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Interactions have greatly influenced recent scientific discoveries, but the identification of interactions is challenging in ultra-high dimensions. In this study, we propose an interaction identification method for classification with ultra-high dimensional discrete features. We utilize clique sets to capture interactions among features, where features in a common clique have interactions that can be used for classification. The number of features related to the interaction is the size of the clique. Hence, our method can consider interactions caused by more than two feature variables. We propose a Kullback-Leibler divergence-based approach to correctly identify the clique sets with a probability that tends to 1 as the sample size tends to infinity. A clique screening method is then proposed to filter out clique sets that are useless for classification, and the strong sure screening property can be guaranteed. Finally, a clique naïve Bayes classifier is proposed for classification. Numerical studies demonstrate that our proposed approach performs very well. [ABSTRACT FROM AUTHOR]

Term weighting is known as a text presentation strategy to assign appropriate value to each term to improve the performance of text classification in the task of transforming the content of textual document into a vector in the term space. Supervised weighting methods using the information on the membership of training documents in predefined classes are naturally expected to provide better results than the unsupervised ones. In this paper, a new weighting scheme is proposed via a matching score function based on a probabilistic model. We introduce a latent variable to indicate whether a term contains text classification information or not, specify conjugate priors and exploit the conjugacy by integrating out the latent indicator and the parameters. Then the non-discriminating terms can be assigned weights close to 0. Experimental results using kNN and SVM classifiers illustrate the effectiveness of the proposed approach on both small and large text data sets. [ABSTRACT FROM AUTHOR]

This study investigated the effects of selected four pharmaceutically active compounds (PhACs) (carbamazepine, sulfamethoxazole, ofloxacin, and roxithromycin) on the photosynthesis and antioxidant enzymes of Cyperus alternifolius in constructed wetlands (CWs). Moreover, the removal and kinetics of PhACs in CWs were evaluated to explore the related removal mechanisms. Results showed that C. alternifolius can uptake and withstand certain PhACs. The PhAC tolerance of C. alternifolius might be attributed to their capacity to maintain relatively normal photosynthetic activity and elevated antioxidative defense. CWs offered comparable or even higher removal efficiencies for the selected PhACs compared with conventional WWTPs. The removal of the target PhACs was enhanced in the planted CWs versus the unplanted CWs mostly because of plant uptake and rhizosphere effects. In particular, carbamazepine, which is considered the most recalcitrant of the PhACs, was significantly reduced ( p < 0.05). The removal of target PhACs fitted into two distinct periods. The initial fast step (within the first 2 h) was essentially attributed to the adsorption onto the CW medium surface. The subsequent slow process (2–12 h) closely followed first-order kinetics probably because of the interaction between microorganisms and plants. The obtained results indicate that C. alternifolius can phytoremediate PhAC-contaminated waters in CWs. [ABSTRACT FROM AUTHOR]

Feature subset selection is known to improve text classification performance of various classifiers. The model using the selected features is often regarded as if it had generated the data. By taking its uncertainty into account, the discrimination capabilities can be measured by a global selection index (GSI), which can be used in the prediction function. In this paper, we propose a latent selection augmented naive (LSAN) Bayes classifier. By introducing a latent feature selection indicator, the GSI can be factorized into each local selection index (LSI). Using conjugate priors, the LSI for feature evaluation can be explicitly calculated. Then the feature subset selection models can be pruned by thresholding the LSIs, and the LSAN classifier can be achieved by the product of a small percentage of single feature model averages. The numerical results on some real datasets show that the proposed method outperforms the contrast feature weighting methods, and is very competitive if compared with some other commonly used classifiers such as SVM. [ABSTRACT FROM AUTHOR]

Aims: Root system architecture (RSA) is important for nutrient and water acquisition efficiency. The adaptation of root growth and RSA to soil structure under conservative strip tillage (ST) system warrants further investigation. Methods: A three-year field experimentation was conducted in Northeast China to investigate the RSA and dynamic root growth of rain-fed maize under ST system by comparison with the conventional tillage (CT). Results: Grain yield in ST and CT was not significantly different, but their yield components differed. Compared to CT, grain number per ear was reduced by 4.4%, while 1000-grain weight was increased by 6.6% in ST. Root growth in ST plants was inhibited in the vegetative stage, as indicated by the reduced total root length (by 27.7–40.1%) compared to CT. During post-silking stage, the total root length was not different between ST and CT plants but the root xylem bleeding rate in ST plants was 70.7%-449.9% greater than that in CT. The uneven horizontal distribution of soil bulk density and soil temperature made the RSA of ST plants steeper compared to CT. Moreover, the D95 of root distribution in ST plant roots was greater. Conclusions: In ST system, colder, more compacted soil in the inter-row soil likely caused the lower root growth and consequently lower shoot dry matter during the vegetative stage. However, root senescence was delayed which was beneficial for water and nitrogen acquisition during grain filling. Strategies to improve early root growth may increase maize productivity in ST systems. [ABSTRACT FROM AUTHOR]

