Isolation, morphological and molecular characterization of alternaria species affecting some crops grown in Çukurova region

In this study, during 2010-2012 suspicious plant samples infected with Alternaria spp. showing fruit rot with dark black and brown leaf spot, and concentric lesion with brown and black spot from different infected crops in Çukurova region were collected. Alternaria spp. were isolated from infected leaf tissues and fruits of pepper, tomato, eggplant, cucumber, citrus and pomegranate and sub-cultured on PDA medium with supplemented 100 mg/l streptomycin. Micelle was grown with dark olive green and grey color. Morphology of micelle and spores were checked under a light microscope with different magnitude. Liquid culture of Alternaria spp. isolates and toxins were tested on different plant leaves and all tested plants have been shown severe lesions to toxins of A. solani and A. alternate f.sp. citri isolated from tomato fruit and ?Fremont? mandarin. The most sensitive host plant to toxins was eggplant leaf. ITS/5.8S DNA region was amplified approximately 620 bp from all Alternaria spp. isolates and 2 different DNA bands (480 and 140 bp) were obtained from all ITS/5.8S region by digestion of MspI and HaeIII RE. ITS/5.8S DNA sequences were homogenous in all isolates with 98 and 99 % ratio.Key Words: Alternaria spp., ITS/5.8S, PCR, RFLP, Tox