The whitefly (Bemisia tabaci), an important invasive pest that causes severe damage to crops worldwide, has developed resistance to a variety of insecticides. Carboxylesterases (COEs) are important multifunctional enzymes involved in the growth, development, and xenobiotic metabolism of insects. However, systematic studies on the COEs of B. tabaci are scarce. Here, 42 putative COEs in different functional categories were identified in the Mediterranean species of B. tabaci (B. tabaci MED) based on a genome database and neighbor-joining phylogeny. The expression patterns of the COEs were affected by the development of B. tabaci. The expression levels of six COEs were positively correlated with the concentration of imidacloprid to which B. tabaci adults were exposed. The mortality of B. tabaci MED adults fed dsBTbe5 (67.5%) and dsBTjhe2 (58.4%) was significantly higher than the adults fed dsEGFP (41.1%) when treated with imidacloprid. Our results provide a basis for functional research on COEs in B. tabaci and provide new insight into the imidacloprid resistance of B. tabaci.

Nitrogen is an essential element for all life on earth. Nitrogen metabolism, including excretion, is essential for growth, development, and survival of plants and animals alike. Several nitrogen metabolic processes have been described, but the underlying molecular mechanisms are unclear. Here, we reveal a unique process of nitrogen metabolism in the whitefly Bemisia tabaci , a global pest. We show that it has acquired two bacterial uricolytic enzyme genes, B. tabaci urea carboxylase ( BtUCA ) and B. tabaci allophanate hydrolase ( BtAtzF ), through horizontal gene transfer. These genes operate in conjunction to not only coordinate an efficient way of metabolizing nitrogenous waste but also control B. tabaci ’s exceptionally flexible nitrogen recycling capacity. Its efficient nitrogen processing explains how this important pest can feed on a vast spectrum of plants. This finding provides insight into how the hijacking of microbial genes has allowed whiteflies to develop a highly economic and stable nitrogen metabolism network and offers clues for pest management strategies.

Soybean aphid (Aphis glycines) is one of the main pests on soybeans, which causes serious damage to the soybean worldwide. The current genome of the soybean aphid is quite fragmented, which has impeded scientific research to some extent. In this study, we assembled a chromosome-level genome of the soybean aphid using MGI short reads, PacBio HiFi long reads and Hi-C reads. The genome sequence was anchored to four pseudo-chromosomes, with a total genome length of 324 Mb and a scaffold N50 length of 88.85 Mb. We evaluated the genome based on insecta_odb10 and the results show it has a completeness of 97.2%. A total of 20,781 protein-coding genes were predicted in the genome, of which 17,183 genes were annotated in at least one protein database. Our work provides a new genomic resource for the soybean aphid study.