ABSTRACT
Viroids infect plants of great economic importance such as citrus. With the aim of detecting the presence of viroids by molecular methods in citrus trees, five farms in Araruama, Rio de Janeiro State, were evaluated. Twenty-two samples were collected from plants showing dwarfism, trunk cracking and hyponastic response; RNA was extracted from their leaves and the RT-PCR technique was used with specific primers for five viroid species that infect citrus. The result of agarose gel electrophoresis was positive for Citrus exocortis viroid (CEVd), Citrus bent leaf viroid (CBLVd), Hop stunt viroid (HSVd) and Citrus dwarfing viroid (CDVd); the latter was found in all farms and in combination with other viroids. HSVd and CBLVd were present in two farms and CEVd alone in only one farm. Citrus viroid IV (CVd-IV) was not detected in the evaluated samples. Differences in the expression of CEVd-associated symptoms were observed, which may have occurred due to interference of viroid species infecting the same plant. Transmission may have been mechanical through pruning of citrus plants or through viroid-infected seedlings. The use of molecular methods was efficient in identifying the presence of viroids in citrus plants in the state of Rio de Janeiro.
Keywords
Citrus limonia; Phytopathogens; Detection; Reverse Transcriptase-PCR Test
