Can C, Ozkilinc H, Kahraman A, Ozkan H
Faculty of Science and Letter, Biology Department, University of Gaziantep, Gaziantep, Turkey.
Faculty of Agriculture, Field Crop Department, University of Harran, Sanliurfa, Turkey.
Plant Dis. 2007 Jul;91(7):908. doi: 10.1094/PDIS-91-7-0908C.
In July 2005, small (2 to 5 mm), elongated, dark brown spots on the stems of Cicer pinnatifidum Jaub. & Spach. were observed on plants grown in the rocky hills of the Kahramanmaras Province. To understand this phenomenon, field trips to Kahramanmaras, Adiyaman, and Sanliurfa provinces were conducted in the summer of 2006. C. pinnatifidum plants exhibiting symptoms similar to Ascochyta rabiei (Pass.) Lab. were collected during May and June. The plants had flowers and pods with seeds at the time of collection. Ascochyta blight symptoms on stems were not extensive. None of the plants had leaf symptoms, but one plant had lesions on its pods. Twelve plants exhibiting Ascochyta blight symptoms were taken to the laboratory, and necrotic parts were used for isolation of the fungi on potato dextrose agar (PDA). After 3 to 5 days of culturing on PDA, characteristic beige-to-dark brown colony development of A. rabiei from explants was observed and five isolates from different locations were recovered. The fungal colony growth was slow and limited conidia formed on PDA. The isolates were also cultured on chickpea meal agar (CMA) and Czapek Dox Agar (CDA) media. Abundant conidia formation occurred only on CMA, 10 to 12 days after culturing. Conidia were one-celled similar to that of A. rabiei of chickpea and single-spore isolations were done. C. pinnatifidum and chickpea cv. Gokce (C. arietinum L.) were inoculated with spore suspensions of 5 × 10 spores per ml (2). Ten- to twelve-day-old seedlings were used for inoculation in the experiments. Brown-black lesions at the crown region on C. pinnatifidum seedlings were observed 9 to 10 days after inoculation, and characteristic Ascochyta blight symptoms on stems developed on chickpea cv. Gokce. The fungus was reisolated from the infected seedlings. For molecular characterization, mating type of the isolates was determined by PCR using A. rabiei specific Tail1, Com1, and Sp21 primers (1). A single band of Mat 1.2 specific 500- bp product was amplified by PCR from five of the A. rabiei isolates of C. pinnatifidum. This confirmed that the isolates from C. pinnatifidum are A. rabiei. References: (1) M. P. Barve et al. Fungal Genet. Biol. 39:151, 2003. (2) M. S. A. Khan et al. Plant Pathol. 48:230, 1999.
2005年7月，在卡拉曼马拉什省石山生长的鹰嘴豆（Cicer pinnatifidum Jaub. & Spach.）植株茎上观察到有小的（2至5毫米）、细长的、深褐色斑点。为了解此现象，2006年夏天对卡拉曼马拉什省、阿迪雅曼省和桑尼乌法省进行了实地考察。在5月和6月收集了表现出与鹰嘴豆壳二孢（Ascochyta rabiei (Pass.) Lab.）相似症状的鹰嘴豆植株。收集时这些植株有花和带有种子的豆荚。茎上的壳二孢叶枯病症状并不广泛。没有植株有叶片症状，但有一株植株的豆荚上有病变。将12株表现出壳二孢叶枯病症状的植株带到实验室，坏死部分用于在马铃薯葡萄糖琼脂（PDA）上分离真菌。在PDA上培养3至5天后，观察到外植体上出现了壳二孢典型的米色至深褐色菌落生长，并从不同地点分离出5个菌株。真菌菌落在PDA上生长缓慢且形成的分生孢子有限。这些菌株也在鹰嘴豆粉琼脂（CMA）和察氏琼脂（CDA）培养基上培养。仅在CMA上培养10至12天后出现大量分生孢子形成。分生孢子为单细胞，与鹰嘴豆的壳二孢相似，并进行了单孢分离。用每毫升含5×10个孢子的孢子悬浮液接种鹰嘴豆和鹰嘴豆品种Gokce（C. arietinum L.）（2）。实验中使用10至12日龄的幼苗进行接种。接种9至10天后，在鹰嘴豆幼苗的冠部区域观察到棕黑色病变，鹰嘴豆品种Gokce的茎上出现典型的壳二孢叶枯病症状。从受感染的幼苗中重新分离出该真菌。为进行分子鉴定，使用壳二孢特异性引物Tail1、Com1和Sp21通过PCR确定分离菌株的交配型（1）。通过PCR从5个鹰嘴豆壳二孢分离菌株中扩增出一条Mat 1.2特异性500碱基对产物的单条带。这证实了从鹰嘴豆分离出的菌株是壳二孢。参考文献：（1）M. P. Barve等人，《真菌遗传学与生物学》39:151，2003年。（2）M. S. A. Khan等人《植物病理学》48:230，1999年。
