after picking, 3 fruits harvested from each treatment were first weighed by a digital scale, and then kept at room temperature for 2 weeks and after two weeks, the weight of each fruit was measured again. Based on two recorded weights, the percentage of fruit weight loss was calculated. Furthermore, to evaluate the effect of silicon fertilizer and plant pruning on resistance to fungal diseases, scores, from 1 to 9, were given to the plants in each treatment. Plants without any fungal infection were assigned a score of 1, and completely infected plants were assigned a score of 9.Results and Discussion The results showed that pruning improved the fruit length, the plant height, the fruit weight in each plant, and the plant yield and reduced the percentage of fungal infection in the plant. Moreover, the silicon foliar application positively affected the number of the fruits in each plant and increased the durability of fruits after harvesting. Silicon foliar application in the two vegetative and reproductive stages together and plant pruning in a four-branch way resulted in maximum plant yield, improved crop quality, and improved greenhouse management. The intensity of fungal infection was affected by different levels of silicon, plant pruning, and the interaction of the two factors at a probability level of five percent. Comparison of interaction averages showed that pruning and foliar application in vegetative and reproductive stages together significantly reduced fungal infection in the greenhouse. The highest intensity of fungal infection was related to plants without pruning and lack of silicon. Pruning improves airflow and modulates humidity in the plant canopy and as a result eliminates the proper conditions for fungal growth. Silicon also prevents fungal penetration into plant cells by depositing in the plant cell wall and strengthening plant tissue, and as a result inhibits fungal growth in the plant. Marschner (2012) reported that silicon would increase resistance to fungal and bacterial diseases and pests. Plant diseases are a major threat to agricultural production because they cause a serious loss of yield and quality of the crop. Numerous studies have reported that Si is effective in controlling diseases caused by fungal and bacterial pathogens in various plant species. Furthermore, given that one of the challenges for producers to deliver high-quality crops to the target market is their durability after harvesting, it seems that silicon foliar application at the two vegetative and reproductive stages might be effective to overcome such a challenge. Choosing a training system depends to a large extent on the ease of work in the greenhouse, the production system, and the superiority of the production rate. On the other hand, a significant increase in yield and crop quality was reported for barley, rice, sugarcane, tomato, cucumber, soybean, and bamboo due to Si consumption during the growth. Another important feature of silicon is that it increases plant damage under biological and non-biological stress conditions as well as resistance against stress.Conclusion According to the results, four-branch training system of eggplant and also silicon foliar application in the two vegetative and reproductive phases of greenhouse eggplant improved the yield components and increased the durability after harvesting. Pruning the plant into four branches also improved yields. Therefore, using silicon with four-branch training system is recommended, especially in traditional greenhouses without proper ventilation systems.

As the largest organic carbon input to agroecosystems, crop straw can solve the problem of soil quality degradation in greenhouse vegetable fields, harmonize the balance between soil nutrients and energy, and improve soil quality to maintain the sustainable production of greenhouse vegetables. However, the microbial mechanism of the straw decomposition process under different temperatures and fertilization treatments in greenhouse vegetable soils has not been clarified. Soil samples were used to investigate the biology of straw decomposition in the soil at three incubation temperatures (15, 25, and 35 °C) through a soil incubation experiment (60 d) under different fertilization treatments. Fertilization treatments for this long-term field experiment included chemical fertilizer (CF), substitution of half of the chemical N fertilizer with manure (CM), straw (CS), or combined manure and straw (CMS). The results showed that soil hydrolase activities tended to decrease with increasing temperature during straw decomposition. Compared with the CF, organic substitutions (CM, CMS, and CS) increased soil β-glucosidase, β-cellobiosidase, N-acetyl-glucosaminidase, and β-xylosidase activities during straw decomposition. Soil CO2 emission rates were the highest at each incubation temperature on the first day, rapidly declining at 25 °C and 35 °C and slowly declining at 15 °C. The soil CO2 cumulative emissions tended to increase with increasing temperature under different fertilization treatments. PCA showed that the responses of soil enzyme activities to temperature at 7, 15, and 30 d of straw decomposition were stronger than those of fertilization. In summary, both fertilization treatment and incubation temperature could influence soil CO2 emissions by affecting soil physicochemical properties and enzyme activities during straw decomposition, whereas incubation temperature had a stronger effect on straw decomposition than fertilization, as indicated by PLS-PM and three-way ANOVA. Considering the influence for fertilization on the straw decomposition process at different incubation temperatures, the straw applications (CMS and CS) were more suitable to temperature changes.

