Abstract
The control effect of chemicals on the root-rot caused by Pythium sp. in Cocoyam (Xanthosoma sagittifolium) was investigated in Sri Lanka. The effect was observed in two treatments: one was the treatment of metalaxyl (ridomil) solution applied to inoculated soil, and the other was the treatment of dipping inoculated sucker to metalaxyl solution in the field, the effect of metalaxyl solution was also investigated. Thirty-seven days after the application of metalaxyl solution, increase of leaf number and plant height was observed and showed well plant growth, and the infectivity index decreased. Treatments of dipping suckers and application of metalaxylto the soil were effective in controlling this disease.
