title: Gamma Irradiation as a Phytosanitary Treatment of Bactrocera tau (Diptera: Tephritidae) in Pumpkin Fruits.
abstract: The fruit fly Bactrocera tau (Walker) is an important quarantine pest that damages fruits and vegetables throughout Asian regions. Host commodities shipped from infested areas should undergo phytosanitary measures to reduce the risk of shipping viable flies. The dose-response tests with 1-d-old eggs and 3-, 5-, 7-, 8-d-old larvae were initiated to determine the most resistant stages in fruits, and the minimum dose for 99.9968% prevention of adult eclosion at 95% confidence level was validated in the confirmatory tests. The results showed that 1) the pupariation rate was not affected by gamma radiation except for eggs and first instars, while the percent of eclosion was reduced significantly in all instars at all radiation dose; 2) the tolerance to radiation increased with increasing age and developmental stage; 3) the estimated dose to 99.9968% preventing adult eclosion from late third instars was 70.9 Gy (95% CL: 65.6-78.2, probit model) and 71.8 Gy (95% CL: 63.0-87.3, logit model); and iv) in total, 107,135 late third instars cage infested in pumpkin fruits were irradiated at the target dose of 70 Gy (62.5-85.0, Gy measured), which resulted in no adult emergence in the two confirmatory tests. Therefore, a minimum dose of 85 and 72 Gy, which could prevent adult emergence at the efficacy of 99.9972 and 99.9938% at the 95% confidence level, respectively, can be recommended as a minimum dose for phytosanitary treatment of B. tau in any host fruits and vegetables under ambient atmospheres.
authors.affiliation: Chinese Academy of Inspection and Quarantine, Beijing 100029, P.R. China.
authors.forename: Zhan
authors.initials: Z
authors.lastname: Guoping
authors.affiliation: Chinese Academy of Inspection and Quarantine, Beijing 100029, P.R. China.
authors.forename: Ren
authors.initials: R
authors.lastname: Lili
authors.affiliation: Chinese Academy of Inspection and Quarantine, Beijing 100029, P.R. China.
authors.forename: Shao
authors.initials: S
authors.lastname: Ying
authors.affiliation: Chinese Academy of Inspection and Quarantine, Beijing 100029, P.R. China.
authors.forename: Wang
authors.initials: W
authors.lastname: Qiaoling
authors.affiliation: Chinese Academy of Inspection and Quarantine, Beijing 100029, P.R. China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Daojian
authors.affiliation: Chinese Academy of Inspection and Quarantine, Beijing 100029, P.R. China. wangyuejin@263.net.cn.
authors.forename: Wang
authors.initials: W
authors.lastname: Yuejin
authors.affiliation: Chinese Academy of Inspection and Quarantine, Beijing 100029, P.R. China.
authors.forename: Li
authors.initials: L
authors.lastname: Tianxiu
mesh_terms: D000818:Animals; D028464:Cucurbita; D016266:Food Parasitology; D005720:Gamma Rays; D007814:Larva / Q000528:radiation effects; D010063:Ovum / Q000528:radiation effects; D011679:Pupa / Q000528:radiation effects; D033621:Tephritidae / Q000254:growth & development / Q000528:radiation effects*
keywords: Bactrocera tau; gamma radiation; irradiation; phytosanitary irradiation; pumpkin