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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]

Invertebrate species are a natural reservoir of viral genetic diversity, and invertebrate pests are widely distributed in crop fields. However, information on viruses infecting invertebrate pests of crops is limited. In this report, we describe the deep metatranscriptomic sequencing of 88 invertebrate samples covering all major invertebrate pests in rice fields. We identified 296 new RNA viruses and 13 known RNA viruses. These viruses clustered within 31 families, with many highly divergent viruses constituting potentially new families and genera. Of the identified viruses, 13 RNA viruses clustered within the Fiersviridae family of bacteriophages, and 48 RNA viruses clustered within families and genera of mycoviruses. We detected known rice viruses in novel invertebrate hosts at high abundances. Furthermore, some novel RNA viruses have genome structures closely matching to known plant viruses and clustered within genera of several plant virus species. Forty-five potential insect pathogenic RNA viruses were detected in invertebrate species. Our analysis revealed that host taxonomy plays a major role and geographical location plays an important role in structuring viral diversity. Cross-species transmission of RNA viruses was detected between invertebrate hosts. Newly identified viral genomes showed extensive variation for invertebrate viral families or genera. Together, the large-scale metatranscriptomic analysis greatly expands our understanding of RNA viruses in rice invertebrate species, the results provide valuable information for developing efficient strategies to manage insect pests and virus-mediated crop diseases. [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]

This article reports the first detection of papaya cytorhabdovirus (PCRV) in soybean plants in Zhejiang province, China. The soybean plants exhibited symptoms such as shrinkage, yellow spots, and chlorotic spots with yellowing. Through RNA extraction and sequencing, a contig with high nucleotide identity to PCRV was identified. RT-PCR assays confirmed the presence of PCRV in 9 out of 12 symptomatic soybean samples. This finding is significant as PCRV has previously been found in other hosts and monitoring for the virus and its vector host will be important for controlling its spread in China. The research was supported by the National Natural Science Foundation of China. [Extracted from the article]

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]

Keywords: Chickpea chlorotic stunt virus (CpCSV); Weed; Viruses EN Chickpea chlorotic stunt virus (CpCSV) Weed Viruses 1155 1156 2 09/15/23 20230801 NES 230801 Chickpea chlorotic stunt virus (CpCSV), a member of the genus I Polerovirus i of the family I Solemoviridae i , has been described in Ambo, Ethiopia (AY956384) and Yunnan, China (JF507725). The contig was 5,883 bp in size with an average sequencing coverage of 1721x, and showed 87.35% and 87.48% nucleotide identities with CpCSV isolates from Ethiopia and China, respectively. [Extracted from the article]

Agricultural production in China is facing great challenges to ensure food security and cleaner environment; further improvements are therefore required in crop nutrient management to increase grain yield and nutrient use efficiency while synchronously reducing environmental pollution. In this study, a total of 87 site-years of on-farm experiments were conducted from 2013 to 2018 in the main agro-ecological areas in Northeast China, to evaluate the agronomic and environmental benefits of nutrient expert (NE) system in maize and rice production. Results showed that NE had general and significant advantages in agronomic and environmental benefits relative to FP, by dramatically reducing N and P fertilizer inputs and optimizing nutrient management. As compared to FP, on average, NE increased grain yield by 8.4% and 6.6% significantly higher grain yield and N uptake for maize, respectively, while it obtained equal yield performance and 3.0% higher N uptake for rice, and consequently resulted in significantly higher N use efficiency. Environmental effects assessment showed that NE reduced substantially reactive N losses and greenhouse gas emissions by 46.9% and 37.2% for maize, respectively, and 10.1% and 6.6% for rice, respectively. Regression analysis indicated that NE effectively improved N use efficiency and mitigated environmental pollution was mainly associated with increasing plant N uptake and reduced N surplus. As compared to fertilization recommendation based on soil testing, NE system showed higher N use efficiency and better environmental benefits for both maize and rice. In conclusion, our results demonstrated that NE system is a feasible and promising approach to optimize crop nutrient management and promote cleaner agricultural production in Northeast China. [ABSTRACT FROM AUTHOR]

Variable ordering heuristics play a central role in solving constraint satisfaction problems. Combining two variable ordering heuristics may generate a more efficient heuristic, such as dom/deg. In this paper, we propose a novel method for combining two variable ordering heuristics, namely Pearson-Correlation-Coefficient-based Combination (PCCC). While the existing combination strategies always combine participant heuristics, PCCC checks whether the participant heuristics are suitable for combination before combining them in the context of search. If they should be combined, it combines the heuristic scores to select a variable to branch on, otherwise, it randomly selects one of the participant heuristics to make the decision. The experiments on various benchmark problems show that PCCC can be used to combine different pairs of heuristics, and it is more robust than the participant heuristics and some classical combining strategies. [ABSTRACT FROM AUTHOR]

Collaborative filtering is one of the most successful and extensive methods used by recommender systems for predicting the preferences of users. However, traditional collaborative filtering only uses rating information to model the user, the data sparsity problem and the cold start problem will severely reduce the recommendation performance. To overcome these problems, we propose two neural network models to improve recommendations. The first one called TDAE uses a denoising autoencoder to integrate the ratings and the explicit trust relationships between users in the social networks in order to model the preferences of users more accurately. However, the explicit trust information is very sparse, which limits the performance of this model. Therefore, we propose a second method called TDAE++ for extracting the implicit trust relationships between users with similarity measures, where we employ both the explicit and implicit trust information together to improve the quality of recommendations. Finally, we inject the trust information into both the input and the hidden layer in order to fuse these two types of different information to learn more reliable semantic representations of users. Comprehensive experiments based on three popular data sets verify that our proposed models perform better than other state-of-the-art approaches in common recommendation tasks. [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]