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Simple Summary: Rhopalosiphum padi and Rhopalosiphum maidis are two common phloem-sucking pests on maize which can even transmit viruses (i.e., maize dwarf mosaic virus, MDMV) leading to severe yield losses of maize. Population genetic studies provide information about how much ecological and genetic divergence has occurred among many near and distant populations. We investigated the genetic diversity of both Rhopalosiphum aphids collected from maize in China and Europe, and we found that different populations of R. maidis showed low genetic variation, indicating a high level of gene flow of both nuclear and mitochondrial genes in this aphid. However, the mitochondrial gene of R. padi exhibited obvious genetic differentiation between Chinese samples and European samples. In conclusion, the domestic populations of both R. padi and R. maidis showed low genetic diversity, and the long distance between China and Europe may interrupt the gene exchange of aphids. Population genetic studies can reveal clues about the evolution of adaptive strategies of aphid species in agroecosystems and demonstrate the influence of environmental factors on the genetic diversity and gene flow among aphid populations. To investigate the genetic diversity of two Rhopalosiphum aphid species from different geographical regions, 32 populations (n = 535) of the bird cherry-oat aphid (Rhopalosiphum padi Linnaeus) and 38 populations (n = 808) of the corn leaf aphid (Rhopalosiphum maidis Fitch) from China and Europe were analyzed using one nuclear (elongation factor-1 alpha) and two mitochondrial (cytochrome oxidase I and II) genes. Based on the COI-COII sequencing, two obvious clades between Chinese and European populations and a low level of gene flow (Nm = 0.15) were detected in R. padi, while no geographical-associated genetic variation was found for EF-1α in this species. All genes in R. maidis had low genetic variation, indicating a high level of gene flow (Nm = 5.31 of COI-COII and Nm = 2.89 of EF-1α). Based on the mitochondrial result of R. padi, we concluded that the long distance between China and Europe may be interrupting the gene flow. The discordant results of nuclear gene analyses in R. padi may be due to the slower evolution of nuclear genes compared to mitochondrial genes. The gene exchange may occur gradually with the potential for continuous migration of the aphid. This study facilitates the design of control strategies for these pests. [ABSTRACT FROM AUTHOR]

Truffle is ectomycorrhizal ascomycota and produces hypogeous edible ascocarps, which was globally acknowledged as one of the most expensive food in the gastronomy market due to its unique flavor and texture, good culinary properties as well as health value. The volatile organic compounds (VOCs) are the important contributor for truffle unique flavor. In this study, the VOCs of the Chinese black truffle T. indicum ascocarps from seven different geographical regions and five harvest time in China were analyzed using gas chromatography–mass spectrometry (GC–MS). Total 589 compounds were analyzed and 1-octen-3-ol had the highest content in all analyzed samples. Discriminant analysis was carried out on the VOCs to build the models which can determine T. indicum collection region and time authenticity. This study clearly illustrated the characteristics of the VOCs profile of Chinese black truffle in relation to geographical regions and harvest time and provide profitable information for the scientific collection, conservation and utilization of the precious truffle resources in China in future. [ABSTRACT FROM AUTHOR]

Developing an individual tree diameter increment (ΔDBH) model is the basis of near-natural management of mixed, uneven-aged oak forests. This analysis used remeasurement data (2009–2014) comprising 6154 observations from 112 permanent plots in central China to develop and compare an indicator variable model (IVM) and a mixed-effect model (MEM) to estimate ΔDBH. First, a basic model was estimated using 12 potential explanatory variables. Geographical regions (GR), competition intensities (CI) and species compositions (SC) were introduced into the basal model as indicator variables or mixed effects, step by step, and then the prediction accuracy of IVM and MEM was compared. The results showed that (1) the independent variables significantly affecting ΔDBH included the reciprocal of DBH, basal area, altitude, and mean annual rainfall; (2) the introducing GR could not improve the accuracy of estimating ΔDBH, but the CI and SC could. (3) Compared with the basic model and IVM, the percentage mean absolute deviation of MEM decreased by 2.07% and 1.11%, while the root mean square error decreased by 0.06 and 0.04, respectively. The MEM including CI and SC as a random effect showed the best predictive performance and can be applied to improve the prediction of individual oak trees ΔDBH. [ABSTRACT FROM AUTHOR]

It is well known that the microbes associated with truffle fruiting bodies play a very important role during the truffle lifecycle. Tuber indicum , commonly called Chinese black truffle, is a species endemic to Eastern Asia and in the genus of Tuber. Here, we reported the bacterial communities of T. indicum from different geographical regions and described the bacterial diversity from three compartments (soil, ectomycorrhizae and ascocarps) of T. indicum using high-throughput sequencing combined tissue culture. The results revealed that Bradyrhizobium was the dominant genus in fruiting bodies of T. indicum from nine geographical sites in China, and the microbes in T. indicum ascocarps were influenced by geological locations and soil characteristics. More specific bacterial taxa were enriched in the fruiting bodies than in the ectomycorrhizae and soil. In addition, 60 cultural bacteria were isolated from T. indicum fruiting bodies (4 families, 24 genera), and Pseudomonas, Alcaligenes faecalis, Microbacterium , and Arthrobacter were dominant. One of 13 strains that have potential nitrogen-fixation activities was further verified by an acetylene reduction assay (ARA). Together, this research provides new and important data for better understanding of the interaction between truffle and associated microbe and the biology of truffle itself. [ABSTRACT FROM AUTHOR]

