1997 Fiscal Year Final Research Report Summary
Evidence for Introgression in Japanese Evergreen Azaleas on the Basis of Morphological, Phenological and Genome-Analytical Methods
| Project/Area Number |
06404007
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (A)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
園芸・造園学
|
|---|
| Research Institution | Institute of Agriculture and Forestry, University of Tsukuba |
|---|
Principal Investigator |
TAKAYANAGI Kenji University of Tsukuba, Institute of Agriculture and Forestry, Professor, 農林学系, 教授 (20251019)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
SUZUKI Tohru University of Tsukuba, Institute of Agriculture and Forestry.Assistant Professor, 農林学系, 講師 (10272155)
HANDA Takashi University of Tsukuba, Institute of Agriculture and Forestry.Assistant Professor, 農林学系, 講師 (00192708)
ARISUMI Ken-ichi Kagoshima University, Faculty of Agriculture, Professor Emeritus, 農学部, 名誉教授 (40035100)
|
|---|
| Project Period (FY) |
1994 – 1997
|
| Keywords | cpDNA / DNA-polymorphism / evergreen azalea / introgression / morphology / PCR-RFLP |
|---|
| Research Abstract |
For the purpose of ascending the origin of horticultural evergreen azalea cultivars, we focused on the natural populations of Rhododendron sp.in Kyushu. Two distinct evergreen azaleas native to Kyushu, Rhododenron kiusianum and R.kaempferi are distributed separately, and distinguished by their morphological characters. The former is characterized by a dwarf-plant type, small pink-purple flowers and small elliptical leaves, while the latter has a normal plant-type, big red-orange flowers with red blotches and large oblong leaves. R.kiusianum dwells in the volcanic mountain areas above 1,000m alt., while R.kaempferi grows in lower mountain slopes upto 800m alt. In the zone between 800 to 1000m alt., the natural hybrids of two species are distributed showing the intermediate characters of plant-type, leaf size and shape, and various flower colors.
We applied the PCR-RFLP method for specific region of the genome DNA,and finally PCR-R FLP of chloroplast DNA (cpDNA) at the 16S rDNA region dig
… More
ested by Hha I,was effective to distinguish R.kiusianum and R.kaempferi. The band patterns ; 1080bp/420bp were specific to R.kiusianum (kiusianum type) and 950bp/420bp/80bp was unique for R.kaempferi (kaempferi type). We first applied this cpDNA marker to the natural population of the Kirishima Mts. Both populations of R.kiusianum and R.kaempferi showed their specific morphology and cpDNAtype. The hybrid populations revealed various types morphologically and ecologically, but there were two-types of cpDNA,kiusianum and kaempferi type. This indicates that the various extents of hybrid nature were determined by nuclear genes, however there are only two types of cytoplasm (chloroplast) which occured due to natural introgression from one species to another in some earlier times.
There are many other populations similar to the Kirishima Mts.of Kyushu, so we surveyed briefly the natural populations of Unzen, Kuju and Aso Mts. Patterns similar to the Kirishima were also found in these populations except Aso Mts.which showed R.kiusianum with kaempferi type cpDNA even at the higher altitude of the mountain.
These findings suggest the origin of the Japanese horticultural evergreen azalea can be traced back to the natural hybrid population of R.kiusianum and R.kaempferi in Kyushu. Further investigations with the DNA markers of nuclear genome should be followed. Less
|
Research Products
(6 results)
