2 TYPES OF THE EUROPEAN RACE OF GREMMENIELLA-ABIETINA CAN BE IDENTIFIED WITH IMMUNOBLOTTING

Gremmeniella abietina, the causative agent of Scleroderris canker in c onifers, has been separated into three races: European, North American and Asian. Recent studies have suggested that the European race in Fe nnoscandinavia may be divided into two types. We show that these types cannot be identified with their protein patterns obtained under denat uring conditions, but the two types can be separated based upon presen ce or absence of a 26-28 kD immunoreactive double band in western blot ting. Polyclonal antibodies, either crude or purified with preparative western blotting, detected this double band in all tested 25 isolates classified as type B or short tree type but not in any of 27 isolates of type A or large tree type. This immunoassay was used to type 10 un classified isolates. The results indicated that short tree type of the Swedish classification is immunologically identical to the Finnish ty pe B and large tree type is identical to the type A. Thus, in Fennosca ndinavia the European race can be divided into two serovars as previou sly suggested by random amplified polymorphic DNA markers.