Evaluation of Different Control Measures against Damping-off in Greenhouse Solanaceous Crops

Increased losses due to damping off disease have been reported recently on protected Solanaceous crops in Lebanon; however, no efficient treatment has been identified. In-pot and field experiments were done in greenhouses to assess the efficacy of several commercial formulations of pesticides in controlling damping off, and determine their effect on plant growth. The treatments were two commercial formulations of biological control agents, Pythium oligandrum and Bacillus subtilis, and a mixture of Mefenoxam+Azoxystrobin. The results showed that Pythium oligandrum has reduced the incidence of damping off by the half comparing to the positive untreated control and was more efficient than B. subtilis, with a disease incidence of 22.2% and 42.2%, respectively, in the pot experiment. In field experiment, the average incidence of the disease was generally low independently from the treatment performed (5.2%) and the evaluation of the growth parameters indicated that both B. subtilis and P. oligandrum formulations were able to enhance the growth of plants compared to the untreated control. Therefore, P. oligandrum could be used in the management of damping-off; however, further research studies are needed in order to optimize its application in the field.