CRISPR/Cas9 Mutagenesis to Generate Novel Traits in Bactrocera tryoni for Sterile Insect Technique.

Sterile Insect Technique (SIT) is a biocontrol strategy that has been widely utilized to suppress or eradicate outbreak populations of insect pests such as tephritid fruit flies. As SIT is highly favored due to it being species-specific and environmentally friendly, there are constant efforts to improve the efficiency and efficacy of this method in particular at low pest densities; one of which is the use of genetically enhanced strains. Development of these desirable strains has been facilitated by the emergence of the CRISPR/Cas genome-editing technology that enables the rapid and precise genomic modification of non-model organisms.

Patterns of sperm use by twice-mated female Queensland fruit flies.

Multiple mating by females, polyandry, is common in insects, including in tephritid fruit flies. Female insects that remate commonly store sperm of multiple males. How the sperm of different males contribute to paternity is an important element of sexual selection.

Lessons from Drosophila: Engineering Genetic Sexing Strains with Temperature-Sensitive Lethality for Sterile Insect Technique Applications.

A major obstacle of sterile insect technique (SIT) programs is the availability of robust sex-separation systems for conditional removal of females. Sterilized male-only releases improve SIT efficiency and cost-effectiveness for agricultural pests, whereas it is critical to remove female disease-vector pests prior to release as they maintain the capacity to transmit disease. Some of the most successful Genetic Sexing Strains (GSS) reared and released for SIT control were developed for Mediterranean fruit fly (Medfly), , and carry a temperature sensitive lethal () mutation that eliminates female but not male embryos when heat treated.

White pupae phenotype of tephritids is caused by parallel mutations of a MFS transporter.

Mass releases of sterilized male insects, in the frame of sterile insect technique programs, have helped suppress insect pest populations since the 1950s. In the major horticultural pests Bactrocera dorsalis, Ceratitis capitata, and Zeugodacus cucurbitae, a key phenotype white pupae (wp) has been used for decades to selectively remove females before releases, yet the gene responsible remained unknown. Here, we use classical and modern genetic approaches to identify and functionally characterize causal wp mutations in these distantly related fruit fly species.

Identification of Y-chromosome scaffolds of the Queensland fruit fly reveals a duplicated gyf gene paralogue common to many Bactrocera pest species.

Bactrocera tryoni (Queensland fruit fly) are polyphagous horticultural pests of eastern Australia. Heterogametic males contain a sex-determining Y-chromosome thought to be gene poor and repetitive. Here, we report 39 Y-chromosome scaffolds (~700 kb) from B.