A two-year field experiment was conducted to elucidate the adaptive growth mechanism of maize under strip-till (ST) compared with conventional-till (CT). The biomass accumulation of ST plants was significantly lower than CT until V14 (14th leaf), but restored thereafter with one below-ear-node leaf reduced. At silking, the accumulation of nitrogen (N) was reduced by 8.3–10.7% compared to CT. During post-silking, vegetative-N remobilization was reduced by 20.4%, post-silking N uptake increased by 33.9% in ST compared to CT. Leaf senescence was delayed and more green leaf area at physiological maturity in ST. It is concluded that ST plants have the mechanism of 'Recovery Growth Adaptation' to get the similar yield as in CT plants: (1) facilitating growth rate at around V14 when the soil temperature was greatly improved to stabilize ear growth and grain number; (2) getting to silking the same time as in CT plants, so as to ensure the duration of grain filling; (3) increasing post-silking N uptake to fulfill the demand of grain development and reduce leaf N remobilization, so as to maintain leaf function and increase thousand-grain weight, which compensate for the loss of grain number per ear. [ABSTRACT FROM AUTHOR]

To understand the physiological mechanisms involved in xanthine metabolism during salt priming for improving low-temperature tolerance, salt priming (SP), xanthine dehydrogenase inhibitor (XOI), exogenous allantoin (EA), and back-supplemented EA (XOI + EA) treatments were given and the low-temperature tolerance of sugar beet was tested. Under low-temperature stress, salt priming promoted the growth of sugar beet leaves and increased the maximum quantum efficiency of PS II (Fv/Fm). However, during salt priming, either XOI or EA treatment alone increased the content of reactive oxygen species (ROS), such as superoxide anion and hydrogen peroxide, in the leaves under low-temperature stress. XOI treatment increased allantoinase activity with its gene (BvallB) expression under low-temperature stress. Compared to the XOI treatment, the EA treatment alone and the XOI + EA treatment increased the activities of antioxidant enzymes. At low temperatures, the sucrose content and the activity of key carbohydrate enzymes (AGPase, Cylnv, and FK) were significantly reduced by XOI compared to the changes under salt priming. XOI also stimulated the expression of protein phosphatase 2C and sucrose non-fermenting1-related protein kinase (BvSNRK2). The results of a correlation network analysis showed that BvallB was positively correlated with malondialdehyde, D-Fructose-6-phosphate, and D-Glucose-6-phosphate, and negatively correlated with BvPOX42 , BvSNRK2 , dehydroascorbate reductase, and catalase. These results suggested that salt-induced xanthine metabolism modulated ROS metabolism, photosynthetic carbon assimilation, and carbohydrate metabolism, thus enhancing low-temperature tolerance in sugar beet. Additionally, xanthine and allantoin were found to play key roles in plant stress resistance. • Salt priming improves low temperature tolerance by xanthine metabolism. • Xanthine metabolism induced ROS and ABA signaling under low temperature stress. • Salt-induced xanthine metabolism regulates carbohydrate and nitrogen metabolite levels. • The effect of xanthine on low temperature tolerance was not completely replaced by allantoin. [ABSTRACT FROM AUTHOR]

Data objects with both numeric and categorical attributes are prevalent in many real-world applications. However, most of the partitional clustering algorithms dealing with such data may trap into local optima. To further promote the performance, a novel clustering algorithm, called ABC-K-Prototypes (Artificial Bee Colony clustering based on K-Prototypes), is presented on the basis of the K-Prototypes algorithm, the search strategy of the artificial bee colony, and the chaos theory. In the presented approach, the one-step k-prototypes procedure is first given, and then this procedure is combined with the search strategy of the artificial bee colony to address the mixed numeric and categorical data. In the search process of scout bees, the chaotic map is utilized to generate chaotic sequences for substituting the random numbers. To accelerate the convergence of the ABC-K-Prototypes algorithm, the multi-source search is adopted in the search process of scout bees. Finally, the performance of the ABC-K-Prototypes algorithm is demonstrated by a series of experiments on mixed numeric and categorical data in comparison with that of the other popular algorithms. [ABSTRACT FROM AUTHOR]