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. [ABSTRACT FROM AUTHOR]

• Eight spectrum imaging techniques reviewed in this article refer to RGB imaging, Multispectral/Hyperspectral imaging, Chlorophyll fluorescence imaging, Thermal imaging, Raman spectral imaging, X-ray imaging, Magnetic resonance imaging and Terahertz spectral imaging. • The application of spectrum imaging technology in the study of biochemical, physiological, morphological and yield traits of greenhouse vegetable was reviewed. • Four potential solutions are proposed: multi-source fusion and phenotype platform development, innovative data analysis methods, development of portable devices, and analysis combined with underlying mechanisms. Greenhouse vegetables have become increasingly important in global crop production due to their ability to be cultivated out of season and ensure a year-round supply of vegetables. With the rapid advancement of "phenomics", accurately measuring the phenotypic information of greenhouse vegetables is crucial for enhancing both their yield and quality. Over the past two decades, various technologies have been developed for phenotypic detection of fruits, vegetables, and other crops, based on the interaction between electromagnetic waves and matter. While some articles have investigated these applications, there is a lack of a systematic review specifically focused on the phenotypic detection of greenhouse vegetables. In this review, RGB imaging, Multispectral/Hyperspectral imaging, Chlorophyll fluorescence imaging, Thermal imaging, Raman imaging, X-ray imaging, Magnetic resonance imaging, and Terahertz imaging are collectively referred to as spectrum imaging technologies. We provide a comprehensive review of the origins, research progress over the past twenty years, and current challenges of spectrum imaging in the field of greenhouse vegetable research. It focuses on identifying the most suitable spectrum imaging technologies for detecting four categories of phenotypic traits: biochemical, physiological, morphological, and yield-related traits. Additionally, we highlight the issues that need optimization in the practical application of these technologies and the bottlenecks faced in different trait studies. Finally, based on existing research, we propose several potential solutions and future research directions to maximize the utility of spectrum imaging technologies in the phenotypic detection of greenhouse vegetables. [ABSTRACT FROM AUTHOR]

Agricultural extension is a key instrument to bridge the gap between new technologies and farmers. As a popular extension approach, farmer field schools (FFS) usually improve farmers' knowledge and crop productivity. This study aims to quantify the heterogeneous impact of FFS on the cognition and adoption of multiple new agricultural technologies. In this study, we apply Tobit models to estimate the impact of FFS on technology extension regarding farmers' cognition and adoption rates of different technologies, using data collected for 274 tomato and cucumber farm households in Beijing, China. We find that the FFS programmesignificantly increased farmers' cognition and adoption of new agricultural technologies. We also find that the effects of FFS on extension vary in different categories of new technology. Particularly, we find that the extension of facility technologies is difficult, and new varieties are easy to disseminate but difficult to adopt by farmers. We conclude that FFS is an important channel for the extension of new agricultural technologies. At the same time, attention should be paid to the design of the FFS programme, adjusting to the attribute of different technologies. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Applied Entomology is the property of Chinese Journal of Applied Entomology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The greenhouse vegetable industry play an important strategic role in the adjustment of agricultural transformation mode and the reform of supply side in Heilongjiang Province. Facility horticulture in Heilongjiang Province develops rapidly in recent years, technical support is in great demand, but the experts' technology support for facility horticulture is far from enough. Experts' on-site guidance costs much time and money in the countryside, while the service efficiency is very low. To solve this urgent problem, the architecture of "greenhouse vegetable intelligent terminal system based on cloud service" and the key technologies of implementation (low-cost IoT, distributed real-time operating architecture, virtual expert service, neural network image recognition and mobile terminal service) were put forward. Based on expert services, supplemented by data mining technology, IoT devices were used as expert's remote perception means, smart phones as user terminals, cloud service for integrating knowledge, resources and Internet of Things data to provide vegetable experts and greenhouse vegetable users with high information acquisition, storage, analysis,decision-making capabilities and effective solutions. Experts could view vegetable production status in greenhouses remotely through the Internet, get image and growth environment data, then provide remote guidance to vegetable farmers through the system, expert knowledge would be stored, mined and reused by the system. The Internet of Things system could automatically send out early warning information by judging the air temperature, humidity, illumination intensity and soil moisture in greenhouse. The application of knowledge map and neural network technology would reduce the workload of experts and increase concurrent processing capability of services at the same time. At present, part of this research has been applied in different user groups such as agricultural research departments, enterprises, vegetable cooperatives and farmers in Heilongjiang Province. The system can provide experts with remote inquiry means of greenhouse vegetable production environment, and has the characteristics of simple deployment and low cost. It is suitable for various greenhouse vegetable scenarios, including fruit and edible fungi. In order to popularize this technology in greenhouse vegetable production in China, and achieve an efficient experts' technical support, this research also proposed technical solutions of a large-scale application scenario through cloud computing in future.

