Selected silicon fertilizers and inducing agents applied by foliar sprays compared for the control of Venturia inaequalis and V. pirina on leaves of apple (Malus cv. Golden Delicious) and pear (Pyrus communis ‘Williams’ Bon Chrétien’), respectively, as measured by an observed leaf scab severity indexz.
| Treatment | Apple scab severity on leavesy | Pear scab severity on leavesy | ||
|---|---|---|---|---|
| 2014 | 2015 | 2014 | 2015 | |
| Water (control) | 4.8a | 5.0a | 3.4a | 3.4a |
| Sil-MATRIX (10 ml liter of water) | 2.7bc | 3.0bc | 2.4b | 2.4b |
| Salicylaldehyde | 3.0b | 3.2b | 2.2b | 2.4b |
| Fossil (10 ml liter of water) | 2.3bc | 2.2bcd | 1.9b | 2.0bc |
| Sirius (10 ml liter of water) | 2.3bc | 2.4bcd | 1.8b | 2.0bc |
| Rigel (3 ml liter of water) | 1.6cd | 1.8de | 1.6bc | 1.4cd |
| Topas (1.5 ml liter of water) | 0.4d | 0.8e | 0.8c | 1.0d |
| Treatment | <0.001 | <0.001 | <0.001 | <0.001 |
↵z Scab severity index: 0 = no scab observed; 1 = less than 5% of leaves affected and no aesthetic impact; 2 = 5%–20% of leaves affected with some yellowing but little or no defoliation; 3 = 21%–50% of leaves affected, significant defoliation, and/or leaf yellowing; 4 = 51%–80% of leaves affected, severe foliar discoloration; 5 = 81%–100% of foliage affected with 90%–100% defoliation.
↵y Mean of ten randomized complete blocks with one tree per block.
Note: Lowercase letters indicate significant differences between means for each evaluation date by Tukey highly significance test (P = 0.05).