三化螟卵块寄生蜂-螟卵啮小蜂研究概况

螟卵啮小蜂Tetrastichus schoenobii Ferriere是一种寄生三化螟Trypoyyza incertulas(Walker)卵块的重要天敌.本文总结了其生物学、形态学、生态学以及应用研究等方面的研究概况,并对其开发利用提出新的思路.     

霍氏啮小蜂外生殖器及其感器的超微结构

霍氏啮小蜂Tetrastichus howardi(Olliff)是许多鳞翅目害虫的群居性蛹寄生蜂。为分析霍氏啮小蜂成虫产卵器和交配器上与成虫产卵和交配有关的感受器类型,本文利用扫描电镜对霍氏啮小蜂成虫产卵器和交配器的超微结构进行了观察。在霍氏啮小蜂成虫产卵器上共发现了7种感受器,分别是毛形感器1(TS1)、毛形感器2(TS2)、刺形感器2(CH2)、分泌毛孔(SP)、栓锥形感器1(SS1)、栉齿状感器(DS)、浅凹形感器(SD)和火山形感器(VS)。交配器上共发现6种感受器官,分别是栓锥形感器2(SS2)、火山形感器(VS)、表皮孔(CP)、鸡冠状结构(Crs)、钟形感器(CAS)和毛形感器3(TS3)。结果表明霍氏啮小蜂可通过产卵器和交配器上感受器获得与寄主和配偶相关的信息,进而调控产卵行为和交配行为。     

螟卵啮小蜂寄主——莎草螟

据广西农科院植保室和玉林地区农业试验站植保室报道,1973年在广西玉林地区发现在硕大莎草(Scirpus grossus)上有一种螟蛾(暂叫莎草螟),其卵是啮小峰的寄主。 硕大莎草是一种野生杂草,在该地分布很广,常年青绿,幼虫蛀食后不造成枯心。比用马蹄饲养白螟或用茭白饲养褐边螟的成本低,有利于大量繁殖啮小蜂。 莎草螟在莎草上的虫口密度很高,一般每株有虫     

霍氏啮小蜂的卵巢发育和卵子发生

霍氏啮小蜂是一些鳞翅目和双翅目昆虫蛹的寄生蜂。本文描述该寄生蜂从亚洲玉米螟羽化后0,6 12,18,24,30,36,42,48,54,60,66和72 h的卵巢发育和卵子发生过程。霍氏啮小蜂雌性生殖系统为典型的膜翅目姬小蜂类型,包括2个卵巢,每个卵巢通常有8-9根卵巢管,另有1对输卵管附腺,1个受精囊和1个受精囊腺等。卵黄和卵子形成于羽化后12 h,刚羽化的雌蜂不含成熟卵(成熟卵指数OI=0),成熟卵出现在羽化后24 h,成熟卵数量随后不断增加至数量较为稳定。卵巢管内卵数与雌蜂的体长和头宽呈正相关,相关系数分别为0.859和0.907。研究结果表明霍氏啮小蜂属卵育型(synovigeny)寄生蜂,本文还讨论了卵育型霍氏啮小蜂的卵成熟策略。     

螟卵啮小蜂的雄性外生殖器

<正> 螟卵啮小蜂Tetrastichus shoenobii Ferriere是三化螟卵的最重要的寄生蜂。其雄性外生殖器的构造、形态尚未见报道。 作者通过解剖、制片,在显微镜下观察,初步描述于下: 阳基长榄形,长与宽之比约为1:0.3[图(1)];阳基侧瓣形态特殊,端部具一刺突;钩爪构造奇异,略呈长方形而端部稍为膨大,具有一微弯的爪状突,整个钩爪由一细长的骨片与阳基侧瓣相连[图(2)]。阳茎匀称,端部呈弹头状,在阳茎开口处的两侧,各具3个圆     

