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Abstract The brown planthopper (BPH) is one of the most problematic pests affecting rice (Oryza sativa L.) yields in Asia. Breeding rice varieties containing resistance genes is the most economical and effective means of controlling BPH. In this study, the key factors in resistance to BPH were investigated between the high-resistance rice variety “R26” and the susceptible variety “TN1” using RNA-sequencing. We identified 9527 differentially expressed genes (DEGs) between the rice varieties under BPH-induced stress. Weighted time-course gene co-expression network analysis (WGCNA) indicated that the increased expression of genes is associated with plant hormones, MAPK signaling pathway and biosynthesis of other secondary metabolites, which were involved in disease resistance. A connection network identified a hub gene, OsREM4.1 (BGIOSGA024059), that may affect rice resistance to the BPH. Knocking out OsREM4.1 in rice can lead to a decrease in callose, making it less resistant to BPH. Overall, the expression of differentially expressed genes varies among rice varieties with different resistance in BPH invasion. Inaddition, R26 enhances resistance to BPH by upregulating genes and secondary metabolites related to stress resistance and plant immunity. In summary, our study provides valuable insights into the genome-wide expression profile of DEGs in rice under BPH invasion through high-throughput sequencing, and further suggests that R26 can be used to develop high resistance rice lines in BPH resistant breeding programs.

The diversity of root endophytic microorganisms, which is closely related to plant life activities, is known to vary with the plant growth stage. This study on the ratooning rice Jiafuzhan explored the diversity of the root endophytic bacteria and fungi and their dynamics during the plant life cycle. By sequencing the 16S ribosomal ribonucleic acid (16S rRNA) and internal transcribed spacer (ITS) genes, 12,154 operational taxonomic units (OTUs) and 497 amplicon sequence variants (ASVs) were obtained, respectively. The root endophytic microorganisms of rice in the seedling, tillering, jointing, heading, and mature stages of the first crop and at 13, 25, and 60 days after regeneration (at the heading, full heading, and mature stages of the second crop, respectively) were analyzed using diversity and correlation analyses. There were significant differences in the α-diversity and β-diversity of root endophytic bacteria and fungi in the growth stage. Additionally, linear discriminant analysis (LDA) effect size (LEfSe) analysis revealed biomarker bacteria for each growth stage, but biomarker fungi did not exist in every stage. Moreover, the correlation analysis showed that the bacterial and fungal biomarkers interacted with each other. Furthermore, the nitrogen-fixing genus Bradyrhizobium existed in all growth stages. These findings indicate the pattern of root endophytic microorganisms of ratooning rice at different growth stages, and they provide new insights into the high yield of the second crop of ratooning rice (in light of the abundance of various bacteria and fungi).

Background: Ectopic pregnancy (EP) refers to the implantation of the zygote outside the uterine cavity. In clinical practice, the diagnosis of EP relies on a combination of ultrasound findings and serum human chorionic gonadotrophin (hCG) measurements. However, the need for serial hCG measurements increases the risk of tubal rupture and death, underscoring the need to identify biomarkers for the early detection of EP. Methods: The serum concentrations of 21 microRNAs (miRNAs) associated with pregnancy or with known placental expression, as well as serum hCG and progesterone levels were analyzed 36 patients with viable intrauterine pregnancy (VIP), 30 patients with spontaneous abortion (SA), and 34 patients with EP using specific assay kits and reverse transcription PCR. The diagnostic performance of the different serum markers for detecting EP was analyzed by ROC curve analysis. Results: Five miRNAs were differentially expressed between the three groups, of which miR-873 and miR-223 were significantly lower in EP than in VIP and SA patients and did not change significantly according to gestational age, and miR-323 was significantly higher in EP than in VIP and SA. As a single marker, miR-873 had the highest sensitivity for detecting EP at 61.76% (at a fixed specificity of 90%). In comparison, the combination of hCG, progesterone and miR-873 had the highest sensitivity for detecting EP at 79.41% (at a fixed specificity of 90%). Conclusion: Although further validation in large-scale prospective studies is necessary, our results suggest that miR-873 could be a valuable noninvasive and stable biomarker for the early detection of EP.