The population dynamics of Meloidogyne chitwoodi on eight potato genotypes was compared to the susceptible cv. Desiree in four glasshouse experiments. The initial nematode densities consisted of log series 2x , with −4 < x < 8. Seinhorst’s logistic model was fitted to the final population densities to estimate the parameters maximum multiplication rate (a), maximum population density (M) and the ratios RSa, RSM and M/a. Average RSa and RSM of the seven resistant genotypes were smaller than 0.29%. The M/a ratios on six resistant genotypes and cv. Desiree were the same, 1.3, indicating Pi independence of RS. One genotype stood out with M/a = 8.6, whereby RSa < RSM. Both RS and M/a were unaffected by pot size or experimental conditions. Screening protocols at Pi = 24 second-stage juveniles (g dry soil)−1 in 2 or 3 kg pots were evaluated for distinctiveness between the two genotype groups. Based on the results, an optimal protocol for a routine resistance test is proposed.
- Maximum multiplication rate (a)
- Maximum population density (M)
- Root-knot nematode
- Tuber infestation
- Tuber quality