椰心叶甲蛹寄生蜂——椰心叶甲啮小蜂的生物学特性

椰心叶甲啮小蜂Tetrastichus brontispae Ferrière是椰心叶甲Brontispa longissima（Gestro）蛹的重要内寄生蜂,2004年从台湾引入到海南。在实验室条件下,对椰心叶甲啮小蜂的形态、行为、发育、存活、繁殖等生物学特性进行了观察研究。结果表明,雌蜂个体比雄蜂大,腹部明显可见产卵器。每头寄主蛹出蜂量平均为21.5头,其中雌蜂约占77.4%。椰心叶甲啮小蜂羽化不久即能交配,交配时间约为1～2 min。椰心叶甲啮小蜂的产卵高峰期在交配后的24 h内,且产卵量受温度的影响较大; 蜂蜜、蔗糖、葡萄糖均能有效地延长其成虫的寿命,并能提高其怀卵量和寄生率,其中以取食蜂蜜的效果最好。该蜂发育、存活和繁殖的适宜温度为20℃～28℃,低于16℃或高于30℃对其存活不利。利用16℃、20℃、24℃、28℃、30℃下的发育历期和有效积温公式计算出椰心叶甲啮小蜂的发育起点温度（C）为9.6℃,有效积温（K）为324.9日·度。     

螟卵啮小蜂繁育利用技术的探讨

螟卵啮小蜂是防治水稻三化螟较为理想的一种卵寄生蜂。但由于寄主单纯,人工大量繁殖尚有一定困难,影响生产上大量应用。 1974年零陵地区科技办、江永县科技办曾组织有关单位联合对啮小蜂繁育利用技术进行了探索。1975年我所在1974年工作的基础上,又进行了试验。主要     

环境因素对螟卵啮小蜂繁殖力的影响

螟卵啮小蜂(Tetrastichus schoenobii Ferriere)是兼有寄生和扑食习性的螟卵寄生蜂,是防治水稻三化螟虫较有利用前途的天敌昆虫。1972—1974年,我们在湖北省进行了普查,并从海南岛引种大田投放,并在室内对其生物学特性进行了观察研究。现将几种主要环境因素对其繁殖力的影响报告于下。     

冷藏三化螟卵块繁殖螟卵啮小蜂试验

螟卵啮小峰(Tetrastichus schoenobii Ferriere)是控制三化螟为害的一种有效卵蜂,但在人工大量繁蜂实践中,往往遇到有蜂无寄主卵的矛盾,因此必须研究解决保存寄主卵的方法,才能保证顺利地按计划进行育蜂治螟。1974年我们进行了三化螟卵块低温保存的试验,取得初步效果。     

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.     

稻螟赤眼蜂对二化螟和台湾稻螟的控制潜能评价

为了明确稻螟赤眼蜂种群增长力与水稻螟虫种群增长力之间的关系和评价稻螟赤眼蜂的控害能力,通过生命表方法,组建了二化螟和台湾稻螟在水稻上的实
验种群生命表,以及稻螟赤眼蜂在二化螟卵和台湾稻螟卵上的生殖力表,测定了稻螟赤眼蜂对两种螟虫卵的寄生能力.结果表明：二化螟和台湾稻螟的世代历期（T）分别为56.40 d和47.80 d,内禀增长率（r_m）分别为0.0489和0.072.稻螟赤眼蜂在二化螟卵和台湾稻螟卵上的平均T分别为9.75 d和9.78 d,r_m分别为0.3161和0.3154.通过比较分析稻螟赤眼蜂与两种螟虫的实验种群生命表参数,可知稻螟赤眼蜂能够有效控制两种水稻螟虫,赤眼蜂种群增长力相对于螟虫种群是超前而不是跟随关系.     

Parasitism Behavior of Tetrastichus howardi (Hymenoptera: Eulophidae) on Larvae and Pupae of Sugarcane Borers

Journal of Insect Behavior - Control of the sugarcane borers, Diatraea saccharalis and Diatraea impersonatella (= D. flavipennella) (Lepidoptera: Crambidae), in Brazil, is based on mass release of...     

Biology of Tetrastichus howardi (Olliff) (Hymenoptera: Eulophidae): A facultative Hyperparasitoid of stem borers

The biology of the parasitoid Tetrastichus howardi, which was introduced from the Philippines into South Africa for the biological control of the stem borer Chilo partellus, was studied in the laboratory. On average, a T. howardi female produced 101 progeny (92% females) which developed in 4.3 hosts. The upper threshold temperature for development was around 33°C, the minimum threshold was calculated as 12.8°C and the thermal constant as 239.8 day‐degrees. With hosts, females lived 23.6 and males 16.7 days. T. howardi was found to be a facultative hyperparasitoid with a very wide host range. As a primary parasitoid, it developed in pupae of various Lepidoptera as well as Coleoptera and Hymenoptera and as a hyperparasitoid in dipteran and hymenopteran parasitoids. A linear relation was found between the number of emergent parasitoids and the volume of the host from which they emerged. Preference tests indicated that T. howardi preferred to parasitize the phytophagous insects C. partellus and Heliothis armigera, over their parasitoids Xanthopimpla stemmator and Palexorista laxa. The host selection of inexperienced T. howardi females was different from the experienced parasitoids. When given a choice, females showed preference for the host species they were allowed to parasitize previously and the host species from which they had been reared. The use of facultative hyperparasitoids in biological control in general and against stem borers in South Africa in particular is discussed.     

