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Quantitative evaluation of the effects of diverse greenhouse vegetable production systems (GVPS) on vegetable yield, soil water consumption, and nitrogen (N) fates could provide a scientific basis for identifying optimum water and fertilizer management practices for GVPS. This research was conducted from 2013 to 2015 in a greenhouse vegetable field in Quzhou County, North China. Three production systems were designed: conventional (CON), integrated (INT), and organic (ORG) systems. The WHCNS-Veg model was employed for simulating vegetable growth, water dynamics, and fates of N, as well as water and N use efficiencies (WUE and NUE) for four continuous growing seasons. The simulation results revealed that nitrate leaching and gaseous N emissions constituted the predominant N loss within GVPS, which separately accounted for 11.5–59.4% and 6.0–21.1% of the N outputs. The order of vegetable yield, N uptake, WUE, and NUE under different production systems was ORG > INT > CON, while the order of nitrate leaching and gaseous N loss was CON > INT > ORG. Compared to CON, ORG exhibited a significant increase in yield, N uptake, WUE, and NUE by 24.6%, 24.2%, 26.1%, and 89.7%, respectively, alongside notable reductions in nitrate leaching and gaseous N loss by 67.7% and 63.2%, respectively. The ORG system should be recommended to local farmers. [ABSTRACT FROM AUTHOR]

Objective: Non-typhoidal Salmonella (NTS) is a major cause of human salmonellosis globally. Food animals are major NTS reservoirs. An increase in antimicrobial resistance (AMR) in foodborne NTS has led to clinical treatment failures. Here, to examine the prevalence and perform characterization of foodborne NTS with AMR in China, we tested the antimicrobial susceptibility of 1,256 NTS isolates cultured from retail foods in 2020 in China. Methods: The antimicrobial susceptibility of 26 antimicrobial agents representing 12 classes was evaluated with the broth-microdilution method; the presence of ten mcr genes was screened with multi-PCR. The complete closed genomes of mcr-gene-carrying isolates were generated by hybrid assembly through whole genome sequencing on both the PacBio and Illumina platforms. Genomic features and genetic environments of the mcr-1 gene were analysed. Results: The overall drug resistance rate was 92.28%, and the multi-drug resistance (MDR) rate was 76.53%. A total of 341 AMR profiles were determined, and resistance was highest to nalidixic acid (63.38%). Among 887 NTS isolates with MDR, 232 showed co-resistance to cefotaxime and ciprofloxacin, and 25 were resistant to ten classes of antimicrobial agents. The resistance of NTS isolated from different regions varied. Isolates from raw chicken sources most frequently showed resistance. Four NTS carried the mcr-1 gene and represented four different serotypes. Four mcr-1 gene-bearing plasmids from the four Salmonella isolates were classified into two replicon types (IncI2 and IncHI2A). Two mcr-1 genes in IncI2 type plasmids were found to be located between a PAP2 family protein-encoding gene and a relaxaseencoding gene, whereas the other two mcr-1 gene structures in IncHI2A type plasmids showed variations in the presence of insertion sequences. Conclusion: Our data demonstrated severe AMR among foodborne NTS isolated from food in China, thus highlighting the importance of antimicrobial susceptibility surveillance to decrease the spread of AMR, particularly to critical drugs in human medicine. [ABSTRACT FROM AUTHOR]

The global outbreak of the COVID-19 pandemic has slowed down international investment and trade, and partially disrupted the global supply chain. This paper provides an overview of the findings in 80 scholarly articles from recent years, comprehensively summarises and analyzes the research on international capital flows and global value chain（GVC）reconstruction, and deeply reveals the impact of COVID-19 on OFDI, the change of OFDI performance before and after the pandemic and factors that may accelerate GVC reconstruction in the future. We identify research gaps in a combination of OFDI and GVC reconstruction at both the macro and micro level and suggest several future research topics such as political risk and bilateral relations factors, the role of China in OFDI and GVC dynamics, network and OFDI performance, network characteristics of GVC reconstruction, OFDI and GVC reconstruction. [ABSTRACT FROM AUTHOR]

