Effects of Tannin to Control Leaf Blight Disease on Toona sureni Merr. Caused by Two Isolates of Rhizoctonia sp

This study investigated the efficacy of tannin in order to control leaf blight disease on Toona sureni caused by Rhizoctonia sp. by measuring disease intensity and percentage of leaf damages. Two Rhizoctonia sp. (R1 and R2) isolates were induced on the T. sureni leaves. Tannin solution with concentration of 0.5, 1, 2 and 3% and control (water) were sprayed on the leaves surface every two days. The percentage of disease sign on the leaves was measured every two days for one month. Results revealed that all tannin solution treatments reduced intensity and leaf death percentage. No poisonous impacts on the seedling were observed. The highest tannin concentrations which reduce disease activity were 3% for both isolates. It reduced the disease by stopping the fungal enzymatic activity of cellulolytic and pectinolytic. The highest increase of disease intensity and the percentage of leaf death was found in the control treatment. It can be concluded that, tannin could be used to control leaf blight disease on Toona sureni caused by Rhizoctonia sp.