Role of volatiles emitted by host and non-host plants in the foraging behaviour of Dentichasmias busseolae, a pupal parasitoid of the spotted stemborer Chilo partellus

The role of volatiles from stemborer host and non‐host plants in the host‐finding process of Dentichasmias busseolae Heinrich (Hymenoptera: Ichneumonidae) a pupal parasitoid of Chilo partellus (Swinhoe) (Lepidoptera: Crambidae) was studied. The non‐host plant, molasses grass (Melinis minutiflora Beauv. (Poaceae)), is reported to produce some volatile compounds known to be attractive to some parasitoid species. The studies were conducted to explore the possibility of intercropping stemborer host plants with molasses grass in order to enhance the foraging activity of D. busseolae in such a diversified agro‐ecosystem. Olfactometric bioassays showed that volatiles from the host plants maize, Zea mays L., and sorghum, Sorghum bicolor (L.) (Poaceae), were attractive to the parasitoid. Infested host plants were the most attractive. Volatiles from molasses grass were repellent to the parasitoid. Further tests showed that volatiles from infested and uninfested host plants alone were preferred over those from infested and uninfested host plants combined with the non‐host plant, molasses grass. In dual choice tests, the parasitoid did not discriminate between volatiles from maize infested by either of the two herbivore species, C. partellus or Busseola fusca Fuller (Lepidoptera: Noctuidae). Volatiles from sorghum infested by C. partellus were preferred over those from C. partellus‐infested maize. The study showed that the pupal parasitoid D. busseolae uses plant volatiles during foraging, with those from the plant–herbivore complex being the most attractive. The fact that volatiles from molasses grass were deterrent to the parasitoid suggested that intercropping maize or sorghum with molasses grass was not likely to enhance the foraging behaviour of D. busseolae. Volatiles from the molasses grass may hinder D. busseolae's host location efficiency.     

Indirect interaction between butterfly species mediated by a shared pupal parasitoid

Indirect interactions among species can greatly affect their abundances and the structure of the community they live in. Using a field experiment, we tested the hypothesis that congeneric butterfly species interact indirectly through a shared pupal parasitoid. We predicted that symmetrical apparent competition would lead to high parasitism of both species, and the effect would increase with regional butterfly abundance. Instead, parasitism of one host, Melitaea cinxia, was reduced in the presence of the second host, M. athalia. Parasitism of M. athalia did not differ whether or not M. cinxia was present. This pattern did not vary with regional butterfly abundance, though overall rate of parasitism did. Details of the experiment suggest that the apparent commensalism occurred because M. cinxia pupae are protected by silk tents whereas M. athalia are exposed, causing locally foraging parasitoids to favour the more accessible host where the two are present together. The local short-term apparent commensalism favouring M. cinxia opposes the landscape scale trend, in which parasitism increases where butterfly density is high. The outcome of this study illustrates short-term apparent commensalism, that host suitability can depend on relative accessibility, and that indirect interactions occurring at different scales may be in opposition.     

Effects of rearing conditions on the parasitism of Tetrastichus brontispae on its pupal host Octodonta nipae

Octodonta nipae (Maulik) (Coleoptera: Chrysomelidae) is currently a serious invasive pest of palm plants in southern China. Although previous studies reported that Tetrastichus brontispae Ferriere (Hymenoptera: Eulophidae) could successfully parasitize the pupae of O. nipae, little is known of the potential for T. brontispae to control this pest. To understand the interaction between T. brontispae and O. nipae, the effects of parasitoid feeding regimes, host age and density, parasitoid age and density, and cold storage on the parasitism of T. brontispae were investigated. Our results indicate that a supply of either glucose or sucrose increased the longevity and fecundity of T. brontispae. The parasitoid preferred one-day-old host pupae and its fecundity increased with increasing host or parasitoid female density. Extended cold storage negatively affected the parasitism of T. brontispae. These results demonstrate how to efficiently raise T. brontispae and will contribute to the effective management of O. nipae.