The cultivation of potatoes all over the world has proved that with all the varieties by growing them year for year a depreciation of the vegetative system of the plant takes place. Implicitly, continuously and progressively the initial production potential degenerates. Velican (1959) in his attempt to elucidate the causes and prevention methods for the potato degeneration establishes three basic theories: ecological, physiological aging and virotical. To diminish the percentage of virus-infected plants, a better management of phytosanitary methods in producing seed potatoes is of necessity. Besides this, also a higher proportion of resistant varieties within the admitted assortment is of importance (Iagăru, 2005). The potato represents for Romania a staple food for the population. High altitudes, the existence of natural barriers create natural conditions for isolating crops and therefore reduce virotic disease propagation (Bozeşan, 2003).

potato; the initial production potential degenerates; resistant varieties; altitudes; natural barriers

Presentation: oral