尼罗罗非鱼与萨罗罗非鱼正反交鱼自繁后代F2耐盐性、生长性能及亲本对杂种优势贡献力的评估  

Evaluation of growth,salt tolerance and parents' heterosis contribution in reciprocal hybrids F_2 between Oreochromis niloticus and Sarotherodon melanotheron

作　　者：李思发[1] 颜标[1] 蔡完其[1] 李腾云[1] 荚金华 张艳红 

机构地区：[1]上海水产大学农业部水产种质资源与养殖生态重点开放实验室,上海200090 [2]河北中捷农场水产良种场,河北沧州061108

出　　处：《水产学报》2008年第3期335-341,共7页Journal of Fisheries of China

基　　金：国家科技支撑计划专题[耐盐罗非鱼新品种选育(2006BAD01A1203)]

摘　　要：为选育耐盐和生长兼优的罗非鱼，以原始亲本尼罗罗非鱼（Oreochromis niloticus）和萨罗罗非鱼（Sarotherodon melanotheron）为对照，正交鱼（尼罗罗非鱼♀×萨罗罗非鱼♂）自繁第二代（F2）和反交鱼（萨罗罗非鱼♀×尼罗罗非鱼♂）自繁第二代（F2）为试验对象，观察和比较他们在盐度为0、15、20及25时的耐盐性和生长性能，并估算杂种优势及亲本的贡献力。结果如下：（1）盐度20-25是正、反交鱼的适宜生长盐度，他们在这一盐度范围里的日均增重率为尼罗罗非鱼在盐度0下的75％左右、萨罗罗非鱼在盐度25下的4倍左右，表明杂交后代的生长速度比较接近尼罗罗非鱼，远优于萨罗罗非鱼。在盐度25下，正交鱼比反交鱼生长快7％左右。（2）在盐度15与20下，生长速度和体重变异系数的杂种优势较明显，未发现不同盐度会导致正反交鱼成活率有显著变化。（3）不同亲本鱼类的强势性状，如尼罗罗非鱼的快速生长、萨罗罗非鱼的高耐盐性，对杂交后代的不同性状在不同盐度中有不同的贡献力。运用F1≤a1P1＋a2P2所作的估算表明，对杂交后代在15-25盐度下的生长率，尼罗罗非鱼的杂种优势贡献力比萨罗罗非鱼的大3～4倍；对杂交后代在25盐度下的耐盐性，尼罗罗非鱼的贡献力几乎为零，而萨罗罗非鱼的贡献力几乎为100％。In order to select a good breed both with ideal culture performance and high salt tolerance, taking Nile tilapia （Oreochromis niloticus） and black-chip tilapia （Sarotherodon melanotheron） as control groups, two reciprocal hybrids, i.e., O. n. ♀× S. m. ♂ （F2） and S. m. ♀× O. n. ♂ （F2） as trial groups, comparisons were conducted under 4 salinities （0, 15, 20 and 25 ）. The major results were： （1） Both O. n. ♀×S. m. ♂ （F2） and S. m. ♀×O. n. ♂ （F2） showed a better growth under salinities 20 and 25 , equal to about 75% of growth of Nile tilapia under salinity 0 ,and 4 times of growth of black-chip tilapia, under salinity 25. It indicated that the growth of hybrids close to O. n., but much better than black-chip tilapia. Under 25 salinity, O. n. ♀× S. m. ♂ （F2） showed 7% faster growth than S. m. ♀× O. n. ♂ （F2）. （2） Under 15 and 20 salinity, the heterosis showed higher in growth rate and coefficient variation of body weight, and it was found that salinities 0,15,20,25 could not cause a significant difference in survival of two hybrids. （3）It is found that, the superior traits from different parent fish species, such as the fast growth of Nile tilapia, and the high salt tolerance of black-chip tilapia, are of different contribution for different traits of hybrids under different salinities. Estimated by the formula F1 ≤a1P1 ＋ a2P2, the contribution for growth of hybrids from Nile tilapia is 3- 4 times higher than that from black-chip tilapia at salinity 15 - 25, and the contribution for survival of hybrids in 25 salinity is almost 0 from Nile tilapia, but 100% from black-chip tilapia.

关 键 词：尼罗罗非鱼 萨罗罗非鱼 正反交 生长 耐盐性 杂种优势贡献力 

分 类 号：S917[农业科学—水产科学]