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Different Host Plant Species (different + host_plant_species)
Selected AbstractsFeeding and breeding across host plants within a locality by the widespread thrips Frankliniella schultzei, and the invasive potential of polyphagous herbivoresDIVERSITY AND DISTRIBUTIONS, Issue 5 2000M. Milne Abstract. Polyphagous insect herbivores could be expected to perform relatively well in new areas because of their ability to exploit alternative resources. We investigated relative abundance patterns of the polyphagous thrips species Frankliniella schultzei, which is characteristically found on plants from many different families, to establish the role of different host plant species in a single locality where the species is not indigenous (Brisbane, south-eastern Queensland, Australia). F. schultzei females and larvae were always present in flowers (where oviposition takes place) and never on leaves of the eight plant species that we surveyed regularly over one year. They were present in flowers of Malvaviscus arboreus in much higher densities than for any other host. F. schultzei females were more fecund and larvae developed faster on floral tissue diets of M. arboreus than on those of other hosts. M. arboreus is therefore regarded as the ,primary' host plant of F. schultzei in the locality that we investigated. The other species are regarded as ,minor' hosts. Available evidence indicates a common geographical origin of F. schultzei and M. arboreus. F. schultzei may therefore be primarily adapted to M. arboreus. The flowers of the minor species on which F. schultzei is also found may coincidentally share some features of the primary host. Adult thrips may therefore accumulate on minor hosts and breed there, but to a lesser extent than on the primary host. The general implications for investigating polyphagous host relationships and interpreting the ecology of these species as generalist invaders are spelt out. [source] Thrips see red , flower colour and the host relationships of a polyphagous anthophilic thripsECOLOGICAL ENTOMOLOGY, Issue 5 2007A. YAKU Abstract 1.,The common blossom thrips, Frankliniella schultzei, is a polyphagous anthophilic species that colonises a wide range of host-plant species across different plant taxa. The environmental cues used by these polyphagous insects to recognise and locate host plants are not known. We therefore determined if colour is an important environmental signal used by F. schultzei to recognise flowers of eight of its more significant host-plant species. 2.,The effect of flower colour on the colonisation of different host plant species by F. schultzei was investigated by collecting and analysing the following: (a) numbers of thrips from different heights and aspects of the primary host plant Malvaviscus arboreus, (b) thrips distribution within flowers of Hibiscus rosasinensis, (c) colour reflectance from flowers of eight different host-plant species, and (d) reflectance from different coloured sticky traps and the number of thrips trapped on them at different times of the day and on different dates. 3.,The results indicate that: (a) the thrips (both sexes) concentrate towards the top of the primary host plant M. arboreus and are not distributed differentially according to sunny or shady aspect of the plant, (b) the number of female thrips on H. rosasinensis was higher in anthers compared to petals (corolla) and the basal parts of the flower, and males were as numerous on the petals as were females, and (c) there is a common floral reflectance pattern (but with different intensities) across the eight host plant species, mainly in the red part of the spectrum (600,700 nm). 4.,Results of colour sticky trapping show that red attracts more female thrips compared to any other colour and that most were caught between 09.00 and 11.00 hours. By contrast, more male thrips were trapped between 07.00 and 09.00 hours. Males were more evenly distributed across the different colours but the highest numbers were associated with the yellow traps. 5.,The higher densities of thrips at the top of their host plant may be related to the early morning (07.00,11.00 hours) activity of the thrips, when the top portions of the plant are more exposed to sunlight. The sex-related distributions of F. schultzei thrips across time, coloured sticky traps, and various parts of the flowers seem to be related to mating swarm formation by the males, on the one hand, and the relative frequency and intensity of the use of M. arboreus by the females, on the other, as a feeding and oviposition site. Frankliniella schultzei females respond more strongly to red than to any other colours, so it is predicted that the spectral properties of colour recognition by this species will correlate with the predominant red reflectance of its primary host, M. arboreus, and that there may well be a sex-related difference in colour recognition within this species. [source] Host shifting by Operophtera brumata into novel environments leads to population differentiation in life-history traitsECOLOGICAL ENTOMOLOGY, Issue 5 2003Adam J. Vanbergen Abstract., 1. Operophtera brumata L. (Lepidoptera: Geometridae), a polyphagous herbivore usually associated with deciduous trees such as oak Quercus robur L., has expanded its host range to include the evergreen species heather Calluna vulgaris (L.) Hull and, most recently, Sitka spruce Picea sitchensis (Bong.) Carrière. 