荔枝蝽象卵寄生蜂——平腹小蜂体外培育研究

本文报道用人造寄主卵繁殖平腹小蜂Anastatus japonicus Ashmead^***成功的结果.筛选出最佳卵壳材料为32—36μm的聚丙烯膜,培养基为柞蚕蛹血淋巴44.4%、10%麦乳精33.3%、鸡蛋黄11.1%、尼氏盐11.1%.体外连代培养平腹小蜂的结果表明,除蛹化率(72—83%)外,各代间在寄生率(40—44%)、孵化率(94—96%)、羽化率(91—96%)、展翅率(97—99%)方面无明显的差别,且人造卵育出的各代蜂在身体大小、寿命及繁殖力方面均与柞蚕卵育出蜂基本相似或优于柞蚕卵育出蜂.筛选出的人工培养基的氨基酸种类与蓖麻蚕卵和柞蚕卵相同,但量上差异比较明显.本文还报道了平腹小蜂在人造寄主卵上的产卵过程.     

人工补充寄主卵对松林内卵蜂种群消长的影响

在不同生境的松林中,人工补充寄主卵都能提高寄生效果。但林地生境不同,寄生率有明显差异。在松阔混交林中补充寄主,其寄生率比对照提高5.5—16.2倍。植被稀疏的纯松林效果较差,补充的寄生率比对照提高3.0倍。 卵蜂种群消长随季节温度而变化,全年以5月中旬至6月下旬和9月中旬至10月中旬为两个寄生高峰。卵蜂种群与松毛虫种群的消长存在较明显的相依关系,卵蜂种群随着松毛虫种群的消长而消长。施药对卵蜂种群有较大影响,施药区比对照区的寄生率约降低一倍。在混交林中填充寄主卵,能促进卵蜂种群世代延续。在逐步改善林地生境的基础上,利用人工补充寄主,可以代替人工繁蜂放蜂。     

Intrinsic competition between two European egg parasitoids of the brown marmorated stink bug

Following the accidental introduction and spread of the invasive polyphagous agricultural pest Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), the two European egg parasitoids Anastatus bifasciatus (Geoffroy) (Hymenoptera: Eupelmidae) and Ooencyrtus telenomicida (Vassiliev) (Hymenoptera: Encyrtidae) have been investigated for inundative biological control. Since the competititve outcome between the two generalist parasitoids is difficult to predict, intrinsic competition was investigated with a time-course development study. Both species readily oviposited in H. halys eggs containing eggs and early instar larvae of the competitor, but oviposition decreased when eggs contained late instar larvae and pupae. Ooencyrtus telenomicida offspring emergence from multiparasitized eggs was significantly lower than that from rearing controls, independent of the order of parasitization. Anastatus bifasciatus offspring emergence was not influenced by the presence of O. telenomicida when it parasitized as the first species, but emergence was decreased after oviposition in eggs containing O. telenomicida larvae and pupae. There was no indication that O. telenomicida can act as a facultative hyperparasitoid of A. bifasciatus. These results suggest that A. bifasciatus is the superior intrinsic competitor and no or minor negative implications for A. bifasciatus are expected if released in combination with O. telenomicida.     

平腹小蜂属四新种记述：（膜翅目：旋小蜂科）

本文记述平腹小蜂属Ａｎａｓｔａｔｕｓ ４新种,即石城平腹小蜂Ａ;Ｓｈｉｃｈｅｎｇｅｎｓｉｓ,ｓｐ．ｎｏｖ;德兴平腹小蜂;Ａ;ｄｅｘｉｎｇｅｎｓｉｓ,ｓｐ．ｎｏｖ;麻纹蝽平腹小蜂Ａ;Ｆｕｌｌｏｉ,ｓｐ．ｎｏｖ。及黄褐平腹小蜂Ａ;ｆｇｌａｖｉｐｅｓ,ｓｐ．ｎｏｖ。模式标本保存于东西农业大学植物保护系昆虫标杯室。     

