Paper Title
Organic Composts For Suppression Rhizoctonia Cotton Damping-Off Disease

Abstract
Agricultural and animal manure composts was tested for their efficiency to suppress RhizoctoniasolaniKuhncotton damping-off incidence. Moreover, the effect of addition of some biocontrol agents to these types of composts on their efficiency was also investigated. The results revealed various inhibition response of R. solanilineargrowth in vitro with tea composts (30-70% growth reduction). The horse manure compost tea was proved to be the most effective one in suppressing growth of R. solani followed by sheep manure compost. In addition, mature composts were more effective than immature ones. The greenhouse studies showed that horse manure compost was the most effective one in reducing the disease incidence followed by sheep manure compost, whereas both of wheat straw and mushroom compost showed the least control values (infection % were 21.44, 27.33, 29.63 and 40.31%, respectively). The improvement in disease suppression was achieved by introducing one or more of the biocontrol agents for each compost. Animal manure composts highly suppressed the disease. Addition of Trichodermaharzianum, to the compost types resulted in higher performance for the composts compared with their separate application, where infection % were 12.91, 18.49, 21.02 and 40.16%, for horse manure, sheep manure, mushroom and wheat straw compost, respectively. The results also showed significant improvement of disease suppression by combining Bacillus subtilis in addition to T. harzianum for each compost (infection % were 10.38, 15.44, 17.82 and 36.68%, respectively). In general, the raw compost applications were more effective than tea compost applications on reducing the incidence of Rhizoctonia damping-off of cotton seedlings. Keywords� R. solani, biocontrol agents, cotton damping-off, compost, T. harzianum, Bacillus subtilis.