本研究利用团头鲂(Megalobrama amblycephala)‘浦江1号’(♀)×翘嘴鲌(Erythroculter ilishaeformis)(♂)进行属间人工杂交,获得了遗传背景不同的杂交子代。结果显示,团头鲂‘浦江1号’(♀)×翘嘴鲌(♂)杂交子代的受精率和孵化率均很高,分别为90.0%和80.6%。鲂鲌杂交子代的体型有两种,其中,96.2%的后代为鲂鲌中间型体型(杂种A型),另外还存在3.8%的后代体型与母本团头鲂‘浦江1号’相近(杂种B型)。经Partec流式细胞仪测定得出,鲂鲌杂种A型个体DNA含量与母本、父本相同,表明其为二倍体。2个特异性微卫星位点(TTF6和TTF10)分析显示,杂种A型个体从其父母本中各获得了一套遗传物质,证实其为二倍体杂交种,鲂鲌杂种B型的带型则与母本完全一致,为雌核发育后代。土池同池生长性能分析显示,鲂鲌中间型个体的生长速度显著快于团头鲂‘浦江1号’和翘嘴鲌,表现出明显的超亲生长优势。本研究为鲂鲌杂交新品系的建立奠定了基础,另外,鲂鲌杂交自发产生雌核发育后代便于团头鲂纯系的构建。
In the present study, two groups with different genetic backgrounds were obtained by intergeneric crossing Megalobrama amblycephala (♀) x Erythroculter ilishaeformis (♂). Our results show that fertilization rate (90.0%) and hatching rate (80.6%) in the intergeneric cross group were high. Hybrid A (96.2%) and hybrid B (3.8%) were obtained. The morphological characters of hybrid A were intermediate between those of the parents, and hybrid B had the same morphological characters as the M. amblycephala female parent. Relative DNA content of the hybrids was examined by flow cytometry. The results show that hybrids A and B were diploid and had the same DNA content as their parents. Two pairs of specific loci (TTF6 and TTFIO) were screened by simple sequence repeat analysis. The results indicate that hybrid A inherited genetic material from both parents, whereas hybrid B only inherited maternal genetic material, indicating gynogenetic progeny. Hybrid A grew faster than either M. amblycephala or E. ilishaeformis, suggesting a clear growth advantage in earthen ponds. Our results provide basic data on a novel hybrid strain between Parabramis pekinensis and Erythroculter ilishaeformis. In addition, production of gynogenetic progeny can be applied to establish a pure line ofM. amblycephala.