Greenhouse vegetables have been one of the fastest growing and best performing Albanian agrifood subsectors. This paper analyses the current state of coordination and recent developments in the greenhouse vegetable value chain, based on a structured farm survey. The results show that vertical cooperation is not sustainable and most greenhouse vegetable farmers do not use written contracts. Furthermore, most farmers do not carry out soil or water analysis. Albanian farmers do not trust the quality of inputs while claiming that (input) prices are unfair and unreasonable. This is, to a large extent, a result of "spot market" coordination, which cannot guarantee traceability and standards compliance; therefore Contract Farming is the adequate tool to address these gaps. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Owing to the excessive use of pesticides in greenhouses, soils and vegetables herein are more heavily contaminated than those in non-facility cultivation. Based on a developed QuEChERS (quick, easy, cheap, effective, rugged, and safe) method, four methods of sample pretreatment were compared for the monitoring of six pesticides (bifenthrin, chlorfenapyr, lambda-cyhalothrin, pyridaben, pyrimethanil, and pyriproxyfen) commonly used in greenhouses of Hubei Province. Using different extraction strategies and purification methods with different solid phases and eluent mixtures, an optimised method for residual analysis in soil and plant samples via gas chromatography–mass spectrometry was determined. The detection limits of the method for the six pesticides ranged from 0.1 to 0.8 µg/kg in three spiked matrixes and average recovery rates of 80.6–118.3% were achieved for single target pesticides at spiked concentrations of 0.1, 1.0, and 10 mg/kg with standard deviations of 2.4–8.4%. Health risk assessment was conducted through the analysis of greenhouse soil and vegetable samples at Pengdun, a typical agricultural greenhouse facility in Jingmen, Hubei Province, central China. Based on the quantification of the six target compounds in four vegetable types, only pyriproxyfen in tomato exceeded the Canadian and WHO/FAO maximum residue limits. No chronic, acute, non-carcinogenic, or carcinogenic health risks to farmers working in the greenhouses or consumers of the vegetables were observed for all age groups in the study area. Residual results showed that pyridaben is the most often quantified pesticide in all greenhouses of the study area. Pesticide combinations, including bifenthrin, chlorfenapyr, and pyridaben, were similar for cucumbers and eggplants. Nevertheless, simultaneous detection of multiple contaminants and health risk assessment are required because combined contamination may lead to much higher toxicity to both workers and consumers with the emergence of pesticide resistance and the development of new pesticide products. The quantification limits of the developed method for the simultaneous analysis of the six target pesticides showed high reliability, accuracy, effectiveness, and applicability. [ABSTRACT FROM AUTHOR]

Residual levels of six priority phthalate esters (PAEs) compounds in top soils and vegetables of 40 selected greenhouses in two typical facility vegetable greenhouse production areas of Jingmen (Hubei, central China) were determined. Total concentrations of six target PAEs (Σ6PAEs) in 72 vegetable and 40 soil samples ranged from 862 ± 209 to 4260 ± 385 µg kg−1 (dry weight, DW), and from 1122 ± 156 to 4134 ± 272 µg kg−1 (DW), respectively. Di-n-butyl phthalate and di-(2-ethylhexyl) phthalate (DEHP) are the two most frequently and massively detected in all samples. The highest Σ6PAEs appeared in leaf samples of Tuanlin, vegetable fruits of Zhongxiang and soils of Tuanlin. No carcinogenic risk was posed based on the results of health risk assessment, but non-carcinogenic risk of DEHP to children less than 6 years old in Tuanlin (all 24 sampling sites) and Zhongxiang (4/16 sampling sites) and people older than 6 years old in Tuanlin (19/24 sampling sites) were achieved from hazard quotient values. The contamination risk problem of PAEs in Tuanlin deserves greatest concern in Jingmen. Combined with the results of our former study, the health risks of target pollutants were clarified and the lack of survey data on PAE concentrations in facility vegetable greenhouses of central China was filled in. Due to high residuals and significant non-carcinogenic risk values, DEHP should be nominated as priority PAEs in China. Our study suggested better regulation for PAEs control in intensively managed greenhouses and references for revision of Chinese environmental standards. [ABSTRACT FROM AUTHOR]

Agronomic biofortification of horticultural crops using plant growth-promoting rhizobacteria (PGPR) under crop residue incorporation systems remains largely underexploited. Bacillus subtilis (B1), Bacillus laterosporus (B2), or Bacillus amyloliquefaciens (B3) was inoculated on soil containing chili residue, while chili residue without PGPR (NP) served as the control. Two hybrid long cayenne peppers, succeeding a leaf mustard crop were used in the intensive cultivation study. Net photosynthesis, leaf stomatal conductance, transpiration rate, photosynthetic water use efficiency, shoot and root biomass, and fruit yield were evaluated. Derivatives of folate, minerals, and nitrate contents in the pepper fruits were also assessed. B1 elicited higher net photosynthesis and photosynthetic water use efficiency, while B2 and B3 had higher transpiration rates than B1 and NP. B1 and B3 resulted in 27–36% increase in pepper fruit yield compared to other treatments, whereas B3 produced 24–27.5% and 21.9–27.2% higher 5-methyltetrahydrofolate and total folate contents, respectively, compared to B1 and NP. However, chili residue without PGPR inoculation improved fruit calcium, magnesium, and potassium contents than the inoculated treatments. ‘Xin Xian La 8 F1’ cultivar had higher yield and plant biomass, fruit potassium, total soluble solids, and total folate contents compared to ‘La Gao F1.’ Agronomic biofortification through the synergy of Bacillus amyloliquefaciens and chili residue produced better yield and folate contents with a trade-off in the mineral contents of the greenhouse-grown long cayenne pepper.