Antibiotic resistance genes (ARGs) represent emerging environmental pollutants that present health risks. Drinking water supply systems (DWSSs), including sources to tap water, play crucial roles in the dissemination and propagation of ARGs. However, there was a paucity of knowledge on the relative abundance, diversity, mobility, and pathogenic hosts of ARGs in DWSSs from source to tap. Therefore, the effects of treatments and distributions on the microbial community and ARGs from three geographical regions (downstream areas of the Yellow, Yangtze, and Pearl Rivers) were elucidated in the present study. Treatment processes lowered the complexity of the microbial community network, whereas transportation increased it. The assembly mechanisms of the microbial community and antibiotic resistome were primarily driven by stochastic processes. Distribution greatly increased the contribution of stochastic processes. Multidrug ARGs (for example, multidrug transporter and adeJ) and bacitracin ARG (bacA) were the primary mobile ARGs in drinking water, as identified by the metagenomic assembly. Achromobacter xylosoxidans, Acinetobacter calcoaceticus, and Acinetobacter junii harbored diverse multidrug ARGs and mobile genetic elements (MGEs) (recombinases, integrases, and transposases) as potential pathogens and were abundant in the disinfected water. Environmental factors, including pH, chlorine, latitude, longitude, and temperature, influenced the ARG abundance by directly regulating the MGEs and microbial community diversity. This study provides critical information on the fate, mobility, host pathogenicity, and driving factors of ARGs in drinking water, which is conducive to ARG risk assessment and management to provide high-quality drinking water to consumers., Competing Interests: Declaration of Competing Interest The authors declare that there are no known competing financial interests or personal relationships that could influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Controversies exist whether season of birth is associated with schizophrenia development later in life, and evidence has mainly come from studies done in developed countries. This study examines the association between season of birth and risk for schizophrenia in China, with special attention to geographical region, urbanity, and gender. Using data from China’s Second National Sampling Survey on Disability, a large-scale, nationally representative sample (N=2,052,694), this study employs discrete-time hazard models to compare the risk for schizophrenia development for people born in different seasons, and conducts subsample analyses by geographical region, urbanity, and gender. People born in the spring have the highest risk when compared to people born in the winter, summer or autumn. Furthermore, the relatively higher risk for people born in the spring is greater in the southern half of the country, in rural areas, and for women. The findings are consistent with results from a robustness check done among people who were conceived and born from 1955 to 1965, periods before, during, and after the 1959–1961 Chinese Famine. This study supports the presence of an association between season of birth and risk for schizophrenia development and of heterogeneity by geographical region, urbanity, and gender. [ABSTRACT FROM AUTHOR]

Rhubarb (Rhei Radix et Rhizoma) is a classic herbal laxative medicine in Europe and a very famous natural medicine in Asia, especially in China. In this study, near-infrared spectroscopy (NIRS) was first used for rapid and simultaneous analysis of five main active components (chrysophanol, aloe-emodin, rhein, emodin and physcion) in rhubarb of 6 geographical origins, processing and spurious samples. A total of 124 samples (73 raw, 40 processed and 11 spurious samples) were collected. With the reference values determined by HPLC, two calibration strategies, partial least squares (PLS) as a linear regression method and artificial neural networks (ANN) as a non-linear regression method, were studied. For the PLS strategy, 11 spectral pre-processing methods, 5 spectral regions and different latent variables (LVs) were systematically compared, while 3 spectral pre-processing methods and 5 ANN algorithms were studied for the ANN strategy. The results indicated that PLS was more suitable for the analysis of chrysophanol, aloe-emodin, emodin and physcion, whereas ANN was better for rhein. For the optimal NIR models of chrysophanol, aloe-emodin, rhein, emodin and physcion, the correlation coefficients of the calibration set (R cal ) were 0.9916, 0.9762, 0.9839, 0.9794 and 0.9800, respectively; the correlation coefficients of the prediction set (R pre ) were 0.9888, 0.9359, 0.9410, 0.9805 and 0.9785, respectively; the root mean square error of validation (RMSEP) were 0.0402, 0.0197, 0.0593, 0.0133 and 0.0192, respectively. Subsequently, the optimal NIR models were used to study the effects of geographical regions and processing, and identify the spurious rhubarb. Collectively, NIRS may be a well-acceptable method for quality evaluation of rhubarb and other traditional Chinese medicine (TCM)., (Copyright © 2018 Elsevier B.V. All rights reserved.)