2. Phenology, morphology, and survival of O. brumata were measured at several life-history stages in populations from the three different host plant communities sampled from a range of geographical locations. The data were used to test for population differences, reflecting the marked differences in host-plant secondary chemistry, growth form, and site factors such as climate. The hypothesis that spruce-feeding populations originated from populations feeding on moorland, commonly sites of coniferous afforestation, was also tested. 3. Altitude, not host plant species, was the major influence on the timing of adult emergence. An effect of insect population independent of altitude was found, implying that additional unidentified factors contribute to this phenological variation. Larval survival and adult size varied between populations reared on different host plant species. Survival of larvae was affected negatively when reared on the novel host plant, Sitka spruce, versus the natal plant (oak or heather) but oak and heather-sourced insects did not differ in survivorship on Sitka spruce. 4. Host range extension into novel environments has resulted in population differentiation to the local climate, demonstrating that host shifts pose challenges to the herbivore population greater than those offered by the host plant alone. The hypothesis that Sitka spruce feeding populations have arisen predominantly from moorland feeding populations was not supported. [source] Faunal make-up, host range and infestation rate of weevils and tephritid flies associated with flower heads of the thistle Cirsium (Cardueae: Astaraceae) in JapanENTOMOLOGICAL SCIENCE, Issue 4 2004Akinori NAKAMURA Abstract From 1988 to 1998, we collected flower heads of 39 thistle taxa (35 taxa of Cirsium, one species each of Breea, Synurus, Saussurea and Arctium; Cardueae; Astaraceae) in Japan, mainly from Hokuriku and other parts of central Honshu, and kept them in the laboratory to breed weevils and tephritid flies, the core fauna. We report the faunal make-up, host plants, geographic distribution and the attack levels of the insects. Results indicated that (i) three Larinus species (Curculionidae) and three species of tephritid flies (Tephritis, Urophora and Xyphosia) comprised the core fauna; (ii) two insect species belonging to the same taxonomic group (either Curculionidae (Larinus) or Tephritidae) tended to use different host plant species; (iii) two sympatric Larinus species (L. latissimus and L. meleagris) segregated the host plants seasonally in central Honshu (Cirsium blooming in spring and autumn, respectively); and (iv) two tephritid fly species, Xyphosia punctigera and Urophora sachalinensis, segregated geographically (the former on the Japan Sea side and the latter on the Pacific Ocean side). In comparison with their European counterparts, the weevils and tephritids of the Japanese Cirsium are characterized by a lower species richness and a lower degree of specialization in usage of the thistle flower heads, with gall-formers being distinctly under-represented, and callus tissue-feeders being absent. This reflects the fact that Japanese thistles are so closely related that hybridization frequently occurs, and also that the thistles have had a short history of interaction with the insects since the thistles' arrival in Japan. [source] Glutathione S-transferases in the adaptation to plant secondary metabolites in the Myzus persicae aphidARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 3 2005Frédéric Francis Abstract Glutathione S-transferases (GST) in insects play an important role in the detoxification of many substances including allelochemicals from plants. Induction of GST activity in Myzus persicae in response to secondary metabolites from Brassica plants was determined using different host plant species and confirmed using artificial diet with pure allelochemicals added. The 2,4-dinitro-1-iodobenzene (DNIB) was found to be a useful substrate for identifying particular GSTs in insects. GSTs from M. persicae were purified using different affinity chromatography columns and related kinetic parameters were calculated. GST isoenzymes were characterised using electrophoretic methods. Although SDS-PAGE results indicated similarity among the purified enzymes from each affinity column, biochemical studies indicated significant differences in kinetic parameters. Finally, the GST pattern of M. persicae was discussed in terms of insect adaptation to the presence of plant secondary substances such as the glucosinolates and the isothiocyanates, from Brassicaceae host plants. Arch. Insect Biochem. Physiol. 58:166,174, 2005. © 2005 Wiley-Liss, Inc. [source] | ||||||||||