Factors Affecting Host Efficiency of Potato to Meloidogyne incognita


  • M. Canto-Saenz
  • B. B. Brodie


Root-Knot, Resistance, Nematode Races


The effects of temperature, plant age at inoculation, and method of plant propagation (stem cutting, tuber, or true seed) on host efficiency of one susceptible and two resistant potato clones to 2 races of Meloidogyne incognita were determined. The potato clones studied were derived from a cross of Solanum sparsipilum x (S. phureja x haploid of S. tuberosum). Host efficiency was based on final populaion (Pf) and initial population (Pi) ratios and number of eggs/g of root. Temperature studies were done in controlled growth chambers at 14, 23, 31, and 35 C with 14-hr day length and a light intensity of 17,000 lux. There was no nematode reproduction on any clone at 14 C and reproduction was reduced on the susceptible clone at 23 C. One resistant clone (E2) that was a nonefficient host at 23 C became an efficient host at 31 C and 35 C whereas the resistant clone, N4, was an efficient host only at 35 C. Neither host efficiency nor growth of the resistant clones were affected by plant age