CRISPR/Cas9-mediated mutagenesis of the white-eye gene in the tephritid pest Bactrocera zonata

Abstract

Bactrocera zonata is a highly invasive agricultural pest that causes extensive damage to fruit crops. The Sterile Insect Technique (SIT), a species-specific and environmentally friendly pest control method, significantly benefits from the availability of Genetic Sexing Strains (GSSs) that enable efficient mass production of males for sterile release. However, no GSS currently exists for B. zonata limiting SIT applications targeting this important invasive pest. Here, we report two key advancements toward GSS development in this species. First, we present a high-quality, chromosome-level genome assembly from male B. zonata, identifying two scaffolds derived from the Y chromosome, which represent potential targets for future male-specific genetic engineering. Second, we demonstrate the feasibility of CRISPR/Cas9 genome editing in B. zonata by generating stable, homozygous white-eye mutants through targeted disruption of the conserved white-eye gene. This visible, recessive phenotype serves as a proof-of-concept for developing selectable markers in this species. Together, these results provide foundational genomic and genetic tools to support the development of GSSs in B. zonata, advancing the potential for sustainable, genetics-based pest control strategies.

Keywords

Bactrocera zonata / CRISPR/Cas9 / genetic sexing strain / sterile insect technique / tephritidae / white eye

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2025 The Author(s). Insect Science published by John Wiley & Sons Australia, Ltd on behalf of Institute of Zoology, Chinese Academy of Sciences.