In recent years, through financial subsidies, Shouguang City has promoted the application of electrostatic sprayer, dual-purpose fog and mist sprinkler machine, Bacillus cereus, flame disinfection service based on fine rotary tillage and multi-functional plant protection machine and other new green prevention and control products and technologies for the greenhouse vegetable in the city. As a result, the utilization rate of pesticides was increased by more than 5%, and the application rate was reduced by more than 10%. [ABSTRACT FROM AUTHOR]

Copyright of Mediterranean Agricultural Sciences is the property of Akdeniz Universitesi Ziraat Fakultesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

China's small-scale agricultural producers face many challenges to increasing productivity and efficiency. In recent years, the Chinese government has provided support for farmer professional cooperatives (FPCs) to connect small farms with upstream and downstream processes in the food supply chain. This study combines propensity score matching and sample selection-corrected stochastic production frontier analysis to estimate the impacts of FPC participation by greenhouse vegetable producers on technical efficiency and income. Results indicate that FPCs help participants improve returns to scale and marginal returns to land and labor, increase technical efficiency, and obtain ¥4,460 (18%) greater income per greenhouse than nonparticipants. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A new rapid modified one-step QuEChERS (quick, easy, cheap, effective, rugged, and safe) approach was developed for the simultaneous determination of 20 perfluoroalkyl substances (PFASs) from samples of cucumber, lettuce, eggplant, tomato, and leek. Several parameters were optimized. Similar pretreatment approaches were employed for comparison; the results verified the satisfactory performance of this new method. The detection limits of this method for the selected matrices ranged from 0.003 to 0.034 μg kg−1, and the method was verified to be satisfactory in terms of precision, accuracy, and matrix effects. 35 greenhouse vegetable samples were determined. PFASs were detected in 26 samples, with perfluorooctanoic acid (PFOA) being detected most frequently and much higher levels of PFBA and PFPeA being found in some samples. The total PFAS concentrations ranged from not detectable to 0.683 μg kg−1. This method could be applied for large scale determination of vegetables to research the migration and accumulation trends of PFASs from the environment to crops in the future. Image 1 • General one-step QuEChERS methods were developed to determine of PFASs in vegetables.. • Method is rapid, simple, and efficient with low MDLs, and good precision and accuracy. • Representative vegetables were employed to establish the proposed procedure. • Good applicability was verified with 15 kinds of vegetable samples. • PFOA was most frequently detected, some samples showed high levels of volatiles. [ABSTRACT FROM AUTHOR]

Elevated atmospheric CO2 (eCO2) enhances the yield of vegetables and could also affect their nutritional quality. We conducted a meta-analysis using 57 articles consisting of 1,015 observations and found that eCO2 increased the concentrations of fructose, glucose, total soluble sugar, total antioxidant capacity, total phenols, total flavonoids, ascorbic acid, and calcium in the edible part of vegetables by 14.2%, 13.2%, 17.5%, 59.0%, 8.9%, 45.5%, 9.5%, and 8.2%, respectively, but decreased the concentrations of protein, nitrate, magnesium, iron, and zinc by 9.5%, 18.0%, 9.2%, 16.0%, and 9.4%. The concentrations of titratable acidity, total chlorophyll, carotenoids, lycopene, anthocyanins, phosphorus, potassium, sulfur, copper, and manganese were not affected by eCO2. Furthermore, we propose several approaches to improving vegetable quality based on the interaction of eCO2 with various factors, including species, cultivars, CO2 levels, growth stages, light, O3 stress, nutrient, and salinity. Finally, we present a summary of the eCO2 impact on the quality of three widely cultivated crops, namely, lettuce, tomato, and potato.

Five kinds of greenhouse vegetables (eggplant, loofah, tomato, cucumber and pepper) were selected in summer uprooting stage from greenhouse in Shouguang area, Shandong Province. Total nitrogen, ammonium nitrogen, nitrate nitrogen, available phosphorus, available potassium, organic matter content and pH, EC value of three soil layers were measured, respectively. The results showed that the total nitrogen, ammonium nitrogen, nitrate nitrogen, available phosphorus and available potassium in the soil were mainly accumulated in the upper soil, which made the soil acidification trend, because diiferent farmers adopted different cultivation practices for diferent greenhouse vegetables in Shouguang region, but there was no significant effect on soil EC value. The input of ammonium nitrogen and nitrate nitrogen and other related fertilizers to greenhouse cucumber was higher than that of other greenhouse vegetables, but the amount of available potassium fertilizer and organic matter input to greenhouse tomato under diferent cultivation practices was lower than other greenhouse vegetables. In Shouguang area, the input of organic matter into greenhouse vegetables should be increased by increasing the proportion of manure input to increase the content of soil organic carbon, so as to achieve the balance of carbon and nitrogen ratio, and to provide a scientific basis for the establishment of an evaluation system for the environmental benefits brought about by chemical fertilizer reduction in greenhouse vegetables in Shouguang area. [ABSTRACT FROM AUTHOR]

