大口黑鲈(♀)×蓝鳃太阳鱼(♂)杂交F1的形态及遗传特征  

Morphological and genetic characteristics of hybrid F1 derived from largemouth bass(Micropterus salmoides)(♀)×bluegill(Lepomis mearchirus)(♂)

作　　者：李武辉 胡婕 孙成飞[1] 董浚健 田园园[1] 赵金良[2] 叶星[1,2] LI Wuhui;HU Jie;SUN Chengfei;DONG Junjian;TIAN Yuanyuan;ZHAO Jinliang;YE Xing(Key Laboratory of Tropical&Subtropical Fisheries Resource Application and Cultivation,Ministry of Agriculture and Rural Affairs,Pearl River Fisheries Institute,Chinese Academy of Fishery Sciences,Guangzhou 510380,China;College of Fisheries and Life Science,Shanghai Ocean University,Shanghai 201306,China)

机构地区：[1]中国水产科学研究院珠江水产研究所,农业农村部热带亚热带水产资源利用与养殖重点实验室,广东广州510380 [2]上海海洋大学水产与生命学院,上海201306

出　　处：《水产学报》2020年第8期1225-1236,共12页Journal of Fisheries of China

基　　金：现代农业产业技术体系建设专项(CARS-46);广东省公益研究与能力建设专项(2017A030303002);广州市科技计划创新环境建设计划珠江科技新星专题(201906010025)。

摘　　要：为探究大口黑鲈远缘杂交育种的可能性,本研究采用人工授精的方法,以大口黑鲈为母本、蓝鳃太阳鱼为父本,进行了远缘杂交实验,成功获得了杂交F1群体。大口黑鲈(♀)×蓝鳃太阳鱼(♂)杂交F1的胚胎具有正常的发育时序,在平均水温(22.5±0.5)°C条件下,胚胎发育历时约49 h,受精率约为65%,孵化率约为21%。室内养殖10周,结果显示杂交F1日均增重1.55 g,饲料利用率为0.75,杂交F1与大口黑鲈(日均增重1.56 g)具有相似的生长速率,且显著高于父本蓝鳃太阳鱼(日均增重1.07 g)。杂交F1的形态特征表现出明显的杂交属性,可数性状(侧线鳞数、背鳍、胸鳍和臀鳍数)和测量性状(可量性状和框架测量性状)均介于双亲本之间;测量性状比少数偏向于大口黑鲈,多数偏向于蓝鳃太阳鱼,且部分性状比超越了双亲本。5S rDNA基因扩增和分析显示,亲本大口黑鲈和蓝鳃太阳鱼各有2种类型的5S rDNA,杂交F1继承了双亲本4种类型的5S rDNA;4种类型的5S rDNA编码区序列(CDS,120 bp)高度保守;杂交F1与大口黑鲈的2种5S rDNA类型的转录间隔区(NTS)均包含1个“GCT”可变区(序列长度186~205 bp),而杂交F1与蓝鳃太阳鱼的2种5S rDNA类型的NTS则高度保守(序列长度分别为86和263 bp)。5S rDNA分析结果证实了杂交F1融合了双亲本的基因组。本研究为大口黑鲈远缘杂交育种的开展奠定了基础。In the present study,in order to explore the possibility of distant hybridization of Micropterus salmoides,artificial insemination was used and hybrid F1 was successfully obtained from distant hybridization between female largemouth bass and male Lepomis mearchirus.The hybrid F1 embryos underwent apparently normal morphological development.The hatching time of hybrid F1 was about 49 h when the water temperature was(22.5±0.5)°C.The fertilization rate was 65%and the hatching rate was 21%.In hybrid F1,the average weight gain was 1.55 g/d,and the fodder utilization rate was 1.24 after a ten-week in-door cultivation.The hybrid F1 showed a similar growth rate with maternal parent M.salmoides but statistically significantly higher than paternal L.mearchirus.The morphological characteristics of hybrid F1 showed obvious hybridization properties.The number traits(numbers of lateral line scales,dorsal fins,pectoral fins and anal fins)and metric traits(measurable traits and frame metric traits)in hybrid F1 showed an intermediate level between the two parents.A number of metric traits biased towards paternal L.mearchirus more than maternal M.salmoides was observed in hybrid F1.In addition,several morphology traits of hybrid F1 exceeded both of the two parents.5S rDNA gene amplification and analysis showed that the two parents possess two different types of 5S rDNA,respectively,while the hybrid F1 inherits four types of 5S rDNA from parents.The four types of 5S rDNA coding region sequences(CDS,120 bp)are highly conserved.Two types of 5S rDNA transcribed spacer(NTS)from hybrid F1 and maternal parent M.salmoides had a base"GTC"variable region(sequence length ranged from 186 to 205 bp),while two types of 5S rDNA NTS from hybrid F1 and paternal parent L.mearchirus are highly conserved(sequence length was 86 and 263 bp,respectively).These 5S rDNA types confirmed that the hybrid F1 fused genomes of the two parents.Our study provides a new perspective in exploring distant hybridization of M.salmoides.

关 键 词：大口黑鲈 蓝鳃太阳鱼 远缘杂交 形态特征 生长 5S rDNA 

分 类 号：Q321[生物学—遗传学] S965[农业科学—水产养殖]