02471nam a2200193 a 450000100080000000500110000800800410001910000200006024500890008026000860016950000900025552018170034565000110216265000220217370000180219570000170221370000230223070000240225317488482023-08-02       2009    bl uuuu     u00u1 u    #d1 aKITAJIMA, E. W.  aCitrus leprosis in Florida may have been of the nuclear type.h[electronic resource]  aVirus Reviews & Research, Rio de Janeiro, v. 14, p. 90, 2009. Suplemento 1.c2009  aTrabalho apresentado no XX Encontro Nacional de Virologia, Brasília, DF. Resumo 098.  aA citrus disease characterized by stem, leaf and fruit lesions was first reported in Florida in the early 1900's and referred to as scaly bark or nail head rust. It disappeared from citrus grooves before the 1970'. Similar disease was observed on sweet orange plantations in Argetina and Paraguay around 1930' and named "lepra explosiva" and also in Brazil, where it was first called "varíola" and later "leprose". Basedon symptom and association with Brevipalpus mites, both diseases were considered similar by 1950" and they were referred to as citrus leprosis. Further investigations revealed that there are two different viruses causingsymptoms of leprosis on citrus, both transmitted by Brevipalpus mites: cyto plasmic type (CiLV-C, a Cilevirus) and nuclear type ( CilV-N, possibly Dichorhabdovirus). CiLV-C is the prevalent form and has been found from Argentina to Mexico in the American continent. CiLV-N is rare and was found in cooler areas of Panama and Brazil (states of S. Paulo and R.G. Sul). Leaf lesions caused by CiLV-C are pale green, usually with concentric gummy rings while those caused by CiLV-N are smaller, with a necrotic center surrounded by a bright yellow halo. Examination of published nictures of leprotic leaf lesions from Florida gave a hint that they could br caused by CiLV-N. Herbarizedmaterial of leprosis from Florida, received by Dr. A. A. Bitancourt, and mantained at the Instituto Biológico was analyzed. Though dried, leaf symptoms in this material strongly resemble those caused by the CiLV-N. Other herbarized materials from different sources (Argentina and Brazil) clearly exhibit symptoms caused by the CiLV-C. Attempts to detect CiLV-C RT-PCR are being made, but preliminary results have been negative, possibly due to the fact that samples are about 60 years old.  aCitrus  aDoença de Planta1 aCHAGAS, C. M.1 aHARAKAWA, R.1 aFREITAS-ASTÚA, J.1 aRODRIGUES, J. C. V.