Variability in D2/D3 segment sequences of several populations and pathotypes of the Potato Cyst Nematode (Globodera rostochiensis, G. pallida)

摘要

The soil borne Potato Cyst Nematode [Globodera rostochiensis (Wollenweber, 1923), Globodera pallida (Stone, 1973)] is an important pest of potato in the Czech Republic. Although the use of cultivars of potato resistant to G. rostochiensis would decrease the risks to producers of potatoes, there are currently only a small number of cultivars that are resistant to G. pallida and therefore the spread of this species is likely to result in large losses in yield. Moreover, the level of infectivity of some pathotypes of G. rostochiensis is significantly higher than that of pathotype Ro 1, which is currently the only pathotype present in both the Czech and Slovak Republics. For the effective use of resistant cultivars in the field the precise diagnostics of Potato Cyst Nematode pathotypes remains a key factor. The main aims of this work were: (i) to compare sequences of D2/D3 segments of the 28S rDNA gene obtained from three populations of G. rostochiensis and five populations of G. pallida and (ii) to place the researched Globodera populations into the broader context of the Heteroderidae. Resulting phylogenetic analysis showed significant differences between these two species of Potato Cyst Nematode, however, the situation is complicated by presence of a reference population of G. pallida in G. rostochiensis group. The taxonomic status of this reference population needs further verification.