Page 96 - 《水产学报》2026年第01期

1 期 薛凌展，等：两个地理群体马口鱼形态学比较及完全双列杂交子代胚胎发育与生长 50 卷

Abstract: Opsariichthys uncirostris is a small, omnivorous freshwater fish with slightly predatory behavior. It has diverged
into two subspecies, O. uncirostris amurensis (northern China) and O. uncirostris bidens (southern China), with distinct
physiological adaptations to their respective northern and southern geographic climates. O. uncirostris amurensis is character-
ized by a shorter maturation cycle (precocious maturity), whereas O. uncirostris bidens exhibits faster growth rates. With the
growing consumer demand for stream fish, aquaculture production has intensified. However, this has led to increased inbreed-
ing, resulting in declining seed quality and disease resistance, which has impeded sustainable industry development. To address
this issue, there is an urgent need to develop new strains with superior traits. This study aimed to conduct a comparative mor-
phological analysis of these two subspecies and perform a diallel cross to evaluate heterosis in embryonic development, larval
viability, and growth performance. The ultimate goal was to produce a novel hybrid strain that outperforms both parental lines,
providing a genetically improved stock to support the high-quality development of the industry. In this study, we measured
morphological trait indices of O. uncirostris bidens (Minjiang River Population) and O. uncirostris amurensis (Songhua River
Population). Through path and correlation analyses, the influence of each trait on body weight, and the embryonic development
and growth of the offspring of the complete diallel crossing between two populations were evaluated and analyzed. Morpholo-
gical quantifiable trait analysis showed that the morphological differences between different genders in the two populations of
O. uncirostris amurensis and O. uncirostris bidens were mainly concentrated in aspects such as the overall contour of the fish
body, head shape, and fish body size. Among them, the TRL/BL standardized index of female O. uncirostris amurensis was the
largest (0.47 ± 0.02). The PFL/BL standardized index of male O. uncirostris bidens was the largest (0.18 ± 0.01). Stepwise dis-
criminant analysis identified 10 significant traits, leading to a discriminant equation with an overall accuracy rate of 98.33% to
distinguish the two populations (F = 38.881 X 1 - 53.252 X 2 - 59.503 X 3 - 7.545X 4 + 22.466 X 5 + 22.387X 6 - 20.866 X 7 - 0.306 X 8
+ 0.228 X 9 + 0.376 X 10 - 6.082). Correlation analysis showed that the 17 growth traits of the two groups were positively correl-
ated with body weight. Path analysis showed that the correlation coefficient between body weight and body thickness was the
largest (0.93). In O. uncirostris amurensis, the correlation coefficient between total length and body weight was the largest
(0.92). Embryonic development times for offspring from shortest to longest were as follows: self-crossed progeny of O.
uncirostris bidens (SS, 37 h 28 min), progeny of O. uncirostris bidens male × O. uncirostris amurensis female (SN, 38 h 6
min), progeny of O. uncirostris amurensis male × O. uncirostris bidens female (NS, 40 h 57 min), and self-crossed progeny of
O. uncirostris amurensis (SS, 42 h 8 min). Analysis of the growth differences and mid-parent heterosis of the complete diallel
crossing progeny showed the progeny of NS group hybrids exhibited heterosis in body weight and total length at 30, 60, and 90
days after hatching, with superior parent heterosis observed at 30 and 60 days after hatching. The SN group hybrid progeny
showed mid-parent heterosis for body weight at 90 days after hatching. The study demonstrated the hybridization between the
Minjiang River population of O. uncirostris bidens and the Songhua River population of O. uncirostris amurensis has certain
heterosis, providing a valuable reference for new breed development.
Key words: Opsariichthys uncirostris; geographical populations; morphology; heterosis; path analysis
Corresponding author: DONG Zaijie. E-mail: dongzj@ffrc.cn

Funding projects: Fujian Provincial Seed Industry Innovation and Industrialization Engineering Project (2021FJSCZY04);
Basic Research Special Fund for Provincial Public Scientific Research Institutes, Fujian Provincial Department of Science and
Technology (2021R1014004, 2022R1014004, 2025R1014002); Fujian Provincial Special Fund for Marine Services and High-
quality Fisheries Development (FJHY-YYKJ-2022-2-9)

中国水产学会主办 sponsored by China Society of Fisheries https://www.china-fishery.cn
15