A PATHOGENIC AND BIOCHEMICAL COMPARISON OF TWO SPANISH POPULATIONS OF THE CEREAL CYST NEMATODE
AbstractA series of pathogenicity tests, biochemical (2-D PAGE protein patterns, isozymes) and molecular (-RAPD/PCR) techniques, were used to compare two Spanish populations of the cereal cyst nematode from Santa Olalla (P1) and from Torralba de Calatrava (P2). Previous morphometric studies defined P1 as a member of the strict Heterodera avenae group and P2 as a member of the "Gotland strain" or "British pathotype 3" of H. avenae. The two populations were found to belong to the resistance groups Ha1 and Ha2 respectively. The 2-D protein patterns of the two populations differed by at least 12 polypeptides. Of the eight isozyme systems analyzed, six differed in number, concentration and relative mobility of bands. Catalase isozymes are suggested as an enzymatic system for routine use in the biochemical characterization of nematodes. Of 43 markers obtained by the RAPD technique, 31 showed differences between the two populations. These results, along with the differences described for these populations in a previous morphometric study, support the idea that P1 and P2 belong to specific groups. They also help to observe genetic dissimilarity between some members of the H. avenae complex.