Drought severely affects the growth and yield of soybean plants especially during the flowering period. To investigate the effect of 2-oxoglutarate (2OG) in combination with foliar nitrogen (N) at flowering stage on drought resistance and seed yield of soybean under drought stress. This experiment was conducted in 2021 and 2022 on drought-resistant variety (Hefeng 50) and drought-sensitive variety (Hefeng 43) soybean plants treated with foliar N (DS + N) and 2-oxoglutarate (DS + 2OG) at flowering stage under drought stress. The results showed that drought stress at flowering stage significantly increased leaf malonaldehyde (MDA) content and reduced soybean yield per plant. However, superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities were significantly increased by foliar N treatment, and 2-oxoglutarate synergistically with foliar N treatment (DS + N + 2OG) was more beneficial to plant photosynthesis. 2-oxoglutarate significantly enhanced plant N content, glutamine synthetase (GS) and glutamate synthase (GOGAT) activity. Furthermore, 2-oxoglutarate increased the accumulation of proline and soluble sugars under drought stress. Under drought stress, soybean seed yield was increased by DS + N + 2OG treatment by 16.48–17.10% and 14.96–18.84% in 2021 and 2022, respectively. Thus, the combination of foliar N and 2-oxoglutarate better mitigated the adverse effects of drought stress and could better compensate for the yield loss of soybean under drought stress. [ABSTRACT FROM AUTHOR]

Understanding the differential fertilizer N fates among soil textures is important to optimize crop nitrogen (N) management for reducing N losses while enhancing crop yields and N use efficiency. In this study, two-year field experiments were conducted on three contrasting soil textures (clay, sandy and loamy soils) with an identical climate in Northeast China, to quantify fertilizer N fates in the maize cropping system and evaluate their responses to N rates (168, 240, and 312 kg N ha−1) under different soil textures using 15N tracer technique, further to model fertilizer N fates with soil properties using multiple linear regression. In two seasons, both grain yields and plant N accumulation were the highest on loamy soil, followed by clay soil, while the lowest on sandy soil. Compared with loamy and clay soils, the plant N accumulation derived from fertilizer (Ndff%) was significantly higher (47 %) on sandy soil in the 1st season, meanwhile its poor soil structure increased environmental N losses (ENL) while decreasing crop N recovery (CNR) and soil N residual (SNR); together with higher in-season ENL, this further significantly lower Ndff% (6%) on sandy soil in the 2nd season. Relative to loamy soil, the SNR on clay soil was significantly higher in both seasons due to the denser and heavier soil texture, but its CNR was lower in the 1st season while both CNR and ENL were higher in the 2nd season. Throughout two growing seasons, the total CNR of loamy, clay and sandy soil was 44 %, 34 % and 28 %, the total ENL was 41 %, 46 % and 64 %, and the final SNR was 15 %, 20 % and 8 %, respectively. With increasing N rates, total CNR decreased while final SNR increased on all three soils, and ENL increased in the 1st season but decreased in the 2nd season. Moreover, the N responses of CNR and SNR were higher on sandy soil, indicating that its fertilizer N fates were more susceptible to N rates. Therefore, crop N management strategies are required to be adjusted according to differential fertilizer N fates among soil textures. By establishing the model between fertilizer N fates with soil properties and N rates, we provided a promising approach to understand and predict fertilizer N use and loss for precisely optimizing N managements on different soil textures. [Display omitted] • Crop 15N recovery was higher on loamy soil (43.8 %) relative to clay soil (34.4 %) and sandy soil (28.1 %). • Soil 15N residual was higher on clay soil (19.6 %) relative to loamy soil (14.9 %) and sandy soil (7.6 %). • Total 15N loss was higher on sandy soil (64.3 %) relative to clay soil (46.0 %) and loamy soil (41.2 %). • The higher Ndff in 1st year but the lower Ndff in 2nd year were obtained on sandy soil than other soils. • Modelling the relationships between fertilizer 15N fates and the soil structure and N rates. [ABSTRACT FROM AUTHOR]

Plant genotypes shape root‐associated microbiota that affect plant nutrient acquisition and productivity. It is unclear how maize hybrids modify root‐associated microbiota and their functions and relationship with nitrogen use efficiency (NUE) by regulating rhizosphere soil metabolites. Here, two N‐efficient (NE) (ZD958, DMY3) and two N‐inefficient (NIE) maize hybrids (YD9953, LY99) were used to investigate this issue under low N (60 kg N ha−1, LN) and high N (180 kg N ha−1, HN) field conditions. NE hybrids had higher yield than NIE hybrids under LN but not HN. NE and NIE hybrids recruited only distinct root‐associated bacterial microbiota in LN. The bacterial network stability was stronger in NE than NIE hybrids. Compared with NIE hybrids, NE hybrids recruited more bacterial taxa that have been described as plant growth‐promoting rhizobacteria (PGPR), and less related to denitrification and N competition; this resulted in low N2O emission and high rhizosphere NO3−‐N accumulation. NE and NIE hybrids had distinct rhizosphere soil metabolite patterns, and their specific metabolites were closely related to microbiota and specific genera under LN. Our findings reveal the relationships among plant NUE, rhizosphere soil metabolites, root‐associated microbiota, and soil nutrient cycling, and this information is informative for breeding NE crops. [ABSTRACT FROM AUTHOR]