Subsurface organic ameliorant plus polyethylene mulching is a novel strategy for saline soil improvement and utilization in China. However, little is known about how this strategy impacts soil organic carbon (SOC) both directly (carbon input) and indirectly (soil aggregates protection and microbial regulation). Therefore, a field experiment was arranged and sampled after 3 years, including four treatments, i.e., no ameliorant with and without polyethylene mulching, and subsurface (10–30 cm soil depth) organic ameliorant with and without polyethylene mulching. Subsurface organic ameliorant raised the SOC content in the 0–40 cm by 70% and 90% with and without mulching, respectively. Subsurface organic ameliorant converted the major aggregation size from <0.053 to 0.25–2 mm, indicating that both direct carbon (C) input and indirect soil aggregates protection contributed to the increase in SOC content. In contrast, polyethylene mulching reduced the SOC content by 16% and 6% with and without organic ameliorant respectively. This was due to lower fungal diversity by 9%–14% and supported by the positive effect from fungal diversity to SOC. Further, the subsurface organic ameliorant plus polyethylene mulching increased SOC by 61% through direct C input, indirect soil aggregates protection and microbial regulation. Meanwhile, the contribution of physical protection standardized total effect (STE) = 0.223–0.294] was higher than microbial regulation (STE = 0.040–0.162) according to a structural equation model. Consequently, subsurface organic ameliorant plus polyethylene mulching represents a feasible agricultural practice to increase the SOC content for saline soil amelioration. [ABSTRACT FROM AUTHOR]

Prolonged and intricate trade frictions existed between China and the US, which grew more and more intense during Trump's presidency. Indicators of US anti-dumping policies against China of Temporary Trade Barrier Database (TTBD) from 2000 to 2014 and the global value chains indexes proposed by Wang et al. were adopted in this article to explore the impacts of such policies on China's manufacturing global value chains status. The results showed that US anti-dumping against China policies shortened the backward linkage based production length at a faster speed, which resulted in a relatively upstream movement of the production line position in China. Ultimately, it enhanced the status of Chinese manufacturing in the global value chains. Therefore, China should continue the open-up policy and strengthen its interconnections with world economy to obtain a broader and more sustainable growing prospect. [ABSTRACT FROM AUTHOR]

The increasing demand for ecosystem services in regional development has presented significant challenges to environmental sustainability. To alleviate environmental pressure, it is crucial to employ the provincial ecological footprint to gauge regional ecological pressure and research the determinants that contribute to reducing environmental pressure. This underscores the significance of examining and addressing the intricate relationships between ecological resources and regional development. While prior studies often focus on national data, provincial ecological footprints have been relatively ignored. Moreover, scant research exists on the influence of variables such as resource rents and industrial structures. This study employs the ecological footprint model to assess the per capita ecological footprint of Chinese provinces from 1990 to 2020, intending to gauge escalating ecological pressures and pinpoint their drivers. We use spatial panel data analysis to investigate the association among economic growth, natural resource rents, industrial structures and ecological footprint. Leveraging spatial weight matrices, we detected provincial footprint spatial autocorrelation and further analyzed it using the spatial Durbin model. Results underscore that economic growth profoundly shapes the ecological footprint, but an explicit Environmental Kuznets Curve remains elusive. Both natural resource rents and industrial shifts considerably influence the ecological footprint. Distinguishing from earlier non-spatial studies, our research merges spatial panel data analysis, emphasizing the regulatory role of juxtaposing natural resource rents with industrial structure adjustment can decrease the impact of economic growth on the ecological footprint. Advocating robust policies that favor renewables over non-renewables is pivotal, emphasizing the imperative for rigorous environmental standards in sectors shifting to renewables. [ABSTRACT FROM AUTHOR]

