Development and Evaluation of Improved Strains of Insect Pests for Sterile Insect Technique (SIT) Applications (D42014)
The results of the 5-year Coordinated Research Project were published in a special issue of the peer reviewed journal BMC Genetics
Larvae, pupae and adults from the Anastrepha ludens genetic sexing strain (GSS) Tapachula -7 based on the black pupae (bp) mutation. The males can be identified in the larval stage based on the brown coloration of their anal lobes compared to the black coloration of the females. a) wild-type males. b) black pupae females. Arrows point to the anal lobes [Zepeda-Cisneros et al. BMC Genetics 2014, 15(Suppl 2):S1]
Pest insects represent an enormous burden to agricultural, veterinary and human health aspects in every continent. Their sustainable management is of the utmost importance for the effective utilization of the increasingly limited agricultural resources and for the well-being of humankind. In response to requests from Member States, the Joint FAO/IAEA Insect Pest Control Subprogramme aims to develop, validate and transfer to its Member States environment-friendly technologies to control populations of insect pests and disease vectors including the sterile insect technique (SIT) as a component of area-wide integrated pest management (AW-IPM) programmes.
The SIT has the ability to suppress insect pest populations, or to prevent, contain or even eradicate the establishment of new outbreaks of invasive pests. The operational use of the SIT in AW-IPM programmes continues to increase and there are currently several active programmes in almost all continents against agricultural pests, mainly fruit flies and lepidopteran (moth) pests, but also other agricultural pests or disease vectors of livestock and humans. However, managers have indicated that programme efficiency can still be considerably enhanced when certain components of the technology are improved such as, for example, the availability of genetic sexing strains (GSS) against new target species or the development of strains carrying genetic markers which would allow the differentiation of released sterile insects from wild populations.
To address these gaps, the Joint FAO/IAEA Insect Pest Control Subprogramme initiated the Coordinated Research Project (CRP D42014) “Development and Evaluation of Improved Strains of Insect Pest for SIT applications”. The activities of this CRP focused on four main areas: (1) insect genetics and transformation, (2) sex determination, (3) development of novel sexing systems and (4) improvement and evaluation of existing strains for SIT applications.
Major achievements of this CRP include the development and characterization of new GSS suitable for SIT applications against major agricultural pests such as the Mexican fruit fly, Anastrepha ludens and the carambola fly, Bactrocera carambolae. Another major achievement was the development and evaluation of male-only strains of the Australian sheep blowfly, Lucilia cuprina, using modern biotechnology approaches.
One important issue is to compare the performance of strains developed or produced by classical genetic, transgenic and symbiont-based approaches to a level where a decision can be made as to their suitability to produce high-quality sterile males for use in large scale SIT programmes. This will be addressed in the next CRP (D4.20.16) “Comparing rearing efficiency and competitiveness of sterile male strains produced by genetic, transgenic or symbiont-based technologies” (2015-2020). Major beneficiaries will be operational AW-IPM programmes in Member States that apply the SIT against these major insect pests.
Researchers from Argentina, Australia, China, Czech Republic, Germany, Guatemala, Greece, India, Italy, Mexico, Spain, Thailand and USA participated in this CRP.
Figure: Crossing scheme for the isolation of genetic sexing strains in Anastrepha ludens. X and Y: represent the sex chromosomes. bp+: represents the autosome harboring the wild type allele for the brown pupae color. bp: represents the autosome harboring the black pupae (bp) mutation. Y-2 and 2-Y: represent the two new chromosomes following the translocation event [Zepeda-Cisneros et al. BMC Genetics 2014, 15(Suppl 2):S1].