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Background and aims: Crop rotation can effectively alleviate the obstacles of continuous cropping and restore the agroecological balance, and then determining the optimal length of crop rotation is the cornerstone of effective crop rotation. To delve into this issue, we conducted a six-year rotation experiment aimed at exploring how different rotation lengths impact sugar beet yield, soil properties, and microbial communities. Methods: Conduct field experiments to gather rhizosphere soil samples from treatments with different rotation lengths of sugar beet and analyze their physicochemical properties and microbial characteristics. Subsequently, establish a model linking sugar yield with the physicochemical properties and microbial characteristics of the rhizosphere soil. Results: Sugar beet, sugar content, and sugar yield significantly increased while decreasing disease symptoms, with increases in crop rotation length. Longer rotations significantly ameliorated soil acidification and improved soil fertility. On the other hand, extending the crop rotation length significantly altered the community structure of microbial sub-communities with varying abundances. Additionally, the fungal diversity increased and ecological network became more complex, and a multitude of potentially beneficial microbiota were enriched in the rhizosphere soil with rotation length. Conclusion: These results demonstrate that extending the crop rotation length improved soil conditions, and increased sugar beet yield. In addition, we recommend that sugar beet rotation length should be at least three years or more. [ABSTRACT FROM AUTHOR]

Corn steep liquor-assisted microbial remediation has been proposed as a promising strategy to remediate cadmium (Cd)-contaminated soil. In this study, we determined Bacillus subtilis (K2) with a high cadmium (Cd) accumulation ability and Cd resistance. However, studies on this strategy used in the Cd uptake of Chinese cabbage are lacking, and the effect of the combined incorporation of corn steep liquor and K2 on the functions and microbial interactions of soil microbiomes is unclear. Here, we study the Cd uptake and transportation in Chinese cabbage by the combination of K2 and corn steep liquor (K2 + C7) in a Cd-contaminated soil and corresponding microbial regulation mechanisms. Results showed that compared to inoculant K2 treatment alone, a reduction of Cd concentration in the shoots by 14.4% and the dry weight biomass of the shoots and the roots in Chinese cabbage increased by 21.6% and 30.8%, respectively, under K2 + C7 treatment. Meanwhile, hydrogen peroxide (H2O2) and malondialdehyde (MDA) levels were decreased by enhancing POD and SOD activity, thereby reversing Cd-induced oxidative damage. Importantly, inoculation of K2 would decrease the diversity of the microbial community while enhancing the abundance of dominant species. These findings provide a promising strategy for reducing the Cd accumulation in Chinese cabbage and recovering soil ecological functions. [ABSTRACT FROM AUTHOR]

Drought stress significantly impacts global rice production, highlighting the critical need to understand the genetic basis of drought resistance in rice. Here, through a genome-wide association study, we reveal that natural variations in DROUGHT RESISTANCE GENE 9 (DRG9), encoding a double-stranded RNA (dsRNA) binding protein, contribute to drought resistance. Under drought stress, DRG9 condenses into stress granules (SGs) through liquid-liquid phase separation via a crucial α-helix. DRG9 recruits the mRNAs of OsNCED4, a key gene for the biosynthesis of abscisic acid, into SGs and protects them from degradation. In drought-resistant DRG9 allele, natural variations in the coding region, causing an amino acid substitution (G267F) within the zinc finger domain, increase DRG9’s binding ability to OsNCED4 mRNA and enhance drought resistance. Introgression of the drought-resistant DRG9 allele into the elite rice Huanghuazhan significantly improves its drought resistance. Thus, our study underscores the role of a dsRNA-binding protein in drought resistance and its promising value in breeding drought-resistant rice.Drought is one of the major abiotic stresses affecting rice growth and development. Here, the authors identify a dsRNA-binding protein positively regulates rice drought resistance through promoting stability of OsNCED4 mRNAs, transcript of a key gene for the biosynthesis of abscisic acid, via protein phase separation. [ABSTRACT FROM AUTHOR]

Key message: Here, we report that ZmAGO18b encoding an argonaute protein is a negative regulator of maize resistance against southern leaf blight. Southern leaf blight caused by fungal pathogen Cochliobolus heterostrophus is a destructive disease on maize throughout the world. Argonaute (AGO) proteins, key regulators in small RNA pathway, play important roles in plant defense. But whether they have function in maize resistance against C. heterostrophus is unknown. Association analysis between the nucleic variation of 18 ZmAGO loci with disease phenotype against C. heterostrophus was performed, and the ZmAGO18b locus was identified to be associated with resistance against C. heterostrophus. Overexpression of ZmAGO18b gene suppresses maize resistance against C. heterostrophus, and mutation of ZmAGO18b enhances maize resistance against C. heterostrophus. Further, we identified the resistant haplotype of ZmAGO18b by association analysis of natural variation in ZmAGO18b genomic DNA sequences with seedling resistance phenotypes against C. heterostrophus and confirmed the resistant haplotype is co-segregated with resistance phenotypes against C. heterostrophus in two F2 populations. In sum, this study reports that ZmAGO18b negatively regulates maize resistance against C. heterostrophus. [ABSTRACT FROM AUTHOR]

