埃及黄盾食蚧蚜小蜂在生物防治蚧壳虫中的作用

在埃及,黄盾食蚧蚜小蜂Coccophagus suteelaris(Dalman)是一种有效防治蚧壳虫的寄生蜂,研究中分别用6种蚧壳虫Ceroplastes floridensis Comstock,Coccus hesperidumL.,Pulvinaria floccifera (Westwood),P.psidii Maskell,Saissetia coffeae(Walker)以及S.oleae(Oliver)来饲养黄盾食蚧蚜小蜂,1999－2000年间,在埃及的Beni-Suef,Cairo,Giza,Gharbiya和北海岸等5个地方,C.scutellaris大规模的发生在7－11月间,C.scuteelaris对S.coffeae和S.oleae的最高寄生率分别是发生在1999年11月和8月的26％和22％,因此可以认为,黄盾食蚧蚜小蜂是对两种蚧壳虫有效的寄生蜂。     

Local maladaptation in the soft scale insect Saissetia coffeae (Hemiptera: Coccidae)

Local adaptation has often been documented in herbivorous insects. The potential for local maladaptation in phytophagous insects, however, has not been widely considered. I performed a two-generation reciprocal cross-transplant experiment with the generalist soft scale insect Saissetia coffeae (Hemiptera: Coccidae) on two common species of host plants in rain forest habitat in Costa Rica. In this system, S. coffeae showed significant local maladaptation at the level of the host species. Lineages originally collected from Witheringia enjoyed a strong advantage over those collected from Lomariopsis when both sets of lineages were placed on Lomariopsis; however, when both sets of lineages were raised on Witheringia, their fitnesses were statistically indistinguishable. While some aspects of the biology of S. coffeae may impair its ability to adapt to local selection pressures, scale insects are often locally adapted on fine spatial scales, and local maladaptation is therefore especially surprising. Other documented cases of local maladaptation in parasites appear to be due to evolution on the part of the host. The possibility that hosts or natural enemies may place local genotypes at a disadvantage, producing a pattern of local maladaptation, is one that deserves more consideration in the context of plant-insect interactions.     

Maternal effects in the soft scale insect Saissetia coffeae (Hemiptera: Coccidae)

Effects of maternal environment on offspring performance have been documented frequently in herbivorous insects. Despite this, very few cases exist in which exposure of parent insects to a resource causes the phenotype of their offspring to be adjusted in a manner that is adaptive for that resource, a phenomenon called adaptive transgenerational phenotypic plasticity. I performed a two-generation reciprocal cross-transplant experiment in the field with the soft scale insect Saissetia coffeae (Hemiptera: Coccidae) on two disparate host plant species in order to separate genetic effects from possible transgenerational plasticity. Despite striking differences in quality between host species, maternal host had no effect on overall offspring performance, and I detected no "acclimatization" to the maternal host species. However, there was a significant negative association between maternal and offspring development times, with potentially adaptive implications. Furthermore, offspring of mothers reared in an environment where scale densities were higher and scales were more frequently killed by fungi were significantly less likely to suffer from fungal attack than were offspring of mothers reared in an environment where densities were low and fungal attack was rare. Although S. coffeae does not appear to alter offspring phenotype to increase offspring fitness on these two distinct plant species, it does appear that offspring phenotype may be responding to some subtler aspects of maternal environment. In particular, the possibility of induced transgenerational prophylaxis in S. coffeae deserves further investigation.     

赛阿金小蜂属分类及一新种描述(膜翅目,金小蜂科)

研究了金小蜂科、金小蜂亚科的赛阿金小蜂属Cyr-toptyx Delucchi,1956,描述1新种黄翅赛阿金小蜂Cyrtoptyx flavida sp．nov．及2新纪录种：丽躯赛阿金小蜂C．1ichten—steini(Masi)和实蝇赛阿金小蜂C．1atipes(Masi)。编制了中国赛阿金小蜂属分种检索表。新种黄翅赛阿金小蜂Cyrtop-tyx flavida sp．nov与其它两种的主要区别是：触角各索节与第1棒节均具2轮感觉毛,梗节与鞭节长之和大于头宽。模式标本保存于中国科学院动物研究所动物标本馆。     

Aspects of prey relations in the coccidophagous ladybird <Emphasis Type="Italic">Chilocorus nigritus</Emphasis> relevant to its use as a biological control agent of scale insects in temperate glasshouses

The armoured scale insects Acutaspis umbonifera (Newstead), Pinnaspis buxi (Bouché) (Homoptera: Diaspididae) and the soft scale insects Saissetia coffeae (Walker) and Coccus hesperidum L. (Homoptera: Coccidae) were tested as suitable prey for the ladybird Chilocorus nigritus (F.) (Coleoptera: Coccinellidae), with a view to using the beetle as a biological control agent in UK glasshouses. C. nigritus larvae were able to complete development on all prey species tested and adults were also able to mature eggs on P. buxi, S. coffeae and C. hesperidum (A. umbonifera was not tested in this respect). Prey in ornamental glasshouses and interior landscapes are often diverse and patchily distributed. Thus the effect on the beetle larvae of switching between diaspidid and coccid prey was also examined. Larvae were able to switch from feeding on C. hesperidum to Abgrallaspis cyanophylli (Signoret) (Homoptera: Diaspididae) and vice versa with only minor detrimental effects when compared to those beetles reared throughout on one prey species. Introductions of C. nigritus as eggs, rather than adults are indicated for the control of soft scale species.     