Elevated atmospheric CO2 (eCO2) enhances the yield of vegetables and could also affect their nutritional quality. We conducted a meta-analysis using 57 articles consisting of 1,015 observations and found that eCO2 increased the concentrations of fructose, glucose, total soluble sugar, total antioxidant capacity, total phenols, total flavonoids, ascorbic acid, and calcium in the edible part of vegetables by 14.2%, 13.2%, 17.5%, 59.0%, 8.9%, 45.5%, 9.5%, and 8.2%, respectively, but decreased the concentrations of protein, nitrate, magnesium, iron, and zinc by 9.5%, 18.0%, 9.2%, 16.0%, and 9.4%. The concentrations of titratable acidity, total chlorophyll, carotenoids, lycopene, anthocyanins, phosphorus, potassium, sulfur, copper, and manganese were not affected by eCO2. Furthermore, we propose several approaches to improving vegetable quality based on the interaction of eCO2 with various factors, including species, cultivars, CO2 levels, growth stages, light, O3 stress, nutrient, and salinity. Finally, we present a summary of the eCO2 impact on the quality of three widely cultivated crops, namely, lettuce, tomato, and potato. [ABSTRACT FROM AUTHOR]

Abstract: Biological control is widespread in management of greenhouse sweet pepper crops. Several species of predatory mites, bugs, and parasitoids are used against a wide range of pest species. However, biological control of particular pests like aphids, caterpillars, and the tobacco whitefly, Bemisia tabaci Gennadius, remains problematic. Macrolophus pygmaeus Rambur (Hemiptera: Miridae) is a generalist predatory bug which is used on a large scale in Western European tomato greenhouses. It has already been demonstrated that M. pygmaeus is a valuable biocontrol option in sweet pepper crops, but it has yet to find its way into common practice. Macrolophus pygmaeus should be introduced at the start of the growing season and determining an optimal release strategy is a key step in this process. In tomato crops, M. pygmaeus requires supplemental food releases to reach sufficient population numbers and dispersal levels. In this study, the need for food supplementation in sweet pepper is investigated. Three strategies were tested: (1) no food supplementation, (2) local food supplementation, and (3) full field food supplementation. Both population numbers and dispersal rates of the second generation were higher under the third strategy. Macrolophus pygmaeus oviposits near food sources, therefore dispersal rates are higher when food is more spread out. Pest control was achieved in all treatments, but faster and at lower pest levels under the full field strategy. [ABSTRACT FROM AUTHOR]

A rapid, sensitive and effective supercritical fluid chromatographic-tandem mass spectrometry (SFC-MS/MS) method was developed to analyze thiacloprid for the first time. The SFC-MS/MS conditions were optimized with the ultra-performance convergence chromatography (UPC 2 ) BEH column (100 mm × 3.0 mm, 1.7 μm particle size) and thiacloprid was eluted at 1.22 min in gradient mode with CO 2 /methanol as mobile phase. The 0.1% formic acid in methanol ( v / v ) was used as postcolumn compensation solution to improve sensitivity. The ABPR pressure, flow rate of mobile phase and flow rate of compensation pump were set at 1800 psi, 1.8 mL/min, and 0.1 mL/min, respectively. The average recoveries of thiacloprid in soil at four spiking levels (5, 10, 100, 1000 μg/kg) ranged between 78.8% and 107.1% with relative standard deviations (RSDs) lower than 12.2% and the limit of quantitation (LOQ) was 5 μg/kg. The proposed method can distinctly improve the analysis efficiency by 2–12 times and reduce the solvent consumption by 5%–95% compared with reported methods. It was applied to investigate the dissipation rates of thiacloprid in greenhouse vegetables and soil under different application modes. The half-lives of thiacloprid in cucumber and soil were 9.55–20.44 days and 3.74–9.14 days separately under different application modes, 10.60 days in tomato under foliar spraying. The residues in vegetables under root irrigation were all less than that under foliar spraying. The results could offer useful data for risk assessment of thiacloprid in agricultural production. [ABSTRACT FROM AUTHOR]

Lettuce is a cool season vegetable often produced in greenhouses and other protective structures to meet market demands. Greenhouses are being increasingly adopted in warm climate zones where excessive heat often leads to physiological disorders of lettuce, such as tipburn and premature bolting. Greenhouse lettuce growers in warm climates need cultivar recommendations that can help improve production without ignoring marketability. In the current study, eighteen lettuce cultivars were grown in deep water culture and evaluated for growth, bolting, and tipburn in a greenhouse in Auburn, AL, starting on 30 June and 19 August 2016. Based on the severity of bolting and tipburn, nine cultivars were then selected and evaluated on 17 November 2016 for sensory attributes and marketability by 50 untrained consumer panelists. Cultivars ‘Adriana’, ‘Aerostar’, ‘Monte Carlo’, ‘Nevada’, ‘Parris Island’, ‘Salvius’, ‘Skyphos’, and ‘Sparx’ were selected as having higher heat tolerance than cultivars ‘Bambi’, ‘Buttercrunch’ ‘Coastal Star’, ‘Flashy Trout Back’, ‘Green Forest’, ‘Green Towers’, ‘Jericho’, ‘Magenta’, and ‘Truchas’. Higher crispness, lower bitterness, higher overall texture, and higher overall flavor each correlated to higher marketability, regardless of cultivar, but the strongest predictor of marketability was overall flavor. Overall flavor and overall texture were more strongly correlated to marketability than bitterness and crispness, respectively, suggesting that broader sensory categories may better capture human sensory perceptions of lettuce than narrower categories. Cultivars ‘Aerostar’, ‘Monte Carlo’, ‘Nevada’, ‘Parris Island’, ‘Rex’, ‘Salvius’, and ‘Sparx’ performed well in a hot greenhouse and were preferred by consumers. This step-wise experiment could be an adaptable tool for determining highest performing cultivars under any given production constraint, without ignoring marketability.