ATCC 14511 T (=DSM 40499, =NBRC 13413) is a type strain of Streptomyces griseochromogenes . It is known as a producer of nucleoside antibiotic, blasticidin S. In this report we present the complete genome sequence of S. griseochromogenes ATCC 14511 T , which consists of 10,764,674 bp with a linear chromosome, 9822 protein-coding genes, 6 rRNA operons, 74 tRNA and 3 sRNA. The genomic analysis revealed that 52 putative gene clusters are involved in the biosynthesis of secondary metabolites, including four gene clusters of nucleoside antibiotics. These gene clusters provide a beneficial source for production of bioactive natural compounds. [ABSTRACT FROM AUTHOR]

Feature selection is a practical approach for improving the performance of text classification methods by optimizing the feature subsets input to classifiers. In traditional feature selection methods such as information gain and chi-square, the number of documents that contain a particular term (i.e. the document frequency) is often used. However, the frequency of a given term appearing in each document has not been fully investigated, even though it is a promising feature to produce accurate classifications. In this paper, we propose a new feature selection scheme based on a term event Multinomial naive Bayes probabilistic model. According to the model assumptions, the matching score function, which is based on the prediction probability ratio, can be factorized. Finally, we derive a feature selection measurement for each term after replacing inner parameters by their estimators. On a benchmark English text datasets (20 Newsgroups) and a Chinese text dataset (MPH-20), our numerical experiment results obtained from using two widely used text classifiers (naive Bayes and support vector machine) demonstrate that our method outperformed the representative feature selection methods. [ABSTRACT FROM AUTHOR]

• The antibiotics were not detected in grains and heavy metals did not exceed limits. • MRGs ruvB and acn , and ARGs sul1 and sul2 were the dominating resistant genes. • Co-selection may serve as a potential mechanism for resistance maintenance. • MRG CzcA and ARG sul1 can be recommended as model genes to study the co-selection. • Proteobacteria were the most influential hosts for MRG, ARG, and integrons. Secondary municipal-treated wastewater irrigation may introduce residual antibiotics into the agricultural systems contaminated with certain heavy metals, ultimately leading to the coexistence of antibiotics and heavy metals. The coexistence may induce synergistic resistance to both in the microbial community. Here, we investigated the effects of long-term municipal-treated irrigation for rice on the microbiome and resistome. The results showed that the target antibiotics were undetectable in edible grains, and the heavy metal concentrations did not exceed the standard in edible rice grains. Heavy metal resistance genes (MRGs) ruvB and acn antibiotic resistance genes (ARGs) sul1 and sul2 were the dominating resistant genes. The coexistence of antibiotics and heavy metals affected the microbial community and promoted metal and antibiotic resistance. Network analysis revealed that Proteobacteria were the most influential hosts for MRGs, ARGs, and integrons, and co-selection may serve as a potential mechanism for resistance maintenance. MRG czcA and ARG sul1 can be recommended as model genes to study the co-selection of ARGs and MRGs in environments. The obtained results highlight the importance of considering the co-occurrence of heavy metals and antibiotics while developing effective methods to prevent the transmission of ARGs. These findings are critical for assessing the possible human health concerns associated with secondary municipal-treated wastewater irrigation for agriculture and improving the understanding of the coexistence of heavy metals and antibiotics. [Display omitted] [ABSTRACT FROM AUTHOR]

Ordinary differential equations (ODEs) are important mathematical models in applied sciences to describe dynamic processes. The parameters involved in the models usually have specific meanings, and hence need to be estimated from the observed data. In applications, the parameters may change with time, which are called time-varying parameters. In this paper, we propose a Bayesian penalized B-spline method to estimate the time-varying parameters and initial values in ODEs. Simulation studies show that this method is more efficient than the two-stage local polynomial method. Furthermore, we introduce the DIC model selection criterion to determine the number of knots of B-splines. [ABSTRACT FROM AUTHOR]

The mixture of controlled-release urea (CRU) and normal urea (MCU) applied as one-time basal fertilizer is a convenient and effective alternative to traditional split-nitrogen (N) fertilization, can ensure a sufficient late-season N supply to increase maize yield. However, the effects of MCU ratios on maize root development, post-silking growth, and grain-filling process remain poorly understood. In this study, 3-year field experiments were conducted on sandy and clay soils in Northeast China, to evaluate maize yield responses to different MCU ratios (from 0% to 60% at 15% intervals). Four key treatments, i.e., N omission (N0), MCU0%, MCU30%, and MCU60%, were then selected to investigate root traits, post-silking plant growth and N uptake, grain-filling parameters, and their relationships with grain yields. Across different soils and years, grain yields showed a parabolic curve with increasing MCU ratios, with the highest yields obtained in MCU30%. On average, MCU30% increased grain yield by 22.3% and 11.7% on sandy and clay soils, respectively, relative to MCU0%. The appropriate early-N supply in MCU30% promoted root growth by allocating more dry matter (DM) to roots, while increasing total root length by producing more and longer crown roots, as well as higher lateral root length. The well-developed roots in MCU30% increased post-silking plant N uptake under sufficient late-N supply, thereby delayed leaf senescence and improved DM production for grain-filling, ultimately increased kernel weight and grain yield. Compared to MCU30%, MCU60% showed similar growth and yield performances on clay soil. In contrast, MCU60% performed notably worse on sandy soil due to limited CRU-N release at early period under inherently lower soil moisture and fertility levels. Our measurements and correlation analysis support the conclusion that MCU30% effectively sustain leaf longevity and increase post-silking DM by optimizing root growth and morphology under an optimal N supply pattern during maize growing season, thus improving grain-filling and final yield. The results advance our understanding of how MCU method affects maize post-silking growth and yield formation, providing important insights for optimizing crop N management by regulating root development, especially on lower fertility soils. • Higher yield in MCU30% was driven by increased post-silking DM and improved grain-filling rate. • Compared to MCU30%, maize plants in MCU60% performed equally on clay soil, but worse on sandy soil. • MCU30% increased root length by producing more, longer crown roots while elongating lateral roots. • The well-developed root enhanced post-silking N uptake and reduced vegetative-N mobilization. [ABSTRACT FROM AUTHOR]

