中文摘要：

以核DNA ITSl（Internal Transcribed Spacer 1）序列作为分子标记，对我国稻蝗属部分物种种间相互关系进行初步探讨。对获得的7种稻蝗ITSl区序列进行同源性比较、核苷酸使用频率和变异住点统计计算，分析种间核DNA变异，并用芋蝗作为外类群构建NJ和MP分子系统进化树。实验共获得ITSl序列381bp，其中变异位点48个，占所测序列的12．6％，碱基组成分析显示AT含量低于GC含量，与mtDNA富含AT的特征明显不同；核苷酸变异位点统计结果显示，稻蝗属不同种间核苷酸替换数最高为36个，发生在小稻蝗与山稻蝗之间，变异率达11．18％；而无齿稻蝗与短翅稻蝗具有相同的ITSl区序列，彼此之间没有变异。系统发育树显示，小稻蝗和其他稻蝗之间的关系相对较远，是分化较大的种类；日本稻蝗和海南稻蝗与山稻蝗、短翅稻蝗和无齿稻蝗与中华稻蝗关系较近，分别构成一个聚类簇；但是两两种之间的聚类置信度不高，种间关系还有待进一步澄清。

英文摘要：

The molecular phylogeny of Oxya species were investigated by sequencing the ribosomal DNA （rDNA） ITS1 sequences. We obtained 381bp sequences in length for the seven Oxya species and one out- group species Gesonula punctifrons. The sequences were compared, the nucleotide frequency calculated, and the molecular phylogenetic trees were constructed by NJ and MP methods using G. punctifrons as out- group. The results showed that： （1） the sequence of ITS1 included 48 variable sites （about 12.60%） and showed higher GC content than AT, which was significantly different from mtDNA sequence with much higher AT preference;（2） the largest nucleotide variation was found between O. intricata and O. agavisa with 36 variable sites（about 11.18%）,and no mutation between O. adentata and O. brachyptera; （3） the phylogenetic trees showed that O. hainanensis, O. japonica and O. agavisa was closely clustered; O. brachyptera,O, adentata and O. chinensis have close relationship;O, intricata was obviously remote from other species. In total, the more markers and samples were necessary to further examine the relationship a- mong Oxya species.