Incidencia del Virus de la hoja amarilla de la caña de azúcar en la colección de germoplasma en Cuba

Yellow leaf disease, caused by Sugarcane yellow leaf virus (SCYLV), was informed for the first time in Cuba in 1999. The manifestation of symptoms related with this disease in the germplasm collection has been studied previously, but without a method of laboratory diagnostic to confirm their presence. The objectives of the present study were determine the natural infection for SCYLV in the germplasm collection in Matanzas, Cuba; evaluate the disease severity and, in a preliminary way, identify the possible available resistance resources. 1603 individuals were evaluated by means of Tissue blot immunoassay (TBIA). The presence of the virus was also confirmed by Reverse Transcription of Polimerase Chain Reaction (RT-PCR). This is the most extensive study carried out so far with the purpose of determining the infection for SCYLV in a germplasm collection. Grades 2 and 3 of SCYLV severity were the most frequent in the evaluated collection. The diagnosis methods used detected infections in plants with symptoms and asymptomatics. Infections by SCYLV were determined in 670 individuals of different genetic origins, and a group of 291 individuals with possible resistance to SCYLV was identified. SCYLV uninfected individuals most be taken into account in genetic improvement programs, in order to obtain disease-resistant cultivars.