皱纹盘鲍南北方群体的高温应激和生长差异

摘要

为研究皱纹盘鲍(Haliotis discus hannaiIno)经过杂交和南方养殖后,南方群体(杂交群体)是否与北方群体(自交群体)在适温性上是否产生了差异,从而是否更加适应南方高温环境,本研究开展了皱纹盘鲍南北方群体的高温应激和南方地区养殖实验.高温应激实验中:经过30℃应激后,南方群体恢复期所有取样组织中HSP70在0 h的表达量都显著高于北方群体(P<0.05),HSP90在外套膜和肝胰脏中的表达量也高于北方群体(鳃中的表达量略低但差异不显著);经过33℃应激后,南方群体HSP70和HSP90在足、外套膜和鳃0 h表达量都显著高于北方群体(P<0.05).养殖实验中:从12月开始至翌年2月水温不超过17.11℃,为北方群体的快速生长期,生长快于南方群体;从3月开始,水温逐渐超过20℃,北方群体生长慢于南方群体,同时北方群体开始出现死亡现象,7月北方群体大量死亡,存活数量不足30粒.综合HSP70、HSP90的高温应激表达和养殖实验结果,可以得出:皱纹盘鲍经过杂交和南方累代养殖后,适温上限有所提高,已与北方群体产生较大差异,可适应较高的水温;30℃水温刺激下南北方群体的HSP70的相对表达量与对高温的耐受性具有正相关性,可以在鲍的抗高温选育种中进行辅助筛选.%Hybrid abalone (Haliotis discus hannai) have been cultured in southern China for many years. Two ex-periments were performed (high temperature stress and culture in a southern sea area) to study whether a southern population (hybrid population) of Pacific abalone has different high temperature tolerance and is more adapted to that environment than a northern population (inbred population). After a 30℃ stress or in the high temperature stress experiment, relative expression of heat shock protein (HSP)70 in the southern population at 0h of the re-covery phase was significantly higher in the foot, mantle, gill, and hepatopancreas than those in the northern population (P<0.05). At the same time, relative expression of HSP90 in the southern population was significantly higher in the mantle and hepatopancreas than that in the northern population. The relative expression levels of HSP70 and HSP90 in the southern population after the 33℃ stressor were significantly higher in the foot, mantle, and hepatopancreas at 0 h in the recovery phase than those in the northern population (P<0.05). In another ex-periment, the most rapid growth period in the northern population occurred from December to February;abalone in the northern population grew faster than those in the southern population and water temperature was no higher than 17.11℃ at this time. Water temperature eventually exceeded 20℃ in March, when the northern population grew slower than the southern population and mortality increased. Less than 30 abalone in the northern population remained in July. Taken together, we conclude that because hybrid abalone have been cultured for many genera-tions in southern China, they became better adapted to higher water temperature. The relative expression levels of HSP70 in the two populations were positively correlated with heat resistance after the 30℃ stressor. These data could be useful for assisted selection in an abalone high temperature resistance breeding program.