UJI PREFERENSI TUMBUHAN INANG BEBERAPA POPULASI KUMBANG LEMBING Epilaehna. aff. emarginata (COLEOPTERA; COCCINELLIDAE; EPILACHNINAE)

Epilaehna sp. aff. emarginata had been considered as a specialist on Mikania micrantha (Compositae). However, recently its oceurrence on Leucas lavandulifolia (Labiatae) was reported. Preliminary field observations of some beetle populations showed that they had different on the host plant utilizations. However, the result was not sufficient to interpret the food preference of the beetles. These experiments weremade in order to clarify those previous observations.Experiments on adult food preference was investigated under uncontrolled room conditions.Four beetle populations (Bogor, Cibinong, Klaten and Malang) were subjected to choice tests offering Mikania micrantha (Compositae) and Leucas lavandulifolia. These experiments indicated that individual beetle has similar trend on food preference within each population. Bogor and Cibinong populations preferred to feed on both M. micrantha and L. lavandulifolia while. Klaten and Malang populations preferred exclusively on L. lavandulifolia. The populations showed different food preferences on the different geographical conditions of Java

Genome Features of “Dark-Fly”, a Drosophila Line Reared Long-Term in a Dark Environment

Organisms are remarkably adapted to diverse environments by specialized metabolisms, morphology, or behaviors. To address the molecular mechanisms underlying environmental adaptation, we have utilized a Drosophila melanogaster line, termed “Dark-fly”, which has been maintained in constant dark conditions for 57 years (1400 generations). We found that Dark-fly exhibited higher fecundity in dark than in light conditions, indicating that Dark-fly possesses some traits advantageous in darkness. Using next-generation sequencing technology, we determined the whole genome sequence of Dark-fly and identified approximately 220,000 single nucleotide polymorphisms (SNPs) and 4,700 insertions or deletions (InDels) in the Dark-fly genome compared to the genome of the Oregon-R-S strain, a control strain. 1.8% of SNPs were classified as non-synonymous SNPs (nsSNPs: i.e., they alter the amino acid sequence of gene products). Among them, we detected 28 nonsense mutations (i.e., they produce a stop codon in the protein sequence) in the Dark-fly genome. These included genes encoding an olfactory receptor and a light receptor. We also searched runs of homozygosity (ROH) regions as putative regions selected during the population history, and found 21 ROH regions in the Dark-fly genome. We identified 241 genes carrying nsSNPs or InDels in the ROH regions. These include a cluster of alpha-esterase genes that are involved in detoxification processes. Furthermore, analysis of structural variants in the Dark-fly genome showed the deletion of a gene related to fatty acid metabolism. Our results revealed unique features of the Dark-fly genome and provided a list of potential candidate genes involved in environmental adaptation

Distribution and host specificity of the thistle-feeding tortoise beetle Cassida vibex (Coleoptera: Chrysomelidae) in southwestern Hokkaido, northern Japan

The thistle-feeding tortoise beetle Cassida vibex (Coleoptera: Chrysomelidae) is widespread in the Palearctic region. In Japan, this species has been recorded only from the largest island, Honshu. Here we report the occurrence of this species on Hokkaido, the most northern main island of Japan, along with detailed distributional records from the southwestern part of the island (southern Oshima Peninsula) and information on host plants. We also present the results of laboratory experiments on adult feeding preference and larval developmental performance to determine the specificity of C. vibex for four thistle species (Cirsium grayanum, Cir. alpicola, Cir. yezoense and Cir. aomorense; Asteraceae) common in southwestern Hokkaido. Cassida vibex was detected at only four sites among 97 sites investigated on the Oshima Peninsula, in strong contrast to the common occurrence of the congeneric thistle feeder C. rubiginosa (74 of 97 sites). Cassida vibex was found mainly on Cir. alpicola in the wild, but adult beetles showed no feeding preference for this or three other thistle species when given a choice in the laboratory. Larval performance of C. vibex was similar on Cir. alpicola, Cir. yezoense and Cir. aomorense but significantly lower on Cir. grayanum. Since Cir. alpicola often forms large clumps of individual plants, whereas Cir. yezoense and Cir. aomorense are scattered in their habitats, and C. vibex was collected only at sites where there were dense patches of Cir. alpicola, we postulate that the persistence of C. vibex is possible only where a substantial amount of suitable host plants is available

Dynamics of Dark-Fly Genome Under Environmental Selections.

