光照对凡纳滨对虾幼体变态发育的影响

Effect of light on the larval metamorphosis of Litopenaeus vannamei

为了解光照对凡纳滨对虾(Litopenaeus vannamei)幼体发育和存活率的影响,作者在研究中设定了4种单色光(红、黄、蓝、绿光)及不同光照强度(0、1 500、5 500、12 000 lx)进行实验并就光照对幼体产生的影响进行分析。实验表明:4种单色光对幼体发育变态时间和成活率都有较大影响。幼体从ZⅠ变态发育至仔虾P1,蓝光的幼体发育时间最长,为262.83 h,比对照组多28 h;黄光存活率最低,只有14.49%,比对照组低25.00%,差异显著(P<0.05)。同时,凡纳滨对虾幼体在不同的发育阶段对不同光色的敏感度不同,红光和黄光只对溞状幼体变态有较明显的抑制作用,但对糠虾幼体的发育却有促进作用;蓝光和绿光对整个发育阶段都有影响。光照强度对幼体的存活和变态影响差异显著(P<0.05)。幼体从ZⅠ发育至P1,12 000 lx光照下幼体变态发育耗时最长(257.33 h),存活率最低(1.63%)。在溞状幼体期,光照大于1 500 lx时,幼体的变态时间增加,存活率下降。糠虾幼体期可适应光照在5 500 lx以下的环境,而仔虾期则可适应120 000 lx的光照。建议根据不同发育阶段调整光照强度,当幼体在ZⅠ时,光强应控制在1 500 lx以下,之后可逐渐增强。本实验结果可为凡纳滨对虾育苗期间的光照管理提供基础数据和理论依据。

In order to study the effects of light on larval development and survival of Litopenaeus vannamei, four colors of light （red, yellow, blue, and green） and four different light intensities （0, 1 500, 5 500 and 12 000 lx） were designed, and the effects were evaluated systematically. The results showed that four colors of light have great impacts on L. vannamei larval metamorphosis. Under blue light conditions, the time e span of ZⅠ （zoea I stage） larval development to P1 （postlarvae 1） was the longest （262.83 h）, 28 h longer than that of the control group. When given yellow light, the larvae exhibited a survival rate of 14.49%, which was 25.00% lower than that of the control （P 〈 0.05）. In addition, shrimp larvae at different stages demonstrated different sensitivities to colored light. Red and yellow light could inhibit larval development at their zoea stage, but could promote larval development at the mysis stage, and blue and green lights had impacts on the entire developmental stage. A significant difference （P 〈 0.05） in larval survival and metamorphosis was observed among the four light intensity gradients. Larvae in the 12 000 Lux group experienced the longest development time （257.33 h） from ZⅠ to P1 and had the lowest survival rate of 1.63%. At the zoea stage, when the light was higher than 1500 lx, the duration of larvae metamorphosis increased, while the larval survival rate decreased. Larvae at the mysis stage could develop successfully under a light intensity of 5 500 lx, and the post larvae could adapt to a light intensity of 12 000 lx. In conclusion, the light intensity should be adjusted appropriately according to the larval phase of development; it is better to maintain the light intensity lower than 1 500 lx while larvae are at the ZⅠ stage, and this index can be increased gradually over time.