Variacion en Virulencia y Agresividad de Globodera Pallida en Clones de Papa Resistentes a las Razas P4A y P5A en Peru


  • J. Llontop
  • J. Franco
  • M. Scurrah


Aggressiveness, Globodera pallida, Plant Breeding, Races, Resistance, Solanum tuberosum, S. vernei, Virulence


The variability in virulence and agressiveness of 20 populations of the potato cyst nematode G. pallida from the Andean region of La Libertad, Peru (2 600-3 500 m.a.s.l.) was determined. Eleven clones selected for their resistance to race P5A as well as some with resistance to P4A, showed good levels of partial resistance to P5A (Pf/Pi = 0.25 to 3.19). Double resistant clones (P4A + P5A) were more effective against race P4A (Huancayo). The clone 278096.10 also confirmed its resistance to this race (Pf/Pi = 0.46). Clones 280090.10 and 280236.6 were the most resistant to all populations (70 and 55%, respectively). The presence of a new virulence group was confirmed and tentatively nominated as race P6A due to its multiplication on all resistant clones. Four groups of aggressiveness were determined. Seventy-five percent of populations were classified as either very aggressive or aggressive and are considered to be the most important. In general, the most virulent populations also were t