宽翅曲背蝗两个地理种群等位酶的比较

采用水平淀粉凝胶电泳技术及应用等位酶分析方法，研究我国河北黄骅、辽宁葫芦岛宽翅曲背蝗两个自然种群的遗传多样性和遗传分化。在检测的11种酶15个酶基因座位中，Adk-I、Fbp-I、Mdh-2和G3pd-I基因座位的等位基因少，而Fbp-2、Mdh-I和Me-I基因座位的等位基因多。对每个基因座位的各基因型进行χ^2检验，除Mdh-I在辽宁葫芦岛种群、Adk-I在河北黄骅种群分别符合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。两个种群之间存在明显的遗传多样性和分化：多态位点百分率分别为100％和93．3％，等位基因平均数分别为3．1和2．5，平均杂合度观测值分别为0．086和0．061。与其他非迁飞性蝗虫如中华稻蝗(Oxya chinensis)比较，这种蝗虫种群的平均杂合度较低但遗传多态性较高。结果表明：该蝗虫较强的跳跃能力可使个体暴露于各种不同环境，有利于维持种内遗传多态性的动态平衡，而种群保持较高的遗传多态性能增强该物种在不同栖息地的生存和繁殖能力。F-统计量表明两个种群之间的遗传分化相对较小，但这种分化显著高于迁飞性蝗虫如东亚飞蝗(Locusta migratoria manilensis)。Nei的遗传一致度(I)和Roger的遗传距离(D)的结果分析揭示了两个种群之间较高的遗传一致度(I=0．904)和较小的遗传距离(D=0．256)。然而，在一些酶基因座位如Aep-I(Fst=0．462)和Pgi-I(Fst=0．182)，F-统计值相对较大，遗传分化比较明显。

Comparative Allozyme Analysis of Two Geographic Populations of Pararcyptera microptera meridionalis in China

The genetic structure of the two populations of Pararcyptera microptera meridionalis (Ikonn.) from Hebei and Liaoning in China was analyzed with horizontal starch gel electrophoresis.Among 15 loci of 11 enzymes identified in zymograms,Adk-1,Fbp-1,Mdh-2 and G3pd-1 showed low variability with few alleles.Higher allelic polymorphisms were observed at Fbp-2,Mdh-1 and Me-1.The two populations demonstrated high percentage of polymorphic loci (93.3% and 100.0%) but low observable overall heterozygosity (0.061 and 0.086),that could be attributed to heterozygote deficiencies,which led to the genotype frequency deviating from Hardy-Weinberg expectations.It is reasoned that the strong movement capability of the insect makes the individuals likely to be exposed to drastically varied environments,which tends to maintain dynamic equilibrium of genetic polymorphisms.The F-statistics between the two populations was comparatively smaller (F_(st)=0.084),but larger when compared with those in migratory locusts like Locusta migratoria manilensis.Nei's genetic identity (I) and Roger's genetic distance (D) also showed close genetic relationship of the two populations by their high genetic identity (I=0.904) and small genetic distance (D=0.256).However,considerably qualitative and quantitative differences were noted at loci Acp-1(F_(st)=0.462) and Pgi-1 (F_(st)=0.182).