Assessment of Genetic Diversity of the Salangid, Neosalanx taihuensis, Based on the Mitochondrial COI Gene in Different Chinese River Basins

Abstract

The salangid Neosalanx taihuensis (Salangidae) is a commercially important economical fish endemic to China and restricted to large freshwater systems with a wide-ranging distribution. This fish species has continuous distribution ranges and a long-introduced aquaculture history in Chinese basins. However, the research on its population genetic differentiation within and between basins is very limited. In this regard, 197 individuals were sampled from 11 populations in the Nenjiang River Basin (A1–A4), Songhua River Basin (B1), Yellow River Basin (C1–C2), Yangtze River Basin (D1), Lanchang River Basin (E1–E2) and Huaihe River Basin (F1). Based on the COI sequence, the N. taihuensis population’s genetic difference within and between river basins was investigated. The haplotypes and their frequency distributions were strongly skewed, with most haplotypes (n = 13) represented only in single samples each and thus restricted to a single population. The most common haplotype (H4, 67/197) was found in all individuals. The analysis of molecular variance (AMOVA) revealed a random pattern in the distribution of genetic diversity, which is inconsistent with contemporary hydrological structure. The mismatch between the distribution and neutrality tests supported the evidence of a population expansion, which occurred during the late Pleistocene (0.041–0.051 million years ago). Significant levels of genetic subdivision were detected among populations within basins rather than between the six basins. Population history dynamics showed that N. taihuensis experienced an expansion during the glacial period in the late Pleistocene. Therefore, different populations should be considered as different management units to achieve effective conservation and management purposes. These results have great significance for the evaluation and exploitation of the germplasm resources of N. taihuensis.

Analysis of the genetic structure of the introduced clearhead icefish (Protosalanx chinensis) populations in northern China

“…Compared to indigenous populations, the introduced population has lower genetic diversity; same results have been found for other commercial fish such as Neosalanx taihuensis, Cyprinus carpio , and Cichla kelberi . The lower genetic diversity in the introduced population could be attributed to the genetic bottleneck that often occurs during the introduction process, as well as the potential founder effects resulting from a small number of individuals being introduced (Fang et al, 2022; Marques et al, 2016; Zhu et al, 2023). Population historical dynamics is usually detected in nucleotide mismatch distribution maps and neutrality tests.…”

Population genetic diversity and structure of Tephritis angustipennis and Campiglossa loewiana (Diptera: Tephritidae) based on COI DNA barcodes in the three-river source region, China

“…Conversely, the haplotype of C. loewiana do not exhibit dominance over those of T. angustipennis , indicating the possibility of multiple invasion sources of C. loewiana in TRSR. In both populations, except for H1, all haplotypes are private, indicating a biologically suitable environment that minimizes interspecies gene exchange and maintain stable genetic diversity ( Fang et al 2022 , Li et al 2022 , Wang et al 2023 ). High haplotype diversity in the total populations of T. angustipennis and C. loewiana indicates high polymorphism in the mt COI gene.…”

Gap-free genome assembly of Salangid icefish Neosalanx taihuensis

“…The natural population is not only distributed in the estuary area from the Yellow and Bohai Seas to the coast of the South China Sea but also in the main streams of the Yangtze River, Huai River and Yellow River and their subsidiary lakes 5 , 6 . Among these sites, the Yangtze River basin and Taihu Lake are the core habitats of the natural population of N. taihuensis 7 – 9 . The natural N. taihuensis population size has declined seriously due to overfishing and habitat destruction 10 .…”

“…The natural N. taihuensis population size has declined seriously due to overfishing and habitat destruction 10 . Fortunately, artificial translocation activities for N. taihuensis have greatly expanded the spatial-geographic distribution and population diversity of the species 7 , 11 – 13 . Translocation activities in waters such as the Erhai Sea, Fuxian Lake, Dianchi Lake and the Three Gorges Reservoir have resulted in the formation of stable populations of N. taihuensis in these new habitats 8 , 11 , 14 , 15 .…”

“…Translocation activities in waters such as the Erhai Sea, Fuxian Lake, Dianchi Lake and the Three Gorges Reservoir have resulted in the formation of stable populations of N. taihuensis in these new habitats 8 , 11 , 14 , 15 . The study of genetic diversity between translocated and natural populations has become an interesting issue for researchers, and a variety of molecular markers, including COI, microsatellites, and Cytb, have been developed 7 , 9 , 11 , 16 , 17 . The analysis of these markers has shown that the genetic diversity of the translocated population of N. taihuensis was higher than that of the natural population and has preliminarily revealed the molecular mechanism of N. taihuensis adaptation to the environment 7 , 9 , 11 , 16 , 17 .…”