魁蚶中国群体与韩国群体杂交子一代养成期生长比较

Growth of a first-generation hybrid between Chinese and Korean populations of Scapharca broughtonii during the adult culture stage

中文关键词: 魁蚶  杂交  养成期  壳长  湿重  杂种优势

英文关键词: Scapharca broughtonii  Hybridization  Adult culture stage  Shell length  Wet weight  Heterosis

中文摘要:

      以魁蚶(Scapharca broughtonii)中国群体(C)和韩国群体(K)为材料，进行了4个组合的杂交和自交实验，测定了各实验组魁蚶在养成期(10~15 月龄)的壳长、湿重，并计算了杂交组合的杂种优势。结果显示，养成期杂交KC组壳长显著高于自交CC组、KK组和杂交CK组，CK组壳长杂种优势率在–2.03%~5.44%之间，KC组壳长杂种优势率在4.40%~14.74%之间，且KC组壳长杂种优势率始终高于CK组；养成期杂交KC组湿重始终显著高于自交CC、KK组和杂交CK组，而杂交CK组仅在14、15月龄显著高于自交CC和KK组，2个杂交组合湿重的杂种优势率始终为正值，CK组湿重杂种优势率在1.41%~7.71%之间，KC组壳长杂种优势率在5.32%~23.71%之间，且KC组湿重的杂种优势率始终高于CK组，在湿重性状方面杂种优势更明显。综合分析表明，杂交KC组的杂交子一代在壳长和湿重方面的杂种优势更加明显，是理想的育种材料。

英文摘要:

      Scapharca broughtonii (Mollusca, Bivalve, Arcoida), one of the most important commercial marine bivalve species, is mainly distributed on the coasts of the Bohai Sea, and north of the Yellow Sea, China. With the deterioration of marine ecological environments resulting from the extended farming scale and frequency of human activities in coastal waters, and over-fishing, wild resources have decreased. Mass mortality has become a major constraint for the development of S. broughtonii culture. The hybridization of different populations has proven to be a good breeding method. Intraspecific hybridization was investigated using two stocks of S. broughtonii; the China population (C) and the Korea population (K). The shell length and wet weight were compared between two reciprocal hybrid crosses (C♀ × K♂, CK and K♀ × C♂, KC) and two parental groups (C♀ × C♂, CC and K♀ × K♂, KK) during the adult culture stage. The results showed that the shell length and wet weight of the KC group were significantly higher than those of the other three groups. The heterosis rates of the CK group for shell length was between –2.03% and 5.44%, and the KC group was between 4.40% and 14.74%. The heterosis rates of the CK group for wet weight was between 1.41% and 7.71%, and the KC group was between 5.32% and 23.71%. The heterosis rates of the KC group for shell length and wet weight was higher than those of CK group. The wet weight of the CK group was significantly higher than that of the CC and KK groups at 14 and 15 months, respectively. Additionally, the heterosis rate of the two reciprocal hybrid crosses for wet weight was positive and high. In summary, the heterosis rates of the KC group for shell length and wet weight were markedly higher than those of other three groups, thus, the KC hybrid group could be selected as an ideal breeding material.