Abstract This study was conducted to check the efficiency of some biocontrol agents on controlling damping-off disease incited by some tested pathogens both in laboratory and under greenhouse conditions. Results showed that all tested BBA’s were effective in reducing the radial growth of the tested damping-off pathogens. Moreover B. subtilis was more effective (65.55%), whereas F. semitictum was the most sensitive to Bacterial biocontrol agents (BBA’s) treatments, where reduction rates attained was 70.83%. On the contrary, M. phaseolina was the least sensitive to BBA’s treatments, where reduction rate was 35.28%. Both the tested BBA’s treatments significantly reduced TIP incidence caused by the tested cucurbit seed-borne pathogens. Reduction rates attained 46.29% and 42.81% in B. cereus and B. subtili respectively, compared with control. Moreover, reduction rates were higher in M. phaseolina and F. semitictum treatments. Treatments with the tested BBA’s result in significant reductions in PRD values. B. cereus realized the highest reduction rates, particularly against F. moniliforme (55.95%). B. subtilis / F. semitictum gave the least effective among the other treatments, were reduction rates in PRD values 47.78%.B. cereus or B .subtilis / F. semitictum induced the highest reduction rates in PTD values (42.62%), the least reduction rates was obtained in F. moniliforme treatments with B. cereus (21.75%). Moreover B. subtilis was the least effective than B. cereus.
Keywords Greenhouse conditions, Biocontrol agents, In vitro, In vivo, Seed-borne Pathogens.