Correlation and Path Analysis of Morphological Traits on Weight Traits ofRazor Clams Solen grandis and Solen strictus
KONG Yefu1,2, LI Jiandu1,2, YAN Long1,2, HONG Jingyan1,3, ZHOU Hongyu1,3, WANG Xiaolin1,2, GUO Dong1,2
1. Liaoning Ocean and Fisheries Science Research Institute, Dalian 116023, China; 2. Key Laboratory ofConservation, Exploration and Utilization of Aquatic Germplasm Resources, Ministry of Agriculture andRural Affairs, Dalian 116023, China; 3. College of Fisheries and Life Science, Dalian Ocean University, Dalian 116023, China
Abstract:To investigate the influence of morphological traits on weight traits in the razor clams Solen grandis and S. strictus, mature individuals of S. grandis (n=77) and S. strictus (n=89) were collected from the offshore area of Geligang in Panjin City, Liaoning Province, China, from May to July 2022. A total of eleven morphological traits—including shell length, shell width, shell height, umbo to anterior dorsal endpoint, shell length-to-shell width ratio, and cross-sectional area as well as four body weight traits—live body wet weight, live body dry weight, soft body wet weight, and soft body dry weight—were measured. Correlation analysis, path analysis, and multiple regression analysis were employed to systematically examine the relationships between morphological and weight traits. The results revealed that the correlation coefficients between morphological traits and weight traits reached a highly significant levels (P<0.01) for both S. grandis and S. strictus, except for umbo to anterior dorsal endpoint and shell length-to-shell width ratio. Path analysis indicated distinct differences in the key morphological traits influencing weight traits between the two species: in S. grandis, the live wet body weight was primarily directly affected by cross-sectional area and shell length-to-shell width ratio; live dry body weight was co-influenced by shell length and cross-sectional area; and soft part wet weight was jointly influenced by cross-sectional area and shell length-to-shell width ratio. In S. strictus, the live wet body weight was jointly affected by cross-sectional area and shell length; live dry body weight was influenced solely by shell height; soft part wet weight was determined only by cross-sectional area; and soft part dry weight was solely determined by shell height. The determination coefficients indicated that cross-sectional area contributed 75.3% to the live wet body weight in S. grandis, significantly higher than the 44.4% contribution in S. strictus. The shell length and cross-sectional area interaction contributed 39.9% to the total determination coefficient for live dry body weight in S. grandis. The live dry body weight of S. strictus was contributed by shell height (83.1%), and the total determination coefficient for soft part dry weight was entirely attributable to shell height alone. Furthermore, optimal multiple regression equations were established to predict weight traits from morphological traits for both S. grandis and S. strictus. The results demonstrate that core morphological traits can effectively predict weight traits in S. grandis, whereas weight traits in S. strictus may be more susceptible to non-morphological factors. The findings provide important theoretical foundations and trait selection references for the selective breeding of these two razor clam species.