Characterization of causal agent a disturbance in evergreen bean (Phaseolus polyanthus Greenman) in Nariño and Putumayo

Abstract

In the departments of Nariño and Putumayo, since 2003 has been presenting a disturbance of apparent viral etiology attacking perennial bean (Phaseolus polyanthus Greenman) with symptoms of generalized yellowing, distortion of leaves, shoots and rugose mosaic and growth retardation. The completion of this work was done in the greenhouse and the laboratory of entomology at the University of Nariño, Pasto, Colombia, 2,600m, and an average temperature of 20°C. For the identification was made by collection of infected material for testing mechanical inoculation, aphid and seed transmission. Being able to establish that the efficiency of mechanical transmission in bean Phaseolus polyanthus Greenman is 90% with an end point dilution of 10⁵, its incubation period is 10 days,seed transmission was presented with an efficiency of 66% and the aphid vector was Picturaphis vignaphilus Blanchard with a period acquisition of 2 minutes and 93% efficiency of transmission. In tests with other species was established that in common bean (Phaseolus vulgaris L). is presented mechanical transmission of 83% and 53% by aphid in bean (Vicia faba L) was presented only 33% mechanical transmission, electron microscopy examinations revealed particles 700 x 15nm, shape flexuosa.