寄生美国白蛾的啮小蜂一新种(膜翅目,姬小蜂科)

记述了从美国白蛾蛹中养出的姬小蜂科啮小蜂亚科1新种,即白蛾短角啮小蜂Tetrastichus litoreus sp．nov．。本种群集内寄生于美国白蛾蛹中,以老熟幼虫在寄主蛹中越冬,成蜂的雌雄性比为5：1。新种的模式标本保存于中国林业科学研究院昆虫标本馆。     

低温冷藏对不同虫期啊氏啮小蜂存活率的影响

研究啊氏啮小蜂Tetrastichus hagenowii(Ratzeburg)不同发育阶段在10℃贮存不同天数对其存活率的影响。结果表明,啊氏啮小蜂卵期冷藏10d、20d,其发育历期分别较对照延长6.6d、9.4d,平均每粒卵荚出蜂量比对照分别少10头、9.8头,冷藏卵荚的出蜂率较对照无差异,卵期冷藏30~90d,卵荚出蜂率为0。啊氏啮小蜂幼虫期冷藏10~90d,其发育历期较对照延长1.8~26.3d,平均每粒卵荚出蜂量、卵荚孵化率较对照分别下降5.6~50.3头、8.4%~70.4%。啊氏啮小蜂蛹期冷藏10~90d,其发育历期较对照缩短3.4~17.5d,平均每粒卵荚出蜂量和卵荚孵化率均随冷藏天数增加而明显降低。     

枸杞木虱啮小蜂寄生行为及生物学特性的研究

枸杞木虱啮小蜂Tetrastichussp .是枸杞木虱ParatriozasinicaYang&Li若虫的外寄生蜂 ,自然寄生率可达 86 5 %。在温度为 2 0～ 2 5℃的室内条件下 ,完成 1个世代需 1 4～ 2 0d。成虫寿命与取食有关 ,取食 1 5 %的蜂蜜水 ,雌性成虫寿命为 1 2～ 1 7d,雄性成虫为 4～ 6d。成蜂最喜欢在 3龄和 4龄若虫上产卵。自然种群消长与寄主虫口密度相关。每年 7月到 8月下旬该蜂寄生率高 ,9月份下降 ,1 0月份几乎不见。     

Biological assessment of Tetrastichus brontispae,a pupal parasitoid of coconut leaf beetle Brontispa longissima

To control coconut leaf beetle, Brontispa longissima (Gestro), the pupal parasitoid Tetrastichus brontispae Ferrière was imported from Taiwan and its biology was studied in quarantine in Hainan, China. The parasitoid development includes an egg, three larval instars and three pupal stages. Its developmental time from egg to adult was 19.5±0.5 days under conditions of 24±2°C and 75±5% relative humidity (RH). Temperature had no effect on the sex ratio of offspring, but significantly affected the parasitism rate and reproduction. The parasitism rates were 98.07, 97.97 and 95.03% at 28, 24 and 20°C, respectively, whereas the parasitism rate was 52.18% at 18°C and 69.48% at 30°C, respectively. Furthermore, the parasitoids reared at 18 and 30°C produced fewer offspring than those at 20, 24 and 28°C, respectively. With the increase in temperature, developmental time decreased linearly from 46.19 days at 18°C to 17.10 days at 28°C. RH significantly influenced development, parasitism rate and the reproduction of T. brontispa. With the decrease of RH, developmental time increased from 22.94 days at 20% RH to 18.84 days at 95% RH. In contrast, parasitism rate and the number of offspring per female increased with the increase of RH. Though emergence rates between 50 and 95% RH were much higher than those between 20 and 35% RH, the sex ratios between 20 and 95% RH were not different. Photoperiod had no effect on parasitism, the number of offspring per female, emergence and the sex ratio of T. brontispae, but developmental time was significantly different for different photoperiods. Sucrose, honey and glucose significantly enhanced adult longevity, parasitism and the number of offspring per female of T. brontispae, but had no effect on the sex ratio and survival. Females of T. brontispae only parasitized fourth to fifth larval instars and 1–5-day-old pupae, but there was a significant difference in the number of offspring per female, development time, emergence and the sex ratio of offspring in different instars. These results showed that 1-day-old pupae, a temperature of 24–28°C and 65–95% RH were optimal for T. brontispae. These findings should be helpful in developing a production system to rear and release T. brontispae in large enough quantities to effectively control coconut leaf beetle.     

Larval parasitoids of Lilioceris lilii (Coleoptera:Chrysomelidae) in Sweden and potential for biological control

A survey of the parasitoid complex of lily leaf beetle (Lilioceris lilii) was conducted in Sweden from 2006 to 2007. Total parasitism varied between 21 and 57%. The most abundant parasitoids were the ichneumonids Lemophagus errabundus and L. pulcher and the eulophid Tetrastichus setifer. The potential for biological control is discussed.     

