
Phytophthora
Root Or Crown Rot
Phytophthora Cinnamomi
Pathogen:
Oomycete
Type:
Risk to the plant:
CRITICAL



DESCRIPTION
WHO CAUSES IT?
Phytophthora cinnamomi is a pathogen of oomycete origin that affects a wide variety of plants, including blueberry. This organism is capable of surviving in the soil and in the remains of infected plants for long periods. Under favorable conditions, it releases motile zoospores that move through soil water to infect plant roots. The zoospores penetrate the roots, where they form sporangia and produce new zoospores, perpetuating the infection. During periods of drought, the pathogen can form resistance structures, such as chlamydospores and oospores, that allow it to survive until conditions are again favorable for its development. This survival and spread mechanism makes P. cinnamomi particularly difficult to eradicate once it has infected an area.
SYMPTOMS
Root or crown rot caused by Phytophthora cinnamomi in blueberry causes a series of symptoms that significantly affect the health and productivity of the plants. Damage begins at the roots and crown, gradually spreading to other parts of the plant.
- Wilting of leaves and shoots, especially in hot climates.
- Discoloration and necrosis of the roots, turning brown or black.
- Reduction in plant vigor, with slow and weakened growth.
- Premature defoliation, leaving plants naked and vulnerable.
- Collapse and death of individual branches, progressing towards total death of the plant.
- Appearance of dark, watery lesions at the base of the stem.
- Reduced and lower quality fruit production.


TEMPERATURE AND HUMIDITY
15°C - 30°C
70% - 90%

HOW IS IT SPREAD?
Irrigation water, contaminated soil, agricultural tools, infected plant material, machinery movement, surface water flow

HOW TO REMOVE IT?
Home remedies
There are no home treatments
Chemical treatments
• POTASSIUM PHOSPHONATES 51% (Exp. as phosphorous acid) [SL] P/V
• COPPER OXYCHLORIDE 35% (exp. in Cu) [WG] P/P
• CUPROCALCIC SULFATE 12.4% (EXPR. IN CU) [SC] P/V
Authorized treatments in organic farming
• COPPER OXYCHLORIDE 35% (exp. in Cu) [WG] P/P
• CUPROCALCIC SULFATE 12.4% (EXPR. IN CU) [SC] P/V
Insect allies
PREDATORY MITES
LADYBUGS
LACEWINGS
PARASITIC WASPS
HOVERFLIES OR PARASITIC FLIES
PREDATORY BUGS
There are no natural allies
Mycodiplosis oidii (predatory mosquito)





