Damping off is a common fungal disease that affects young chili seedlings, often causing significant seedling death before they can even get established. It's particularly prevalent in nurseries and greenhouses due to the warm, humid conditions there. Damping-off is a soil-borne fungal disease that negatively affects the vegetables and flowers in your garden, primarily targeting seeds and new seedlings. Damping-off refers to the rotting of stem and root tissues at and below the soil line. In most cases, infected plants will germinate and come up fine, but within a few days, they become water-soaked, mushy, collapse at the base and die.
Characteristics for Identification of damping off disease:
While damping-off disease primarily affects young seedlings, it's rarely seen in established citrus plants. Citrus trees are generally more resistant to the fungi that cause damping-off compared to other crops. However, if you're concerned about young citrus seedlings, here are some characteristics to identify damping-off disease:
On Seedlings:
- Failure to emerge: Seeds fail to sprout or die shortly after germination.
- Stem lesions: Water-soaked lesions at the base of the stem, causing the seedling to topple and collapse.
- Stem thinning: Stalk becomes thin and weak, resembling a "threadbare" appearance.
- Discoloration: Brown or black discoloration around the base of the stem.
Classification:
- Type of Infestation: Disease
- Common Name: Damping off
- Scientific Name: Pythium aphanidermatum
- Category of Plant Disease: Fungal Disease
- Mode of spread: soil borne, Air borne, water borne
- Affected parts of plant: Seed, Root, Stem
Favorable factors for disease/Pest Development
- Warm and humid conditions: Fungi responsible for damping-off thrive in temperatures between 20-30°C and high humidity (above 70%). Overcrowding in greenhouses or nurseries can exacerbate this issue.
- Poor drainage: Soggy soil due to inadequate drainage creates a waterlogged environment ideal for fungal growth and prevents proper root oxygenation, weakening the plant.
- Heavy rainfall or overwatering: Excessive water, especially on top of poor drainage, can saturate the soil and create favorable conditions for fungi.
- Cool temperatures: While ideal temperatures are moderate, cooler conditions (below 20°C) can prolong seedling emergence, increasing their vulnerability to fungal infection.
Symptoms:
- Failure to germinate completely
- Seeds becoming soft and rotten with brown discoloration
- Lack of root development
- Existing roots turning brown or black and rotting
- This is the most affected part.
- Water-soaked lesions appear near the soil line, causing the stem to become:
- Thin and weak
- Soft and mushy
- Eventually collapse ("damping-off")
Control Measures of Damping off disease
Products |
Technical names |
Dosages |
Copper oxychloride 50 % wp |
2gm/ltr |
|
Thiophanate Methyl 70% WP |
250-600 grams per acre |
|
1.5-2 liters per acre |
||
Carbendazim 12 % + Mancozeb 63 % WP |
300-400 grams per acre |
|
Trichoderma Harzianum 1%WP |
Mix 2.5 kg with 50 kg Farm Yard Manure and broadcast in one hectare field before sowing. |
|
Metalaxyl 8 % + Mancozeb 64 % wp |
1.5 to 2 kg per ha |