低温贮存对椰心叶甲啮小蜂品质的影响

研究低温贮存椰心叶甲蛹Brontispa longissima(Gestro)和椰心叶甲僵蛹对椰心叶甲啮小蜂Tetrastichus brontispae Ferriere种群品质的影响。寄生10℃低温贮存1~4日龄椰心叶甲蛹结果表明,1日龄椰心叶甲蛹的寄生率、羽化率、出蜂率、单蛹出蜂数、后代寄生能力均优于其他日龄,其次为2、3日龄的椰心叶甲蛹,最差为4日龄的椰心叶甲蛹。1日龄椰心叶甲蛹在10℃下贮存5,10,15,20d后,上述生物学指标和种群参数均随贮存天数增加而降低,其中以5d和10d的净生殖率、内禀增长率和周限增长率较未经低温贮存的差异小。1~11日龄椰心叶甲僵蛹于10℃贮存10d的结果表明,8日龄椰心叶甲僵蛹的雌蜂寿命、羽化率、单蛹出蜂数、寄生能力均优于其他日龄僵蛹。8日龄椰心叶甲僵蛹在10℃下贮存5,10,15,20d后,上述生物学指标和种群参数均随贮存天数增加而显著低于对照。     

啮小蜂毒液对寄主亚洲玉米螟蛹发育的影响

假寄生和毒液注射实验表明啮小蜂Tetrastichussp .毒液能永久麻痹亚洲玉米螟蛹Ostriniafurnacalis,较高剂量的毒液对亚洲玉米螟蛹有不同程度的麻痹作用。麻痹的蛹在室温下较长时间内不腐烂和干化。低剂量毒液能延长亚洲玉米螟蛹期 1～ 3d ,导致畸形成虫。啮小蜂初产卵转移寄主实验证实毒液可以帮助啮小蜂卵在亚洲玉米螟蛹体内的发育 ,啮小蜂初产卵在转移寄主体内发育到羽化时间为 2 5d ,比它们在原寄主内的羽化时间增加 8d左右 ,初产蜂卵与 1个毒液储液囊当量的毒液同时注入转移寄主体内 ,初产卵的羽化时间明显缩短 ,死亡率降低     

木虱啮小蜂对枸杞、枸杞木虱的行为反应

木虱啮小蜂Tetrastichus sp.是枸杞木虱Paratrioza sinica Yang & Li若虫外寄生蜂,是控制枸杞木虱种群数量动态的重要因子之一。为查明其寻找寄主的信息素,应用四臂嗅觉仪、培养皿两种方法测定了枸杞Lycium barbarum L.的健康叶、虫伤叶、枸杞木虱若虫、若虫与叶复合体、卵与叶复合体和若虫分泌物等不同物质对木虱啮小蜂行为反应的影响。结果证明枸杞木虱若虫分泌物对木虱啮小蜂有明显的吸引作用,四臂嗅觉仪测定时有73%的雌蜂趋向分泌物材料区（P=0.0000）。枸杞健康叶, 虫伤叶及其水、正丁烷提取物, 卵与枸杞叶复合体对木虱啮小蜂无明显吸引作用。木虱若虫水提物及正丁烷提取物在培养皿中可吸引木虱啮小蜂并可引起刺探行为,但嗅觉仪测定时单独若虫并不吸引木虱啮小蜂,只有活体若虫与枸杞叶片复合体才对木虱啮小蜂有吸引作用（P=0.0004）。木虱啮小蜂通过与寄主若虫的接触,可提高其搜索效率。接触过寄主若虫的雌蜂第一次找到寄主的时间显著少于未曾接触寄主若虫的雌蜂,前者只用后者1/4的时间,说明该寄生蜂能对其寄主若虫进行学习。     

RearingTetrastichus gallerucae [hymenoptera: Eulophidae] for biological control of the ELM leaf beetleXanthogaleruca luteola

Tetrastichus gallerucae (Fonscolombe) was collected in southern France in 1985 and is being reared at the Division of Biological Control in Albany, Ca for use against the elm leaf beetle (ELB),Xanthogaleruca luteola (Müller) in northern California. This egg parasitoid can be reared easily by keeping the beetle eggs on a moist substrate to prevent desiccation and by inhibiting the growth of mold with air currents. A laboratory colony of ELB adults provides a constant supply of fresh eggs for the parasitoids. In 1985 and 1986 over 80,000T. gallerucae were released at 17 sites.      

Patch-exploitation patterns in an egg parasite of elm leaf beetle

Eggs of elm beetle,Pyrrhalta luteola (Muller), normally occur in masses which can be viewed as discrete host patches in space and time. Analysis of>800 egg masses from 3 field sites in northern California revealed that the number of eggs/mass varied from 2 to>40 and that the imported egg parasiteTetrastichus gallerucae (Fonsc.) exploited a relatively large proported of the egg masses at certain times. The spatial relationship between parasitization and number of eggs/egg mass was assessed in 2 ways-i.e., for exploited masses only and for all masses combined (exploited+nonexploited). Percent parasitization was density independent in most cases for both data sets. It is suggested that both methods of analysis can provide patterns which are relevant to biological control of insect pests.