舟山不同野生群体等边浅蛤形态性状对体质量的影响效果

为评估舟山不同野生群体等边浅蛤形态对体质量的影响，本研究随机选取浙江省舟山市两个海域沙滩不同地理群体等边浅蛤，并测量每个个体的壳长(SL)、壳高(SH)、壳宽(SW)这3个形态性状指标，以及阴干后活体重(GW)。采用通径分析等方法评估了各形态性状对重量性状的影响。本研究结果显示，两个地理群体等边浅蛤各形态性状对活体重的影响效果较为接近，且壳宽对其活体重的影响最大。两个地理群体各形态性状与活体重之间的相关系数均较大，且达到极显著水平(P＜0.01)，各形态性状对活体重的间接作用均大于直接作用。将偏回归系数显著的变量对体质量建立多元回归方程，分别为：Y=-41.313+0.505X1+0.773X2+0.723X3；Y=-23.607+0.258X1+0.432X2+0.888X3，其中Y代表体重，X1、X2、X3分别代表壳长，壳高和壳宽，两方程的回归系数均处于极显著水平。研究结果表明壳的长、高、宽是等边浅蛤选育中理想的测量指标，为等边浅蛤的苗种繁育提供理论依据。

Relationship between morphometric traits and body mass of Macridiscus multifarius in two different populations in Zhoushan

In order to find out the correlation among the quantitative characters and influencing factors of production of Macridiscus multifarius, high phenotypic traits shell length (SL), shell height (SH), shell width (SW), body mass (BM) of randomly selected different geographic groups of wild equilateral shallow clam in Zhoushan, Zhejiang Province were measured, and relationship between morphological traits and weight traits of M. multifarius was analyzed by path analysis. The results showed that the effects of morphological traits on body mass were different between the two populations, and shell height had the greatest influence on body mass in Shengsi population, while shell width was the most influential trait on body mass in Putuo population. The correlation coefficients between morphological traits and body mass of the two populations were great and with extremely significant correlation. The indirect action of morphological traits on body mass was greater than the direct action. The regression equations of variables with significant partial regression coefficients for body mass were expressed as Y=0.505X₁ + 0.773X₂ + 0.723X₃-41.313, Y =0.258X₁ + 0.432X₂ + 0.888X₃ -23.607, where Y represents body mass, X₁, X₂ and X₃ represent shell length, shell height and shell width, respectively. The regression coefficients of the two equations are extremely significant. The results showed that the shell height of Shengsi population was an ideal index to measure the body weight in the breeding of the equilateral shallow clam, while the shell width of Putuo population should be paid attention to, and this may provide a theoretical basis for the breeding of M. multifarious.