[Display omitted] • Soil organic and inorganic C content were higher under organic ameliorants. • Humic acid plus manure alleviated microbial N and P limitation by reducing soil electric conductance. • Humic acid plus manure promoted the positive regulation of soil organic C on inorganic C. • Electric conductance and microbial resource limitation were the main factors affecting soil C content. • Humic acid plus manure is more recommended in saline soil. Fertilization strategies have been widely studied as an effective strategy to improve the structure and fertility of saline soils. However, the effect of the combination of different organic ameliorants on the soil carbon (C) pool is still not clear. We conducted a two-year field experiment to investigate the influences of organic ameliorants on soil organic C (SOC) and inorganic C (SIC) stocks, and enzymatic stoichiometry for both top and subsoil (i.e., 0–20 cm and 20–40 cm) in the semi-arid saline region of Western China. Compared to chemical fertilizer (CK) soils, the content and stock of total C and SOC at 0–40 cm soil layer under organic ameliorant (OM), humus acid plus OM (HA + OM), and biofertilizer plus OM (B + OM) were 9–40% higher, whilst the content and stock of SIC at 0–40 cm soil layer under HA + OM were 18% higher after two years. In addition, soil microorganisms were generally limited by phosphorus (P), and HA + OM reduced microbial P and nitrogen (N) limitations after two years application. Structural equation modeling showed that reduced microbial N and P limitation under HA + OM was mainly directly driven by the decrease in electrical conductivity (EC) content. Redundancy analysis and correlation analysis further confirmed that soil EC and microbial resource limitation were the main factors affecting soil C content. Furthermore, HA + OM promoted the positive regulation of SOC on SIC, which facilitated the formation of SIC content. The higher accumulation of SOC and SIC content under HA + OM were both beneficial to the enhancement of the total C stock in saline soil. Overall, our results provided an effective regime to improve the soil saline and microbial environments, and increase the potential for rapid enhancement of the C stock of saline soil in Northwest China. [ABSTRACT FROM AUTHOR]

Straw deep returning as an interlayer is a novel practice to enhance soil carbon and nutrients. However, the impact of applying various amounts of straw as an interlayer on soil quality still remain unclear in the saline soil. Therefore, a field experiment was carried out over four years (2015–2018) in Hetao Irrigation District, China. The aim was to evaluate the impact of four straw interlayer rates (i.e., 0, 6, 12, and 18 Mg ha−1) applied at 40 cm depth on soil quality index (SQI) and its relationship to sunflower yield in saline soil. Our results showed that, in comparison to no straw interlayer (CK), straw interlayers applied at rates of 6, 12, and 18 Mg ha−1 improved SQI on average by 2.0, 2.7, and 3.0 times in four years, respectively (p < 0.05). This suggested that straw deep returning as an interlayer improved SQI, especially for middle and high amounts (12 and 18 Mg ha−1). Partial least squares path model (PLSPM) illustrated that the improvement of SQI was due to the high-moisture and low-salt environment created by straw interlayer in the early two years (2015–2016), while the higher soil nutrients released from straw decomposition in the subsequent years (2017–2018). The improvement of SQI contributed to sunflower yield, which was related to the decrease of soil salinity, the increase of soil moisture, soil organic carbon (SOC), total nitrogen (TN), and available nutrients under straw interlayers. The sunflower yield was increased by 8.7–13.4% under straw interlayers (p < 0.05), following the order of 18 = 12 > 6 >0 Mg ha−1. The greater increment of yield was detected during the initial phase of burying straw interlayers, which indicated that straw as an interlayer played a more important role than nutrient supply from straw decomposition. The findings highlighted that appropriate straw return amount (i.e., 12 Mg ha−1) as an interlayer is an economic practice to benefit soil quality and crop yield synchronously in salt-affected soils. [Display omitted] • Straw deep returning as interlayer improved soil quality. • Great soil quality was due to the high moisture and low salt in the first two years. • Great soil quality was due to the higher soil nutrients in the last two years. • The improvement of soil quality significantly increased sunflower yield. [ABSTRACT FROM AUTHOR]

An outbreak of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread worldwide. In this major outbreak, women are a special group, especially pregnant patients. Many problems faced by clinicians are still unclear and need to be solved. As the largest obstetrics and gynecology hospital in North China, here we summarize the diagnosis and treatment process and key points of obstetrics and gynecology patients in our hospital during the period of the COVID-19 pandemic, hoping to provide available information to inform care of obstetrics and gynecology patients. [ABSTRACT FROM AUTHOR]

