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Improving the quality of European citrus & fruit by developing Medfly SIT technology so it can be widely applied in Europe

Final Report Summary - CLEANFRUIT (Improving the quality of European citrus & fruit by developing Medfly SIT technology so it can be widely applied in Europe)

The main aim of the CLEANFRUIT project was to develop safer, higher quality food by implementing improved crop protection systems based on the increasingly spread of Sterile insect technique (SIT) in Europe. The project consisted of into 34 deliverables, a brief overview of which is stated below:

Deliverable 1: Optimised storage system for adults for release
The time from adult emergence until the sterile fly is released in the field is critical. The objective was to address key areas of storage that would improve sterile fly performance in the field. Three new tests, in addition to the standard mating performance field cage test, provided versatile and useful tools for optimising conditions in which sterile flies are held until their release.

Deliverable 2: Information material and functional website for dissemination of SIT
One of the main dissemination tools that was developed was the CLEANFRUIT website, which covers all aspects of current SIT knowledge.

Deliverable 4: SIT implementation manual
CLEANFRUIT compiled, translated and published on the web a 'Manual on SIT Implementation', designed to guide and inform potential promoters of SIT programmes.

Deliverables 3 and 12: Functional egg shipping container and final egg shipping container
Decentralisation of sterile medfly male production was an effective way to apply sterile insect technique against this insect pest in European agricultural conditions. To establish this novel approach, an effective and safe egg transportation system from centralised egg production facilities to satellite male only production facilities was developed.

Deliverable 5: Optimised chilling technology / protocol
A protocol was recommended for use in SIT programmes using ground or aerial releases that require the transfer of emerged flies from 'emergence containers' to release devices.

Deliverable 6: Egg quality control
The main aim was to evaluate existing egg hatchability tests and their usefulness for egg quality control in a decentralised production technology.

Deliverable 7: Decentralised eclosion facility
The eclosion facility represented the third and final stage in the decentralised sterile insect mass rearing process for Mediterranean fruit fly, which divided production into three basic areas: egg production, sterile male pupae production, and eclosion operations leading to the release of sterile adult males. The eclosion model used a series of interactive tables detailing equipment, biological and economic variables, including a conceptual design of the layout of the facility and a brief description of the work processes. This model was designed as a tool to assist SIT technicians in planning eclosion facilities.

Deliverable 8: New adult male packaging technology
Adult emergence and release systems have a significant impact on some fitness traits of C. capitata sterile male flies. A new emergence cage with a capacity for one million pupae was developed. This novel emergence cage had the advantages of reducing labour requirements and increasing fly quality compared to the Aphis Tower and PARC Box systems. This cage fulfilled the pursued objectives, both for aerial release and for the new ground release machine developed in deliverable 9.

Deliverable 9: Novel land 'air plume' release system
This aim was to develop improved land release methods for SIT Medfly in European production areas by developing improved ground-based release machines. A prototype Ground release machine (GRM) was built and tested.

Deliverables 10 and 18: Trapping to population conversion algorithms and Trapping to release number algorithms
The objectives were to estimate the local population of wild flies and, from this, to calculate the required release rate of sterile males to control them.

Deliverables 11 and 24: Egg shipping protocols and standard operating procedure for egg shipping
Laboratory experiments simulating the shipment conditions and several real shipment experiments completed in the past between some medfly producing facilities, revealed that the shipment of eggs was feasible.

Deliverable 13: New HT technology
The aim of this work was to identify optimal egg age, duration and temperature of heat-treatment. For the experiments, Vienna 7-Toliman strain of Ceratitis capitata was used. To identify the optimal heat treatment conditions, combinations of following egg parameters were tested: egg age - 3, 12, 24, 36 hours after oviposition, heat-treatment duration - 6, 12, 18, 24 hours heat-treated eggs and temperature of heat-treatment - 30, 34, 38 and 40 oC.

Deliverable 14: Risk assessment for non-target organisms
The project promoted a pest control technology that was not widely applied across the Mediterranean at the start of the project. CLEANFRUIT, therefore, examined the potential for any new risks that might be introduced to the region with the uptake of SIT, and how these relate to risks already tolerated with current technologies.

Deliverable 15: Male only facility design
Within this deliverable, the egg production facility was developed as the model providing key parameters of the facility. The male-only pupae producing facility is the second component of the decentralised production. Eggs delivered from egg producing facility are seeded on the diet. At the end of larval development, larvae are collected, and allow pupating. At the end of their development, pupae are marked with fluorescent dye, packed and irradiate with proper dose of gamma radiation. Irradiated pupae are subsequently distributed to eclosion facilities.

Deliverable 16: Growers awareness sessions
Lack of information and lack of communication between stakeholders have historically been key obstacles to the uptake of SIT in Europe and the Mediterranean. To address these issues, CLEANFRUIT developed and implemented an SIT dissemination strategy, a key element of which was a series of 12 seminars for the Mediterranean region to provide growers, local authorities, academics and other stakeholders with basic information about SIT.

Deliverable 17: Egg production facility - Design, production protocol, facility model
Within this deliverable, the egg production facility was developed as the model providing key parameters of the facility. The egg producing facility is the first component of the DP system. Eggs are produced in quantities sufficient to supply several pupae producing facilities. The model was designed to produce Medfly tsl strain recently used in almost all Medfly SIT programmes. Mass rearing of tsl requests using of filter rearing system to avoid of the occurrence of recombinants and possible break down of the whole production. The initial genetically pure rearing material originates from small colony, which is manually cleaned from any possible recombinant individuals. In following steps, this material is multiplied through colony streams (initiation and injection streams). At the end of this process, colony is big enough to establish last stream (release stream), producing eggs for shipping to pupae producing facility.

Deliverable 19: Cost benefit models for new SIT adopters
New adopters require a method for estimating the cost and value of SIT suppression programmes compared with current pesticide based practices for a range of geographic scales. Deliverable 19 was a novel spreadsheet model that provided an essential tool for assessing the costs and values of these options.

Deliverable 20: Financial tools to assist conversion to SIT
Activity in this area was focused on the production of a financing manual. The manual describes financing mechanisms that can be used by growers' organisations or national or regional authorities to implement an SIT programme. There was also a discussion of the costs which would be incurred during the establishment and operation of a programme. This was intended to provide a guide to the likely scale (though not the precise estimation) of the financial commitment which will be required.

Deliverable 21: Proposed changes to food safety and related standards
CLEANFRUIT created a food safety model to quantify the impacts on human health of different strategies to control Medfly in citrus. The deliverable also comprised a discussion of the key results of the model, which includes a comparison between chemical control and SIT. Another aspect was the evaluation of the benefits to human health from recent changes in European pesticide policy and the development of recommendations for policy improvements.

Deliverable 22: Cost model for release method
The objective of this deliverable was to provide a tool for comparing the costs of different release methods: one aerial release method and three ground based options.

Deliverable 23: Establishing harmonisation potential for SIT
This deliverable consists of an analysis of citrus production and pest control across the Mediterranean, addressing the question 'What would need to change to integrate the use of SIT into the current practices?' The national regulatory frameworks were also reviewed for compatibility with this technology.