「暗黒バエ」の暗闇適応に関わるゲノム配列の解析 -ゲノムの視点から環境適応のメカニズムに迫る-. 京都大学プレスリリース. 2016-03-09.Environmental adaptation is one of the most fundamental features of organisms. Modern genome science has identified some genes associated with adaptive traits of organisms, and has provided insights into environmental adaptation and evolution. However, how genes contribute to adaptive traits and how traits are selected under an environment in the course of evolution remain mostly unclear. To approach these issues, we utilize "Dark-fly", a Drosophila melanogaster line maintained in constant dark conditions for more than 60 years. Our previous analysis identified 220, 000 single nucleotide polymorphisms (SNPs) in the Dark-fly genome, but did not clarify which SNPs of Dark-fly are truly adaptive for living in the dark. We found here that Dark-fly dominated over the wild-type fly in a mixed population under dark conditions, and based on this domination we designed an experiment for genome reselection to identify adaptive genes of Dark-fly. For this experiment, large mixed populations of Dark-fly and the wild-type fly were maintained in light conditions or in dark conditions, and the frequencies of Dark-fly SNPs were compared between these populations across the whole genome. We thereby detected condition-dependent selections toward approximately 6% of the genome. In addition, we observed the time-course trajectory of SNP frequency in the mixed populations through generations 0, 22, and 49, which resulted in notable categorization of the selected SNPs into three types with different combinations of positive and negative selections. Our data provided a list of about 100 strong candidate genes associated with the adaptive traits of Dark-fly

Redescription of the phytophagous ladybird beetle Henosepilachna diekei and descriptions of two related species from Indonesia (Coccinellidae, Coccinellinae, Epilachnini)

The phytophagous ladybird beetle Henosepilachna diekei Jadwiszczak & Wegrzynowicz was redescribed on the basis of specimens from Indonesia and other south and southeastern Asian countries, and two new species related to it were described as H. nakanoi Matsubayashi & Katakura sp. nov. and H. uenoi Matsubayashi & Katakura sp. nov. Henosepilachna nakanoi is easily discernible from congeners by the unique structure of male and female genitalia. Henosepilachna uenoi has genitalia being nearly identical with H. diekei, but the two species sympatric in Bali are separable by the habitus shape, elytral maculation pattern, and host plants. A phylogenetic analysis based on mitochondrial NADH dehydrogenase subunit 2(ND2) gene sequences also indicated that H. uenoi and H. diekei are genetically distinct, though very close to each other

POTENTIAL ABILITY OF THE SOLANUM-FEEDING LADYBIRD BEETLE HENOSEPILACHNA DIFFINIS (COLEOPTERA; COCCINELLIDAE) TO USE THE INTRODUCED FABACEOUS PLANT CENTROSEMA MOLLE

Host specificity has been a major factor in generating the tremendous diversity of phytophagous arthropods. Studies of adaptation to introduced or invasive plant species provide an opportunity to investigate incipient evolutionary changes in host specificity. We investigated the cryptic ability of the Asian tropical herbivorous ladybird beetle Henosepilachna diffinis to feed on the fabaceous weed "centro", Centrosema molle, which was introduced to Southeast Asia about 200 years ago. In laboratory choice tests using this plant and the normal host plant, Solanum torvum, adults preferred S. torvum to centro, but over half the beetles tested ate leaves of both plants. Furthermore, most first-instar larvae accepted centro during a rearing experiment, and a few of them grew to the third-instar stage, though none reached the final (fourth) instar. Henosepilachna diffinis likely acquired this incomplete acceptability of centro without any direct host-grazer interaction with centro, probably before this weed was introduced to Southeast Asia. Our results further suggest that another Henosepilachna species, H. vigintioctopunctata, might similarly have already acquired an incomplete ability to use centro when this beetle encountered it for the first time, and this triggered a subsequent host-range expansion from solanaceous plants to include centro in various parts of Southeast Asia