Note: Not all indicated timings may be necessary for disease control.
| Disease | Spring root flush | Fall root flush | Oct./Nov. | Jan./Feb. | March | 5 to 1 wk PHI |
|---|---|---|---|---|---|---|
| Alternaria rot1 | 0 | 0 | 0 | 0 | 0 | 1/2 |
| Anthracnose2 | 0 | 0 | 0 | 0 | 0 | 3 |
| Greasy spot2 | 0 | 0 | 0 | 0 | 0 | 3 |
| Phytophthora brown rot | 0 | 0 | 3 | 3 | 2 | 1 |
| Phytophthora root rot | 3 | 3 | 0 | 0 | 0 | 0 |
| Rind disorder3 | 0 | 0 | 3 | 2 | 1 | 0 |
| Septoria spot | 0 | 0 | 3 | 3 | 1 | 0 |
| Rating: 3 = most effective, 2 = moderately effective, 1 = least effective, and 0 = ineffective |
| 1 Alternaria fruit rot management with fungicides is generally low (1) with preharvest fungicide applications before wet weather (the current understanding of the epidemiology of the disease is limited). |
| 2 Anthracnose and greasy spot management is generally high (3) with preharvest applications before warm, wet weather. |
| 3 Management of rind disorder especially on early-season mandarins (e.g., Satsuma) is generally high (3) provided that fruit are harvest within 6 to 8 weeks of color break. Other mid- and late-season cultivars have less problems unless high rainfall is observed. Treatment timing should be at color break. Repaeat applications may be necessary. |
Acknowledgment: Adaskaveg et al., 2022. Fungicides, Bactericides, Biocontrols, and Natural Products for Deciduous Tree Fruit and Nut, Citrus, Strawberry, and Vine Crops in California. (PDF)