• The N 2 O emissions sub-models from DAYCENT 4.5 were coupled with WHCNS-Veg model. • Soil hydraulic parameters had a relatively higher sensitivity on N 2 O emissions. • The model performed well in modeling N 2 O emissions under different management systems. • The N 2 O emissions in spring-summer season were far higher than the autumn-winter season. • Substituting organic manure for chemical fertilizer could reduce the N 2 O emissions in greenhouse. Quantifying greenhouse gas emissions from greenhouse vegetable production systems (GVPS) is helpful to direct carbon sequestration and greenhouse gas emissions reduction. The objectives of this study were to (i) evaluate the performance of the improved WHCNS-Veg model (soil Water Heat Carbon Nitrogen Simulation for Vegetable) in simulating nitrous oxide (N 2 O) emissions under different GVPS and (ii) analyze the impact of different management systems on N 2 O emissions from the GVPS. Greenhouse vegetable experiments were carried out under different management systems, including conventional (CON), integrated (INT) and organic (ORG), in Quzhou County, Hebei province from 2013 to 2015. Field observations of soil water content, soil nitrate concentration and N 2 O emissions were used to calibrate and validate the WHCNS-Veg model. The sensitivity analysis results showed that the effects of soil hydraulic parameters on N 2 O emissions were higher than those of N transformation and vegetable genetic parameters. The improved WHCNS-Veg model simulated soil water content, soil nitrate concentration and N 2 O emissions well under different GVPS. The average N 2 O emissions in the spring-summer season (16.3 kg N ha−1) were about 2.5 times higher than the autumn-winter season (6.4 kg N ha−1). Among the four seasons, the average N 2 O emissions of CON, ORG and INT were 13.5, 11.3 and 9.3 kg N ha−1, respectively, accounting for 1.4–1.7% of the total fertilizer input. The N 2 O emissions of the INT and ORG systems were 31.1% and 16.3% lower than the CON treatment, respectively. The results indicated that the improved WHCNS-Veg model can be used to simulate and analyze N 2 O emissions under different management systems and substituting organic manure for chemical fertilizer could effectively reduce the N 2 O emissions in the GVPS. [Display omitted] [ABSTRACT FROM AUTHOR]

Limited water resources have severely restricted saline soil amelioration and utilization in the Hetao irrigated area, China. Burying straw interlayer is an effective management for salt-affected soil amelioration. However, little is known whether the straw interlayer could boost soil fertility and improve bacterial community, while reducing irrigation water consumption by 10% in the third and fourth years after application. Therefore, the legacy effect of the combination of straw interlayer and irrigation water reduction was investigated following the three treatments: (i) no straw interlayer plus 100% irrigation (CK); (ii) straw interlayer plus 100% irrigation (SI+W100), and (iii) straw interlayer plus 90% irrigation (SI+W90). SI+W90 significantly increased 0–40 cm soil organic carbon (SOC) content and soil SOC/TN (C/N) ratio than CK by 12% and 13%, respectively. In addition, SI+W90 significantly decreased 0–40 cm soil total nitrogen (TN) and SOC contents by 10% and 8% respectively, but significantly increased 0–40 cm soil C/N ratio by 9%, compared to SI+W100. Furthermore, SI+W100 and SI+W90 significantly increased the relative abundance of Proteobacteria , Bacteroidetes , and Nitrospirae than that of CK, while SI+W90 significantly decreased the relative abundance of Acidobacteria compared to SI+W100, and these bacterial phyla were significantly correlated with 0–40 cm SOC content. Notably, there was no significant correlation between crop yield and soil parameters in 2018 with the relatively low yield, while crop yield was significantly correlated with 0–20 cm SOC content and the relative abundance of Proteobacteria and Firmicutes in 2019 with relatively high yield. These results indicated that both soil fertility and certain bacterial phyla may contribute to yield variation. Therefore, SI+W90 maintained crop yield in the two years. In conclusion, the combination of straw interlayer and irrigation water reduction may be more recommended for agricultural sustainable development under the condition of limited irrigation water supply in the arid and salt-affected regions. [Display omitted] • 100% irrigation with buried straw increased the TN relative to 90% irrigation. • Buried straw with 100% and 90% irrigation considerably increased SOC and affected bacterial community. • 90% irrigation with buried straw was more conducive to increase soil C/N ratio. • 90% irrigation with buried straw was suggested in arid saline soil. [ABSTRACT FROM AUTHOR]

