Haggag Waffa M, Abou Rayya M S M, Kasim N E
Department of Plant Pathology, National Research Center, Dokki, Cairo, Egypt.
Horticulture Crops Technology Department, National Research Center, Dokki, Cairo, Egypt.
Plant Dis. 2006 Dec;90(12):1553. doi: 10.1094/PD-90-1553C.
In May 2006, leaf spots were observed on approximately 60% of 8-year-old pistachio (Pistacia vera L.) trees in an orchard located at Rhafah, north of Sinai, Egypt. These spots were typically circular, or occasionally irregular, with white-to-light tan or gray centers and a purple or brown border measuring 1 to 5 mm in diameter, or occasionally larger on the upper leaf surface. A narrow, brown border surrounded the spot, and with age, the lesion cracked. Spots occasionally turned brown and closed to form blotches. Fungal isolates from the leaf spots were identified as Septoria pistaciae on the basis of characteristics of pycnidia and conidia. From the leaf spots, numerous black pycnidia were found that produced hyaline conidia, 3 to 7 septate, generally filiform although tapering at one end, and measuring 46 to 75 × 3 to 4 μm. Pycnidia were dark, separate, globe shaped with an ostiole from which conidia were extruded, and erupted through the surface of infected plant tissue. Conidia were produced on short conidiophores. Single conidial isolations onto 2% malt agar consistently formed slow-growing, dark green colonies. To confirm the pathogenicity of the isolate of S. pistaciae, a suspension of 5 × 10 conidia per ml in water was applied at 1 ml per leaf to 20 leaves of 10 rooted cuttings of pistachio trees in 30-cm pots. Ten controls were misted with water only. All plants were covered with plastic bags for 48 h on a greenhouse bench. Greenhouse temperatures ranged from 15 to 20°C with a 16-h photoperiod. After 6 days, all inoculated plants developed symptoms, and the fungus was reisolated from lesions. No symptoms were observed on control plants. S. pistaciae was previously reported on pistachio in Texas and Arizona (2,3). Reports included mention of its occurrence in the United States (California), Asia (Armenia Republic of Georgia, India, Israel, Kazakhstan, Kirgizstan, Syria, Turkey, Turkmenistan, and Uzbekistan), and Europe (Albania, France, Greece, Italy, and Portugal) (1). To our knowledge, this is the first report of Septoria leaf spots of pistachio in Egypt. References: (1) T. Andrianova and D. Minler. Septoria pistaciae. Page 159 in: IMI Descriptions of Fungi and Bacteria. CAB International, Wallingford, UK. 2004. (2) A. Chitzanidis. Ann. Inst. Phytopathol. Benaki 10:29, 1956. (3) D. J. Young and T. Michailides. Plant Dis. 73:775, 1989.
2006年5月，在埃及西奈北部拉法的一个果园里，约60%的8年生阿月浑子树（Pistacia vera L.）上发现了叶斑。这些斑点通常为圆形，偶尔不规则，中心为白色至浅褐色或灰色，边缘为紫色或褐色，直径1至5毫米，偶尔在叶片上表面更大。斑点周围有一条狭窄的褐色边缘，随着时间推移，病斑会开裂。斑点偶尔会变成褐色并融合形成斑块。根据分生孢子器和分生孢子的特征，从叶斑中分离出的真菌被鉴定为黄连叶点霉。从叶斑中发现了许多黑色的分生孢子器，产生透明的分生孢子，有3至7个隔膜，通常为丝状，一端逐渐变细，大小为46至75×3至4微米。分生孢子器颜色深，分离，球形，有一个小孔，分生孢子从孔中挤出，通过受感染植物组织的表面突出。分生孢子在短的分生孢子梗上产生。将单个分生孢子分离到2%麦芽琼脂上，始终形成生长缓慢的深绿色菌落。为了证实黄连叶点霉分离株的致病性，将每毫升含5×10个分生孢子的悬浮液以每片1毫升的量施用于30厘米花盆中10株阿月浑子树扦插苗的20片叶子上。10个对照仅喷水。所有植株在温室工作台上用塑料袋覆盖48小时。温室温度为15至20°C，光照周期为16小时。6天后，所有接种的植株都出现了症状，并且从病斑中重新分离出了真菌。对照植株未观察到症状。此前在得克萨斯州和亚利桑那州的阿月浑子上报道过黄连叶点霉（2,3）。报道还提到了它在美国（加利福尼亚州）、亚洲（亚美尼亚、格鲁吉亚共和国、印度、以色列、哈萨克斯坦、吉尔吉斯斯坦、叙利亚、土耳其、土库曼斯坦和乌兹别克斯坦）以及欧洲（阿尔巴尼亚、法国、希腊、意大利和葡萄牙）的发生情况（1）。据我们所知，这是埃及阿月浑子叶点霉叶斑病的首次报道。参考文献：（1）T. Andrianova和D. Minler。黄连叶点霉。载于《IMI真菌和细菌描述》第页159。CAB国际，英国沃灵福德。2004年。（2）A. Chitzanidis。《贝纳基植物病理学会年报》10:29，1956年。（3）D. J. Young和T. Michailides。《植物病害》73:775，1989年。
