SPHAEROPSIS-SAPINEA AND BOTRYOSPHAERIA-DOTHIDEA ENDOPHYTIC IN PINUS SPP AND EUCALYPTUS SPP IN SOUTH-AFRICA

Sphaeropsis sapinea (Fr.: Pr.) Dyke & B. Sutton and the anamorph of Bo trycsphaeria dothidea (Moug.) Ces, et De Not. are morphologically and ecologically similar fungi that cause serious canker and die-back dise ases of Pinus and Eucalyptus spp. respectively in South Africa. In thi s article, the presence of both these fungi as symptomless endophytes in healthy pine and eucalypt tissue was demonstrated. Sphaeropsis sapi nea was present in 50% of young, green P. patula Schl. et Cham., and 9 0% of P. radiata D. Don cones. In contrast, it was virtually absent fr om the cones of P. elliottii Engalm. et Vasey and P. taeda L. Botryosp haeria dothidea, on the other hand, was found to be common in all the Eucalyptus spp. tested, occurring in 93% of E. smithii R. T. Bak., 77% of E. camaldulensis Dehnh., 63% of E. grandis Hill ex Maid. and 57% o f E. nitens (Deane et Maid.) Maid. leaves tested. The enigma of the ra pid ingress of both these fungi in stressed or damaged trees might the refore be explained by their endophytic habit.