Hektar

Main Causes of Flower Drop in Peppers

1. Pathological Factors (Diseases):

• Anthracnose (Colletotrichum spp.):
  • Causes brown or black spots on stems, leaves, and flowers, leading to their drop.
• Bacterial Spot (Xanthomonas campestris pv. vesicatoria):
  • Causes yellow or brown spots on leaves and flowers, weakening them.
• Gray Mold (Botrytis cinerea):
  • Produces gray mold on flowers, making them fragile and prone to falling.
• Powdery Mildew (Leveillula taurica):
  • Weakens the plant and directly affects flower health.

2. Environmental Factors and Stress:

• Extreme Temperatures:
  • High temperatures (>30°C) or low temperatures (<15°C) can inhibit pollination, causing flower drop.
• Excessive or Insufficient Humidity:
  • Very high humidity (>85%) promotes disease, while low humidity (<50%) stresses the plant.
• Inconsistent Watering:
  • Irregular irrigation, whether excessive or insufficient, leads to water stress.
• Insufficient Light:
  • Lack of sunlight reduces photosynthesis, weakening the plant and causing flower drop.
• Excessive Nitrogen Fertilizer:
  • Encourages vegetative growth at the expense of flower stability, causing them to fall.

Associated Symptoms of Flower Drop:

• Flowers become weak and fall before fully opening.
• Buds may wither before developing.
• Poor pollination may be evident through reduced fruit formation.

Prevention and Control Methods:

1. Disease Control:

• Apply preventive fungicides such as:
  • Copper-based products (copper oxychloride, copper hydroxide).
  • Mancozeb or captan-based treatments.
• Use biological fungicides (e.g., Trichoderma or Bacillus subtilis) for natural protection.
• Remove infected plant debris and maintain a clean environment around the crop.

2. Ensuring Optimal Conditions:

• Temperature:
  • Protect plants in greenhouses or tunnels to avoid temperature fluctuations.
• Humidity:
  • Maintain moderate humidity with drip irrigation and proper ventilation.
• Irrigation:
  • Water regularly, avoiding excessive dryness or waterlogging.
• Fertilization:
  • Use balanced fertilizers with appropriate N-P-K ratios (e.g., 10-20-20) to promote flowering and fruiting.

3. Improving Pollination:

• Attract pollinators (e.g., bees) or use artificial methods, such as gently shaking the plants.
• Ensure good air circulation to aid natural pollination.