• Soil water significantly decreased with rates of buried straw during the later stage of sunflower. • Salt leaching flux increased with increases in thickness of buried straw. • Adoption of straw barrier affected saturated water conductivity and porosity among layers. • As the years went by, the thicker straw layer increased the upward mobility of salt. • The 5 cm thickness straw layer is more practical for field work in dry saline soil. Salt stress severely constrains crop productivity in arid lands of the world. Burying straw at the 40 cm soil depth plus plastic film mulching could mitigate root zone salinity, but little is known about how the thickness of buried straw affects soil water and salt transport. Therefore, a three-year field experiment was conducted from 2010 to 2013 to address this issue, with treatments including: compacted straw thickness of 3 cm (T3), 5 cm (T5), or 7 cm (T7) (corresponding to straw application at rates of 6, 12 and 18 t ha−1, respectively). In addition, a supplementary experiment, which included treatments of no buried straw layer (CK) and 5 cm of compacted straw layer thickness (t5) in the same micro-plot experiment, was carried out from 2014 to 2016 to identify soil pore structure and hydraulic parameters after three years of deep straw burial. Results showed that the initial soil water content increased with increasing thickness but significantly (P < 0.05) decreased in later periods. Soil salinity consistently decreased with increasing straw thickness, and T7 was most effective for improving salt leaching. However, the water and salt regulation under T5 gradually decreased mainly due to the change in saturated water conductivity and porosity among layers. After irrigation, the flux of salt leaching (FL) increased with straw thickness, and the FL under T7 significantly exceeded that under T3 by 105, 89 and 33% and that under T5 by 84, 66 and 33% in 2011, 2012 and 2013, respectively. The salt flux during evaporation under T7 was much higher (P < 0.05) than that under T3 and T5 by 92 and 10% in 2012 and 38, 44% in 2013. At harvest, salt storage within the soil consistently ranked as T3 > T5 > T7. Although T7 had the most pronounced effect on salt mitigation, it was difficult to implement under normal field conditions. Thus, for relatively good water infiltration, salt leaching and inhibition of salt return, straw buried to a thickness of 5 cm is recommended. [ABSTRACT FROM AUTHOR]

Organic cultivation has been promoted in recent years as a possible alternative to conventional cultivation in order to reduce environmental burdens and nonrenewable resource use. However, a comprehensive assessment of the sustainability of different vegetable cultivation modes is currently lacking. In this study, a combined use of economic analysis (ECA), emergy analysis (EMA), and lifecycle assessment (LCA) was conducted to evaluate the economic performance, resource use, and environmental impacts of three greenhouse eggplant production modes, namely conventional (CON), low-input (LOW), and organic (ORG) cultivation. ECA results showed that the economic profit and value to cost ratio of ORG increased by 14%–17% and 36%–41% compared with CON and LOW, respectively. EMA results showed that ORG had higher resource use efficiency. The unit emergy value and emergy sustainability index of ORG increased by 37%–49% and 45%–65% than those of CON and LOW, respectively. LCA results revealed lower potential environmental impacts for ORG, and its total potential environment impact index was 80%–91% lower than that of CON and LOW. These results showed that organic vegetable cultivation reduced resource and environmental costs while increasing farmers' income, which is the most sustainable vegetable production mode in the North China Plain. [ABSTRACT FROM AUTHOR]

