EFFECT OF POTATO YELOW VEIN: TRANSMITED BY THE VECTOR TRIALEURODES VAPORARIORUM ( WESTWOOD) IN POTATO

Abstract

There is scarce knowledge of the disease "potato yellow vein", its etiology, physiology, epidemiology, and ecology. It has been proved, under greenhouse conditions, that the green­house whitefly Trialeurodes vapora­riorum (Westwood) (Homoptera: Aleyrodidae) is a vector of the disease. Field studies were conducted in order to evaluate distribution, severity, and losses due to "potato yellow vein" in the potato growing area of Antioquía (Colombia); these data were correlated with population studies of the vector and several of its plant hosts. The disease causes yield reduction of 41,82% in var "capiro" and of 53,76⁰/o in var "picacho". There was a significant reduction in tubers, regard­ing their size and the number of them. None of the plant parts: stems, leaves, flowers, tubers suffered structural deformations. Vein yellowing starts 25 days after sprout development, it reaches its peak at 50-60 days ago; but does not show anymore as soon as plant maturity 40 and 100% occurred in El Santuario, Marinilla, Guarne, and Rionegro area at 2.100 m.a.s.I., where mixed crops potato-dry bean allow explosive development of the insect vector, a major pest of dry beans. The lowest incidence of disease occurred in the La Unión area, at 2.500 m.a.s.l.