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Development and Evaluation of Improved Strains of Insect Pests for SIT
Closed for proposals
Project Type
Project Code
D42014CRP
1517Approved Date
Status
Start Date
Expected End Date
Completed Date
6 May 2014Description
The application of the Sterile Insect Technique (SIT) in area-wide integrated pest management (AW-IPM) programmes continues to increase in response to requests from Member States. However, programme efficiency can still be considerably enhanced when certain components of the technology are improved, such as the development of improved strains for mass rearing and release. These include strains that 1) produce only male insects for sterilization and release and 2) carry easily identifiable markers to identify released sterile insects in the field. Using both classical and modern biotechnology techniques, key insect pests will be targeted, where SIT programmes are being implemented. The pests include mosquitoes, the Mexican fruit fly, the codling moth, the oriental fruit fly and the pink bollworm. This CRP will develop and evaluate these new strains to a level where a decision can be made as to their suitability for use in large scale SIT programmes. Major beneficiaries will be operational AW-IPM programmes in MS that apply the SIT against major insect pests. By the end of the CRP several genetically marked sexing strains will be available. The construction/evaluation of such strains through this CRP will have the following tangible benefits for the pest control programmes in MS using SIT:
1.) As only the males are needed for the SIT, the production, handling and release costs can be reduced significantly if sexing strains are used.
2.) A considerable proportion of the cost for SIT programmes is used for the monitoring sterile insects in the field and therefore a genetic marking system for the released flies will reduce costs considerably.
3.) Male-only releases are several fold more efficient than releases of both sexes. Consequently, when the genetic sexing technology is available SIT programmes are significantly more efficient and therefore more cost effective.
4.) Mosquito SIT without genetic sexing strains is impossible; i.e. the availability of such genetic sexing strains expands the application of SIT into this important group of pest species
Objectives
The overall objective of the CRP was to increase efficiency of operational SIT programs for key insect pests through the provision of improved strains for mass rearing and release
Specific objectives
To apply existing technologies (classical genetics and/or molecular approaches) for the development of sexing strains in key insect pests
To develop and integrate molecular and genetic marker strains to monitor released insects in the field, to tag transgenes and to determine the mating status of females in the field
To develop strains with stabilized vectors integrated at targeted insertion sites to expand the safe and effective use of improved strains for SIT
To encourage and attract participants to the CRP in the field of lepidopteran genetics
Impact
The CRP expanded the list of key insect species for which genetic sexing strains are available and suitable for sterile insect technique applications in MS upon request. The list now includes, in addition to C. capitata and B. cucurbitae, the species B. dorsalis (strain Salaya 1), B. carambolae, B. correcta, Anastrepha ludens and A. suspensa. Also, CRP members developed and integrated molecular and genetic markers to monitor released insects in the field, to tag transgenes and to determine the mating status of females in the field. Marked strains have been developed for C. capitata, Bactrocera (B. dorsalis and B. tryoni) and Anastrepha (A. ludens and A. suspensa) species. A sperm ID method was developed for the Vienna-8 genetic sexing strain of C. capitata which is currently in use in mass rearing facilities and SIT programs worldwide. Strains with stabilized vectors integrated at targeted insertion sites were developed to be able to assess the potential of the safe and effective use of transgenic strains. The CRP also recruited experts in the field of lepidopteran genetics and made significant progress towards understanding the genetics of some moth pests.
Relevance
The results of the CRP are very relevant for operational SIT Programs for key insect pests through the development of improved strains for mass rearing and release. For example, transgenic sexing strains have been developed for two tephritid and two calliphorid insect pests. In addition, the medfly GSS has been marked with stable fluorescent markers and classical genetic sexing strains have been developed for the fruit flies A. ludens, B. dorsalis and B. carambolae. The technology developed during this CRP could be transferred to other insect pests. Moreover, the capabilities and genomic resources developed by several members of the CRP will facilitate a better understanding of the biology of pest insects and provide a valuable resource for future strain development. The goal is to improve the technology and ultimately the field implementation of SIT projects as well as effective transfer of technology and capacity building.