1. トミヨ保護池におけるトミヨ属Pungitius淡水型と雄物型の交雑
- Author
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KAWAMATA, Kunihiko, SUGIYAMA, Hideki, MARUYAMA, Ryoko, TOMITA, Tami, EDO, Mieko, TAKEDA, Mai, and NITTA, Takahiro
- Subjects
Fresh water type ,reproductive isolation ,fungi ,Pungitius ,Omono type - Abstract
Artificial pond was built for a substitute habitat of nine spine stickleback (Omono type) lose habitat for paddy fields rezoning on Yuzawa city Akita, In 2000, 20 Omono type fishes were released in the artificial pond with Fresh-water type unknown pathway of entry. In 2001, it was confirmed that there were first filial hybrid (F_1 hybrid) between Omono and Fresh-water types. We examined the proportions of each types, Omono type, Fresh-water type and hybrid, in the artificial pond by isozyme analysis from 2001 to 2006. Unlike the population of Hiraka, reproductive isolation between Omono and Fresh-water types was defective, so around 10% F_1 hybrids come out. It was suggested that these male F_1 hybrids were reciprocally sterile as in the case of Fresh-and Brackish-water types. Although it was possible that third filial generation was exist at least, it was unclear about forth and later filial generation by the limit of isozime analysis. Although the artificial pond was built to preserve Omono type, mixing Fresh-water type resulted number of Omono type decreases and Fresh-water type increases. No such cases have been reported in the ponds coexisting Omono and Fresh-water types in Hiraka. It suggests that degree of completion in reproductive isolation is different among each populations.
- Published
- 2013