GROWTH OF FUSARIUM-EUMARTII ON CALLUS-TISSUE OF OAK

The reliability of inoculation rests of Fusarium eumartii on callus ti ssue was examined and results compared with the same tests in planta. The parameters examined, colony growth rate, colony appearance, per se nt of callus overgrown by mycelium, growth and branching of the aerial hyphae, length of hyphae, and onset of necrosis revealed significant differences (P = 0.01) between the oak species tested, but not between the F. eumartii isolates (P = 0.01). The effect of temperature was al so rested by incubating the cultures at 15, 20, 25 and 30 degrees C in a controlled-environment chamber with the relative humidity kept cons tant at 75 %. All the test parameters, the optimum growth temperature was 20 degrees C. Findings are in agreement with in planta results obt ained in previous tests. It is concluded that the in vitro test is a r apid and reliable means to study the oak/F. eumartii interaction.