三角帆蚌生长和壳色性状早期复合选择的优化研究

The Optimization of Early Compound Selection for Growth Traits and Shell Color in Hyriopsis cumingii

中文关键词: 三角帆蚌  早期选择  生长性状  壳色  选择顺序  中选率

英文关键词: Hyriopsis cumingii  Early selection  Growth trait  Shell color  Selection order  Retention rate

中文摘要:

      本研究以三角帆蚌(Hyriopsis cumingii)‘申紫1号’F1为研究对象，在幼蚌壳色透明期，根据目标性状的选择顺序和中选率，设置了7种依次选择法。壳长(SL)为第1选择性状，贝壳深紫色(PN)为第2选择性状，设定3种中选率，选择方法分别为SL 50% × PN 20% (Ⅰ)、SL 30% × PN 33%(Ⅱ)、SL 20% × PN 50%(Ⅲ)；贝壳深紫色(PN)为第1选择性状，壳长(SL)为第2选择性状，设定3种中选率，选择方法分别为PN 50% × SL 20%(Ⅳ)、PN 30% × SL 33%(Ⅴ)、PN 20% × SL 50%(Ⅵ)；另外1组经验选择法SI 10%(Ⅶ)作为对照组，选择内壳色深紫色和体型大的个体，每种方法的综合中选率均为10%。经过300 d养殖后，通过比较分析选留三角帆蚌的生长和壳色性状表现，对这7种方法的早期选择效果进行综合评价。结果显示，不同选择方法，早期选择效果不同，方法Ⅳ和方法Ⅵ选留个体的生长性状表现最佳，方法Ⅱ最差；方法Ⅰ~方法Ⅲ对于壳色的选择效果最佳，方法Ⅳ对于壳色的选择效果较差；传统选择方法选留的三角帆蚌性状表现不突出。以贝壳深紫色为第1选择性状的方法，对于生长性状的早期选择效果优于以壳长性状为第1选择性状的选择方法；以壳长性状为第1选择性状的方法，对于壳色的早期选择效果优于以贝壳深紫色为第1选择性状的选择方法，说明选择顺序对于选择效果影响显著。更加关注的目标性状，在依次选择中，最后选择效果更佳；中选率影响选择效果，但受到复合选择的影响。

英文摘要:

      At the early stage, the shell of the strain F1 of “Shenzi No.1” Hyriopsis cumingii is transparent, so the workload involved in selection and improving the breeding efficiency can be reduced at this stage. In this study, seven different selection methods were tested with different selection orders and retention rates of objective traits. When shell length (SL) was the first trait selected and a deep purple shell (PN) was the secondarily selected trait, the different methods used were SL 50% × PN 20%, SL 30% × PN 33%, and SL 20% × PN 50%. However, when the selection order was the opposite of this, the selection methods used were PN50% × SL 20%, PN 30% × SL 33%, and PN 20% × SL 50%. Moreover, according to conventional experience, juveniles with a deep purple shell and large size were selected simultaneously in a seventh control gorup. This was done to compare the experimental results of this control group with those of the other six methods. The total retention rate of each method was 10%. After five months of culture, the growth traits (shell length, shell height, shell width, body weight, mantle weight, and shell weight) and the inner shell color parameters (L, a, b, and dE) of the selected mussels were measured to evaluate the early selection effects of these seven methods. The results showed that the different selection methods led to differences in the effects of early selection. The growth traits of individuals selected by the PN 50% × SL 20% and PN 20% × SL 50% methods were the best, while the selection effect of the SL 30% × PN 33% method was the worst. However, when the deep purple shell was selected as the objective trait, the other three methods (SL 50% × PN 20%, SL 30% × PN 33% and SL 20% × PN 50%) were better than the above methods. The selection effect of the SL30% × PN 33% method was the worst for the growth traits. The traits of H. cumingii selected by the traditional method were not prominent in any of the experimental groups. The method of taking SL as the first selection trait was SL × PN, while the method of taking PN as the first selection trait was PN × SL. In the early stage, the SL × PN method can be used to select for clams with a deep purple shell color, while the PN × SL method can be used to select for larger clams. The results showed that the selection order had a significant impact on the selection effect. In addition, when the traits with higher expectations were selected at the end, the effect of the selection was better. Further more, both the retention rate and the compound selection response affected the selection effect.