大黄鱼(♀)×鮸鱼(♂)杂交F_1和大黄鱼初孵仔鱼盐度适应性的比较研究

Comparison of salinity tolerance of newly hatched larvae of Pseudosciaena crocea and hybrid F_1 of Pseudosciaena crocea (♀) ×Miichthys miiuy (♂)

比较了盐度对大黄鱼Pseudosciaena crocea(♀)×大黄鱼(♂)自交F1和大黄鱼(♀)×鮸鱼Miichthys miiuy(♂)杂交F1初孵仔鱼存活的影响。将大黄鱼和杂交F1初孵仔鱼从盐度27的海水中分别转移至盐度12、17、22、27、32、37和42的海水中。结果表明,大黄鱼和杂交F1初孵仔鱼的存活率、平均存活时间(MST)、不投饵存活系数(SAI)随着盐度的升高呈下降趋势。在盐度12～32范围内,杂交F1初孵仔鱼的SAI值高达62.42～86.56,明显比大黄鱼初孵仔鱼高(46.18～53.89)。在盐度12条件下,大黄鱼和杂交F1初孵仔鱼的MST达到最大值,分别为(10.69±0.16)d和(13.47±0.35)d;盐度42时,MST降至最低(4.91±0.27)d和(6.30±0.27)d。相同盐度下,对大黄鱼和杂交F1初孵仔鱼的存活率下降趋势、半数死亡时间(DT50)、平均存活时间(MST)和不投饵存活系数(SAI)的分析显示,杂交F1初孵仔鱼具有更好的存活能力,表现出较强的杂种优势。

The effects of salinity on the survivial of newly hatched larvae of Pseudosciaena crocea and the hybrid F, of Pseudosciaena crocea （♀）× Miichthys miiuy （ ♂ ） were investigated. The newly hatched larvae were transferred from sea water （salinity 27） to other seven salinities （12, 17, 22, 27, 32, 37, 42）. The results showed that the survival rate, mean survival time （MST） and survival activial index （SAI） of the newly hatched larvae of large yellow croaker and hybrid F1 are decreased following the increase of salinity. In the salinity range of 12 to 32, the SAI values of hybrid F1 was up to 62.42 to 86.56 which was significantly higher than the large yellow croaker （46.18 to 53.89）. At the salinity 12, the MST of large yellow croaker and hybrid F1 reached the maximum value, （ 10.69±0.16） d and （ 13.47 ±0.35 ） d , and at the salinity 42, the MST reached a minimum value, （4.91±0.27） d and （6.30±0.27） d. The continued downward trend of survival rate, median death time （DT50）, mean survival time （MST） and survival activial index （SAI） of the newly hatched larvae of large yellow croaker and hybrid F1 were compared at the same salinity. The results show that the newly hatched larvae of hybrid F1 had stronger ability to survive during salinity changes, and showed strong heterosis.