1990 Fiscal Year Final Research Report Summary
Study on Reproduction, Settlement, and Boring of the Boring Polychaeta Polydra
| Project/Area Number |
63480066
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
General fisheries
|
|---|
| Research Institution | Tohoku University |
|---|
Principal Investigator |
MATSUTANI Takeshige Tohoku Univ., Fac. of Agr. Associate Prof., 農学部, 助教授 (90134030)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
IMAJIMA Minoru Nat. Sci. Mus., Dep. of Zool., Chief, 動物研究部, 部長 (30000110)
OSADA Makoto Tohoku Univ., Fac. of Agr. Assistant, 農学部, 助手 (30177208)
|
|---|
| Project Period (FY) |
1988 – 1990
|
| Keywords | Polydora / Settlement / boring / scallop / Reproduction |
|---|
| Research Abstract |
Polydra has been reported to cause damage to scallops. Therefore we investigated reproduction, settlement, and boring of the boring Polychaeta Polydra inhabiting the scallop Patinopecten yessoensis in Abashiri Bay, in order to get some information about extermination of Polydra. Firstly, We made clear species of Polydra boring scallops in Abashiri Bay. Aa new species Polydora variegata was dominant all the year round in Abashiri Bay. So, we investigated in detail the reproductive system, and settlement and boring process of P. Variegata. The sawning period, frequency of brooding female, number of batchs per spawning period and number of eggs per batch of P. Variegata was ascertained. Secondly, oogenesis of P. Variegata was studied histologicaly. Young oocytes in ovary grow until 25-30 mum in the ovary, then dropped into the body cavity and began to accumulate york. Morphological characteristics of the larvae of P. Variegata was observed in detail. Thirdly, we investigated infestion of the Japanese scallop in Hokkaido and Tohoku district, and, compared with the infestion by Polydora in Aabashiri Bay. The larvae of P. Variegata serect the shells of living scallops.
These results obtained from this study supplied the important informations about defence methods for the settlement and boring in P. Variegata.
|
