Reproduction of Meloidogyne chitwoodi Golden et al., 1980 (Tylenchida: Meloidogynidae) on different potato cultivars and its effect on plant growth

The Columbia root-knot nematode, Meloidogyne chitwoodiGolden et al., 1980 (Tylenchida: Meloidogynidae), is one of the most damaging nematode parasites of potato. It can cause economic damage in many cultivated plants and infest weeds. In this study, the reproduction of M. chitwoodiwas assessed in 19 potato cultivars and one candidate cultivar under climate chamber conditions, and the effects of M. chitwoodion plant growth were assessed in a greenhouse in 2014. Meloidogyne chitwoodireproduced well on the potato cultivars tested based on numbers of egg and egg mass, reproduction factor and egg mass index. There were approximately 2-fold differences between some cultivars according to minimum and maximum values of the number of egg masses (205 in Challenger and 423 in Adora) and reproduction factor (28.2 in Marabel and 58.6 in Adora). Some plant growth parameters were significantly different between nematode inoculated and uninoculated plants for each cultivar according to t-test. Additionally, significant percentage decreases for some plant growth parameters were recorded, including plant height (7.6-13.4%), fresh (14.6-24.5%) and dry (14.2-26.7%) weights of shoots, fresh (15.0-25.1%) and dry (16.2-26.2%) root. It was found that all potato cultivars tested were susceptible to M. chitwoodi, and the degree of adverse effect on their growth varied between cultivar