不同群体花鲈幼鱼温度耐受特征的初步研究

Characterization of Thermal Tolerance of Juvenile Lateolabrax maculatus from Different Communities

为研究不同驯化温度下2个群体(北方群体N、南方群体S)花鲈(Lateolabrax maculatus)幼鱼的热耐受特征,本实验设置了3组驯化温度(15、20和25℃),采用临界温度法对花鲈幼鱼(N:(6.42±0.31)g,S:(6.02±0.31)g)进行温度耐受性研究。研究表明,在3组驯化温度下(15、20和25℃)花鲈幼鱼最大临界温度(CTmax)/和最小临界温度(CTmin)/℃分别为N:37.09、37.89、38.53℃和0.93、2.83、5.23℃;S:37.10、37.63、38.03℃和1.18、3.27、6.00℃。在3组驯化温度条件下,温度耐受幅N>S,在15℃驯化条件下,N、S花鲈幼鱼温度耐受幅最大,分别为36.16和35.91℃;在15~25℃范围内,N、S的高温驯化反应率分别为0.144、0.093、低温驯化反应率分别为0.430、0.482;N、S花鲈幼鱼的热耐受区域面积分别为348.950和341.675℃~2。实验结果表明,南北方花鲈幼鱼群体的最大临界温度和最小临界温度都与驯化温度呈明显的正相关关系;在相同的驯化温度下,北方幼鱼和南方幼鱼最大临界温度无显著差异,北方幼鱼的最小临界温度明显低于南方幼鱼,且驯化温度明显影响花鲈幼鱼的温度耐受性。

This study was carried out,aiming to investigate the thermal tolerance of Lateolabrax maculatus juveniles from two geographical populations(North/N,South/S)under different acclimation temperatures.The critical temperature method was performed and three domesticated temperatures(15℃,20℃,25℃)were settled,respectively.Juvenile L.maculatus(N:6.42±0.31)g,S:(6.02±0.31)g were used to study the thermal tolerance.Results showed that under each acclimation temperatures(15℃,20℃,25℃),the maximum critical temperature(CTmax)and the minimum critical temperature(CTmin)of L.maculatus juveniles were 37.09℃,37.89℃,38.23℃and 0.93℃,2.83℃,5.23℃for N population;and 37.10℃,37.63℃,38.03℃and 1.18℃,3.27℃,6.00℃for S population,respectively.At each acclimation temperatures,the thermal tolerance amplitude of N population was higher than the thermal tolerance amplitude of S population.At the domestication temperature of 15℃,the maximum temperature tolerance of northern and southern juveniles was 36.16℃and 35.91℃,respectively.At the domestication temperatures between 15 and 25℃,the CTmax of N population and S population was 0.144 and 0.093,respectively,and the CTmin of N population and S population was 0.430 and 0.482,respectively.The thermal tolerance polygons of northern and southern L.maculatus juveniles was 348.950℃^2 and 341.675℃^2,respectively.Our results showed that the CTmax of the two populations increased significantly with the increasing of acclimation temperature,and the CTmin decreased significantly with the decreasing of domestication temperature.At the same acclimation temperature,there was no significant difference between the CTmax of northern and southern L.maculatus juvenile,but the CTmin of northern population was significantly lower than that of southern population(P<0.05),and the thermal tolerance of L.maculatus juvenile was significantly affected by acclimation temperature.