Fruit rot on olive caused by Pilidium concavum in Iran

Abstract

A new fruit rot disease was observed on olive fruits (Olea europaea L.) in the orchards of the Tarom region (Zanjan province, Northwest Iran). The symptoms of the disease appeared as water-soaked lesions on fruits, later becoming brownish and coalescing, which resulted in rotten and mummified fruits. Isolation was made from symptomatic tissues. The causal agent of the disease was identified as Pilidium concavum based on morphological and cultural characteristics. The identity of the species was further confirmed using sequence data from ITS-rDNA region. The ITS sequence generated in this study showed 100 % homology with the sequence data for P. concavum from GenBank. Koch's postulates were fulfilled by inoculation of surfacesterilized fresh olive fruits under laboratory conditions using a spore suspension. This is the first report of the occurrence and pathogenicity of P. concavum on olive fruits anywhere in the world.