title: Parasitism, emergence, and development of Spalangia endius (Hymenoptera: Pteromalidae) in pupae of different ages of Bactrocera cucurbitae (Diptera: Tephritidae).
abstract: The wasp Spalangia endius Walker (Hymenoptera: Pteromalidae) is a major parasitoid of the pupae of fruit flies, which are a common agricultural pest. An understanding of this intricate host-parasitoid interaction could provide basic information necessary for the sustainable integrated biological control of fruit flies. In this study, we investigated the effect of S. endius on different-aged pupae of the melon fly Bactrocera cucurbitae Coquillett by using choice and nonchoice tests under laboratory conditions. We showed that S. endius females oviposited, and their progeny successfully developed, in different-aged pupae of B. cucurbitae regardless of the method of exposure. There was an oviposition preference for 3-5-d-old pupa. The highest mean percentage parasitism occurred on 4- and 5-d-old hosts, followed by 2- and 3-d-old hosts. The average development time for both males and females was significantly longer in 6-7-d-old hosts than in the younger host stages. Adult females that developed from younger host pupae (2-5-d old) were significantly heavier than those from older host pupae (6-7-d old), and they also lived longer. The sex ratio (proportion of females) of the parasite progeny decreased with an increase in host age. Host mortality also decreased gradually as the pupal age increased. The differences in development time, body weight, and longevity between females and males were significant. These results suggest that S. endius is a good candidate for the biological control of B. cucurbitae.
authors.affiliation: Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China lk0750@163.com.
authors.forename: Liang-De
authors.initials: LD
authors.lastname: Tang
authors.affiliation: Hainan Academy of Agricultural Sciences, Institute of Agreoenvironment and Plant Protection, Hainan Key Laboratory for Control of Plant Diseases and Insect Pests, Haikou 571100, China.
authors.forename: Xun-Cong
authors.initials: XC
authors.lastname: Ji
authors.affiliation: Engineering Research Center of Biological Control, Ministry of Education, College of Natural Resource and Environment, South China Agricultural University, Guangzhou 510642, China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Han
authors.affiliation: Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China.
authors.forename: Bu-Li
authors.initials: BL
authors.lastname: Fu
authors.affiliation: Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China lk0750@163.com.
authors.forename: Kui
authors.initials: K
authors.lastname: Liu
mesh_terms: D000367:Age Factors; D000818:Animals; D005260:Female; D008136:Longevity; D008297:Male; D010058:Oviposition / Q000502:physiology*; D010572:Pest Control, Biological / Q000379:methods; D011679:Pupa / Q000469:parasitology; D012744:Sex Ratio; D033621:Tephritidae / Q000469:parasitology*; D014863:Wasps / Q000196:embryology / Q000254:growth & development / Q000502:physiology*
keywords: biological control; host suitability; melon fly; parasitoid; pupal age