The Anopheles arabiensis genetic sexing strain ANO IPCL1 and its application potential for the sterile insect technique in integrated vector management programmes

Abstract Anastrepha ludens (Loew) (Diptera: Tephritidae) is an endemic pest of Mexico, attacking several fruits of economic importance. The Sterile Insect Technique (SIT), consisting of mass-rearing, irradiation and release of adults, is used to control this pest in affected areas. Currently, a genetic sexing strain (Tapachula 7, Tap-7) consisting only of A. ludens males is being released, yet we lack information on its sexual performance at the early ages when they are released and on its post copulatory behavior in terms of sperm transfer and mating inhibition. Here, sexual competitiveness at young ages and ability to inhibit female re-mating was compared between sterile Tap-7, Standard Bisexual (SB), or wild males both in laboratory and field cage conditions. Sperm stored by females mating with wild, Tap-7, or SB strain males was also compared. Six-day-old sterile Tap-7 males had low mating rates, however, by 7 d of age 80% of males had mated. Tap-7 males were just as likely as wild males to inhibit wild female re-mating. In field cages, sterile Tap-7 males mated faster than wild and sterile males from the SB strain and had comparable mating success to wild males. Females mated to sterile Tap-7 males stored more sperm than those mated to sterile SB males. Females mated to wild males stored more sperm than females mated to any other type of male. Mass-rearing had a greater effect on decreasing sperm stored by females than irradiation. We recommend continuing the release of the GSS strain of A. ludens.

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A Novel Genetic Sexing Strain of Anastrepha Ludens for Cost-Effective Sterile Insect Technique Applications: Improved Genetic Stability and Rearing Efficiency

Insects ◽

10.3390/insects12060499 ◽

2021 ◽

Vol 12 (6) ◽

pp. 499

Author(s):

Edwin Ramírez-Santos ◽

Pedro Rendon ◽

Georgia Gouvi ◽

Antigone Zacharopoulou ◽

Kostas Bourtzis ◽

...

Keyword(s):

Genetic Stability ◽

Sterile Insect Technique ◽

Production Efficiency ◽

Small Scale ◽

Management Approach ◽

Anastrepha Ludens ◽

Male Mating ◽

Pest Species ◽

Genetic Sexing ◽

Genetic Sexing Strain

Anastrepha ludens (Loew) is one of the most destructive insect pests damaging several fruits of economic importance. The sterile insect technique (SIT) is used under an area-wide integrated pest management approach, to suppress these pest populations. Mass rearing facilities were initially established to produce sterile males of bi-sexual strains in support of SIT. The first genetic sexing strain (GSS) for A. ludens, Tapachula-7, based on pupal color dimorphism, was a key development since the release of males-only significantly increases the SIT efficiency. In this study, we document the development of a novel pupal color-based GSS. Twelve radiation-induced translocation lines were assessed as potential GSS in terms of recombination rates and rearing efficiency at a small scale. The best one, GUA10, was cytogenetically characterized: it was shown to carry a single translocation between the Y chromosome and chromosome 2, which is known to carry the black pupae marker. This GSS was further evaluated at medium and large scales regarding its genetic stability, productivity and quality versus Tapachula-7. GUA10 presented better genetic stability, fecundity, fertility, production efficiency, flying ability, and male mating, clear indicators that GUA10 GSS can significantly improve the efficacy and cost-effectiveness of SIT applications against this pest species.

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Improving the Phenotypic Properties of the Ceratitis capitata (Diptera: Tephritidae) Temperature-Sensitive Lethal Genetic Sexing Strain in Support of Sterile Insect Technique Applications

Journal of Economic Entomology ◽

10.1093/jee/toaa220 ◽

2020 ◽

Vol 113 (6) ◽

pp. 2688-2694

Author(s):

Mitzy F Porras ◽

Jose S Meza ◽

Edwin G Rajotte ◽

Kostas Bourtzis ◽

Carlos Cáceres

Keyword(s):

High Temperatures ◽

Temperature Sensitivity ◽

Larval Stage ◽

Sterile Insect Technique ◽

Ceratitis Capitata ◽

Temperature Sensitive ◽

Genetic Sexing ◽

Phenotypic Properties ◽

Slow Development ◽

Genetic Sexing Strain

Abstract The genetic sexing strain (GSS) of the Mediterranean fruit fly (Ceratitis capitata (Wiedemann)) Vienna 8D53− is based on a male-linked translocation system and uses two selectable markers for male-only production, the white pupae (wp) and the temperature sensitivity lethal (tsl) genes. In this GSS, males emerge from brown pupae and are resistant to high temperatures while females emerge from white pupae, are sensitive to high temperatures. However, double homozygous females (wp tsl/wp tsl) exhibit a slower development rate compared to heterozygous males (wp+tsl+/wp tsl) during the larval stage, which was attributed to the pleiotropic effects of the tsl gene. We present the first evidence that this slower development is due to a different gene, here namely slow development (sd), which is closely linked to the tsl gene. Taking advantage of recombination phenomena between the two loci, we report the isolation of a novel temperature sensitivity lethal strain using the wp mutation as a morphological marker, which showed faster development (wp tsl FD) during the larval stage and increased in its temperature sensitivity compared with the normal tsl strain. Moreover, the introgression of this novel wp tsl FD combined trait into the Vienna 8D53− GSS, resulted in a novel Vienna 8D53− FD GSS, where females showed differences in the thermal sensibility, larval development speed, and productivity profiles. The modification of these traits and their impact on the mass rearing of the GSS for sterile insect technique applications are discussed.

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Sterile Insect Technique in an Integrated Vector Management Program against Tiger Mosquito Aedes albopictus in the Valencia Region (Spain): Operating Procedures and Quality Control Parameters

Insects ◽

10.3390/insects12030272 ◽

2021 ◽

Vol 12 (3) ◽

pp. 272

Author(s):

Carlos Tur ◽

David Almenar ◽

Sandra Benlloch-Navarro ◽

Rafael Argilés-Herrero ◽

Mario Zacarés ◽

...

Keyword(s):

Quality Control ◽

Aedes Albopictus ◽

Sterile Insect Technique ◽

Management Program ◽

World Health ◽

Integrated Vector Management ◽

Control Parameters ◽

Medium Scale ◽

Vector Management ◽

Quality Control Parameters

Aedes albopictus and Aedes aegypti are the main vectors of arboviral diseases such as dengue, Zika and chikungunya viruses. About a third of the world population is currently at risk of contracting Aedes-borne epidemics. In recent years, A. albopictus has drastically increased its distribution in many countries. In the absence of efficient mosquito vector control methods, the sterile insect technique (SIT) is presented as a very promising and environment-friendly control tool. The Agriculture Department of the Valencian Region is promoting an ongoing pilot project to evaluate the efficacy of an integrated vector management program (IVM) based on the use of the SIT as the main method of control. The laboratory studies for evaluating the entomological efficacy of SIT through the phased conditional testing process recommended by World Health Organization and the International Atomic Energy Agency (WHO-IAEA) are addressed. This study describes the routine operating procedures and quality control parameters for the medium-scale rearing of sterile male A. albopictus. More than 15 million sterile males have been produced and released in an area of 80 ha between 2018 and 2020. Of the initial L1 larvae, we recovered 17.2% of male pupae after sex sorting to be sterilized and released on the field, while the rest of the pupae remained available to maintain the rearing colony. The residual percentage of females after sex sorting was on average 0.17%. The obtained values in terms of production and quality control as well as the proposed rearing methodology can be useful for designing a medium-scale mosquito-rearing pipeline.

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