To increase crop productivity while reducing environmental costs, an integrated soil–crop system management (ISSM) strategy was developed and successfully adopted in China. However, little information is available on the long-term ISSM effects on maize agronomic and environmental performance. Therefore, we evaluated the effects of ISSM with combining inorganic and organic fertilizers on maize productivity, N use efficiency (NUE) and N balance and losses as compared with farmers' practice (FP) and high-yielding practice (HY), based on an 11-year field experiment in Northeast China. Maize yield in ISSM (11.7–14.3 Mg ha−1) achieved 97.7% of that in HY and was increased by 27% relative to FP. The excellent yield performance in ISSM was mainly attributed to optimum plant population structure and yield components. Annual N surplus in ISSM was only 7 kg ha−1, which was considerably lower than that in FP (52 kg ha−1) and HY (109 kg ha−1). Consequently, ISSM obtained significantly lower N losses and greenhouse gases emissions and higher NUE. In contrast to FP, crop performance in ISSM showing better sustainability and inter-annual stability. In conclusion, ISSM is an effective strategy to achieve long-term sustainable high crop yields and NUE with less environmental costs in the intensive agricultural system. [ABSTRACT FROM AUTHOR]

Experiments were conducted to study the adsorption kinetics and isothermal adsorption mechanism of nitrification inhibitor nitrapyrin onto the black soil of northeastern China. The nitrapyrin adsorption kinetics of the black soil were fitted with a quasi-second-order kinetics equation before and after organic matter removal (R2 ≥ 0.8320, p <.05). The adsorption isotherm was obtained by the Langmuir equation (R2 ≥ 0.9400, p <.05). Isothermal adsorption requires less energy and is a spontaneous endothermic reaction with an L-type isothermal curve (n > 1), dominated by surface physical adsorption. With the decrease of organic matter content in black soil, the adsorption mechanism of nitrapyin changed from distribution mechanism to surface adsorption. The black soil's organic matter content exhibited a quadratic relation with the maximum adsorption capacity and adsorption constant (Kf) at the different temperatures, reaching significant levels (R2 ≥ 0.6484, p <.05). [ABSTRACT FROM AUTHOR]

• Incapability of gammabaculovirus NeleNPV DNA polymerase in functional substitution with that of alphabaculovirus AcMNPV. • NeleNPV DNA polymerase is not localized to nucleus. • NeleNPV DNA polymerase fused with a known NLS could partially rescue viral replication in dnapol -null AcMNPV bacmid. DNA polymerase (DNApol) is highly conserved in baculovirus and is required for viral DNA replication. However, little is known about gammabaculovirus DNApol. Here DNApol of the gammabaculovirus Neodiprion lecontei nucleopolyhedrovirus (NeleNPV) was cloned into a dnapol -null alphabaculovirus AcMNPV bacmid, creating Bac-GFP-AcΔPol-NlPol. The resulting recombinant bacmid did not spread to neighboring cells, virus growth curve and real-time PCR revealed that NeleNPV dnapol substitution did not rescue AcMNPV DNA replication and virus production. Immunofluorescence microscopy revealed that NeleNPV DNApol was expressed but could not localize to the nucleus. Subsequently NeleNPV DNApol was fused to SpltNPV DNApol nuclear localization signal (NLS) and the fused DNApol could import into nucleus. The NLS-fusing NeleNPV DNApol was further transposed into the dnapol -null AcMNPV bacmid, creating Bac-GFP-AcΔPol-HA:NlPolNLS. The recombinant virus could replicate and produce infectious virus in Sf9 cells, albeit at reduced levels compared to wild type AcMNPV. Taken together, our results suggested that the NLS deficiency of NeleNPV DNApol blocked viral DNA replication and production of infectious virus in dnapol -null AcMNPV bacmid. [ABSTRACT FROM AUTHOR]