This study aimed at assessing the occurrence of twelve mycotoxins, including deoxynivalenol (DON) and its derivatives, 3- and 15-acetyl-deoxynivalenol (3-ADON and 15-ADON), nivalenol (NIV), zearalenone (ZEN), fumonisins (FB 1 , FB 2 and FB 3) and aflatoxins (AFB 1 , AFB 2 , AFG 1 and AFG 2) in 338 unprocessed wheat samples harvested in 2018 from China by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). DON was found to be the most predominant and abundant mycotoxins followed by 3-ADON, 15-ADON, NIV, FB 1 , ZEN, FB 3 , FB 2 , AFB 1 , AFB 2 , AFG 2 and AFG 1. Samples from Hubei and Anhui provinces that situated the Yangtze River recorded a higher positive rate for Fusarium mycotoxins. The positive rate and average concentration of fumonisins in wheat samples are relatively low while the co-occurrence of fumonisins as well as DONs and its derivatives 3-ADON and 15-ADON, ZEN and/or NIV was found to be 37.6%. Moreover, compared with wheat samples in 2017, the combined levels of DON and its derivatives, 3-ADON and 15-ADON in wheat samples harvested in the year of 2018 is higher with the incidence of co-occurrence of DON + 3-ADON + 15-ADON significantly raised which may due to the increased precipitation weather conditions. These findings suggest the necessity of monitoring contamination of Fusarium mycotoxins and further raise concerns as to DON + 3-ADON + 15-ADON co-occurrence in wheat in China in order to protect consumers' health from the toxins exposure risks. • Twelve mycotoxins are detected in 338 wheat samples harvested in 2018 from China. • Deoxynivalenol (DON) is the most abundant toxin detected in wheat samples. • The incidence of co-occurrence of DON, 3-ADON and 15-ADON in 2018 is raised. • The incidence of co-occurrence of fumonisins with other Fusarium toxins is 37.6%. [ABSTRACT FROM AUTHOR]

A total of 769 wheat kernels collected from six provinces in China were analyzed for beauvericin (BEA) and four enniatins (ENNs), namely, ENA, ENA 1 , ENB and ENB 1 , using a solid phase extraction (SPE) technique with ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The results show that the predominant toxin was BEA, which had a maximum of 387.67 μg/kg and an average of 37.69 μg/kg. With regard to ENNs, the prevalence and average concentrations of ENB and ENB 1 were higher than those of ENA and ENA 1 . The geographical distribution of BEA and ENNs varied. Hubei and Shandong exhibited the highest and lowest positive rates of BEA and ENNs (13.46% and 87.5%, respectively). However, no significant difference was observed among these six provinces. There was a co-occurrence of BEA and ENNs, and 42.26% of samples were simultaneously detected with two or more toxins. Moreover, a significant linear correlation in concentrations was observed between the four ENN analogs ( r range: 0.75~0.96, p < 0.05). This survey reveals that the contamination and co-contamination of BEA and ENNs in Chinese wheat kernels were very common.

Hepatitis E virus (HEV) is a biological hazard that must be controlled and is a recognized etiological agent in viral hepatitis. This is a zoonotic virus and can be transmitted through the fecal-oral route. The pig is an important reservoir host of HEV, and is a source of contamination for the consumer after the consumption of raw or undercooked pork products. When detected, the most prevalent genotype of HEV in China is genotype 4 (denoted as HEV-4). To ensure the safety of this food of animal origin, we undertook a survey of HEV contamination in pig livers and pork samples available for sale, in retail outlets in selected cities in China. Viral RNA was purified from samples collected by lysing in Trizol followed by purification using trichloromethane and virus RNA extract kit. An additional step was applied to improve the recovery rate by adding RNase OUT when extracting virus RNA from pig livers, and the RNA productions were washed in 75% (v/v) ethanol to remove inhibitors. In total, 158 pig livers and 80 pork samples were procured and analyzed by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). After purification of total RNA from all samples taken and analyzed by RT-qPCR, a single pig liver was positive by this method for HEV. The positive rate was calculated as 0.63%. In this study, a single positive sample was detected. Considering the dietary habits of Chinese people, pork is a popular food that on occasion may be contaminated with HEV, thereby posing a threat to consumer health. Ongoing surveillance is required to assess the risk to human health arising from HEV-contaminated pork being offered for sale, at retail outlets, especially in the areas of China where pig production is practiced.

