3个凡纳滨对虾引进群体对温度和盐度耐受力的配合力分析

Analysis of combining ability of survival of imported Litopenaeus vannamei populations under temperature and salinity stress

为筛选凡纳滨对虾（Litopenaeus vannamei）人工选育亲本的最佳组合方式,作者采用完全双列杂交交配设计,对3个凡纳滨对虾引进群体建立了9个自繁和杂交组合群体,研究了亲本和子代对温度和盐度的耐受力。研究结果表明：9个群体对温度、盐度胁迫的耐受性均存在显著差异（P〈0.05）,耐高温性状中亲优势（MP）和超亲优势（BP）的变化范围是–17.71%-52.95%和–30.07%-37.96%,其中UM和UH群体的杂交中亲优势均值最高,达到38.61%;耐低温性状MP和BP的变化范围是–22.04%-77.03%和–33.93%-31.17%,其中UM和TZ群体的杂交中亲优势均值最高,为60.85%;耐高盐性状MP和BP的变化范围是–39.41%-76.96%和–42.12%-19.07%,其中UM和TZ群体的杂交中亲优势均值最高;耐低盐性状MP和BP的变化范围是–44.89%-37.05%和–45.68%-28.21%,而UM和TZ群体的杂交中亲优势均值最低,仅为–9.855%;杂交后代耐受性的表现受到父本、母本一般配合力以及杂交组合特殊配合力共同影响,其中UM群体耐高低温性状的一般配合力较高,而TZ群体耐高低盐性状的一般配合力较高;特殊配合力分析表明,UM×UH为强优势组合,存在较强的抗逆非加性效应,杂交优势明显。本研究从数量遗传水平评估选育群体对温盐的耐受性能,可为进一步家系选育提供候选材料。

To select the optimal combination of parents for artificial breeding, three introduced populations of Litopenaeus vannamei were used to establish nine inbred and hybridized populations by complete diallel crosses, and their temperature and salinity tolerance were compared. Significant differences in temperature and salinity tolerance were observed among the nine populations. Mid-parent heterosis and heterobeltiosis for tolerance to high temperature were –17.71%–52.95% and –30.07%–37.96%, respectively, in which the UM and UH groups had the highest mid-parent heterosis（38.61%）. Mid-parent heterosis and heterobeltiosis for tolerance to low temperature were –22.04%–77.03% and –33.93%–31.17%, respectively, in which the UM and TZ groups had the highest mid-parent heterosis（60.85%）. Mid-parent heterosis and heterobeltiosis for tolerance to high salinity were –39.41%–76.96% and –42.12%–19.07%, respectively, in which the UM and TZ groups had the highest mid-parent heterosis（60.85%）. Mid-parent heterosis and heterobeltiosis for tolerance to low salinity were –44.89%–37.05% and –45.68%–28.21%, respectively, in which the UM and TZ group had the lowest mid-parent heterosis（–9.855%）. The general combining ability of parents and special combining ability of hybrid combinations influenced the tolerance performance of the hybrid offsprings; of these, the UM group had the highest general combining ability for resistance traits of high and low temperature, while the TZ group had the highest general combining ability for resistance traits of high and low salinity. The specific combining ability analysis showed that UM×UH, with a stronger, non-additive effect and hybrid superiority, was a strong hybrid combination and could be used as a candidate material for further family selection.