中国东亚飞蝗四个地理种群遗传结构的比较研究

利用水平切片淀粉凝胶电泳技术，分析了不同蝗区东亚飞蝗四个地理种群的遗传结构。在检测的20个酶基因座位中，四个种群均表现出一定的遗传多态性， 多态位点的百分率普遍偏高 (P=70%～80%),但由于杂合子数目较少而使每个位点的平均杂合度观察值偏低(H_o=0.023～0.032)。对每个基因座位的各基因型进行χ²检验， 除 Adk-1、Gdh-1、G3pd-1和Pgm-1在部分种群符合Hardy-Weinberg平衡外，其余绝大多数基因座位的基因型频率显著偏离Hardy-Weinberg平衡。从F统计量看，四个种群之间的遗传分化较低(F_st=0.0606 )。它表明： 东亚飞蝗较强的长距离迁飞行为增加了种群之间的基因交流， 降低了种群之间的遗传分化。根据Nei的遗传一致度（I）和Roger的遗传距离（D）进行分析， 在山西临猗与山西永济(I=0.964, D=0.175)、河南中牟与江苏沛县种群(I=0.957, D=0.160)之间，呈现出较高的遗传一致度和较小的遗传距离。结果表明： 迁飞性蝗虫东亚飞蝗种群之间的遗传分化与地理距离呈正相关。

Genetic structure of four geographic populations of Locusta migratoria manilensis in China

The genetic structure of the four geographic populations of the Oriental migratory locust Locusta migratoria manilensis was analyzed using horizontal starch gel electrophoresis. Among 20 loci of 13 isozymes identified, the higher the percentage of polymorphic loci ( P = 70% - 80% ), the lower the observed overall heterozygosity ( Ho = 0.023 - 0.032). The result from Chi-square test for the genotype frequencies showed the genotype frequency at most loci deviated significantly from HardyWeinberg equilibrium except Adk- 1, Gdh- 1, G3pd- 1 and Pgm- 1. Based on F-statistics ( average Fst = 0.0606), an extremely small genetic differentiation among the four populations was observed. It appeared that the long-distance migration of the locust enhanced gene flow and decreased genetic differentiation. The divergence among four populations was revealed using Nei's genetic identity (I) and Roger's genetic distance (D). The higher the genetic identity, the smaller the genetic distance observed between Shanxi-Linyi and Shanxi-Yongji populations (I = 0.964, D = 0.175), and between Jiangsu-Peixian and Henan-Zhongmou populations ( I = 0.957, D = 0. 160). The results indicated that there was a positive relationship between genetic differentiation and geographic distance.