Ceratitis capitata (Wiedemann) is one of the major pests currently affecting world fruit production. In Argentina’s northern Citrus-producing regions, C. capitata is actively multiplying in large exotic host fruits, ...Ceratitis capitata (Wiedemann) is one of the major pests currently affecting world fruit production. In Argentina’s northern Citrus-producing regions, C. capitata is actively multiplying in large exotic host fruits, such as Citrus paradisi Macfadyen (grapefruit), Citrus aurantium L. (sour orange) and Citrus sinensis L. (Osbeck) (sweet orange). Faced with this situation, the use of parasitoids as biocontrol agents is currently receiving renewed attention as a new biological tool for controlling pestiferous fruit flies within the Argentinean National Fruit Fly Control and Eradication Program (ProCEM). Consequently, a viable approach to controlling C. capitata involves the use of exotic parasitoids such as Diachasmimorpha tryoni (Cameron). In this study, the effectiveness of D. tryoni females to find and successfully parasitize C. capitata larvae infesting all Citrus species mentioned earlier was assessed. Parasitoids were allowed to forage for 8 h on grapefruits and oranges artificially infested with laboratory-reared C. capitata larvae under natural environmental conditions (field cage). Parasitoid emergence, parasitism, overall effectiveness, and sex ratio of parasitoid offspring were estimated as response variables. The higher effectiveness of D. tryoni females recorded from C. sinensis would be mainly a result of both increased host density per unit of fruit surface area and fruit physical features. The study provides evidence that D. tryoni contributed to C. capitata mortality in all Citrus species assessed. However, the mortality values recorded from C. sinensis, C. aurantium, and C. paradisi did not exceed 10%, 1.5%, and 1.7%, respectively. Nonetheless, D. tryoni might be selected to forage under both high and low host density conditions.展开更多
The Mediterranean fruit fly (Medfly), Ceratitis capitata (Wiedemann) is one of the major pests of fruit crops in Argentina and it is a phytosanitary barrier to the export of fresh fruits. In the Province of San Juan, ...The Mediterranean fruit fly (Medfly), Ceratitis capitata (Wiedemann) is one of the major pests of fruit crops in Argentina and it is a phytosanitary barrier to the export of fresh fruits. In the Province of San Juan, located in the central-eastern region of Argentina known as Cuyo, control strategies against Medfly in fruit-producing irrigated-valleys have been implemented by the National Fruit Fly Control and Eradication Program (ProCEM) jointly with the provincial government and the producers. This program uses an area-wide integrated pest management approach that includes the use of environment-friendly strategies to suppress or eradicate Medfly, such as the use of the sterile insect technique and the application of new-generation bait sprays, and more recently the release of the Indo-Pacific parasitoid Diachasmimorpha longicaudata (Ashmead). This exotic larval-prepupal endoparasitoid is being mass-reared on larvae of Vienna 8 TSL C. capitata strain at the BioPlanta San Juan facility. In this respect, the objective of this study was to assess the effectiveness of laboratory-reared D. longicaudata females in order to find and successfully parasitize Medfly larvae in different host fruit species once released under semi-arid environmental conditions in ecologically isolated fruit-growing valleys of San Juan. Ground releases were used to disperse parasitoids in 6 fruit-producing valleys. In total, 40,000 adult parasitoids were released at places with various Medfly host plants bearing fruits and in which no insecticides were regularly applied, such as backyards and small orchards. 119 D. longicaudata adults were recovered from 6 Medfly-infested fruit species that were collected in 5 release sites (Pocito, Zonda, Santa Lucía, Caucete, and Rivadavia). The highest number of parasitoids was recovered from fig, followed by grape, rose, orange, tangerine, and persimmon. Data provided from this study open up the possibility of implementing a parasitoid mass-release program in San Juan.展开更多
文摘Ceratitis capitata (Wiedemann) is one of the major pests currently affecting world fruit production. In Argentina’s northern Citrus-producing regions, C. capitata is actively multiplying in large exotic host fruits, such as Citrus paradisi Macfadyen (grapefruit), Citrus aurantium L. (sour orange) and Citrus sinensis L. (Osbeck) (sweet orange). Faced with this situation, the use of parasitoids as biocontrol agents is currently receiving renewed attention as a new biological tool for controlling pestiferous fruit flies within the Argentinean National Fruit Fly Control and Eradication Program (ProCEM). Consequently, a viable approach to controlling C. capitata involves the use of exotic parasitoids such as Diachasmimorpha tryoni (Cameron). In this study, the effectiveness of D. tryoni females to find and successfully parasitize C. capitata larvae infesting all Citrus species mentioned earlier was assessed. Parasitoids were allowed to forage for 8 h on grapefruits and oranges artificially infested with laboratory-reared C. capitata larvae under natural environmental conditions (field cage). Parasitoid emergence, parasitism, overall effectiveness, and sex ratio of parasitoid offspring were estimated as response variables. The higher effectiveness of D. tryoni females recorded from C. sinensis would be mainly a result of both increased host density per unit of fruit surface area and fruit physical features. The study provides evidence that D. tryoni contributed to C. capitata mortality in all Citrus species assessed. However, the mortality values recorded from C. sinensis, C. aurantium, and C. paradisi did not exceed 10%, 1.5%, and 1.7%, respectively. Nonetheless, D. tryoni might be selected to forage under both high and low host density conditions.
文摘The Mediterranean fruit fly (Medfly), Ceratitis capitata (Wiedemann) is one of the major pests of fruit crops in Argentina and it is a phytosanitary barrier to the export of fresh fruits. In the Province of San Juan, located in the central-eastern region of Argentina known as Cuyo, control strategies against Medfly in fruit-producing irrigated-valleys have been implemented by the National Fruit Fly Control and Eradication Program (ProCEM) jointly with the provincial government and the producers. This program uses an area-wide integrated pest management approach that includes the use of environment-friendly strategies to suppress or eradicate Medfly, such as the use of the sterile insect technique and the application of new-generation bait sprays, and more recently the release of the Indo-Pacific parasitoid Diachasmimorpha longicaudata (Ashmead). This exotic larval-prepupal endoparasitoid is being mass-reared on larvae of Vienna 8 TSL C. capitata strain at the BioPlanta San Juan facility. In this respect, the objective of this study was to assess the effectiveness of laboratory-reared D. longicaudata females in order to find and successfully parasitize Medfly larvae in different host fruit species once released under semi-arid environmental conditions in ecologically isolated fruit-growing valleys of San Juan. Ground releases were used to disperse parasitoids in 6 fruit-producing valleys. In total, 40,000 adult parasitoids were released at places with various Medfly host plants bearing fruits and in which no insecticides were regularly applied, such as backyards and small orchards. 119 D. longicaudata adults were recovered from 6 Medfly-infested fruit species that were collected in 5 release sites (Pocito, Zonda, Santa Lucía, Caucete, and Rivadavia). The highest number of parasitoids was recovered from fig, followed by grape, rose, orange, tangerine, and persimmon. Data provided from this study open up the possibility of implementing a parasitoid mass-release program in San Juan.
