|Budget Amount *help
¥13,500,000 (Direct Cost : ¥13,500,000)
Fiscal Year 1999 : ¥3,000,000 (Direct Cost : ¥3,000,000)
Fiscal Year 1998 : ¥2,900,000 (Direct Cost : ¥2,900,000)
Fiscal Year 1997 : ¥7,600,000 (Direct Cost : ¥7,600,000)
Astigmata is a suborder of acari and consists of a group of mites with poor morphological characteristics. Most species are white in color and oval with less than 1 mm in body length, and therefore, skilled technique are required for species identification, after mounting each specimen on a slide glass for microscopic observation. On the other hand those astigmatid mites and also a parts of Oribatida possess a pair of well developed excretory glands (so-called opisthonotal gland or oil gland), from which total 50 volatile compounds functioning as the alarm, aggregation and sex pheromones and compounds with unknown functions are identified from more than 50 species. During studies of mite's exudates, these profiles of compounds were noticed to be characteristic to each species, even morphological indexes are similar. Therefore, GC profiles from 101 species (including strains) of astigmata and 23 species (including strains) of Oribatida were collected and compared each other, along with
nucleotide sequence analyses of chromosomal ITS-II region by PCR, subsequent cloning to E. coli and DNA analyses. ITS-II regions of Astigmata and Oribatida consisted of 300-600 nucleotide. As a result, species differences were directly correlated to those differences of GC profiles with minor exceptions to be further examined. Several strains with minor differences of GC profiles due to quantitative variations of components were confirmed as the same species, based on their ITS-II base sequences. Although there was a few exceptional cases to be further examined, mite's identification based on GC profiles were demonstrated to be an easy and versatile method, and objection of the present project has been accomplished.
During the present study I have succeeded to develop an agar medium to raise mites easily and aseptically. About two third of mite's stock culture were successively maintained by the agar medium. Total 11 papers dealing with identifications of mites pheromones (alarm and sex pheromones) and new compounds as the natural product chemistry were also published.