Composts and Trichoderma harzianum as suppressors of Rhizoctonia solani and promoters of lettuce growt

2 tab. 32 ref.Corteza de pino, viruta de pino y viruta de algarrobo compostados, junto con un aislado de Trichoderma harzianum Rifai, fueron evaluados para la supresi?n de Rhizoctonia solani Kuhn y el crecimiento de plantas de lechuga (Lactuca sativa L.) en almacigueras. La supresi?n del pat?geno se evalu? a trav?s de los s?ntomas de la enfermedad hasta los 20 d?as del cultivo. Los compost de madera de pino mostraron un mayor efecto supresor del pat?geno y el de viruta de algarrobo favoreci? su desarrollo. Todos los compost promovieron el crecimiento de las plantas, pero los de viruta de pino y algarrobo triplicaron el peso y aumentaron la altura de las mismas, en un suelo desinfectado con bromuro de metilo. La inoculaci?n de los semilleros con T. harzianum disminuy? la incidencia de la enfermedad y restituy? o aument? los valores de peso y altura de las plantas. Pine bark wood, pine wood shavings, carob wood shavings and a Trichoderma harzianum Rifai isolate were evaluated for the suppression of Rhizoctonia solani Kuhn and the promotion of lettuce (Lactuca sativa L.) growth. The pathogen's suppression was evaluated through the assessment of symptoms of the disease during twenty days. Pine wood compost showed the best suppressive effects on the pathogen, while carob wood shavings promoted its development. All the composts tested promoted plant growth. However, pine and carob wood shavings tripled the weight and increased plant height values in soil disinfected with methyl bromide. When T. harzianum was added to the seed beds, the disease incidence decreased and the weight and height values were restored and/or increased