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Background and Aims: Phosphorus (P) deficiency is present in 70% of the world's arable land, and severely affects crop growth and productivity. In this study, the ameliorative effects of P-solubilizing Bacillus altitudinis WR10 on P deficiency in wheat were investigated and the underlying mechanisms were explored. Methods: Wheat was grown in half-strength Hoagland solution with KH2PO4 or Ca3(PO4)2 with or without WR10 inoculation for 14 days. Wheat biomass, root system architecture (RSA), and tissue P content were determined to evaluate the potential for alleviating P deficiency. To elucidate the underlying mechanisms, the ability of WR10 to produce organic acids (OAs), and its effects on root exudates and the ascorbic acid-glutathione (ASA-GSH) cycle in wheat were investigated. Results: WR10 significantly increased plant biomass and tissue P content, decreased the root/shoot ratio, and remodeled the RSA, predominantly by augmenting root diameter in P-deficient wheat. Under P deficiency, WR10 produced up to 72 OAs, including palmitic, fumaric, methylmalonic, elaidic, benzoic, and nonanoic acids, decreased pH of the culture solution, and increased soluble P content. Our split-root experiment and non-targeted metabolomics revealed that WR10 inoculation reprogrammed root exudated in P-deficient plants, which enhanced the contents of (−)-threo-isodihomocitric, (R)-2-ethylmalic, 4Z,7Z,10Z,13Z-hexadecatetraenoic, and colnelenic acids. In addition, WR10 significantly upregulated APX, MDHAR, DHAR, GR, and GS gene expression levels and increased the ASA and GSH contents involved in the ASA-GSH cycle, thereby decreasing H2O2 levels. Conclusion: B. altitudinis WR10 alleviates P deficiency in wheat by remodeling the RSA, improving P availability, and activating the ASA-GSH cycle. [ABSTRACT FROM AUTHOR]

Purpose: Iron (Fe) deficiency seriously affects crop growth and yield. This study investigated whether and how an endophytic isolate, strain Bacillus sp. WR12, alleviates Fe deficiency in wheat (Triticum aestivum L.). Methods: Bacillus sp. WR12 and wheat seedlings were hydroponically co-cultured for 2 weeks under Fe-deficient conditions. To evaluate the Fe deficiency alleviating potential, wheat growth parameters were compared. To elucidate possible mechanisms, the genome of WR12 was sequenced, and production of siderophores was detected. In addition, transcriptomes of wheat root were compared, and accumulation of phenolic compounds was measured. Results: Bacillus sp. WR12 significantly increased root length and dry weight, leaf chlorophyll content and Fe content in Fe-deficient wheat seedlings. Genome analysis of WR12 and CAS agar diffusion test demonstrated that WR12 had a dhbACEBF operon and produced siderophores. Significant upregulation of this operon and more siderophore synthesis in WR12 were observed when Fe was insufficient. Transcriptomic data of roots indicated change of expression of a large number of genes in Fe-deficient wheat after WR12 inoculation. Particularly, PAL, CYP73A, COMT, F5H, HCT and CAD genes involved in phenylpropane biosynthesis were significantly up-regulated. Moreover, elevated phenol accumulation was detected in the root of wheat after inoculation with WR12 under Fe deficiency. Conclusions: Bacillus sp. WR12 alleviates Fe deficiency in wheat and this can be partially attributed to enhanced siderophore production and phenol accumulation. [ABSTRACT FROM AUTHOR]

An immunochromatographic lateral flow strip test (ILFST) for the rapid detection of danofloxacin (DAN) in milk samples was developed based on colloidal gold-labeled anti-DAN monoclonal antibody 3E9 and a competitive format. Quantitative detections of DAN-spiked samples using the ILFST gave a half inhibitory concentration (IC50) of 0.513 ng/mL and a limit of detection (LOD) of 0.092 ng/mL. Recoveries of DAN from spiked milk samples were from 80.0 to 95.1% within an assay (intra-assay) and from 87.0 to 89.8% between assays (inter-assay). The coefficients of variation (CV) for intra-assay and inter-assay were 2.09–9.93% and 2.42–12.07%, respectively. These data indicated that the ILFST was highly sensitive and reproducible. Detections of authentic milk samples using ILFST and high-performance liquid chromatography (HPLC) showed no significant differences between the two methods. Hence, the ILFST can be widely used for both qualitative and quantitative detection of DAN residues in milk samples. [ABSTRACT FROM AUTHOR]

In order to investigate the endocrine toxicity of B(a)p to marine polychaete Perinereis aibuhitensis, vitellogenin (VTG) cDNA from the P. aibuhitensis was isolated, recombinated and expressed for the first time. The full length P. aibuhitensis vitellogenin gene (PaVTG) was 5 325 bp, and encoded 1 692 amino acids. It contained the vitellogenin_N domain of unknown function (DUF1943), a von Willebrand factor type D domain, as well as a conserved KALGNAG motif. The expression of VTG gene and protein were mainly up-regulated after exposed to B(a)p at transcriptional and translational levels. PaVTG gene expression did not change significantly at day 4. At day 7 PaVTG expression was up-regulated in 0.5 μg/L and 5 μg/L B(a)p group. At day 14 PaVTG was significantly up-regulated in 0.5–10 μg/L B(a)p. The protein expression of PaVTG in 0.5 μg/L and 10 μg/L B(a)p group was up-regulated with time prolonging, but the expression in 5 μg/L and 50 μg/L B(a)p group exhibited first increased and then decreased trend. With the increasing of B(a)p concentration PaVTG mRNA and protein expression both firstly increased then decreased. In contrast to B(a)p exposure, estradiol did not induce PaVTG gene and protein expression, until late times of exposure (14 d). Overall, the results in this study indicate that PaVTG could be used as a potential indicator of the effects environmental estrogenic compounds. [ABSTRACT FROM AUTHOR]

A lateral flow immunochromatographic strip test (LFIST) based on a competitive format was developed for rapid and sensitive on-site detection of oseltamivir phosphate (OP) residues in poultry product. The sensitivity (half inhibitory concentration, IC50) of the LFIST in the detection of egg and chicken meat samples was confirmed to be 2.56 and 2.63 µg/kg, and the limit detection (LOD) value were 0.43 and 0.42 µg/kg, respectively. For intra-assay and inter-assay reproducibility, recoveries of OP spiked samples ranged between 82.8% and 91.2% with coefficients of variations (CV) less than 5.67% (intra-assay) and 6.52% (inter-assay). The performance of LFIST was comparable to high-performance liquid chromatography (HPLC) in a parallel testing of egg samples and chicken samples. LFIST takes less than 5 minutes, eliminates the dependency on professional personnel, and thus can be used as a surveillance tool for on-site detection of OP residues. [ABSTRACT FROM AUTHOR]