Biology and field performance of gryon clavigrallae (Hymenoptera: Scelionidae), an egg parasitoid of Clavigralla spp. (Hemiptera: Coreidae) in India

The biology and impact of Gryon clavigrallae Mineo, an egg parasitoid of Clavigralla scutellaris Spinola and C. gibbosa (Westwood), was investigated. The calculated developmental threshold temperatures for females and males were 15.6 degrees C and 15.8 degrees C, respectively. Emergence exceeded 94% at temperatures between 22 and 30 degrees C. Adult females lived on average 28-96 days when fed with honey. Without food, adults lived < 6 days. Mean fecundity was 56.4 eggs per female. A significant trend of lower fecundity after longer periods of host deprivation was observed. Gryon clavigrallae females successfully oviposited in host eggs of all ages though eggs < 4 days old were preferred. Total host handling times were significantly longer on C. gibbosa eggs (23.5 min) than on C. scutellaris eggs (12.0 min). Females readily distinguished parasitized from non-parasitized host eggs. Superparasitism was observed when few or no unparasitized eggs were available. Eggs of the two Clavigralla species can be separated by surface structure and condition after eclosion. Clavigralla scutellaris laid significantly larger egg clusters than C. gibbosa (19.9 versus 10.5 eggs per cluster). Gryon clavigrallae was present as soon as the first Clavigralla spp. egg clusters were found on pigeonpea. The percentage of egg clusters parasitized increased early in the season with egg cluster density and remained high (up to 83%) despite fluctuations in host density. Overall, G. clavigrallae parasitized 40 and 58% of C. gibbosa and C. scutellaris eggs. The percentage of egg clusters parasitized and the number of eggs parasitized per cluster increased significantly with egg cluster size. The overall parasitoid sex ratio was highly female biased but varied with the number of eggs parasitized per cluster.     

The role of augmentative releases of indigenous parasitoid Metaphycus lounsburyi (Hymenoptera: encyrtidae) in enhancing the biological control of Saissetia oleae (Homoptera: coccidae) on olive in Egypt

The Mediterranean black scale, Saissetia oleae (Olivier) (Homoptera: Coccidae) is the most important pest of olive in Egypt. Indigenous parasitoid Metaphycus lounsburyi (Howard) (Hymenoptera: Encyrtidae) from different localities in Egypt, were manipulated, reared and mass produced for classical biological control in Egypt, more than 193130 parasitoids were released. Several releases were made between May 1999 to April 2001. Increases of the parasitism from 17.4 to 42.0 and from 6.4 to 19.2 during the first year (1999–2000) and the second year (2000–2001), respectively in the Northern Coast. This parasitoid became established in some of the release sites in El-Arish and Matruh Governorates.     

Partial purification and insecticidal activity of toxic metabolites secreted by a Mucor hiemalis strain (SMU-21) against adults of Bactrocera oleae and Ceratitis capitata (Diptera: Tephritidae)

The secondary metabolites present in the methanol extract of a Mucor hiemalis strain (SMU-21) mycelia, cultured in liquid medium, were evaluated for toxicity to Bactrocera oleae (Gmelin) and Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) adults. Feeding and contact bioassays revealed that the methanol fraction of the crude supernatant was strongly toxic to both species. Symptoms of toxicity developed quickly; lethargy occurred 1-2 h posttreatment, and mortality reached 82-97% after 24 h. Both feeding and contact bioassays showed that B. oleae was more susceptible than C. capitata. Concentrations producing 50% mortality (LC50) to B. oleae and C. capitata after 24 h in feeding bioassays were 0.52 and 1.28 mg/ 0.1 ml diet, respectively, but 34.8 and 64.0 microg/ cm2, respectively, after 4 h in contact bioassays. Solvent partition, precipitation, and chromatographic procedures were used to isolate the active principles from the crude supernatant. These resulted in the isolation of one high-pressure liquid chromatography fraction with insecticidal activity on B. oleae flies equal to the initial crude supernatant.     

苏铁蚧虫及其天敌

通过对我省10县市的调查、采集和鉴定,苏铁蚧虫计有15种,隶属4科、10属。发生最普遍、最严重的是咖啡盔蚧和酱褐圆蚧。天敌有寄生性天敌15种、捕食性天敌6种和寄生菌1种。     

Efficacy of five volatile oils and their mixtures against the soft scale insect, Saissetia coffeae (Walker) (Hemiptera: Coccidae) infesting the Sago palm, Cycas revoluta in Alexandria, Egypt

Five tested plant volatile oils and their mixtures were evaluated for controlling the coccid, Saissetia coffeae (Walker) on growing Sago palms Cycas revoluta in Antoniades public gardens, Alexandria, Egypt. The tested volatile oils at concentration rates of 0.5, 1 and 1.5% (v/v) were: Camphor 20%, Dill 20%, Rose 30%, Peppermint 20% and Clove 30% (v/v). Their mixtures were : Camphor/Peppermint, Camphor/Rose at a rate of 1:1, Camphor/Rose/Peppermint at 1:1:2 rate and Camphor/Rose/Dill at 2:1:1 rate. The results, as a general mean of residual reduction percent for the whole inspection intervals of the test lasted 2 days up to 9 days post treatment, indicated that the superior volatile oils in reducing the insect were both Camphor and Rose, followed by Dill, Peppermint and the least efficient one was the Clove oil. The evaluated mixtures of the volatile oils showed that each of Camphor/Rose/Peppermint, Camphor/Rose and Camphor/Peppermint mixtures attained a higher rank of efficiency against that of the assigned soft scale insect.