The reniform nematode Rotylenchulus reniformis Linford and Oliveira (Tylenchida, Hoplolaimidae) is a serious pest of a number of crops worldwide. Although different reproductive types of R. reniformis populations have been reported in Japan, there is no information regarding the difference in their pathogenicity. In this study, we investigated the distribution of R. reniformis reproductive types primarily in sweet potato fields in Kyushu for a further study on their pathogenicity. Rotylenchulus reniformis was widely detected in sweet potato fields, but there were variations in its density and male frequency. DNA amplification conducted using primers designed to distinguish the male-absent type from the male-numerous type revealed that male-rare populations in Kumamoto were the male-absent type, but a population from Saito, Miyazaki, was a mixture of both types. Although R. reniformis density was high in some fields at the harvest time in Kumamoto and Saga, there was no apparent damage to sweet potato.

中文翻译：

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日本九州轮虫（Tylenchida，Hoplolaimidae）繁殖型分布

肾形线虫 Rotylenchulus reniformis Linford and Oliveira (Tylenchida, Hoplolaimidae) 是世界范围内许多作物的严重害虫。虽然日本已经报道了不同生殖类型的肾形雷管菌种群，但尚无关于其致病性差异的信息。在这项研究中，我们调查了主要在九州甘薯田中的 R. reniformis 繁殖类型的分布，以进一步研究其致病性。Rotylenchulus reniformis 在甘薯田中广泛检测到，但其密度和雄性频率存在差异。使用旨在区分雄性缺失型和雄性众多型的引物进行的 DNA 扩增显示，熊本的雄性稀有种群是雄性缺失型，但宫崎县斋藤的种群是雄性缺失型。是两种类型的混合体。尽管熊本和佐贺的收获期部分田地R. reniformis密度较高，但对甘薯没有明显危害。