设计特异性引物对线粒体COⅠ基因及核基因（enc1、ptr和sh3px3）进行群体扩增，通过DNASTAR 7.1的Megalign程序对所有样本的COⅠ基因序列进行同源性比对分析，以确定罗非鱼样本的母本;采用MEGA 6.0对enc1、ptr和sh3px3基因进行序列比对和校正，并构建各采样点罗非鱼样本的系统发育进化树。【结果】广西右江流域5个采样点的罗非鱼母本种类共有4种，分别为尼罗罗非鱼（Oreochromis niloticus）、齐氏罗非鱼（Coptodon zillii）、莫桑比克罗非鱼（O. mossambicus）和奥利亚罗非鱼（O. aureus）。在26尾隆安罗非鱼样本中无杂合个体;在36尾平果罗非鱼样本中有3个杂合个体，杂合率为8.3%;在20尾田东罗非鱼样本中有2个杂合个体，杂合率为10.0%;在30尾田阳罗非鱼样本中有2个杂合个体，杂合率为6.7%;在24尾百色罗非鱼样本中有4个杂合个体，杂合率为16.7%。【结论】广西右江流域野生罗非鱼的种间杂交率并不高，但其杂交优势更有利于罗非鱼种群的扩散，进一步侵占土著鱼种的生存空间，严重威胁广西右江流域鱼类资源的多样性，有关部门应加强监管力度以防止野生罗非鱼种群迅速扩散。
关键词： 罗非鱼;DNA条形码;杂合性;广西右江流域
中图分类号： S965.125 文献标志码： A 文章编号：2095-1191（2019）12-2797-09
Wild tilapia population and its hybridization in
Youjiang River， Guangxi
ZHENG Xiong1， ZHAO Li-chao2， WU Zhi-qiang1，3*， ZHANG Jie4，
HUANG Liang-liang1，5， WANG Kai-cheng2， ZHANG Man2
（1College of Environmental Science and Engineering， Guilin University of Technology， Guilin， Guangxi 541006， China; 2College of Animal Science and Technology， Guangxi University，Nanning 530004， China; 3Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Area， Guilin University of Technology， Guilin， Guangxi 541004， China; 4Institute of Zoology， Chinese Academy of Sciences， Beijing 100101， China; 5Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology， Guilin， Guangxi 541004， China）
Abstract：【Objective】Researching species and heterozygosity among the population of wild tilapias in Youjiang Ri-ver basin of Guangxi to provide scientific base for prevention of tilapia invasion and conservation of indigenous species.【Method】A total of 136 tilapia individuals from Long’an， Pingguo， Tiandong， Tianyang and Baise in Youjiang River basin were studied. The DNA extraction， PCR amplification and gene sequencing based on COⅠ from mitochondria，and enc1，ptr， sh3px3 from ribosome with specific primers for each individual were performed. Through the megalign program of DNASTAR 7.1， the homologies of COⅠ gene sequences of all samples were compared and analyzed to determine the female parents of tilapia samples. The sequences of enc1，ptr，sh3px3 gene were compared and corrected by MEGA 6.0， and the phylogenetic trees of all samples were constructed. 【Result】The results showed that there were four female parents species in the five sampling sites， they were Oreochromis niloticus， Coptodon zillii， O. mossambicus and O. aureus. The hybrid rates of samples in Longan（26 individuals， 0 hybrid individual）， Pingguo（36 individuals， 3 hybrid individuals）， Tiandong（20 individuals， 2 hybrid individuals）， Tianyang（30 individuals， 2 hybrid individuals） and Baise（24 individuals， 4 hybrid individuals） were respectively 0， 8.3%， 10.0%， 6.7% and 16.7%. 【Conclusion】Although the interspecific hybridization rate is not too high， the situation will be more conducive to the spread of wild tilapia population and further encroachment on the living space of indigenous species，and severely threaten diversity of local fishery resources in Youjiang River basin due to heterosis. The government department concerned ought to enhance supervision，and prevent further proliferation of population of wild tilapia.