Abstract Cyperus alternifolius based mesocosm-scale constructed wetland was employed to remove pharmaceuticals. We investigated the microbial community composition using phosphor lipid fatty acids (PFLAs) analysis and substrate enzyme activity during long-term exposure to pharmaceuticals in mesocosm-scale constructed wetlands. The results showed that there was no visible inhibition effect of pharmaceuticals on CW substrate enzymes activities in the experimental range (0–500 μg/L). Microbial communities, as revealed by PFLAs, were enhanced by the presence of plants, while the PFLAs content was highest when the pharmaceutical concentration was 10 μg/L or 30 μg/L at CWs. Except for anaerobic bacteria and Saturated fatty acids, the maximum PLFAs levels were reached when the pharmaceuticals were 10 μg/L or 30 μg/L, while Bacteria, G (−), fungal bacteria, Aerobic bacteria and Monounsaturated fatty acids were remarkably affected by high pharmaceuticals (100–500 μg/L). However, the main microbial florae were not changed among the treatments. In this study, the removal efficiencies of the studied pharmaceuticals in Planted (30) was greatest, which could be attributed to the higher microbial biomass. These results indicate that C. alternifolius can phytoremediate pharmaceutical-contaminated waters in CWs. Individual fatty acid cannot be used to represent specific species; therefore, more approaches to species identification such as rRNA-based methods must be included in future studies to better understand the metabolic mechanisms of microorganisms involved in the removal of studied pharmaceuticals and improve the performance of CWs. Highlights • The microbial community and enzyme activity were evaluated during long-term stress. • Enzyme activity was not inhibited in the experimental range (0–500 μg/L). • The main microbial florae were not affected in laboratory experiments. • The total PLFAs did not differ obviously in response to low pharmaceuticals in CWs. [ABSTRACT FROM AUTHOR]

Pseudomonas is a Gram-negative, rod-shaped bacteria. Many members of this genus displayed remarkable physiological and metabolic activity against different plant pathogens. However, Pseudomonas mosselii has not yet been characterized in biocontrol against plant disease. Here we isolated a strain of P. mosselii BS011 from the rhizosphere soil of rice plants, and the isolate showed strong inhibitory activity against the rice blast fungus Magnaporthe oryzae. Further we sequenced the complete genome of BS011, which consist of 5.75 Mb with a circular chromosome, 5,170 protein-coding genes, 23 rRNA and 78 tRNA operons. Bioinformatic analysis revealed that seven gene clusters may be involved in the biosynthesis of metabolites. Gene deletion experiments demonstrated that the gene cluster c-xtl is required for inhibitory activity against M. oryzae. Bioassay showed that the crude extract from BS011 fermentation sample significantly inhibited the development of M. oryzae at a concentration of 10 μg/ml. Besides, we illustrated that the crude extract of BS011 impaired the appressorial formation in a dose dependent manner. Collectively our results revealed that P. mosselii BS011 is a promising biocontrol agent and the gene cluster c-xtl is essential for inhibiting the development of M. oryzae. [ABSTRACT FROM AUTHOR]

DNA polymerase (DNApol) is present in all baculoviruses and plays a crucial role in viral DNA replication. Previously we showed that the DNApol of the alphabaculovirus group II Spodoptera litura nucleopolyhedrovirus (SpltNPV) could partially substitute for the DNApol of a group I alphabaculovirus, Autographa californica multiple nucleopolyhedrovirus (AcMNPV). However, it is not known if a betabaculovirus DNApol could subsititute for the alphabaculovirus DNApol in AcMNPV. In this report, DNApol of the betabaculovirus Pieris rapae granulovirus (PiraGV) was inserted into a dnapol-null AcMNPV bacmid, creating Bac-AcΔpol:PrPol. The repair virus did not spread to neighboring cells; virus growth curve and real-time PCR revealed that the PiraGV dnapol substitution abrogated AcMNPV DNA replication and virus production. Immunofluorescence microscopy showed that PiraGV DNApol could be expressed and localized to the nucleus. Collectively, our results suggested that the alphabaculovirus AcMNPV DNApol could not be replaced by a DNApol from the betabaculovirus, PiraGV. [ABSTRACT FROM AUTHOR]

