| Abstract: | Blastomyces luteus has been shown to be antagonistic in culture to both Verticillium albo-atrum and V. dahliae over a wide range of temperature and irrespective of the pH value of the medium. When B. luteus is grown on Dox's and potato-dextrose solutions it produces an exudate which, added to agar media, has an inhibiting effect upon the growth of these two species of Verticillium. The effectiveness of this inhibiting material is slightly reduced by boiling for 15 min.
When 'spent' Dox's liquid medium, which has supported the growth of B. luteus , is injected into tomato and antirrhinum seedlings inoculated with Verticillium no control of the disease is effected, but when B. luteus mycelium is added to soil infected with Verticillium , marked reduction in the incidence of disease results when the antagonistic organism and the pathogens have co-existed in the soil a sufficient length of time for the exudate of the former to be effective upon the development of the latter. |
