2003 Fiscal Year Final Research Report Summary
Urgent revaluation on disturbance of the biological diversity and the environmental indicator by introduced dandelions
| Project/Area Number |
14580563
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
環境影響評価(含放射線生物学)
|
|---|
| Research Institution | TOKYO GAKUGEI UNIVERSITY |
|---|
Principal Investigator |
OGAWA Kiyoshi TOKYO GAKUGEI UNIVERSITY, EDUCATION, ASSOCIATE PROFESSOR, 教育学部, 助教授 (70133113)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
MORITA Tatsuyoshi NIITAGA UNIVERSITY, EDUCATION and HUMAN SCIENCE, PROFESSOR, 教育人間科学部, 教授 (30115084)
|
|---|
| Project Period (FY) |
2002 – 2003
|
| Keywords | dandelion (Taraxacum) / hybrid / native species / introduced species / seed germination / election of growth site / bio-diversity / environmental indicator |
|---|
| Research Abstract |
The method of distinguishing the crossbreed of Japanese diploid and introduced dandelion was developed through combining analysis of chloroplast DNA marker, nuclear DNA marker and relative amounts of DNA by flow site meter. Results of survey in Niigata Pref. and Tokyo were as follows; on Taxaxacum officinale, there were three types of crossbreeds, triploid, tetraploid and the type of mono sexual reproduction with male nucleus. In Niigata, tetraploid hybrid accounted for 49% and pure introduced type did only 18%. In Tokyo, triploid accounted for 57% and pure type was of 12%.
Thermo-germination of seeds from a population just introduced into Japan and hybrids showed the temperature region extended to the high temperature side a little about than the native species, t.platycarpum. The pure type of introduced dandelion and crossbreeds developed the leaves in summer as well as the existing "introduced dandelion". Hybrids appeared in many land-uses without a special selection, while the native species appeared favorably in the farmland and the soil bank, etc. Therefore, a past environmental index of "introduced dandelions" is applicable to hybrids except small case of hybrids with 'various ecological characteristics.
|
