桃小食心虫蛹的辐照耐受性比较研究

A comparison study on the radiation tolerance of Carposina sasakii (Lepidoptera: Carposinidae) pupae

桃小食心虫（Carposina sasakii Matsmura）是一种严重危害仁果和核果的重要害虫,受到相关水果进口国广泛关注。辐照作为一种重要的替代溴甲烷熏蒸的检疫处理技术,正在扩大其商业化应用。本研究应用钴-60伽马射线在40、80、120、160、200和240 Gy辐照剂量下分别处理3、6、9日龄蛹,观察辐照对羽化、产卵和F1代卵孵化的影响。结果表明：40 Gy以上剂量显著降低3日龄蛹的羽化率,40~240 Gy辐照不明显影响9日龄蛹的羽化率;100%阻止3、6日龄蛹羽化后产卵（或卵孵化）的最小剂量分别为200（120）、240（160）Gy,而240 Gy不能100%阻止9日龄蛹的产卵及孵化;对辐照剂量与阻止F1代卵孵化数据进行机率值分析的结果显示,阻止6、9日龄蛹产生子代1龄幼虫的最低剂量（ED99.9968）分别为246.6（222.9~277.6）Gy和316.6（271.0~391.8）Gy。说明桃小食心虫蛹的耐受性随着蛹龄的增加而增强,发育完善的9日龄蛹的耐受性最强。为此,建议317 Gy作为水果感染桃小食心虫蛹检疫处理的最低吸收剂量。

The peach fruit moth Carposina sasakii Matsmura, a serious pest of many pome and stone fruits, is an important pest that is mostly concerned by importing countries. Ionizing irradiation is a kind of altemative to methyl bromide in place, it is increasing in commercially uses worldwide. In this investigation, dose-response tests were conducted on the 3-, 6-, and 9-d-old pupae at the dose of 40, 80, 120, 160, 200, and 240 Gy, respectively, to observe the adult emergence, egg laying and hatching. The percentage of adult emergence was not significant decreased for 9-d-old pupae comparing with their control, but it was significant decreased for 3-d-old pupae at all radiation doses. The minimum dose to 100% prevent laying egg （or egg hatching） from 3-, 6-, and 9-d-old pupae was 200 （120）, 240 （160）, and 〉240 Gy, respectively. Probit analysis was used to analyze the relationship between dose and mortality of F1 eggs, and the estimated mean doses to prevent egg hatching at the efficacy of 99.9968% were 246.6 （95%CI：222.9, 277.6） Gy for 6-d-old pupae, and 316.6 （95%CI： 271.0, 391.8） Gy for 9-d-old pupae, respectively. The tolerance to radiation in C. sasala＇i pupae was accordingly increased with the ages, and the well-developed 9-d-old pupae was determined to be the most tolerant stage. Therefore, a radiation dose of 317 Gy could be suggested for the phytosanitary treatment of any commodities contaminated with peach fruit moth pupae.