Estimating SIT-driven population reduction in the Mediterranean fruit fly,Ceratitis capitata, from sterile mating

Abstract

Area-wide sterile insect technique (SIT) programs assume that offspring reduction of the target population correlates with the mating success of the sterile males released. However, there is a lack of monitoring tools to prove the success of these programs in real-time. Field-cage tests were conducted under the environmental conditions of the Mediterranean coast of Spain to estimate: (a) the mating success of sterile Vienna-8 (V8) Ceratitis capitata males using molecular markers and (b) their efficacy to reduce C. capitata populations under six release ratios of wild females to wild males to V8 males (1:0:0, 1:1:0, 1:1:1, 1:1:5, 1:1:10, and 1:1:20). Statistical models were developed to predict: (a) the number of females captured in traps, (b) sperm ID (sterile or not) in spermathecae of the trapped females, and (c) the viable offspring produced, using release ratio and temperature as predictors. The number of females captured was affected by relative humidity. However, its influence in the model was low. Female captures were significantly higher in ratios 1:0:0 compared to ratios where V8 males were released. The proportion of V8 sperm in spermathecae increased with temperature and with the number of V8 males released, but leveled off between ratios 1:1:10 and 1:1:20. In all seasons, except winter (no offspring), viable offspring increased with temperature and was lowest for ratio 1:1:20. For the first time, a strong negative relationship between proportion of V8 sperm detected by molecular tools and C. capitata offspring was established. The models obtained should contribute to enhance the efficacy of SIT programs against this pest.

Cryopreservation of Embryos of the Mediterranean Fruit Fly Ceratitis capitata Vienna 8 Genetic Sexing Strain

“…The PCR-RFLP test performed has been developed to differentiate among different medfly Vienna GSSs and also among different natural populations [ 45 , 46 ]. DNA was extracted from 10 individual flies per strain, using the DNeasy Blood and Tissue kit (Qiagen).…”

RNA Interference-Mediated Knockdown of Male Fertility Genes in the Queensland Fruit Fly Bactrocera tryoni (Diptera: Tephritidae)

“…The Sterile Insect Technique (SIT) has been used for the management of B. tryoni in Australia since the 1960s [ 2 ]. The technique is considered an ideal biological control method for pest insects, since it is species-specific and does not involve the dissemination of chemical pesticides into the environment [ 3 ]. It is based on the release of large numbers of sterile males that can effectively compete with wild males for mates, thereby reducing the number of viable offspring produced [ 4 ].…”

Toward Implementation of Mosquito Sterile Insect Technique: The Effect of Storage Conditions on Survival of MaleAedes aegyptiMosquitoes (Diptera: Culicidae) During Transport

“…There are a number of examples of SIT programs that have successfully eradicated their target pests. Three such examples are as follows: 1) the North and Central American screwworm fly ( Cochliomyia hominivorax Coquerel [Diptera: Calliphoridae]), which was eradicated from southern United States, Mexico, and all of Central America ( Atzeni et al 1994 , Krafsur and Lindquist 1996 , Wyss 2000 ); 2) the Mediterranean fruit fly ( Ceratitis capitata Wiedemann Wiedemann [Diptera: Tephritidae]), eradicated from Central America and Mexico ( Hendrichs et al 2002 , Juan-Blasco et al 2014 ); and 3) the tsetse fly ( Glossina austeni Newstead [Diptera: Glossinidae]), which was eradicated from the island of Zanzibar in Tanzania ( Vreysen et al 2000 , Dyck et al 2006 , Abd-Alla et al 2013 ).…”