Genetic diversity of snakehead fish genus Channa in northeastern Thailand using PCR-RFLP technique

บทคัดย่อ

The objective of this research was to investigate genetic diversity of four species of snakehead fish genus Channa as Channa striata, C. micropeltes, C. gachua and C. lucius in northeastern Thailand using PCR-RFLP technique. A total of 112 samples were collected from 14 provinces. Genomic DNA was extracted from the muscle of each individual of specimens with CTAB-Phenol: Chloroform Proteinase K method and screened appropriate primers for PCR. The PCR product of COI primers showed 710 bp in four species. These PCR products were digested with Alu I, Hha I, Hinf I and Taq I restriction enzymes and found patterns of single haplotypes as 14, 9, 8 and 7, respectively. The composite haplotypes were constructed from single haplotypes of four enzymes and showed all 55 patterns. The highest percentages of composite haplotypes patterns in C. striata, C. micropeltes,C. gachua and C. lucius were 8.38, 38.46, 50 and 100 percentages in AAAA, KFBC, LGEF and MHHA, respectively. Moreover, the composite haplotypes showed non overlapping in four species. The UPGMA dendrogram of restriction haplotype was constructed using NTSYSpc version 2.10p. The polymorphism of Alu I, Hha I, Hinf I and Taq I digested COI products were evaluated and found that the fishes were divided into 2 groups: group 1 was out group (Oxyeleotris marmorata) that separated clearly from the genus Channa,whereas group 2 consisted of all genus Channa which can be divided into 2 subgroups: subgroup 1 consisted of C. striata, C. lucius and C. micropeltes and subgroup 2 was only C. gachua. The similarity coefficient between 2 groups and subgroups of group 2 exhibited approximately 59 and 60 percentages, respectively.