橘小实蝇对不同品种苹果的选择偏好及适应性

Selection Preference and Adaptability of Bactrocera dorsalis to Different Varieties of Malus pumila

【目的】探究橘小实蝇(Bactrocera dorsalis)在6个主栽苹果品种果实上的选择偏好,了解不同品种苹果果实对橘小实蝇生长发育的影响。【方法】以3种早熟品种(华硕、红露、嘎拉)和3种晚熟品种(短枝富士、烟富三号、秦脆)为试验材料,使用硬度计和糖度折光仪测定苹果果实的硬度和糖度;设置完整果实、去皮果实和果实气味3种处理方式,将同成熟批次的同一处理方式果实放入养虫笼内,测定橘小实蝇对不同品种果实的访问数和产卵数;饲喂初孵幼虫不同品种果实,测定其取食后幼虫历期、化蛹率、蛹重等生长发育参数,分析其对不同品种苹果的选择偏好和生长发育适应性。【结果】橘小实蝇在不同品种苹果果实上的访问数和产卵数存在差异,雌虫对果实的不同品种和处理更为敏感。早熟品种的完整果实中,橘小实蝇更偏好选择嘎拉,该品种上的雌虫访问数和诱卵数分别达9.0头和105.0粒/果;晚熟品种的完整果实中,橘小实蝇更偏好选择秦脆,该品种上的雌虫访问数和诱卵数分别达5.5头和64.2粒/果。果实处理方式影响橘小实蝇的选择偏好,除嘎拉外,同一品种果实的不同处理方式中去皮果实上的访问数和产卵数更高;早熟品种中以华硕的去皮果实上诱卵数最高,达201.6粒/果,晚熟品种中以烟富三号的果实气味诱卵数最高,达83.8粒/装置;双因素方差分析发现,品种和果实处理方式会对访问数和诱卵数产生影响。橘小实蝇取食嘎拉后的幼虫历期最短,为11.9 d,蛹期以华硕最短,为9.9 d;化蛹率和羽化率在晚熟品种中更高,橘小实蝇幼虫取食不同品种苹果后的特定年龄-阶段存活率差异主要在2龄阶段,取食华硕和嘎拉的2龄幼虫发育速度最快,3 d时达到特定年龄-阶段存活率峰值。【结论】橘小实蝇对苹果不同品种的选择偏好存在差异,早熟品种中偏好选择嘎拉,晚熟品种中偏好秦脆;果实完整程度和气味对其选择偏好有影响,去皮果实和果实气味上的访问数和诱卵数普遍高于完整果实;橘小实蝇能在苹果果实上完成幼虫期的生长发育,具有在苹果园中繁殖危害的能力,橘小实蝇对苹果果实的选择偏好与后代的生长发育适合度关联性不强,同“选择性与适合度”假说存在差异。苹果园橘小实蝇综合管理中应当加强对嘎拉和秦脆品种的受害情况监测,农事操作中避免损伤果实并及时摘除受损果实。

【Objective】This study aims to investigate the preference of Bactrocera dorsalis for fruits of six main Malus pumila varieties and to understand the effects of different varieties of M.pumila on the growth and development of B.dorsalis.【Method】Three early maturing varieties(Huashuo,Honglu,Gala)and three late maturing varieties(Duanzhifushi,Yanfu No.3,Qincui)were used as test materials.The hardness and sugar content of M.pumila fruit were determined by hardness tester and a brix refractometer.Three types of fruit handling methods were employed:whole fruit,peeled fruit and fruit odor.Fruits of the same ripening batch of the same handling method were placed in rearing cages,to measure the numbers of visits and laid eggs by B.dorsalis on fruits of different varieties were determined.Feeding different varieties of fruits to the first hatching larvae,the growth and development parameters of larval duration,pupation rate,pupal weight and other parameters after feeding were determined.The selection preference and development adaptability of B.dorsalis to different varieties of M.pumila were analyzed.【Result】There were differences in the numbers of visits and laid eggs of B.dorsalis on different varieties of fruits.The female adults were more sensitive to different varieties and fruit handling methods.B.dorsalis preferred to choose Gala among whole fruits of the early maturing varieties,which had 9.0 female visits and 105.0 eggs per fruit,respectively.While among the late maturing varieties,B.dorsalis showed a stronger preference for Qincui,and the numbers of female visits and laid eggs on this variety reached to 5.5 and 64.2 eggs per fruit,respectively.The fruit handling methods influenced the selection preference of B.dorsalis.With the exception of Gala,the numbers of visits and laid eggs on peeled fruits were higher in different fruit handling methods of the same variety.Among the early maturing varieties,Huashuo had held the highest number of laid eggs on the peeled fruit,reached to 201.6 eggs per fruit,and among the late maturing varieties,Yanfu No.3 had held the highest number of laid eggs on fruit odor,reached to 83.8 eggs per device.Two-way ANOVA found that variety and fruit handling method had an impact on the number of visits and laying eggs.Larvae of B.dorsalis had held the shortest period of 11.9 d in Gala and the shortest pupal stage in Huashuo of 9.9 d after feeding on different fruits.Pupation and emergence rates were higher in late maturing varieties.The difference in the age-stage-specific survival rate of the larvae that fed on different varieties was mainly in the 2nd instar stage,and the 2nd instar larvae which fed on Huashuo and Gala had held fastest development rate and peaked at the 3rd day.【Conclusion】There were differences in the selection preference of B.dorsalis on different M.pumila varieties.Gala was preferred in early maturing varieties,while Qincui was preferred in late maturing varieties.Fruit integrity and fruit odor had an effect on the selection preference.The numbers of visits and laid eggs on peeled fruit and fruit odor were generally higher than those on whole fruit.B.dorsalis can finish the growth and development of larvae on M.pumila fruit,and it has the ability to reproduce damage in apple orchards.The correlation between the preference of B.dorsalis for M.pumila fruit and the fitness of offspring’s growth and development is not strong,which is different from the hypothesis of“selectivity and fitness”.In the comprehensive management of B.dorsalis in apple orchards,the damage monitoring of Gala and Qincui varieties should be strengthened,and the damaged fruits should be avoided and removed in time in agricultural operations.