Genetic and physical maps are powerful tools to anchor fragmented draft genome assemblies generated from next-generation sequencing. Currently, two draft assemblies of Nelumbo nucifera, the genomes of 'China Antique' and 'Chinese Tai-zi', have been released. However, there is presently no information on how the sequences are assembled into chromosomes in N. nucifera. The lack of physical maps and inadequate resolution of available genetic maps hindered the assembly of N. nucifera chromosomes. Here, a linkage map of N. nucifera containing 2371 bin markers [217 577 single nucleotide polymorphisms (SNPs)] was constructed using restriction-site associated DNA sequencing data of 181 F 2 individuals and validated by adding 197 simple sequence repeat (SSR) markers. Additionally, a BioNano optical map covering 86.20% of the 'Chinese Tai-zi' genome was constructed. The draft assembly of 'Chinese Tai-zi' was improved based on the BioNano optical map, showing an increase of the scaffold N50 from 0.989 to 1.48 Mb. Using a combination of multiple maps, 97.9% of the scaffolds in the 'Chinese Tai-zi' draft assembly and 97.6% of the scaffolds in the 'China Antique' draft assembly were anchored into pseudo-chromosomes, and the centromere regions along the pseudo-chromosomes were identified. An evolutionary scenario was proposed to reach the modern N. nucifera karyotype from the seven ancestral eudicot chromosomes. The present study provides the highest-resolution linkage map, the optical map and chromosome level genome assemblies for N. nucifera, which are valuable for the breeding and cultivation of N. nucifera and future studies of comparative and evolutionary genomics in angiosperms., (© 2018 The Authors The Plant Journal © 2018 John Wiley & Sons Ltd and Society for Experimental Biology.)

Objective: To survey the fungi contamination of different feed ingredients in China., Methods: Soybean meal, cottonseed meal, wheat bran and distillers dried grains with soluble (DDGS) were collected from feed enterprises in different part of the country. Feed ingredient samples were diluted and inoculated and the key factors were screened which influenced the isolation., Results: Potato dextrose agar (containing chloramphenicol 0.1 g/L) and 10(-1) dilution were the optimum culture medium and dilution respectively. The range of fungi contamination was from 31% (DDGS) to 88% (wheat bran). The fungi contamination frequencies of feed ingredients varied from region to region, and varied from kind to kind. The contamination of Aspergillus flavus and Fusarium spp. were also different in the regions and sample types. The average contamination percentage of Aspergillus flavus (25%) is higher than Fusarium spp. (11%), and their contamination level is highest in northeast China and lowest in south China, wheat bran and cottonseed meal were the highest and DDGS was the lowest., Conclusion: The fungi contamination, including Aspergillus flavus and Fusarium spp. of feed ingredients all over the country should be pay more attention. It is recommended that prevention of feed ingredients from fungi contamination is needed.

Objective: To identify the aflatoxins contamination of corn in China., Methods: Aflatoxins B1, B2, G1 and G2 in 279 corn samples collected from 6 provinces or autonomous regions were determined by HPLC., Results: Aflatoxins were detected in 75.63% of 279 corn samples. The average concentration of positive samples was 44.04 microg/kg, with a range of 0.20 - 888.30 microg/kg. The positive rates of samples from Sichuan, Hubei, Guangxi, Henan, Guangdong and Jilin Provinces were 90.48%, 93.75%, 87.50%, 36.96%, 91.84% and 52.17% respectively, with an average concentration of 107.93, 70.98, 39.65, 8.06, 3.70 microg/kg, and 1.15 microg/kg respectively. AFB1 was detected more frequently and with higher levels than the other three aflatoxins, with a positive rate of 74.55% and an average concentration of 39.64 microg/kg. The positive rate of AFB2, AFG1 and AFG2 was 58.42%, 41.22% and 19.71% respectively, and the average concentration of them was 3.81, 3.47 and 0.51 microg/kg respectively., Conclusion: Corn samples collected from all six regions are contaminated widely with aflatoxins in various degrees. The contamination of aflatoxins in the South was more serious than that in the North of China. AFB1 is the prominent one among the four aflatoxins.