Page 120 - 《水产学报》2025年第8期

林悦彤，等 水产学报, 2025, 49(8): 089310

Among the environmental conditions, fluctu- fer greater adaptability, enabling them to enhance
ations in temperature can directly alter the composi- their byssal adhesive strength and adapt to their
tion and structure of mussel byssal threads, thereby environments.
[11]
impacting both their quantity and quality . For The present study showed that the individual
example, in M. edulis, the secretion of byssal size of mussels was not the main factor influencing
threads increases with temperature, ranging from 0 the byssal adhesive strength, which might mainly
[39]
to 25℃ . Byssal attachment strength varies not result from genetic factors. This study demonstrates
only with the number of byssal threads produced that three populations inhabiting distinct thermal
but also with performance factors such as shedding environments exhibit variations in byssal thread
[26]
rate and breaking force . In M. coruscus, both the phenotypes. These differences are likely a result of
diameter and breaking force of the byssal threads environmental selective pressures, which may have
[26]
decrease as temperature rises from 21 to 31℃ . contributed to the observed phenotypic divergence.
The present study revealed that the SS population Environmental conditions across different geo-
inhabited inhabiting the lower latitude produced the graphical organisms can affect the genetic architec-
highest mean number of byssus threads, along with ture and evolutionary divergence of meta-popula-
superior mechanical properties, including byssal tions by imposing selective pressures and influen-
[42]
thread diameter, byssal breaking force and plaque cing migration patterns . Species with wide distri-
adhesion strength. Our findings suggest that the butions often inhabit heterogeneous environments,
byssal threads in SS mussels have the highest byssal leading to localized patterns of adaptive divergence
[42]
plaque adhesion and byssal strength toughness, among populations . The allele frequencies at 6
which enable them to compete effectively in their SSR loci were found to be significantly correlated
natural habitats, particularly in areas with strong with byssus phenotypes in the current study, sug-
currents or wave action. Water temperature in the gesting that environmental selection may have
East China Sea increases progressively with influenced allele frequencies across three latitud-
[40]
decreasing latitude . Consequently, the pheno- inal regions, leading to differences in byssal adhes-
typic differences in byssal threads among the three ive strength.
populations might be attributed to temperature vari- M. coruscus has a long floating time for the
ations linked to latitude, with mechanical perform- larval stage that lasts for around one month. Plank-
[26]
ance decreasing as temperature rises . tonic larvae migrate in response to ocean circula-
In the present study, significant differences in tion, playing a crucial role in facilitating gene flow
byssal thread phenotypic characteristics were within populations [43-45] . The coastal currents in the
observed among the three M. coruscus wild popula- East China Sea facilitated the larvae migration
tions, with the SS population inhabiting the lower between different geographical regions, such as
latitude secreting more byssal threads and exhibit- Jiaojiang and Fuding, which may contribute to the
ing stronger byssal breaking force and plaque adhe- gene flow between the two regions. This could
sion strength. The SS population, which possessed a explain the similar genetic backgrounds of M.
high byssal adhesive strength, also exhibited greater coruscus observed in the two populations. Water
genetic diversity compared to the other two popula- currents also create opportunities for larval
tions. Genetic diversity provides the ability to exchange in R. decussatus, leading to the observed
[28]
enable species to adapt to changing environments, homogeneity within its populations . However,
[41]
climates, and other challenges . The SS popula- planktonic dispersal may be modified or stopped by
tion exhibits the greatest genetic diversity com- imperceptible barriers such as oceanic fronts, gyres,
pared to the other two populations, which may con- upwellings, eddies, filaments, and environmental

中国水产学会主办 sponsored by China Society of Fisheries https://www.china-fishery.cn
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