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
Seminal gifts range from important material donations to items that provide little direct benefit to females.Promiscuous,female silk corn flies Euxesta eluta expel and consume male ejaculates immediately after mating....Seminal gifts range from important material donations to items that provide little direct benefit to females.Promiscuous,female silk corn flies Euxesta eluta expel and consume male ejaculates immediately after mating.The evolution and function of this peculiar behavior are currently unknown.We performed a series of experiments aimed to:determine if females under different dietary regimes derive nutrients or water for survival and/or reproduction from ejaculate consumption,if males suffer a fitness cost from supplying females with ejaculates,and if females prefer to mate and/or are more likely to store sperm from well fed than nutritionally stressed presumably inferior males.Experiments revealed that protein deprived E.eluta females derive nutrients for ovarian development through consumption of ejaculates of protein fed males.No seminal products affecting survival appear to be transferred in the consumed ejaculate.However,ovarian development,in contrast to testes growth,occurs in detriment of longevity.Females preferred to mate with protein fed males,yet sperm retention in spermathecae was extremely rare after a single mating.This finding suggests that females could be exerting post copulatory control.A key question that remained to be addressed for the understanding of this puzzling and promiscuous mating system is what ecological factors or male traits drive females to retain sperm from one or several males in order to achieve and/or maximize fertilization potential.展开更多
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.
基金This experiments where funded with PICT 2015 N°0191 awarded to SA.
文摘Seminal gifts range from important material donations to items that provide little direct benefit to females.Promiscuous,female silk corn flies Euxesta eluta expel and consume male ejaculates immediately after mating.The evolution and function of this peculiar behavior are currently unknown.We performed a series of experiments aimed to:determine if females under different dietary regimes derive nutrients or water for survival and/or reproduction from ejaculate consumption,if males suffer a fitness cost from supplying females with ejaculates,and if females prefer to mate and/or are more likely to store sperm from well fed than nutritionally stressed presumably inferior males.Experiments revealed that protein deprived E.eluta females derive nutrients for ovarian development through consumption of ejaculates of protein fed males.No seminal products affecting survival appear to be transferred in the consumed ejaculate.However,ovarian development,in contrast to testes growth,occurs in detriment of longevity.Females preferred to mate with protein fed males,yet sperm retention in spermathecae was extremely rare after a single mating.This finding suggests that females could be exerting post copulatory control.A key question that remained to be addressed for the understanding of this puzzling and promiscuous mating system is what ecological factors or male traits drive females to retain sperm from one or several males in order to achieve and/or maximize fertilization potential.