This paper presents a novel image processing method using color information and region growing for segmenting greenhouse vegetable foliar disease spots images captured under real field conditions. Disease images captured under real field conditions are suffering from uneven illumination and complicated background, which is a big challenge to achieve robust disease spots segmentation. A disease spots segmentation method consisting of two pipelined procedures is proposed in this paper. Firstly a comprehensive color feature and its detection method are presented. The comprehensive color feature (CCF) consists of three color components, Excess Red Index ( ExR ), H component of HSV color space and b ∗ component of L ∗ a ∗ b ∗ color space, which implements powerful discrimination of disease spots and clutter background. Then an interactive region growing method based on the CCF map is used to achieve disease spots segmentation from clutter background. To evaluate the robustness and accuracy, the proposed segmentation method is assessed by cucumber downy mildew images. Results show that the proposed method can achieve accurate and robust segmentation under real field conditions. [ABSTRACT FROM AUTHOR]

This study reports the determination of trace essential (Co, Cr, Cu, Se, and Zn) and toxic (Al, As, Cd, Hg, and Pb) elements in greenhouse tomatoes, peppers, and cucumbers from supermarkets of Seoul, Busan, Gangneung, Daegu, Daejeon, and Gwangju, South Korea using inductively coupled plasma mass spectrometry, inductively coupled plasma optical emission spectroscopy, and direct mercury analysis. The methods were validated by linearity, limits of detection and quantification, precision, accuracy, and recovery measurements that provided satisfactory results in all cases. Among the essential trace elements, Zn was found to have the highest concentrations (0.84–2.5 mg/kg) followed by Cu (0.21–0.62 mg/kg) and Cr (0.01–0.06 mg/kg). The mean concentrations (mg/kg) of the toxic elements were in the order Al > Pb > As > Cd > Hg for tomatoes and cucumbers and Al > Pb > Cd > As > Hg for peppers; all were below the permissible limits set by World Health Organization for human consumption. The estimated dietary intake, target hazard quotients (THQs), and hazard indices of the samples were within safe levels. The combined THQ values for the toxic elements in the vegetables were from 0.002 to 0.012 with significant contribution from arsenic, aluminum, cadmium, and mercury. The results of this study show that trace and toxic elements in the analyzed vegetables do not impose any serious health harmful effects for the population upon consumption. [ABSTRACT FROM AUTHOR]

Research reported in this paper aims to improve the identification of greenhouse vegetable diseases based on the greenhouse monitoring video. It presents a method that combines the visual saliency and online clustering to extract the key frame from greenhouse vegetables monitoring video. Firstly X 2 histograms are used to measure the similarity of each frame to the first frame, which eliminates the meaningless frames and improve data processing efficiency and costs. Then, all frames will be converted to HSV color space and a saliency map of each frame is generated based on H component value and S component value. According to the saliency map, the salient region can be obtained. During the process of extracting the salient region, there is a possibility that the information of disease spots is lost. Therefore, morphological method would be utilized to restore the lost information. Finally, online clustering is performed to classify the salient regions into different clusters, and mean pixels value is used to select the key frames. The results indicate that this method can obtain information of entire leaf area of vegetables and extract the key frame effectively. [ABSTRACT FROM AUTHOR]

Abstract: Heavy metal accumulation in vegetables is a growing concern for public health. Limited studies have elucidated the heavy metal accumulation characteristics and health risk of different vegetables produced in different facilities such as greenhouses and open-air fields and under different management modes such as harmless and organic. Given the concern over the aforementioned factors related to heavy metal accumulation, this study selected four typical greenhouse vegetable production bases, short-term harmless greenhouse vegetable base (SHGVB), middle-term harmless greenhouse vegetable base (MHGVB), long-term harmless greenhouse vegetable base (LHGVB), and organic greenhouse vegetable base (OGVB), in Nanjing City, China to study heavy metal accumulation in different vegetables and their associated health risks. Results showed that soils and vegetables from SHGVB and OGVB apparently accumulated fewer certain heavy metals than those from other bases, probably due to fewer planting years and special management, respectively. Greenhouse conditions significantly increased certain soil heavy metal concentrations relative to open-air conditions. However, greenhouse conditions did not significantly increase concentrations of As, Cd, Cu, Hg, and Zn in leaf vegetables. In fact, under greenhouse conditions, Pb accumulation was effectively reduced. The main source of soil heavy metals was the application of large amounts of low-grade fertilizer. There was larger health risk for producers′ children to consume vegetables from the three harmless vegetable bases than those of residents′ children. The hazard index (HI) over a large area exceeded 1 for these two kinds of children in the MHGVB and LHGVB. There was also a slight risk in the SHGVB for producers′ children solely. However, the HI of the whole area of the OGVB for two kinds of children was below 1, suggesting low risk of heavy metal exposure through the food chain. Notably, the contribution rate of Cu and Zn to the HI were high in the four bases, yet current Chinese standards provide no limit for the concentrations of Cu and Zn; thus a potential health risk concerning these metals exists. [Copyright &y& Elsevier]