The presence of pharmaceutically active compounds (PhACs) in wastewater treatment plant effluent poses a potential risk to aquatic ecosystems. Constructed wetlands have recently been used to control PhACs. However, the microbial communities that are involved in these processes have not been comprehensively investigated. This study aimed to evaluate the removal of PhACs and microbial response in constructed wetlands during the treatment of PhACs. The effects of PhACs on bacterial communities in constructed wetland mesocosms were analyzed by Illumina MiSeq sequencing technology. Results indicated that removal efficiencies of PhACs were enhanced over time, and constructed wetlands offer higher removal efficiencies for the PhACs studied compared to conventional wastewater treatment plants. Plants improved microbial richness and diversity while both indices were negatively correlated with PhAC concentrations ranging from 30 to 500 μg/L in constructed wetland mesocosms. The microbial communities of the constructed wetland mesocosms were dominated by Proteobacteria, Acidobacteria, and Bacteroidetes under PhAC exposure, while Desulfobulbus and Treponema were the dominant genera. In particular, Proteobacteria were correlated with PhAC concentrations. Overall, this study provides valuable microbial community ecology data to understand how microbial populations respond to PhAC stress in constructed wetlands. [ABSTRACT FROM AUTHOR]

• Rectangular MZs providing a basis for site-specific management in the maize field. • Correlations of soil-crop attributes and yield varied across MZs and growth stages. • Main factors' contributions to yield had various characteristics among MZs. Spatial variability of soil properties, crop performance, fertilization management, and tillage methods play an important role in yield prediction and improvement. However, the farm nutrient management in most regions of the world is still based on conventional and uniform management strategies, without take into consideration the spatial variability of the above factors. Therefore, the objectives of this study were to delineate potential management zones (MZs), with the considering of spatial variability of soil properties, crop performance, fertilization management, tillage methods, and investigate their relationships with yield, and their contributions to yield in each management zone. A 1.60 ha maize field with fertilizer and tillage management, in Lishu County, Jilin Province, China, was selected as the study area and soil samples with soil organic matter, total nitrogen and soil pH measured values, crop samples with crop height, leaf nitrogen content, above ground biomass at V6, silking, and maturity growth stages, and yield measured values were collected in 2019 and 2020. Firstly, the rectangular MZs were defined to divide the study area into relatively homogeneous areas based on the spatial variability of soil properties, crop performance, and yield of 2019 and 2020. Secondly, the correlations of soil properties and crop performance with yield were obtained across MZs and growth stages in 2019 and 2020. Lastly, the yield prediction models were established based on the above four types of factors by using random forest (RF) model and the contributions of main factors were obtained quantitatively across different MZs and years. The results showed that (1) the small maize field was divided into three rectangular MZs and most of the soil and crop attributes presented homogeneous characteristics in each zone; (2) correlations of soil properties and crop performance with yield varied across different MZs and growth stages, and even different years; (3) RF model obtained good performance across MZs and years, with R2 = 0.86 and RMSE = 0.77 kg/ha in 2019 and R2 = 0.89 and RMSE = 1.04 kg/ha in 2020 both for the whole field. The contribution of main factors for yield varied across both MZs and years, while some characteristics of the main factors' contributions remain unchanged. This study would open the opportunity to farmers and agricultural experts for site-specific nutrient management in the maize field. [ABSTRACT FROM AUTHOR]

Viral pathogens are a major threat to stable crop production. Using a backcross strategy, we find that integrating a dominant brown planthopper (BPH) resistance gene Bph3 into a high-yield and BPH-susceptible indica rice variety significantly enhances BPH resistance. However, when Bph3-carrying backcross lines are infested with BPH, these BPH-resistant lines exhibit sterile characteristics, displaying panicle enclosure and failure of seed production at their mature stage. As we suspected, BPH-mediated viral infections could cause the observed sterile symptoms, and we characterized rice-infecting viruses using deep metatranscriptomic sequencing. Our analyses revealed eight novel virus species and five known viruses, including a highly divergent virus clustered within a currently unclassified family. Additionally, we characterized rice plant antiviral responses using small RNA sequencing. The results revealed abundant virus-derived small interfering RNAs in sterile rice plants, providing evidence for Dicer-like and Argonaute-mediated immune responses in rice plants. Together, our results provide insights into the diversity of viruses in rice plants, and our findings suggest that multiple virus infections occur in rice plants. [ABSTRACT FROM AUTHOR]

• Crop height explained the most variability in maize AGB estimation of V6 stage. • EVI and VARI were selected as the most important narrowband VIs at the R1 stage. • mSR 705 , Vi opt , SRPI, REIP-LI, NDI, Maccioni were important VIs at the R3 stage. • XGBoost model outperformed stepwise and RF regression model in maize AGB estimation. • UAV-based hyperspectral imagery has some advantages for AGB estimation. Monitoring the aboveground biomass (AGB) of maize is essential for improving site-specific nutrient management and predicting yield to ensure food safety. A low-altitude unmanned aerial vehicle (UAV) was employed to acquire hyperspectral imagery of the maize canopy at three growth stages (V6, R1, R3) to estimate the maize AGB. Five maize nitrogen (N) rate experiments were conducted in Lishu County, Jilin Province, Northeastern China, to create different biomass conditions. Combined with crop height data obtained from the field measurements, 30 narrowband vegetation indices (VIs) were extracted using surface reflectance data from the hyperspectral imagery. Stepwise regression, random forest (RF) regression and XGBoost regression models were used to predict the fresh and dry AGB of the 2019 growth season. The study revealed that (1) crop height explained the most variability (60–70%) in the maize dry and fresh AGB estimation of the V6 growth stage, while different VIs exhibited various importance for AGB estimation at other maize growth stages; (2) XGBoost regression models demonstrated high prediction accuracy in both fresh and dry AGB estimation, compared with stepwise regression and RF models. (3) XGBoost models also presented high prediction accuracy at each single-growth stage and the whole-growth stage, with the highest accuracy for the dry AGB at V6 growth stage (R2 = 0.81, RMSE = 0.27 t/ha). This study demonstrated the capability of UAV-based hyperspectral imagery for estimating maize AGB at the field scale, which can be used to assist precision agriculture. [ABSTRACT FROM AUTHOR]

