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The silkworm (Bombyx mori) is an important model lepidopteran insect and can be used to identify pesticide resistance‐related genes of great significance for biological control of pests. Uridine diphosphate glucosyltransferases (UGTs), found in all organisms, are the main secondary enzymes involved in the metabolism of heterologous substances. However, it remains uncertain if silkworm resistance to fenpropathrin involves UGT. This study observes significant variations in BmUGT expression among B. mori strains with variable fenpropathrin resistance post‐feeding, indicating BmUGT's role in fenpropathrin detoxification. Knockdown of BmUGT with RNA interference and overexpression of BmUGT significantly decreased and increased BmN cell activity, respectively, indicating that BmUGT plays an important role in the resistance of silkworms to fenpropathrin. In addition, fenpropathrin residues were significantly reduced after incubation for 12 h with different concentrations of a recombinant BmUGT fusion protein. Finally, we verified the conservation of UGT to detoxify fenpropathrin in Spodoptera exigua: Its resistance to fenpropathrin decreased significantly after knocking down SeUGT. In a word, UGT plays an important role in silkworm resistance to fenpropathrin by directly degrading the compound, a function seen across other insects. The results of this study are of great significance for breeding silkworm varieties with high resistance and for biological control of pests. [ABSTRACT FROM AUTHOR]

In order to realize the resource utilization of calcite tailings corner waste, block copolymerized polypropylene (PPB)/polyolefin elastomer (POE)/calcite waste powder ternary composites were prepared by melt blending modified extrusion method. The effects of waste powder content and POE content on mechanical properties, thermal properties and microstructure of composites were investigated. The results show that POE can improve compatibility of composites, and calcite waste powder can significantly enhance stiffness. Adding 10 phr of calcite waste powder and 20 phr of POE to the PPB base material can improve compatibility between inorganic filler and resin substrate and significantly improve mechanical properties of composites. The impact strength of composites is increased to 55.48 kJ/m2 by the coordination of calcite waste powder and POE. POE and calcite waste powder both reduce the crystallinity of composites, have little effect on melting temperature, and slightly increase crystallization temperature. PPB, POE and calcite waste powder are compounded to prepare composites, which provided a new way to solve the application problem of calcite tailings. [ABSTRACT FROM AUTHOR]