学习经历在平腹小蜂寄主选择过程中的作用

研究了已经交配与未经交配的平腹小蜂在羽化后不同时间对中间寄主柞蚕卵信息记忆的持效性,比较了经学习训练与未经学习训练的平腹小蜂在不同时间对其自然寄主荔枝蝽卵和中间寄主柞蚕卵的选择性。结果表明：交配过的平腹小蜂在大量羽化后96h检验柞蚕卵的时间和数量都显著增多,而未经交配的平腹小蜂在此时搜索寄主的时间也显著延长,说明平腹小蜂在此时对柞蚕卵信息的记忆开始明显减弱。经学习训练的和未经学习训练的平腹小蜂在大量羽化后96h对荔枝蝽卵的第一选择数和刺卵数都明显提高,并且前者较后者在各个时段对荔枝蝽卵的第一选择数、检验卵数以及刺卵数都多,说明经学习训练的平腹小蜂对荔枝蝽卵的趋性较高,并且随着时间的延长受柞蚕卵信息的干扰逐渐减小,对荔枝蝽卵的学习效果不断增强。     

A molecular tool to identify Anastatus parasitoids of the brown marmorated stink bug

Globally, Anastatus species (Hymenoptera: Eupelmidae) are associated with the invasive agricultural pest Halyomorpha halys (Stål) (Hemiptera: Pentatomidae). In Europe, the polyphagous Anastatus bifasciatus (Geoffroy) is the most prevalent native egg parasitoid on H. halys eggs and is currently being tested as a candidate for augmentative biological control. Anastatus bifasciatus frequently displays behavior without oviposition, and induces additional host mortality through oviposition damage and host feeding that is not measured with offspring emergence. This exacerbates accurate assessment of parasitism and host impact, which is crucial for efficacy evaluation as well as for pre‐ and post‐release risk assessment. To address this, a general Anastatus primer set amplifying a 318‐bp fragment within the barcoding region of the cytochrome oxidase I (COI) gene was developed. When challenged with DNA of three Anastatus species —A. bifasciatus, Anastatus japonicus Ashmead, and Anastatus sp.—, five scelionid parasitoid species that might be encountered in the same host environments and 11 pentatomid host species, only Anastatus DNA was successfully amplified. When applied to eggs of the target host, H. halys, and an exemplary non‐target host, Dendrolimus pini L. (Lepidoptera: Lasiocampidae), subjected to host feeding, no Anastatus amplicons were produced. Eggs of the two host species containing A. bifasciatus parasitoid stages, from 1‐h‐old eggs to pupae, and emerged eggs yielded Anastatus fragments. Confirmation of parasitoid presence with dissections and subsequent PCRs with the developed primer pair resulted in 95% success for 1‐h‐old parasitoid eggs. For both host species, field‐exposed sentinel emerged eggs stored dry for 6 months, 100% of the specimens produced Anastatus amplicons. This DNA‐based screening method can be used in combination with conventional methods to better interpret host‐parasitoid and parasitoid‐parasitoid interactions. It will help address ecological questions related to an environmentally friendly approach for the control of H. halys in invaded areas.     

双条杉天牛的生物学特性

双条杉天牛Semanotus bifasciatus(Motschulsky)是危害我国重要绿化树种侧柏的重要害虫。通过室内饲养观察及野外调查相结合的方法,观察分析双条杉天牛的各虫态历期、生活习性和发生规律,并得到出蜇率与温湿度的相关性,及在不同的温度条件下,该虫对颜色有不同的趋性,但总体而言,对绿色有较强的趋性,对无害防治具参考价值。     

THE NATURAL CONTROL EFFECT OF EGG PARA-SITOIDS ON LITCHI STINK BUG TESSARATOMA PAPILLOSA (HETEROPTERA: PENTATOMIDAE) IN LITCHI ORCHARD

Abstract  The distribution of eggs of the litchi stink bug Tessaratoma papillosa Drury was observed. By marking the eggs of T. papillosa in an integrated pest managed litchi orchard and in an orchard with chemical control, respectively, the control effect of the egg parasitoids on T. papillosa in the two kinds of licthi orchards was investigated in Guangzhou in 1996. The female T. papillosa began to oviposit in mid-March and laid eggs vigorously from early April to early June, and then successively entered the declining stage of oviposition in 1996 in Guangzhou. 86% of the litchi stink bug eggs were laid in the peak period of oviposion. Two egg parasitoids, Anastatus japonicus and Ooencyrtus phongi , were obtained in the integrated managed litchi orchard. The rate of eggs parasitized by A. japonicus and O. phongi attained to 3.2% -18.4% and 3.2%-30.4%, respectively. The united attack of the two parasitoid wasps destroyed 30.6% - 47% host eggs in the middle and late stages of T. papillosa oviposition. Only A. japonicus was collected in the chemical controlled litchi orchard and the percentage of eggs parasitized by this wasp was only 0.2% -2.8%.