旭硝子財団助成研究成果報告2020

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58西川　完途76Kanto NISHIKAWA77ThanyanuchKriangripipat78SiriluxPoompradub熱帯・亜熱帯アジアにおけるシロアリ食の小型脊椎動物群集の自然史解明と炭素循環への影響 （2018採択）Investigation on natural history of termite-eating small vertebrates fauna and its effect on carbon cycle in tropical and subtropical Asia(Project 2018)Sequencing and Characterization of a Hypovirulence dsRNA Virus from an Oomycete (Project 2017)Development of Natural Rubber Composite for Carbon Dioxide Adsorbent Material (Project 2018)旭硝子財団　助成研究成果報告（2020）A pythiaceous fungus, isolate R84, contained three dsRNA segments with approximately 8.0, 3.7 and 2.3 kilobases was isolated from rubber tree with symptoms of abnormal leaf fall from eastern Thailand. Phytophthora spp. were the only known agent of leaf fall disease in Thailand. The isolate R84 failed to sporulate on media commonly used for sporulation in Phytophthora. This suggested that the virus might confer the trait. However, phylogenetic analysis based on sequences of the internal transcribed spacer rDNA region showed that the isolate R84 was Phytopythium cucurbitacearum. Virus curing using single zoospore isolation method showed that strain R84 had at least 2 viruses. The growth rate, sexual and asexual reproduction, hymexazol resistance and leaf infection of the isolate R84 suggested that the dsRNA infection was in a symptomless manner. This was the first report of dsRNA elements in Phy. cucurbitacearum and of Phy. cucurbitacearum on para rubber trees.Herein this research, the significant challenge of CO2 capture and recent advantages of natural rubber (NR) to produce NR adsorbent materials was focused. To improve CO2 adsorption capacity of NR, the silica (SiO2) based adsorbents was introduced. NR latex was modified by a diallylamine using tert-butyl hydroperoxide 熱帯・亜熱帯の動物の中で最大級のバイオマスを誇るシロアリを地中性の両生類や爬虫類がどれくらい捕食しており，果たしてシロアリ食に特化した種がいるのか，マレーシア・サラワク州と沖縄において調査を行った．その結果，両生類のヒメアマガエル科，ヌマガエル科，ヌメアシナシイモリ科，そして爬虫類ではスキンク科から，地中性または半地中性でシロアリを高頻度で捕食している種の存在していることが明らかとなり，トカゲに関しては新種記載を行った．上記の結果は，地中性の両生類や爬虫類相はフロンティアであり，シロアリへの物質循環の大きさも全く解明されていないことを示しており，世界的にみても大きな発見であると言える．In order to examine how much the subterrestrial amphibians and reptiles feed and specialized to feed ter-mites, which have largest biomass in the subtropical and tropical animals, we conducted surveys in Sarawak, Malaysia and Okinawa. We found fossorial or subfossorial animals of amphibians (Microhylidae, Dicroglos-sidae, Ichthyophiidae) and reptiles (Scincidae) that often fed termites and described one new species of the subfossorial skink. These findings indicate that we still do not understand the subterrestrial herpetofauna well and their impact on resource renewal via the termite activity.