The impacts of nitrogen (N) application rates on soil nitrate, electrical conductivity (EC), pH, soil N2O emission, tomato yield and fruit quality were investigated in a 20-yr vegetable field experiment under greenhouse cultivation in Northeast China. The treatments included no N control (N0), the recommended N rate (N1; mean annual 300 kg/ha) and the commonly used N rate by farmers (N2; mean annual 600 kg/ha). Soil nitrate content and EC increased significantly to 120 cm depth with increasing rates of applied N. An opposite trend was found for soil pH within the upper 20 cm. Cumulative N2O emission and maximum N2O emission rates both increased significantly with increasing N rates. Tomato yield increased significantly from the N0 to N1 rate, but remained constant from the N1 to N2 one. Nitrate concentration in tomatoes also increased significantly with N rates. A contrasting trend was found for soluble sugar and organic acid concentrations. The results indicate that the commonly used N2 rate is excessive and causes adverse effects on tomato quality and on the environment. The recommended N1 rate is optimal for sustainable greenhouse vegetable production. In greenhouses, daily soil N2O emission rates are strongly influenced by N application and fluctuate with irrigation frequency and the incidence of wetting/drying cycles. [ABSTRACT FROM AUTHOR]

Abstract: The energy consumption and fossil CO2 emissions from the Canadian vegetable greenhouse industry were assessed using greenhouse statistics from 2002 to 2007. The fossil CO2 emissions were compared to the fossil CO2 emitted during transport of an equal weight of food by truck and by airplane from two horticultural production centers in the southern USA to four locations in Canada. The calculations in this paper for Canadian greenhouse energy use for heating were verified against farm energy use survey data collected from greenhouse operators in 1996. Allowing for extrapolations to 1996 from the 2002 to 2007 period, the survey data were underestimated by 12%. Since the survey data were not corrected for possible household energy use by greenhouse operators, some underestimation in the heat energy calculations was expected. The fossil CO2 emissions from Canadian greenhouses were 0.35Tg. This estimate is about twice as high as the diesel fuel CO2 emissions required to truck the same weight of vegetables from south to north, but only slightly less than half the CO2 emissions to ship the same vegetables by air. Quebec greenhouse crops had the lowest CO2 emission intensity and the least difference with trucking CO2 emissions, while BC greenhouse crops had the highest CO2 emission intensity and the most difference with trucking CO2 emissions. The study revealed some potential CO2 mitigation practices including alternative fuels such as straw pellets or wood chips, non-recycle-able combustible urban waste and biogas from city waste treatment facilities or manure storage systems. Mitigation of heat energy loss could involve insulating heating lines within greenhouses and doorway designs that minimize the time and area open to the outside air. In order to reduce the CO2 emission intensity, research should aim at a higher ratio of yield to fossil energy use, rather than simply trying to maximize greenhouse yields. [Copyright &y& Elsevier]

The etiology of internal fruit rot of greenhouse-grown sweet pepper, caused by the fungus Fusarium lactis, was investigated during anthesis and fruit development using stereo, fluorescence and scanning electron microscopy. Proliferation of fungal mycelium was observed on the surface of the stigma one day after inoculation (DAI). Mycelial growth was also visible in the transmitting tissues of the style and inside the ovary at 5 and 6 DAI. When externally symptomless sweet pepper fruits were sectioned 45 DAI, typical internal fruit rot symptoms were observed. Culturing of hyphal-like strands and ovules from inoculated flowers on potato dextrose agar (PDA) confirmed the presence of F. lactis. Similarly, symptomless seeds from infected fruit also yielded colonies of the fungus on PDA. These findings support the hypothesis that internal fruit rot of greenhouse sweet pepper caused by F. lactis is initiated through the infection of the stigma and style during anthesis. Moreover, symptomless seed infection may contribute to disease spread between greenhouses, although further work is needed to understand how F. lactis becomes established and spreads from infected seeds to flowers. [ABSTRACT FROM AUTHOR]

The objective of this investigation was to determine nutritional and performance quality indices of greenhouse cucumber (Cucumis sativa L.) in relationship with fruit nutrient concentrations. Fruit firmness showed a positive correlation with fruit calcium (Ca) concentration (r = 0.66; P < 0.01). Ascorbic acid and citric acid concentrations in the fruit were positively influenced by potassium (K) concentration. There was a negative correlation between the fruit pH and phosphorus (P) concentration (r = -0.54; P < 0.01). The greenish color intensity (-a) of the fruit skin was positively correlated (r = 0.58; P < 0.01) to the magnesium (Mg) concentration. On the other hand, the basic tint of color (H) was lower in the fruits with higher K concentration. The mean nitrate concentration in the greenhouse cucumber was about 2.5 times higher than the World Health Organization (WHO) standard limit that shows high potential health risks. Potassium was the most important effective element on cucumber quality. [ABSTRACT FROM AUTHOR]