Abstract: orf18 (ac18) of Autographa californica multiple nucleopolyhedrovirus (AcMNPV) is a highly conserved gene in lepidopteran nucleopolyhedroviruses, but its function remains unknown. In this study, an ac18 knockout AcMNPV bacmid was generated to determine the role of ac18 in baculovirus life cycle. After transfection of Sf-9 cells, the ac18-null mutant showed similar infection pattern to the parent virus and the ac18 repair virus with respect to the production of infectious budded virus, occlusion bodies, or the formation of nucleocapsids as visualized by electron microscopy. The deletion mutant did not reduce AcMNPV infectivity for Trichoplusia ni in LD50 bioassay; however, it did take 24 h longer for deleted mutant to kill T. ni larvae than wild-type virus in LT50 bioassay. Our results demonstrate that ac18 is not essential for viral propagation both in vitro and in vivo, but it may play a role in efficient virus infection in T. ni larvae. [Copyright &y& Elsevier]

Using secondary treated wastewater to irrigate paddies presents an exposure pathway for antibiotics to enter the terrestrial food chain. To date, there has been no information on the biochemical reactions and antibiotic uptake in rice plants irrigated with secondary treated wastewater. The present study investigated antibiotic uptake and concentration-response trends in rice tissues and evaluated the effects of typical antibiotics (tetracycline, roxithromycin, ofloxacin, and sulfamethoxazole) on rice growth, grain yield and quality, and rice physiobiochemical characters via irrigation using treated wastewater augmented with varying concentrations (0–500 µg/L) in paddies. The results showed that the antibiotic accumulation in rice plants irrigated with treated wastewater was limited, and the studied antibiotics were not detected in rice grains (edible parts). The ability of rice to withstand certain antibiotics and grow in a healthy manner is attributed to the capacity to maintain reasonably normal photosynthesis activity and to elevate antioxidative defenses. The highest antibiotic concentration (500 µg/L) did not reduce the processing quality of the rice grain, but it enhanced the cooking and eating quality. From the obtained results, it can be concluded that secondary treated wastewater for paddy irrigation is an alternative water resource securing protection from the environment and rice grain quality. [Display omitted] • The antibiotic levels were not detected in rice grains. • The generation of ROS was not beyond the antioxidative capability of rice to neutralize them. • The antibiotics reduced the processing quality but improved the cooking and eating quality of rice. • Secondary treated wastewater could be safely applied for irrigation. [ABSTRACT FROM AUTHOR]

Low temperatures seriously depress germination and seedling establishment in wheat and it is of great significance to explore approaches to improve wheat tolerance to low temperatures. In this study, the effects of seed pre-soaking and parental treatment with melatonin on seed germination and low temperature tolerance during the early growing stage in wheat were studied. The results showed that pre-soaking with melatonin increased the germination rate, improved antioxidant capacity and accelerated starch degradation under low temperature, which alleviated low temperature-induced damage to the chloroplasts in coleoptiles of wheat seedlings. Parental melatonin treatment during grain filling stage significantly decreased the grain weight. Seeds from parental melatonin-treated plants showed higher germination rates and higher antioxidant enzyme activity than the control seeds under low temperature. In addition, parental treatment with melatonin modulated the activities of carbohydrate metabolism enzymes, which contributes to enhanced low temperature tolerance in wheat offspring. It was suggested that both seed pre-soaking and parental treatment with melatonin could be the effective approaches for low temperature tolerance induction in wheat. [ABSTRACT FROM AUTHOR]

Pseudomonas azotoformans is a Gram-negative bacterium and infects cereal grains, especially rice. P. azotoformans S4 from soil sample derived from Lijiang, Yunnan Province, China, appeared to be strong inhibitory activity against Fusarium fujikurio , a serious rice fungal pathogen. Here, we present the complete genome of P. azotoformans S4, which consists of 6,859,618 bp with a circle chromosome, 5991 coding DNA sequences, 70 tRNA and 19 rRNA. The genomic analysis revealed that 9 candidate gene clusters are involved in the biosynthesis of secondary metabolites. [ABSTRACT FROM AUTHOR]