The effects of insect-resistant transgenic cotton on the diversity of arthropod communities in cotton fields in North China were investigated during 2000-2001. The field experiments were conducted in non-insecticide treated plots of transgenic cotton lines (SGK321, a transgenic cotton variety carrying Cry1A+CpTI genes; GK12, a transgenic cotton variety carrying the Cry1Ac gene) and their conventional parent varieties (Shiyuan 321 and Shimian 3, respectively), and in sprayed plots of the parent varieties where pyrethroid insecticides were used regularly against the cotton bollworm. All the arthropods were sucked up using a portable suction device and identified to species wherever possible. They were later sorted into guilds (pests, natural enemies and neutral arthropods) for diversity analysis using the method of Shannon's index. The diversity of arthropod communities in transgenic cotton plots was similar to that in conventional cotton fields without spraying, but Shannon's index for total arthropod community and the neutral arthropod guild in Bt cotton fields were significantly higher than those in sprayed plots in the mid and late growing stages of cotton. It is concluded that planting of Bt cotton could increase the stability of arthropod communities in cotton ecological systems and benefit the management of insect pests in cotton.

Leafminers are the most important insect pests of vegetables in Hangzhou area, Zhejiang province, Southeast China as well as in the rest of China, but have never been investigated for species composition, relative abundance and their associated parasitoids. A survey was conducted in four localities of Hangzhou area during 1998-2000 to determine the distribution of leafminers and their parasitoids on vegetable crops and weeds in the field. Over 20,000 leafminers were collected and reared. The leafminer species found were Liriomyza sativae, L. chinensis and Chromatomyia horticola, with C. horticola and L. sativae the most abundant in spring and autumn, respectively. About 11,000 parasitoid adults were reared from the leafminers collected. In total 14 hymenopteran species of four families (one braconid, 10 eulophids, one megaspilid and one pteromalid) were found. Eleven species were reared from C. horticola, nine from L. sativae and seven from L. chinensis. Opius caricivorae and Chrysocharis pentheus were the dominant species. Seven species were recorded from L. chinensis for the first time. Eleven parasitoid species were reared from leafminers on two weeds (Veronica undulata and Sonchus oleraceus). Parasitoids caused 48.5-68.8% parasitism on leafminers on crops and 83.7% parasitism on leafminers on weeds in the later growing season of vegetable crops. The results suggest that leafminer populations are regulated to a certain extent by their natural enemies in the field.

黄腹潜蝇茧蜂Opius caricivorae Fischer是美洲斑潜蝇Liriomyza sativae Blandchard幼虫2蛹期的一种重要内寄生蜂。在实验室条件下，用菜豆Phaseolus vulgaris L上的美洲斑潜蝇作为寄主，对其成蜂的生物学特性做了初步研究。成虫主要在白天羽化，羽化高峰期在8:00～10:00，且多数（91%）当日交尾，羽化出的成蜂性比明显偏雌性（雌:雄=1151:1）。在17℃～33℃温度下，提供蜂蜜液时，黄腹潜蝇茧蜂雌蜂和雄峰的寿命随着温度的升高而缩短，雌蜂的寿命明显长于雄峰的寿命，分别从17℃时81天和47天降到33℃时的14天和13天。雌蜂羽化后1～2天即可产卵，在21℃～29℃温度下，产卵高峰期在2～7日龄，平均产卵量随温度变化的方程为y=-01057x2+21728x-201601（r2=01934）。而且成蜂取食能够致死寄主。另外，本文对雌蜂的寄主搜索、产卵和寄主取食行为做了详细描述。

对菜蛾盘绒茧蜂Cotesia plutellae多分DNA病毒的特性及其对寄主小菜蛾Plutella xylostella幼虫的生理效应进行了研究。结果表明：菜蛾盘绒茧蜂雌蜂输卵管萼中含有大量的多分DNA毒(polydnavirus，PDV)；一个PDV内含多个核衣壳，最多可达16个；核衣壳长40～168nm，直径39～40nm；PDV仅在输卵管萼细胞内复制；雌蜂产卵时，随蜂卵将PDV注入寄主血腔，并扩散到寄主的许多组织中；PDV可能先通过脱膜再侵染寄主组织。雌蜂经Co60辐射处理后再寄生（即假寄生）小菜蛾2龄、3龄和4龄初期的幼虫，被寄生后的寄主幼虫几乎全部不能化蛹，但末龄（即4龄）幼虫期显著延长，并在寄生后期，幼虫胸部有褐色的短翅芽出现；即将化蛹的4龄末小菜蛾幼虫被假寄生后，即使每头寄主被过寄生9次，依然能正常化蛹，但不能羽化。假寄生与正常寄生后寄主的脂肪体数量和形态结构有明显的不同，推测在正常寄生的情况下蜂卵孵化时释放的畸形细胞及随后的幼蜂可能对脂肪体的结构产生了作用。

首次利用同源28S rRNA D2基因序列对内茧蜂亚科Rogadinae（昆虫纲Insecta:膜翅目Hymenoptera；茧蜂科Braconidae）进行了分子系统学研究。本研究从95%～100%乙醇浸渍保存的标本中提取基因组DNA并扩增了10种内群种类和5种外群种类的28S rDNA D2片段并测序（GenBank序列号AY167645-AY167659），利用BLAST搜索相关的同源序列，采用了GenBank中13个种类的28S rRNA D2同源序列，然后据此进行分子分析。利用3个外群（共8个种类）和3种建树方法（距离邻近法distance-based neighbor-joining，NJ；最大俭约法maximum parsimony，MP；和最大似然法maximum likelihood，ML）分析了内茧蜂亚科内的分子系统发育关系。结果表明，由分子数据产生的不同的分子系统树均显示内茧蜂亚科是一个单系群。内茧蜂亚科内依据形态和生物学特征的分群（族和亚族）及其系统发育关系得到部分支持。NJ、MP和ML分析结果均表明内茧蜂族Rogadini不是一个单系，而是一个并系，其余3族则得到不同程度的支持。内茧蜂族可分成2个分支；“脊茧蜂属Aleiodes+弓脉茧蜂属Arcaleiodes”和“沟内茧蜂属Canalirogas+锥齿茧蜂属Conspinaria+刺茧蜂属Spinaria+内茧蜂属Rogas”，二者不是姐妹群。脊茧蜂属Aleiodes和弓脉茧蜂属Arcaleiodes始终是姐妹群。脊茧蜂属Aleiodes是一个单系，并可分成2个姐妹分支，这与依据形态和生物学特征的亚属分群相一致。弓脉茧蜂属Arcaleiodes Chen et He，1991是一个独立的属。分支“沟内茧蜂属Canalirogas+锥齿茧蜂属Conspinaria+刺茧蜂属Spinaria+内茧蜂属Rogas”的单系性仅得到部分分子数据的支持；因形态特异（腹部成甲壳状）而列为亚族级的刺茧蜂属Spinaria，分子分析没有证实这一点。横纹茧蜂族Clinocentrini是个单系，并在内茧蜂亚科的系统发育中处于基部（原始）的位置。我们研究结果还表明，阔跗茧蜂属Yelicones和潜蛾茧蜂属Stiropius相对应的阔跗茧蜂族Yeliconini和潜蛾茧蜂族Stiropiini 为2个独立的分支，与形态和生物学的结果一致，但它们在内茧蜂亚科的系统发育的位置不明，有待今后进一步研究。