ARS | Publication request: Supression of Powdery Mildew and Gray Mold of Begonia Induced by Trichoderma Hamatum 382 in Peat and Compost Amended Potting Mixes

Submitted to: Phytopathology
Publication Type: Abstract
Publication Acceptance Date: May 4, 2003
Publication Date: June 1, 2003
Reprint URL: http://www.ars.usda.gov/sp2UserFiles/Place/36071000/Posters/Horst147050_2003_Suppression.pdf
Citation: Horst, L., Krause, C.R., Madden, L.V., Hoitink, H.A. 2003. Supression of powdery mildew and gray mold of begonia induced by trichoderma hamatum 382 in peat and compost amended potting mixes. Phytopathology. 93(6):537.

Technical Abstract: Composts may induce systemic resistance (ISR) in plants against root as well as foliar diseases. Unfortunately, this effect is highly variable in nature. For example, less than 2% of 85 different batches of composts tested naturally induced ISR in plants. This research shows that Trichoderma hamatum 382 (T382) inoculated into a light Sphagnum peat mix significantly reduced the severity of powdery mildew and of gray mold of begonia. Plant dry weight and salability also were increased significantly. Amendment of the potting mix with a batch of composted cow manure (5%; v/v) that naturally induced ISR in plants also significantly decreased the severity of these diseases. T382 and the ISR-active compost suppressed grey mold and powdery mildew as effectively as foliar sprays with Daconil and Pipron, respectively.