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Zhang, C.-X.

Publications and source records attributed to Zhang, C.-X..

2 recordsLinked to original sources

Whole genome sequencing of 358 brown planthoppers uncovers the landscape of their migration and dispersal worldwide

The brown planthopper (BPH), Nilaparvata lugens, is a serious migratory rice pest, which is distributed in the broad area of the tropical and temperate Asian-Pacific region. However, we know little about key aspects regarding its evolution such as how they diverged and dispersed worldwide. By resequencing and analyzing 358 BPH genomes from 92 populations across the world, we uncover the genetic relationships among their worldwide populations and the history of their global dispersal. We recovered five genetic groups representing the major population structures. Of these, Australian BPHs were shown large genetic divergence with Asian BPHs; two distinct groups have formed in South and Southeast/East Asia that show strong genetic admixture in the southwest border regions of China and west Thailand with Myanmar; two local populations in Bangladesh and Fujian province of China, respectively, unexpectedly separated with surrounding populations. We also find the genetic similarity and closely phylogenetic relationships between majority of East Asian BPHs and Indo-china peninsula BPHs, indicating that Southeast Asia mainland is the major insect sources and overwintering sites for East Asia. Our study provides important molecular evidence to address BPH evolution and other key aspects of its biology such as insecticides resistance and rice varieties virulence.

evolutionary biology

Identification of a female determinant gene for the sexual determination of a hemipteran insect, the brown planthopper

The sex determination mechanism for hemipteran species remains poorly understood. During the sex determination of the brown planthopper (BPH), Nilaparvata lugens, one species of Hemiptera, the functions of doublesex (Nldsx) and NlTra-2 (NlTra-2) genes were identified in our previous studies. Here, we identify an upstream gene for Nldsx in the sex determination cascade, NlFmd, which acts as female determinant gene for N. lugens. The sex-specific transcript of NlFmd (NlFmd-F) encodes an arginine/serine-, and proline-rich protein that is essential for female development. The knockdown of NlFmd resulted in the development of pseudomales, with sex-specific alternative Nldsx processing, and maternal RNA interference (RNAi) against NlFmd generates male-only progeny. Moreover, homologous genes for NlFmd have also been identified in two rice planthopper species, the white-backed planthopper (WBPH, Sogotalla furcifera) and the small brown planthopper (SBPH, Laodelphax striatellus), and these genes appear to be involved in the sex determination cascades for these species. Our data suggest that the sex determination cascade in Delphacidae is conserved.

molecular biology