survey of scale insects of ornamental plants in alexandria governorate, egypt.this investigation covers a survey of the scale insects associating with some ornamental plants at three chosen public gardens as well as at the experimental farm of the agricultural research station in alexandria governorate, egypt. a total of nineteen scale insect species belonging to sixteen genera related to four families of the super-family coccoidea were found infesting eighteen ornamental plants during the period from april, 1998 up to march, 1999. these species are: family: asterolecanii ...200112425080
a survey of scale insects (sternorryncha: coccoidea) occurring on table grapes in south africa.increasing international trade and tourism have led to an increase in the introduction of exotic pests that pose a considerable economic threat to the agro-ecosystems of importing countries. scale insects (sternorryncha: coccoidea) may be contaminants of export consignments from the south african deciduous fruit industry to the european union, israel, united kingdom and the united states, for example. infestations of immature scale insects found on south african fruit destined for export have re ...200920050816
ultrastructural and cytochemical characterization of brown soft scale coccus hesperidum (hemiptera: coccidae) infected by the lecanicillium lecanii (ascomycota: hypocreales).the ultrastructural and cytochemical characterization of the brown soft scale, coccus hesperidum l. (hemiptera: coccidae) infected by the hyphomycete lecanicillium lecanii (zimmermann) gams & zare, belonging to the phylum ascomycota and order hypocreales, was investigated by light, scanning and transmission electron microscopy. gold cytochemistry was used to label chitin in the cuticle of the scale insect. the results revealed that the pathogenic fungus, l. lecanii generally infected by penetrat ...201120863711
the role of honeydew in host searching of aphid hyperparasitoids.foraging in many insect parasitoids is mediated by chemicals associated with hosts. for example, honeydew, the feces of feeding aphids, induces and/or prolongs searching behavior of aphid parasitoids. in the laboratory, we tested if aphid hyperparasitoids, which belong to a higher trophic level, also rely on aphid honeydew to locate their hosts. we used the potato aphid. macrosiphum euphorbiae, the primary parasitoid, aphidius nigripes, and four hyperparasitoids, asaphes suspensus, dendrocerus c ...200415112724
sex ratios in field populations of two parasitoids (hymenoptera: chalcidoidea) of coccus hesperidum l. (homoptera: coccidae).we tested several assumptions and predictions of host-quality-dependent sex allocation theory (charnov et al. 1981) with data obtained for the parasitoid metaphycus stanleyi compere on its host, brown soft scale (coccus hesperidum l.), in a california citrus grove and in the laboratory. scales ceased growing after parasitization by m. stanleyi. thus, m. stanleyi may gauge host quality (=size) at oviposition. host size positively influenced adult parasitoid size, and parasitoid size in turn influ ...199828307520
[host-parasite interactions in coccus hesperidum l. (hom. coccidae) and its parasite coccophagus scutellaris dalman (hum. aphelinidae). iii. effect of the number of hosts and their sanitary conditions on the oviposition of the parasite].intensity of egg laying of coccophagus scutellaris depends on the number of hosts available. it is found to be more important when the female has several hosts. furthermore a better distribution of eggs is observed in that case. when parasited and parasiteless hosts are available, the female of coccophagus deposits more eggs on the latter. this discriminating ability in relation to number and kinds of hosts available is discussed.20067283545
[host-parasite interactions between coccus hesperidum l. (hom. coccidae) and its parasite coccophagus scutellaris dalman (hym. aphelinidae)].the eggs laid in the host gut will develop normally. the larva resulting from those eggs penetrate the hemocele through the gut wall. the structure of the cells near the entry point is not affected because of the continuous renewal of those cells. on the other hand, development of the ovaries is most seriously affected. in fact, ovogenesis is stopped and vitellogenesis slowed down. but this phenomenon is related to the initial level of ovary development. if the attack takes place when the host i ...2006747455
carbohydrate composition of the honeydew of coccus hesperidum l.: evidence for the existence of two new oligosaccharides. 195513269130
genetic diversity of armored scales (hemiptera: diaspididae) and soft scales (hemiptera: coccidae) in chile.scale insects (sternorrhyncha: coccoidea) are one of the most invasive and agriculturally damaging insect groups. their management and the development of new control methods are currently jeopardized by the scarcity of identification data, in particular in regions where no large survey coupling morphological and dna analyses have been performed. in this study, we sampled 116 populations of armored scales (hemiptera: diaspididae) and 112 populations of soft scales (hemiptera: coccidae) in chile, ...201728515435
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