Identificación molecular y caracterización de síntomas de aislados virales de naranjilla en 3 especies de la sección Lasiocarpa (S. quitoense, S. hirtum y S. sessiflorum)

Abstract

The naranjilla is an important item for the southern Amazon of Ecuador because it is one of the main sources of income for local families. However, it has great limitations caused by pests and diseases. The lack of information on viral infections in the Amazon south of the Equator, encouraged the realization of this study, whose objective was to determine the molecular identity and characterize the symptoms of asylees viral naranjilla of 4 commercial lots of the canton Palanda in 3 species of the section lasiocarpa (S. quitoense, S. hirtum and S. sessiflorum). Mechanical inoculations of viral isolates were performed in the 3 species and the incidence and severity of symptoms were evaluated. A completely random design was applied and the variables were measured at 20, 25 and 30 dpi. There was a statistically significant difference in the severity variable (Tukey p < 0.05) between the control and the 4 viral isolates in each species. In addition, a higher level of damage caused by isolates was determined in S. quitoense than in S. sessiflorum and S. hirtum. To determine the molecular identity, 16 solanaceaes virus primers were evaluated using the RT-PCR technique. The presence of a viral complex between CMV and PYVV was identified. In addition, the symptomatology of this viral complex was characterized, consisting of intervenal chlorosis, leaf wrinkles, necrosis, mosaics, chlorotic rings, leathery leaves, among others. It is the first report of mixed infection of viruses that infect the naranjilla in Ecuador and is of great value given the obvious deficiencies of information currently available on the causative agents of virosis in this crop.