Viroid-Induced Diseases in Ornamental Plants

Viroids are circular, single-stranded RNA molecules which are virus-like pathogen. Up to now, it is mentioned that there are 32 viroid species defined on different host plants. They are divided into two families, Pospiviroidae and Avsunviroidae, depending on the region where they settled in the cell and genome structure. They have a wide host range ranging from perennials to annuals including ornamental plants. Besides they infected ornamental plants, certain viroids can cause latent infections in some of them. In this case, it is possible that the viroids could be spread on larger of areas and transmission to other crops by ornamental plants. This article intends to give information about the viroids identified in the ornamental plants to the present day.