Detection of natural infection by Cucumber mosaic virus in vegetable crops Natūrali Agurkų Mozaikos Viruso Infekcija Daržovėse

* Corresponding author. E-mail: irena.zitikaite@gmail.com Cucumber mosaic virus (CMV) causing viral diseases in forage, fruit, ornamental and other important plants worldwide has been isolated in Lithuania from vegetable (cucumber, tomato and sweet pepper) species exhibiting mottle-mosaic and distortion of leaves and fruits, and plant stunt symptoms. Diseased vegetable samples were found in Vilnius, Kaisiadorys, Kėdainiai and Sirvintos regions. The detection of CMV was performed on the basis of determining host range, symptom expression on the test plant species, and the morphological properties of the virus particles by the methods of test plants and transmission electron microscopy and by using specific oligonucleotides in the reverse transcription-polymerase chain reaction (RT-PCR). Primers complementary to conserved sequences of CMV RNA were designed, and RT-PCR was directly performed in crude sap extracts of CMV-infected cucumber, tomato and sweet pepper plants. Analysis of PCR products in acrylamide gel electrophoresis revealed amplification of about 540 base pair fragments which were in agreement with the size of the fragment expected from the sequence data. CMV detection in vegetables was confirmed by the RT-PCR technique.