Elevated heavy metal (HM) concentrations in vegetables may pose serious health risks to humans. There is limited information on health risks associated with HM contaminants in greenhouse vegetables. The objective of this study was to estimate the health risks of Pb, Cd, Ni, and Cr via consumption of greenhouse cucumbers and bell peppers produced in Iran using the total non-cancer hazard quotient (THQ) and cancer risk assessment estimates. Cadmium, Pb, Ni, and Cr concentrations in the vegetables varied from < 0.02 to 0.05, 0.19 to 0.64, 0.16 to 0.20 and 0.07 to 0.13 μg g-1, respectively. Individual metal THQ values indicate the relative absence of non-cancer health effects associated with intake of a single metal through consumption of either cucumbers or bell peppers. The THQ for all population groups via consumption of greenhouse cucumbers and bell peppers was smaller than 1.0, which shows low possibility of any obvious risk. The result showed that Cd is the major risk contributor for the consumers. The cancer risk assessment for Pb for Qom adult populations groups via consumption of cucumbers and bell peppers was greater than 1 × 10-6. High Pb and Cd concentration in the greenhouse vegetables is an important concern that has to be considered. [ABSTRACT FROM AUTHOR]

Abstract: Effects of excessive fertilizer and manure applications on the soil environment were compared in greenhouse vegetable systems shifted from wheat–maize rotations 5–15years previously and in wheat–maize rotations. N, P and K surpluses to the greenhouses were 4328, 1337 and 1466kgha−1 year−1, respectively compared to 346, 65 and −163kgha−1 year−1 to wheat–maize fields. Subsequently, substantial mineral N and available P and K accumulated in the soil and leaching occurred down the soil profile in the greenhouses. Soil pH under vegetables was significantly lower than in the wheat–maize fields, while the EC was significantly higher in the vegetable soils. The mean Cd concentration in the vegetable soils was 2.8 times that in the wheat–maize rotations. Due to excessive fertilizer application in greenhouse vegetable production in northeast China, excessive salt and nitrate concentrations may accumulate and soil quality may deteriorate faster than in conventional wheat–maize rotations. [Copyright &y& Elsevier]

Abstract: The annual nitrogen (N) budget and groundwater nitrate-N concentrations were studied in the field in three major intensive cropping systems in Shandong province, north China. In the greenhouse vegetable systems the annual N inputs from fertilizers, manures and irrigation water were 1358, 1881 and 402kgNha−1 on average, representing 2.5, 37.5 and 83.8 times the corresponding values in wheat (Triticum aestivum L.)–maize (Zea mays L.) rotations and 2.1, 10.4 and 68.2 times the values in apple (Malus pumila Mill.) orchards. The N surplus values were 349, 3327 and 746kgNha−1, with residual soil nitrate-N after harvest amounting to 221–275, 1173 and 613kgNha−1 in the top 90cm of the soil profile and 213–242, 1032 and 976kgNha−1 at 90–180cm depth in wheat–maize, greenhouse vegetable and orchard systems, respectively. Nitrate leaching was evident in all three cropping systems and the groundwater in shallow wells (<15m depth) was heavily contaminated in the greenhouse vegetable production area, where total N inputs were much higher than crop requirements and the excessive fertilizer N inputs were only about 40% of total N inputs. [Copyright &y& Elsevier]

Agronomic biofortification of horticultural crops using plant growth-promoting rhizobacteria (PGPR) under crop residue incorporation systems remains largely underexploited. Bacillus subtilis (B1), Bacillus laterosporus (B2), or Bacillus amyloliquefaciens (B3) was inoculated on soil containing chili residue, while chili residue without PGPR (NP) served as the control. Two hybrid long cayenne peppers, succeeding a leaf mustard crop were used in the intensive cultivation study. Net photosynthesis, leaf stomatal conductance, transpiration rate, photosynthetic water use efficiency, shoot and root biomass, and fruit yield were evaluated. Derivatives of folate, minerals, and nitrate contents in the pepper fruits were also assessed. B1 elicited higher net photosynthesis and photosynthetic water use efficiency, while B2 and B3 had higher transpiration rates than B1 and NP. B1 and B3 resulted in 27–36% increase in pepper fruit yield compared to other treatments, whereas B3 produced 24–27.5% and 21.9–27.2% higher 5-methyltetrahydrofolate and total folate contents, respectively, compared to B1 and NP. However, chili residue without PGPR inoculation improved fruit calcium, magnesium, and potassium contents than the inoculated treatments. 'Xin Xian La 8 F1' cultivar had higher yield and plant biomass, fruit potassium, total soluble solids, and total folate contents compared to 'La Gao F1.' Agronomic biofortification through the synergy of Bacillus amyloliquefaciens and chili residue produced better yield and folate contents with a trade-off in the mineral contents of the greenhouse-grown long cayenne pepper. [ABSTRACT FROM AUTHOR]