Spodoptera frugiperda (S. frugiperda) is an invasive pest that threatens global crop production and food security and poses a serious threat to maize production worldwide. Metal–organic framework (MOF) nanocarriers have great potential for agricultural pest control applications. The present study successfully prepared the chemical cross-linking of iron-based metal–organic framework nanoparticles (MIL-101(Fe)-NH2 NPs) with sodium lignosulfonate (SL) as a pH/laccase double stimuli-responsive pesticide release system. The average particle size of the prepared chlorfenapyr (CF)-loaded nanoparticles (CF@MIL-101-SL NPs) was 161.54 nm, and the loading efficiency was 44.52%. Bioactivity assays showed that CF@MIL-101-SL NPs increased the toxicity of CF to S. frugiperda and caused the rupture of the peritrophic membrane and enlargement of the midgut. Data from 16S rRNA gene sequencing showed that CF@MIL-101-SL treatment reduced the resistance of S. frugiperda to pesticides and pathogens and affected nutrient and energy availability by remodeling the intestinal microbiota of S. frugiperda. The dysregulated microbial community interacted with the broken peritrophic membrane, which exacerbated damage to the host. Nontargeted metabolomic results showed that ABC transporters may be a potential mechanism for the enhanced toxicity of CF@MIL-101-SL to S. frugiperda. In summary, the present study provides effective strategies for toxicological studies of nanopesticides against insects.
Resistance to succinate dehydrogenase inhibitors (SDHI) in Botrytis cinerea is associated with point mutations in the target gene succinate dehydrogenase subunit B ( SdhB ). The substitution from histidine to arginine at codon 272 (H272R) is currently the predominant mutation in SDHI-resistant populations in B. cinerea worldwide. In order to monitor the development of resistance to SDHI, a rapid, simple, and efficient method with high specificity to the H272R point mutation was developed based on loop-mediated isothermal amplification (LAMP). To specifically detect the H272R mutation, a set of four primers was designed based on the sequence of SdhB , and the LAMP reaction was optimized. When SYBR Green I was added after reaction, only samples with the H272R mutation showed the color change (from brown to fluorescent yellow), indicating that this set of primers could successfully discriminate the H272R genotype from other genotypes. Specificity and accuracy tests showed that this LAMP assay had high specificity and accuracy. Moreover, the LAMP method was further simplified with fungal mycelia and conidia as the amplification template which could be prepared within 5 min. Due to the low cost, simplicity, high efficiency, and specificity, the developed LAMP assay may contribute to the monitoring of resistance development to SDHI in B. cinerea , especially in field and high-throughput experiments.
危险品化学品经营许可证（带存储）