The Study On The Genetic Diversity Of P.hyalocranius

Salangid is a kind of small commercially important fish. P. hyalocranius and N. taihuensis belong to two different species. Since 1995, it has been hard to fulfill effective management and protectation for the germplasm resources of salangids, due to massive zygotes transplantation and the mixture of the individuals from various water bodies.For the purpose of studying the genetic diversity of P. hyalocranius and comparing the genetic differentiation from different water bodies to give theoretical reference for transplantation, propagation, management and protectation of the germplasm resources, the genetic diversity of P. hyalocranius from Taihu, Huanggang, Jinnan, Yuzhuang and Daihai populations was analyzed with isozyme and RAPD methods, respectively. The genetic diversity from Taihu, Huanggang, and Daihai populations was analyzed with AFLP method. Meanwhile, the genetic diversity of Taihu N. taihuensis and the comparison with P. hyalocranius were performed isozyme method.Seven isozymes and the Prot. of 262 individuals from five populations in P. hyalocranius and Taihu N. taihuensis were examined with isozyme method. 16 loci were detected. Based on 0.99 criterion of polymorphism, the proportion of polymorphic loci were 0%-12.5%. Based on 0.95 criterion, the proportion of polymorphic loci were 0%. The average expected heterozygosity was 0-0.0057. The proportion of polymorphic loci and the average expected heterozygosity of Huanggang population were 12.5% and 0.0057, respectively, while those of Daihai population were 6.3% and 0.0015, respectively. The Nei' genetic distance among P. hyalocranius were 0.000010- 0.000103, which were lower relatively compared with other fish species. Among Taihu, Huanggang, and Daihai populations, the genetic distance of Daihai and Huanggang was 0.000010, of Daihai and Taihu was 0.000052, and of Huanggang and Taihu was 0.000070, which had the largest value. If using 0.99 and 0.95 criterion, the proportions of polymorphic loci of Taihu N. taihuensis were 18.8% and 12.5%, repectively. The average expected heterozygosity were 0.0178. The degree of diversity of Taihu N. taihuensis was higher than P. hyalocranius. The differences of a-GPD-4 *, LDH-1*, LDH-2*, LDH-3 and PGM* were found between P. hyalocranius and N.