The PennState/Toru\'n Center for Astronomy Search for Planets Around Evolved Stars. Basic parameters of a sample of evolved stars

The objective of the PSU/TCfA Search for Planets Around Evolved Stars is to study evolution of planetary systems in the stellar evolution timescale. For such an analysis precise physical parameters of the hosts of the planetary systems are essential. In this paper we present an attempt to obtain basic physical parameters for a sample of evolved stars observed within our survey with the High Resolution Spectrograph of the Hobby-Eberly Telescope.Comment: 2 pages, to appear in "Extreme Solar Systems", 2007 ASP Conference Series, eds. Debra Fischer, Fred Rasio, Steve Thorsett and Alex Wolszcza

Diversity and abundance of frugivorous drosophilids and their parasitoids in Bogor, Indonesia

The diversity, abundance and association of frugivorous drosophilids and their parasitoids were studied in Bogor, Indonesia (tropical region), and compared with the results in Iriomote-jima (subtropical region) and Tokyo (temperate region). In the collections of adult drosophilid flies by traps baited with banana in wooded areas, the number of commonly observed frugivorous drosophilid species (i.e. species that occupied more than 0.5% of total drosophilid samples) was 10 in Bogor and nine in Iriomote-jima, more than in Tokyo (six species), probably reflecting the high diversity and abundance of fruits. The rate of parasitism was very high in Bogor, especially in species of the Drosophila ananassae and immigrans species groups. The diversity of parasitoids attacking frugivorous drosophilids was higher in Bogor and Iriomote-jima than in Tokyo, possibly due to the high species diversity of host drosophilids. Parasitoids generally showed wider latitudinal distributions than drosophilids. No remarkable difference was observed in the host range among tropical, subtropical and temperate parasitoids

Weak parasitoid-mediated apparent competition between two Phyllonorycter (Lepidoptera: Gracillariidae) leaf miner species on a deciduous oak Quercus dentata

Parasitoid assemblages and the rates of parasitism on tissue-feeding larvae of two Phyllonorycter leafminer species, P. persimilis and P. leucocorona, were studied from the autumn generation in 2002 to the summer generation in 2005 to understand whether parasitoids mediate interactions of the two leaf species. Fourteen species of parasitoids emerged from P. persimilis and 11 species emerged from P. leucocorona. The parasitism rate was high; i.e., 24.1-92.6% in P. persimilis and 58.9-81.7% in P. leucocorona. Thus, parasitism was a major mortality factor in the present Phyllonorycter species. The parasitoid composition was distinctly different between the two host species, although most parasitoids were able to parasitize both leafminer species. The analysis based on the quantitative parasitoid overlap revealed that the present parasitoids could mediate interactions between the present leafminer species, but their effects would be weak. This is attributable to that most parasitoids preferentially parasitize either of the leafminer species

Altitudinal patterns of abundances and parasitism in frugivorous drosophilids in west Java, Indonesia

Abundances and parasitism rates of frugivorous drosophilid flies were studied in three localities at altitudes of 250-1350m in and near Bogor, Indonesia. The drosophilid and parasitoid species were classified into four groups: low-altitude species, high-altitude species, species abundant at a mid-altitude location and species occurring rather evenly from low to high locations. The ananassae and immigrans species groups were major drosophilids collected. All species of the ananassae species group were more abundant at lower altitudes, and the parasitism rate in this species group decreased with increasing altitude. Thus, the host abundance seems to affect the parasitism rate. On the other hand, the rate of parasitism in the immigrans species group showed no apparent relation with altitude or density, possibly due to the fact that species of this species group varied in altitudinal distribution. It is also suggested that the diversity of drosophilid species affects the composition of parasitoid species

Toxicity of venom of Asobara and Leptopilina species to Drosophila species

The Drosophila parasitoid Asobara japonica Belokobylskij (Hymenoptera: Braconidae) has highly toxic venom that kills host larvae if its injection is not followed by an injection of lateral oviduct components along with egg-laying. In the present study, the venoms of seven other Drosophila parasitoids (Asobara rossica, Asobara rufescens, Asobara pleuralis, Leptopilina heterotoma, Leptopilina japonica, Leptopilina ryukyuensis, and Leptopilina victoriae) are tested against three kinds of Drosophila species (i.e. Drosophila species that are suitable as host for focal parasitoids, those that are resistant to the parasitoids, and a cosmopolitan species, Drosophila simulans). Venoms of the three Asobara species are not toxic to any of Drosophila species, whereas those of the four Leptopilina species are toxic to some Drosophila species. The toxicity of venom varies among Leptopilina species, and the susceptibility to venom also varies among host Drosophila species. Furthermore, toxicity and paralytic effects of venom are not correlated. Because the toxicity of venom is not adaptive for parasitoids, it may be an inevitable side effect of some components that play an essential role in parasitism

Effects of Asobara japonica venom on larval survival of host and nonhost Drosophila species

Ovipositing Asobara japonica females inject venom (containing paralysis-inducing factors) immediately after the insertion of their ovipositors into Drosophila larvae, and lay eggs a little later. Interruption of their oviposition behaviour before egg laying causes high larval mortality in host Drosophila species, while normal oviposition does not. This suggests that venom of this parasitoid is toxic to larvae of these host species but its toxicity is suppressed by factor(s) provided by parasitoid females at the time of laying egg or by parasitoid embryos developing in the hosts. On the other hand, venom does not show toxicity to larvae of non-host Drosophia species. Possible functions of venom are discussed

Seasonal life cycles and resource uses of flower- and fruit-feeding drosophilid flies (Diptera: Drosophilidae) in central Japan

Seasonal life cycles and resource uses of flower- and fruit-feeding drosophilids (Diptera: Drosophilidae) were studied at low to high altitudes in central Japan to understand their adaptation to seasonal changes of environmental conditions. Drosophila unipectinata and D. oshimai specialized to flowers, D. suzukii and D. subpulchrella depended almost on fruits, while D. lutescens, D. rufa, D. auraria, D. biauraria and D. sternopleuralis used both of them. It was assumed that D. unipectinata moved from low to high altitudes in June while D. oshimai, D. suzukii and D. subpulchrella in July. Migration of D. unipectinata is considered as a means to avoid summer heat or exploit early-summer resources at high altitudes. On the other hand, D. oshimai, D. suzukii and D. subpulchrella have the capacity to pass the summer at low altitudes, and therefore their migration is assumed as a means to escape from resource-poor conditions in summer at low altitudes or exploit resources at high altitudes. The generalist species, D. lutescens, D. rufa, D. auraria, D. biauraria and D. sternopleuralis, would not perform such extensive movements between low and high altitudes. They may pass the summer at low or mid altitudes depending on accidentally fallen immature fruits and/or some other resources such as decayed leaves