Effect of potassium, silicon fertilizers and vermicompost on controllingRhizoctonia rot (Rhizoctonia solani) inPinto bean

With consideration to environmental risks and appearance of resistance in pathogens due to use of chemical pesticides, application of other managing measures such as cultural methods can be useful in controlling Rhizoctonia rot. This experiment was conducted to investigate the effects of potassium, silicon and vermicompost on controlling of Rhizoctonia rot (Rhizoctonia solani) of pinto bean. A factorial pot experiment with four replication was conducted in 2014 based on completely randomized design with three factors including potassium (0, 50 and 100 kg ha-1), calcium silicate (0, 400 and 800 kg ha-1) and vermicompost (0 and 5 % V/V). The results showed that main factors increased vegetative growth parameters of pinto bean and reduced the level of Rhizoctonia rot. So that, application of 100 kg ha-1 of potassium or 400-800 kg ha-1 of calcium silicate and vermicompost significantly increased vegetative growth (root and shoot) fresh and dry weight. The treatments also significantly improved biochemical characteristics such as the amount of gaiacol peroxidase. In general, our results showed that plant nutrient greatly improved plant vegetative parameters and plant resistance to biotic stress. Accordingly, we found that the use of calcium silicate (400 and 800 kg. ha-1) and 100 kg.ha-1 of potassium had highest effect on controlling Rhizoctonia rot and improving plant vegetative growth.