与阿曼茄子扫帚病相关的16SrII组植原体的首次报道

First Report of a Group 16SrII Phytoplasma Associated with Witches'-Broom of Eggplant in Oman.

作者信息

Al-Subhi A M, Al-Saady N A, Khan A J, Deadman M L

机构信息

Department of Crop Sciences, Sultan Qaboos University, P.O. Box 34, Al Khod 123, Sultanate of Oman.

出版信息

Plant Dis. 2011 Mar;95(3):360. doi: 10.1094/PDIS-10-10-0761.

DOI:10.1094/PDIS-10-10-0761

PMID:30743516

Abstract

Eggplant (Solanum melongena L.) belongs to the family Solanaceae and is an important vegetable cash crop grown in most parts of Oman. In February 2010, plants showing phyllody symptoms and proliferation of shoots resembling those caused by phytoplasma infection were observed at Khasab, 500 km north of Muscat. Total genomic DNA was extracted from healthy and two symptomatic plants with a modified (CTAB) buffer method (2) and analyzed by direct and nested PCR with universal phytoplasma 16S rDNA primers P1/P7 and R16F2n/ R16R2, respectively. PCR amplifications from all infected plants yielded an expected product of 1.8 kb with P1/P7 primers and a 1.2-kb fragment with nested PCR, while no products were evident with DNA from healthy plants. Restriction fragment length polymorphism (RFLP) profiles of the 1.2-kb nested PCR products of two eggplant phyllody phytoplasma and five phytoplasma control strains belonging to different groups used as positive control were generated with the restriction endonucleases RsaI, AluI, Tru9I, T-HB8I, and HpaII. The eggplant phytoplasma DNA yielded patterns similar to alfalfa witches'-broom phytoplasma (GenBank Accession No. AF438413) belonging to subgroup 16SrII-D, which has been recorded in Oman (1). The DNA sequence of the 1.8-kb direct PCR product was deposited in GenBank (Accession No. HQ423156). Sequence homology results using BLAST revealed that the eggplant phyllody phytoplasma shared >99% sequence identity with Scaevola witches'-broom phytoplasma (Accession No. AB257291.1), eggplant phyllody phytoplasma (Accession No. FN257482.1), and alfalfa witches'-broom phytoplasma (Accession No. AY169323). The RFLP and BLAST results of 16S rRNA gene sequences confirm that eggplant phyllody phytoplasma is similar to the alfalfa phytoplasma belonging to subgroup 16SrII-D. To our knowledge, this is the first report of a phytoplasma of the 16SrII-D group causing witches'-broom disease on eggplant in Oman. References: (1) A. J. Khan et al. Phytopathology 92:1038, 2002. (2) M. A. Saghai-Maroof et al. Proc. Natl. Acad. Sci. USA, 81:8014, 1984.

摘要

茄子（Solanum melongena L.）属于茄科，是阿曼大部分地区种植的一种重要蔬菜经济作物。2010年2月，在马斯喀特以北500公里处的哈萨卜发现了表现出叶变症状和类似植原体感染所致嫩枝增生的植株。采用改良的（十六烷基三甲基溴化铵）缓冲液法（2）从健康植株和两株有症状的植株中提取总基因组DNA，分别用通用植原体16S rDNA引物P1/P7和R16F2n/R16R2进行直接PCR和巢式PCR分析。所有受感染植株的PCR扩增产物用P1/P7引物产生预期的1.8 kb产物，巢式PCR产生1.2 kb片段，而健康植株的DNA未产生明显产物。用限制性内切酶RsaI、AluI、Tru9I、T-HB8I和HpaII对两株茄子叶变植原体的1.2 kb巢式PCR产物和作为阳性对照的属于不同组的五个植原体对照菌株进行限制性片段长度多态性（RFLP）分析。茄子植原体DNA产生的图谱与阿曼记录的属于16SrII-D亚组的苜蓿丛枝植原体（GenBank登录号AF4384（1）。1.8 kb直接PCR产物的DNA序列已存入GenBank（登录号HQ423156）。使用BLAST的序列同源性结果显示，茄子叶变植原体与草海桐丛枝植原体（登录号AB257291.1）、茄子叶变植原体（登录号FN257482.1）和苜蓿丛枝植原体（登录号AY169323）的序列同一性大于99%。16S rRNA基因序列的RFLP和BLAST结果证实，茄子叶变植原体与属于16SrII-D亚组的苜蓿植原体相似。据我们所知，这是16SrII-D组植原体在阿曼导致茄子丛枝病的首次报道。参考文献：（1）A. J. Khan等人，《植物病理学》92:1038，2002年。（2）M. A. Saghai-Maroof等人，《美国国家科学院院刊》，81:8014，1984年。