A New Diagnostic Resource for Ceratitis capitata Strain Identification Based on QTL Mapping

Area of Science:

• Agricultural Entomology
• Genetics
• Pest Management

Background:

• The Mediterranean fruit fly (Ceratitis capitata) is a significant agricultural pest, necessitating effective control strategies like the sterile insect technique (SIT).
• Accurate discrimination between released sterile males and wild flies is crucial for detecting rare invasive individuals in SIT release areas.

Purpose of the Study:

• To develop a reliable genotyping assay for differentiating sterile male Mediterranean fruit flies from wild populations.
• To identify genetic markers linked to traits used in SIT programs, specifically white pupae (wp) and temperature-sensitive lethal (tsl).

Main Methods:

• Utilized Quantitative Trait Locus (QTL) mapping to identify single nucleotide polymorphisms (SNPs) associated with wp and tsl traits.
• Developed a genotyping assay based on a specific SNP found to be in near-perfect linkage disequilibrium with the pupal color phenotype.
• Genotyped individuals from various SIT colonies and wild populations across the geographic range.

Main Results:

• Identified a single SNP strongly correlated with the white pupae phenotype, enabling reliable discrimination of SIT flies.
• The developed genotyping assay demonstrated consistency in identifying SIT flies across different colonies and wild populations.
• QTL mapping provided foundational insights into the genetic basis of traits facilitating male-only releases.

Conclusions:

• The developed SNP-based genotyping assay offers a definitive method for distinguishing sterile SIT flies from wild Mediterranean fruit flies.
• This genetic tool enhances the effectiveness of SIT programs by improving the detection of invasive individuals.
• The genetic mapping of wp and tsl traits can inform the development of SIT strategies for related pest species.