Phthalate esters (PAEs) are an emerging pollutant due to widespread distribution in environmental mediums that have attracted widespread attention over recent years.  However, there is little information about tea plantation soil PAEs.  A total of 270 soil samples collected from 45 tea plantations in the major high-quality tea-producing regions of Jiangsu, Zhejiang, and Anhui provinces in China were analyzed for seven PAEs.  The detection frequency of PAEs in tea plantation soil was 100%.  DBP, DEHP, and DiBP were the main congeners in tea plantation soil.  The PAEs concentrations in the upper soil were significantly higher than those in the lower soil.  The concentration of tea plantation soil PAEs in Jiangsu Province was significantly lower than those in Zhejiang and Anhui provinces.  Intercropping with chestnuts can effectively reduce the contamination level of PAEs in tea plantation soil.  Correlation analysis, redundancy analysis, partial correlation analysis, and structural equation modeling methods further confirmed the strong direct influence of factors such as chestnut–tea intercropping, temperature, and agricultural chemicals on the variation of PAEs in tea plantation soil.  The health and ecological risk assessments indicated that non-carcinogenic risk was within a safe range and that there was a high carcinogenic risk via the dietary pathway, with DBP posing the highest ecological risk. 

PLATZ is a novel zinc finger DNA-binding protein that plays an important role in regulating plant growth and development and resisting abiotic stress.  However, there has been very little research on the function of this family gene in tomatoes, which limits its application in germplasm resource improvement.  Therefore, the PLATZ gene family was identified and analyzed in tomato, and its roles were predicted and verified to provide a basis for in-depth research on SlPLATZ gene function.  In this study, the PLATZ family members of tomato were identified in the whole genome, and 19 SlPLATZ genes were obtained.  Functional prediction was conducted based on gene and promoter structure analysis and RNA-seq-based expression pattern analysis.  SlPLATZ genes that responded significantly under different abiotic stresses or were significantly differentially expressed among multiple tissues were screened as functional gene resources.  SlPLATZ17 was selected for functional verification by experiment-based analysis.  The results showed that the downregulation of SlPLATZ17 gene expression reduced the drought and salt tolerance of tomato plants.  Tomato plants overexpressing SlPLATZ17 had larger flower sizes and long, thin petals, adjacent petals were not connected at the base, and the stamen circumference was smaller.  This study contributes to understanding the functions of the SlPLATZ family in tomato and provides a reference for functional gene screening.

The host intestinal microbiota has emerged as the third element in the interactions between hosts and enteric viruses, and potentially affects the infection processes of enteric viruses. However, the interaction of porcine enteric coronavirus with intestinal microorganisms during infection remains unclear. In this study, we used 16S-rRNA-based Illumina NovaSeq high-throughput sequencing to identify the changes in the intestinal microbiota of piglets mediated by porcine epidemic diarrhea virus (PEDV) infection and the effects of the alterations in intestinal bacteria on PEDV infection and its molecular mechanisms. The intestinal microbiota of PEDV-infected piglets had significantly less diversity than the healthy group and different bacterial community characteristics. Among the altered intestinal bacteria, the relative abundance of Clostridium perfringens was significantly increased in the PEDV-infected group. A strain of C. perfringens type A, named DQ21, was successfully isolated from the intestines of healthy piglets. The metabolites of swine C. perfringens type A strain DQ21 significantly enhanced PEDV replication in porcine intestinal epithelial cell clone J2 (IPEC-J2) cells, and PEDV infection and pathogenicity in suckling piglets. Palmitic acid (PA) was identified as one of those metabolites with metabolomic technology, and significantly enhanced PEDV replication in IPEC-J2 cells and PEDV infection and pathogenicity in suckling piglets. PA also increased the neutralizing antibody titer in the immune sera of mice. Furthermore, PA mediated the palmitoylation of the PEDV S protein, which improved virion stability and membrane fusion, thereby enhancing viral infection. Overall, our study demonstrates a novel mechanism of PEDV infection, with implications for PEDV pathogenicity.

Cold stress widely impairs the quality and yield of tea plants. The miR164 family and its target NAC transcription factor have been identified as crucial regulators in response to cold stress. However, the role of miR164 and CsNAC in cold tolerance in tea plants was little understood. In our study, the expression level of csn-miR164a was significantly reduced under cold stress, and was significantly negative correlation with that of CsNAC1. 5’ RACE and GUS histochemical assays clearly showed that CsNAC1 was specifically cleaved by csn-miR164a. The csn-miR164a-silenced tea leaves promoted expression level of CsNAC1 and CsCBFs, and exhibited greater cold tolerance, also overexpression of CsNAC1 enhanced cold tolerance in transgenic Arabidopsis plants by promoting the expression levels of AtCBFs. In contrast, the heterologous overexpression of csn-miR164a in Arabidopsis decreased the expression level of AtNACs and AtCBFs, and thus impaired cold tolerance. Additionally, silencing of CsNAC1-impaired the expression levels of CsCBFs resulted in greater cold sensitivity in tea leaves. Taken together, our present study demonstrated that the miR164a-CsNAC1 module may play a negative role in cold tolerance of tea plants via CsCBF-dependent pathway.

Nitrogen (N) and potassium (K) are key elements for crop growth, yet exhaustive research on the impact of N–K interactions on plant N and K status and yield is lacking.  This study aimed to explore effective indicators for diagnosing N and K nutrition and predicting yield of wheat under N–K interactions based on the theoretical framework of a critical nutrient dilution curve.  A four-year N–K interaction experiment involving three wheat cultivars was employed for building and validating nutrient indices (NIs) based on the critical N dilution curve (CNDC) and the critical K dilution curve (CKDC).  In addition, literature data were collected for supplementary validation.  The results revealed that the changes of parameter A1 in critical K dilution curves (CKDCs) can reflect the impact of nitrogen application on K absorption and utilization.  However, the difference in KNI values calculated by CKDC under different N levels is not significant. Based on the aboveground biomass (AGB), a universal CKDC was established and defined as Kc=3.63AGB^–0.37 under N–K interactions.  The results showed that the direct effects of N or K deficiency on crops could be quantified by the N–K interaction index (NKI) calculated by integrating CNDC and CKDC, and the changes in crop growth in response to proportional N and K concentrations could be determined by NKI as well.  In addition, topdressing N fertilizer at the jointing stage significantly improved the N–K interaction effect on N nutrition index (NNI) and NKI at the booting stage (P<0.05), but had no significant N–K interaction effect on K nutrition index (KNI).  All indicators at heading stage demonstrated the best predictive capability for relative yield (RY) than other stages.  Compared with NNI and KNI, the prediction accuracy of yield with NKI improved by 11.63 and 17.44%, respectively.  The NKI has better performance in diagnosing N and K nutrition and predicting yield under N–K interactions than NNI and KNI.  This result enhances the interpretation of the effects of N–K interactions on wheat growth and has important applications in improving the accuracy of N and K nutrition diagnosis and yield prediction.