Abstract: | A survey of the incidence of Lophodermium seditiosum, L. pinastri and L. conigenum in plantations of Pinus sylvestris in north-east Scotland showed that L. seditiosum predominated on fallen cones and on young needles which tell prematurely in early summer. L. pinastri predominated on old senescent needles which fell in autumn. The incidence of L. conigenum was low on fallen cones and needles and it is not thought that tins species could effectively replace L. seditiosum. It is concluded that the main source of L. seditiosum inoculum for infections in plantations and nearby nurseries is young infected fallen needles on which ascocarps form in late summer and autumn. |