Choueiri E, Jreijiri F, El Zammar S, Verdin E, Salar P, Danet J L, Bové J, Garnier M
Agricultural Research Institute of Lebanon, Tal Amara, Rayak, Lebanon.
UMR GDPP, Institut National de la Recherche Agronomique, BP 81, 33883, Villenave d'Ornon cedex, France.
Plant Dis. 2002 Jun;86(6):697. doi: 10.1094/PDIS.2002.86.6.697A.
During a 2001 survey to evaluate the incidence of phytoplasma diseases in Lebanon, samples were collected from plants showing symptoms suggestive of phytoplasmal infections. Samples were also collected from symptomless plants. Sampled hosts from the Bekaa Valley included: 3 samples of tomato (Lycopersicum esculentum), 4 samples of pepper (Capsicum annuum), 10 samples of grapevine (Vitis vinifera) cvs. Chardonnay and Alicante Bouschet; 7 samples of ornamental periwinkle (Catharantus roseus) from the Tyr area; and 4 samples of weeds (Lactucca serratia). DNA was extracted from leaf midveins of diseased and symptomless plants, and from healthy periwinkle, grapevine, tomato, and pepper plants grown in a greenhouse in France. Polymerase chain reaction (PCR) with universal primers for the amplification of phytoplasma ribosomal RNA genes (3) only produced a 1.8-kbp rDNA fragment from symptomatic samples. The amplified DNAs were analyzed by restriction fragment length polymorphism (RFLP) with several restriction enzymes and sequenced. The analysis showed extracts of diseased grapevines, and two periwinkle plants had identical rDNA sequences and restriction profiles of the stolbur cluster (4). The sequences had 98% identity with two European stolbur isolates from grapevine and periwinkle (GenBank Accession Nos. X76428 and AF248959, respectively). In grapevine, the disease induced by the stolbur phytoplasma is "bois noir." Bois noir is present in Europe where its incidence is predominant in northern vineyards and has been reported in Israel (2). To our knowledge, this is the first report of the stolbur/bois noir disease in Lebanon. In tomato and pepper, the restriction profiles and sequences of the phytoplasma rDNAs were identical. Sequencing and phylogenetic analysis indicated that the phytoplasma belonged to the clover proliferation (CP) cluster, as does the eggplant little leaf phytoplasma of solanaceous plants in Asia. They differed from the stolbur phytoplasma, known to infect solanaceaous plants in Europe. Lastly, a phytoplasma belonging to the pigeon pea witches' broom (PPWB) cluster was found in L. serratia and in some periwinkle plants. A phytoplasma of the PPWB cluster was recently shown to be responsible for an emerging lethal disease of almond trees in Lebanon (1). References: (1) E. Choueiri et al. Plant Dis. 85:802, 2001. (2) X. Daire et al. Vitis 36:53, 1997. (3) B. Schneider et al. Pages 369-380 in: Molecular and Diagnostic Procedures in Mycoplasmology. Academic Press, NY, 1995. (4) E. Seemüller et al. J. Plant Pathol. 80:3, 1998.
在2001年一项评估黎巴嫩植原体病害发生率的调查中，从表现出疑似植原体感染症状的植物上采集了样本。也从无症状植物上采集了样本。来自贝卡谷地的采样寄主包括：3份番茄（Lycopersicum esculentum）样本、4份辣椒（Capsicum annuum）样本、10份葡萄（Vitis vinifera）品种霞多丽和阿利坎特布谢的样本；7份来自提尔地区的观赏长春花（Catharantus roseus）样本；以及4份杂草（Lactucca serratia）样本。从患病和无症状植物的叶片中脉，以及在法国温室中种植的健康长春花、葡萄、番茄和辣椒植物中提取DNA。用通用引物进行聚合酶链反应（PCR）以扩增植原体核糖体RNA基因（3），仅从有症状的样本中产生了一个1.8-kbp的rDNA片段。用几种限制性内切酶通过限制性片段长度多态性（RFLP）分析扩增的DNA并进行测序。分析表明，患病葡萄藤和两株长春花植物的提取物具有相同的rDNA序列和stolbur簇的限制性图谱（4）。这些序列与来自葡萄藤和长春花的两个欧洲stolbur分离株分别具有98%的同一性（GenBank登录号分别为X76428和AF248959）。在葡萄藤中，由stolbur植原体引起的病害是“黑木病”。黑木病在欧洲存在，其发生率在北部葡萄园占主导地位，并且在以色列也有报道（2）。据我们所知，这是黎巴嫩首次报道stolbur/黑木病。在番茄和辣椒中，植原体rDNA的限制性图谱和序列是相同的。测序和系统发育分析表明，该植原体属于三叶草增殖（CP）簇，亚洲茄科植物的茄子小叶植原体也属于该簇。它们与已知在欧洲感染茄科植物的stolbur植原体不同。最后，在L. serratia和一些长春花植物中发现了属于木豆丛枝（PPWB）簇的植原体。最近显示，PPWB簇的一种植原体是黎巴嫩一种新出现的杏仁树致死病害的病因（1）。参考文献：（1）E. Choueiri等人，《植物病害》85:802，2001年。（2）X. Daire等人，《葡萄》36:53，1997年。（3）B. Schneider等人，载于《支原体学的分子和诊断程序》，第369 - 380页。学术出版社，纽约，1995年。（4）E. Seemüller等人，《植物病理学杂志》80:3，1998年。
