Entomopathogenic nematodes (EPNs) are widely used in biological control for soil-dwelling stages of many insect pests that are characterized by their safety to most non-target organisms and to the environment. The objectives of the present study were isolation of EPNs from agricultural soil in Egypt for further use in biological control programs and study the genetic variation among them using the molecular marker inter-simple sequence repeats (ISSR). Three out of 25 soil samples collected from fields cultivated with strawberry, tangerine, and pumpkin were positive for the presence of EPNs, using the Galleria baiting technique. Sequencing of the internal transcribed spacer (ITS) region indicated that the isolates obtained belong to Heterorhabditis sp. The ITS sequences were submitted to the National Center for Biotechnology Information (NCBI) and registered under accession nos. MH553165, MH553168, and MH553169. Six ISSR primers were used. The numbers of polymorphic bands were 42 out of 56, and the polymorphism percentage was 75%. The highest number of bands was 12 bands generated by primer ISSR8 followed by UBC-809 (11 bands) while recorded the lowest band number (4 bands), the percentage of polymorphism ranged from 40% (ISSR1) to 100% (ISSR6). ISSR marker can be considered a good marker to study genetic diversity and detecting the genetic polymorphism among the nematodes species.

中文翻译：

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分离，鉴定和研究属于Heterorhabditis sp。的三个昆虫病原线虫之间的遗传多样性。使用ISSR技术

昆虫病原线虫（EPN）广泛用于许多害虫在土壤中的生长期的生物防治，其特点是对大多数非目标生物和环境的安全性。本研究的目的是从埃及的农业土壤中分离EPNs，以进一步用于生物防治计划，并使用分子标记简单序列重复序列（ISSR）研究其中的遗传变异。使用Galleria诱饵技术，从用草莓，橘子和南瓜栽培的土壤中采集的25个土壤样品中，有3个对EPNs呈阳性反应。内部转录间隔区（ITS）区域的测序表明，获得的分离株属于异种杂种。ITS序列已提交给国家生物技术信息中心（NCBI），并以登录号注册。MH553165，MH553168和MH553169。使用了六个ISSR引物。多态性条带数为56个中的42个，多态性百分比为75％。带的最高数目是由引物ISSR8产生的12个带，其次是UBC-809（11个带），而记录的最低带数（4个带），多态性的百分比范围为40％（ISSR1）至100％（ISSR6）。ISSR标记可以被认为是研究线虫物种间遗传多样性和检测遗传多态性的良好标记。带的最高数目是由引物ISSR8产生的12个带，其次是UBC-809（11个带），而记录的最低带数（4个带），多态性的百分比范围为40％（ISSR1）至100％（ISSR6）。ISSR标记可以被认为是研究线虫物种间遗传多样性和检测遗传多态性的良好标记。带的最高数目是由引物ISSR8产生的12个带，其次是UBC-809（11个带），而记录的最低带数（4个带），多态性的百分比范围为40％（ISSR1）至100％（ISSR6）。ISSR标记可以被认为是研究线虫物种间遗传多样性和检测遗传多态性的良好标记。