Search results for "PTE"
showing 10 items of 2238 documents
<strong>The mesothoracic wings of Afrotropical Scutelleridae (Hemiptera: Heteroptera): morphology and taxonomic significance</strong>
2013
Mesothoracic wings have been examined and compared in 32 species representing 20 genera of Afrotropical Scutelleridae. Morphological characters of the corium are described. Three main types of mesothoracic wing venation patterns can be recognized. The taxonomic significance of forewing characters in Scutelleridae is briefly discussed.
Molecular phylogeny of Iberian Fordini (Aphididae: Eriosomatinae): implications for the taxonomy of generaFordaandParacletus
2009
Mediterranean representatives of the galling aphid tribe Fordini (Hemiptera: Aphididae: Eriosomatinae) are usually grouped under the subtribe term Fordina. Aphids within Fordina display two-year life cycles, alternating between Pistacia shrubs, where they induce conspicuous galls, and roots of Poaceae species. The high number of morphs present in a given species, the lack of knowledge of the complete cycle in some species, and the similarity between homologous morphs observed in different species pose many taxonomic problems in this group. We present results of a survey to elucidate the phylogenetic relationships among Fordini species present in the Iberian Peninsula and the Canary Islands.…
Kairomonal effect of walking traces from Euschistus heros (Heteroptera: Pentatomidae) on two strains of Telenomus podisi (Hymenoptera: Scelionidae)
2003
. The semiochemical cues used by geographically isolated strains of the parasitoid, Telenomus podisi (Ashmed), to find eggs of the stink bug Euschistus heros were investigated. Two strains of Te. podisi, maintained on eggs of a South American host (E. heros) were studied. One parasitoid strain originated from specimens collected near Brasilia, Brazil (SA strain), and a second strain originated from specimens collected at Beltsville, Maryland (NA strain). Cold tolerance tests of adults from the NA and SA Te. podisi strains, analyses of the cuticular hydrocarbons between the two strains, and crossing experiments between strains each indicated consistent differences between the NA and SA stra…
Source of the host marking pheromone in the egg parasitoid Trissolcus basalis (Hymenoptera: Scelionidae).
2001
After oviposition, Trissolcus basalis females always mark the host's surface, depositing host marking substances for herself and to warn other ovipositing females. The perception of these host marking substances, probably through the antennae, can induce the female to leave and seek healthy hosts. Parasitoid females exposed to conspecific parasitized egg masses left the host egg masses significantly more often than when exposed to non-parasitized egg masses. More egg mass leaving behavior also was observed when the egg masses were treated with Dufour's gland secretion but not when treated with secretion from the common oviducts. The common oviduct has a secretory epithelium that produces el…
Morphology and function of the sutures in the dermal skull roof of Discosauriscus austriacus Makowsky; 1876 (Seymouriamorpha; Lower Permian of Moravi…
1995
Abstract Sutural patterns in the dermal skull roof were among others studied in Discosauriscus austriacus (Seymouriamorpha) and Onchiodon labyrinthicus (Temnospondyli). Main sutural structures are defined as lamellae; shelves; vertical walls; and grooves. These types have different functional manifestations. The basic pattern is described for Discosauriscus austriacus. Similarities of patterns in taxa not closely related are most likely a result of convergence. Intraspecific variability is generally low but can be observed during ontogeny. The patterns of subjacent areas in Eusthenopteron foordi (Osteolepiformes) are very similar to Discosauriscus austriacus. It is shown that sutural morpho…
Antifeedant activity of neo-clerodane diterpenoids from Teucrium fruticans and derivatives of fruticolone
1999
The antifeedant activity of three neo-clerodane diterpenoids, fruticolone, isofruticolone and fruticolide from Teucrium fruticans was assessed using larvae of Spodoptera littoralis. Isofruticolone was one of the most potent of the Teucrium derived neo-clerodanes. Chemical modification of functional groups on fruticolone showed that its activity could be enhanced.
Structure-immunogenicity relationship of kresoxim-methyl regioisomeric haptens
2013
Kresoxim-methyl was one of the two first strobilurins to be discovered, and nowadays it is widely used as an antifungal agent in crop protection. Because of its low molecular weight and negligible structural complexity, the generation of antibodies to kresoxim-methyl noticeably requires the preparation of functionalized haptens. In this study, the introduction of a hydrocarbon spacer arm at the aromatic moieties of the target molecule was carried out by a convergent strategy based on the Sonogashira cross-coupling reaction, and functionalized linkers of the same length were also tethered to the aliphatic toxophore group by the O-alkylation reaction. Evaluation of the immune response, in ter…
A diterpenoid with antifeedant activity from Scutellaria rubicunda
1999
Abstract Two diterpenoids have been isolated from Scutellaria rubicunda subsp. linneana : (11 S ,13 S ,15 R and S , 16 R ,19 S )-6 α -acetoxy-19-tigloyloxy-2 α ,19;4 α ,18;11,16;15,16-tetraepoxy-neo-clerodan-15-ol (scutecyprol B) and (11 S ,13 S ,15 R and S , 16 R ,19 S )-6 α -acetoxy-2 α ,19;4 α ,18;11,16;15,16-tetra-epoxy-neo-cleroda-15,19,diol (scutalbin C). Both compounds were tested for antifeedant activity against larvae of some species of Lepidoptera. Scutecyprol B shows potent activity at 100 ppm.
4-Hydroxy-5-methyl-3(2H)-furanone and 4-Hydroxy-2,5-dimethyl-3(2H)-furanone, Two Components of the Male Sex Pheromone ofEurycotis floridana(Walker) (…
1993
In Eurycotis floridana, male calling behavior is associated with the sex pheromone released by the anterior part of tergites. 2, 7, and 8. Glandular extracts of tergite 7 revealed a characteristic odor of caramel which is attractive at a distance for the females. We identified the two compounds responsible for this odor, 4-hydroxy-5-methyl-3(2H)-furanone and 4-hydroxy-2,5-dimethyl-3(2H)-furanone. These compounds are known to be very important as flavor components of foods, but this is the first time that they have been. identified as natural insect products. Various amounts of the identified compounds were tested, and their biological function is discussed.
A New Species ofTelenomusHaliday (Hymenoptera: Scelionidae) Associated with Egg Batches of the Pine Processionary Moth,Thaumetopoea pityocampa(Dennis…
2009
Telenomus thaumetopoeae Buhl sp. n. is described from northeastern València (Peninsular Spain) taking as starting point females parasitizing the egg-batches of the Pine Processionary Moth, Thaumetopoea pityocampa (Dennis et Schiffermüller, 1775). Its morphological affinities with the most closely related species and parasitism data are offered.