VIEW ARTICLE

Physiology and Biochemistry

Contrasting Rates of Protein and Morphological Evolution in Cyst Nematode Species. J. Bakker, Department of Nematology, Agricultural University, Binnenhaven 10, Wageningen, The Netherlands; L. Bouwman-Smits, Department of Nematology, Agricultural University, Binnenhaven 10, Wageningen, The Netherlands. Phytopathology 78:900-904. Accepted for publication 19 January 1988. Copyright 1988 The American Phytopathological Society. DOI: 10.1094/Phyto-78-900.

The genetic differentiation of cyst nematode species that are morphologically nearly indistinguishable was investigated by means of two-dimensional gel electrophoresis (2-DGE) followed by a sensitive silver stain. 2-DGE of total protein extracts from young females revealed an average of 245 polypeptides. The sibling species Globodera rostochiensis and G. pallida were differentiated by 70% of their polypeptides. The closely related species Heterodera glycines and H. schachtii were discriminated by 59% of their polypeptides. These large differences suggest that these nematode species have accumulated protein differences during a period of millions of years without distinct changes in morphology. These observations emphasize the importance of biochemical techniques in plant nematology for species identification and nematode systematics.