Mildiu
Basil mildew: what it is, how it occurs, and how to effectively eliminate it
Basil Mildew
Peronospora Belbahrii
Pathogen:
Oomycete
Type:
Risk to the plant:
INTERMEDIATE
DESCRIPTION
WHO CAUSES IT?
Peronospora belbahrii is an oomycete that causes the disease known as downy mildew on basil (Ocimum basilicum). This pathogen is particularly problematic in regions with hot and humid climates, where it can cause serious damage to basil crops and significantly reduce their yield and quality.
SYMPTOMS
The disease caused by Peronospora belbahrii in basil manifests itself as yellow Taches on the underside of the leaves, which eventually become covered with white or gray mold. Over time, these Taches can expand and merge, causing wilting and necrosis of the leaves, which negatively affects the health of the plant and its ability to produce healthy, aromatic leaves.
TEMPERATURE AND HUMIDITY
20ºC - 25ºC
80% - 95%
HOW IS IT SPREAD?
Contaminated irrigation water, direct contact, wind-borne spores, contaminated agricultural tools, vegetative propagation, infected seeds.
HOW TO REMOVE IT?
Home remedies
There are no home treatments
Chemical treatments
• AZOXISTROBIN 25% [SC] P/V
• MANDIPROPAMID 25% [SC] P/V
• ORANGE OIL 60g/L [ME] P/S
• POTASSIUM PHOSPHONATES 51% (Exp. as phosphorous acid) [SL] P/V
• CUPRIC HYDROXIDE 13.6% (EXPR. IN CU) + COPPER OXYCHLORIDE 13.6% (EXPR. IN CU) [SC] P/V
• LAMINARIN 4.5% [SL] P/S
Authorized treatments in organic farming
• ORANGE OIL 60g/L [ME] P/S
• CUPRIC HYDROXIDE 13.6% (EXPR. IN CU) + COPPER OXYCHLORIDE 13.6% (EXPR. IN CU) [SC] P/V
• LAMINARIN 4.5% [SL] P/S
Insect allies
PREDATORY MITES
LADYBUGS
LACEWINGS
PARASITIC WASPS
HOVERFLIES OR PARASITIC FLIES
PREDATORY BUGS
There are no natural allies
Mycodiplosis oidii (predatory mosquito)
EFFECTIVE PRODUCTS TO ELIMINATE THIS DISEASE
To prevent and control downy mildew caused by Peronospora belbahrii, it is essential to implement integrated pest management practices. This includes rotating crops to reduce spore buildup in the soil, using resistant varieties where possible, and applying specific fungicides preventatively. In addition, it is important to maintain good ventilation in the crops and avoid excess irrigation, since excessive humidity can favor the spread of the pathogen.
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