An increasing number of landslides are occurring during the construction of highways in mountainous areas all over the world. A recent highway landslide located in the mountainous region of Southwest China is taken as a representative example to carry out the initiation mechanism and deformation characteristics analysis, and study the intelligent partitioning method in this paper. The geological conditions of the landslide are obtained through detailed geological surveys and investigation. A three-dimensional (3D) monitoring network with a total of 72 multi-points, including 53 surface displacement monitoring points and 19 deep displacement monitoring holes, is established to examine the spatial deformation characteristics of the landslide for nearly 25 months. The monitoring results of the surface displacement show that the dynamic deformation of the landslide can be divided into three stages, namely initial deformation stage, accelerated deformation stage, and stabilization stage. Based on the strata distribution obtained by the borehole investigation and the results of deep displacement monitoring, the depth of the slip surface can be reliably determined. The smart contract method in blockchain technology combined with the multi-point monitoring dataset is novelty applied to realize the intelligent automatic partition of the highway landslide without any human involvement. This method can provide the basis for further independent analysis of different landslide zones. According to the investigation and analysis, the initiation mechanism for the highway landslides is attributed to both internal poor geological conditions and external intense precipitation and engineering excavation. [ABSTRACT FROM AUTHOR]

Major depression disorder, also known as depression, with a significant and persistent low mood as the main clinical features, is the main type of mood disorders. L-menthol (LM), the main active ingredient of mint, has been considered as safe and healthy natural ingredient by the Food and Drug Administration in the USA. In this study, LM (40 mg/kg, i.g.) produced antidepressant-like effect in the forced swimming test (FST) in mice. The sub-effective dose (5 mg/kg, i.g.) of LM combined with the sub-effective dose of fluoxetine (5 mg/kg, i.p.) or reboxetine (2.5 mg/kg, i.p.) could significantly shorten the immobility time in the FST. Pretreatment with ondansetron (a highly selective 5-HT3 receptor antagonist, 8 mg/kg, i.p.), bicuculline [a competitive γ-aminobutyric acid (GABA) antagonist, 4 mg/kg, i.p.] and haloperidol (a non-selective D2 receptor antagonist, 0.2 mg/kg, i.p.) significantly reversed the antidepressant-like effect of LM (40 mg/kg, i.g.). In contrast, prazosin (a α1-adrenoceptor antagonist, 1 mg/kg, i.p.) and N-methyl-D-aspartic acid (an agonist at the glutamate site, 75 mg/kg, i.p.) did not eliminate the antidepressant-like effect of LM. All of these above indicated that LM is able to induce an antidepressant-like effect mediated by the modification of 5-HTergic, GABAergic and DAergic systems in the FST. LM might be used as combination therapy in depressed patients and is a potential antidepressant. [ABSTRACT FROM AUTHOR]

The authors describe a fluorometric assay for microRNA. It is based on two-step amplification involving (a) strand displacement replication and (b) rolling circle amplification. The strand displacement amplification system is making use of template DNA (containing a sequence that is complementary to microRNA-21) and nicking enzyme sites. After hybridization, the microRNA strand becomes extended by DNA polymerase chain reaction and then cleaved by the nicking enzyme. The DNA thus produced acts as a primer in rolling circle amplification. Then, the DNA probe SYBR Green II is added to bind to ssDNA to generate a fluorescent signal which increases with increasing concentration of microRNA. The method has a wide detection range that covers the10 f. to 0.1 nM microRNA concentration range and has a detection limit as low as 1.0 fM. The method was successfully applied to the determination of microRNA-21 in the serum of healthy and breast cancer patients. [ABSTRACT FROM AUTHOR]

A selective and sensitive photoelectrochemical assay was proposed for microRNA detection based on the isothermal cycle hybridization amplification of microRNA-21 that originated from the specific cleavage activity of duplex-specific nuclease (DSN) toward a DNA probe in DNA-RNA double helix and in situ enzymatic production of electron donor of ascorbic acid. After the biotin-functionalized DNA probe hybridized with complementary target microRNA-21, the hybridized DNA probe could be cleaved by DSN and microRNA-21 was released back to the incubation solution. The released microRNA could be further hybridized with the remaining single-strand DNA probe; thus, the isothermal cycle hybridization amplification would be formed. As a result, little avidin-alkaline phosphatase conjugate could be captured due to the release of biotin originating from the DSN cleavage. The distinct photocurrent change between a control biosensor and the DSN cleavage biosensor achieved label-free microRNA-21 detection with the linear range from 1 to 500 fM. The fabricated biosensor showed high detection selectivity even for one-base mismatched sequence. The attempt was carried out to directly assay the expression level change of microRNA-21 in total RNA extracted from chicken fibroblast cells infected with subgroup J avian leukosis virus. [ABSTRACT FROM AUTHOR]