Pythium oligandrum in the control of Fusarium rot on some bulbous plants.

Pythium oligandrum was applied as tulip bulbs or gladiolus corms soak prior or after inoculation with formae speciales Fusarium oxysporum. The mycoparasite used before inoculation with pathogen suppressed the development of Fusarium rot. This effect was not observed, however, when P. oligandrum was used 24 hr after bulb inoculation. Soaking of forced tulip bulbs in oospore suspension of P. oligandrum may reduce Fusarium rot spread and increase number of flowers, but at conc. 2.5 x 10(3)-10(4)/cm3 caused inhibition of tulip root growth.