Greenhouse Pests and Diseases Assignment

Pest: Aphids

• Damage: Aphids feed on plant sap, leading to distorted growth and yellowing leaves. They also excrete honeydew, which can promote sooty mold growth.
• Signs of Infestation: Presence of small, soft-bodied insects on new growth; sticky residue on leaves; curled or deformed foliage.
• Primary Cause: Over-fertilization and lack of natural predators in greenhouse environments.
• Susceptible Plants: Tomatoes, peppers, lettuce, and cucumbers.
• Organic Control: Introduce beneficial insects like ladybugs or lacewings; use insecticidal soaps; implement proper sanitation and remove infested plant parts.

Pest: Whiteflies

• Damage: Whiteflies suck sap from plants, causing yellowing, wilting, and stunted growth. They can also transmit plant viruses.
• Signs of Infestation: Tiny white insects fluttering around when plants are disturbed; sticky honeydew on leaves; presence of sooty mold.
• Primary Cause: Warm temperatures and high humidity in greenhouses; introduction through infested plants.
• Susceptible Plants: Tomatoes, cucumbers, poinsettias, and other ornamentals.
• Organic Control: Use yellow sticky traps; introduce parasitic wasps like Encarsia formosa; maintain proper ventilation and remove heavily infested plants.

Disease: Powdery Mildew

• Damage: White, powdery fungal growth on leaves and stems reduces photosynthesis, leading to weakened plants and reduced yields.
• Signs of Infestation: White or gray powdery spots on upper leaf surfaces; distorted or stunted growth.
• Primary Cause: High humidity and poor air circulation in greenhouses.
• Susceptible Plants: Cucumbers, squash, roses, grapes, and tomatoes.
• Organic Control: Improve air circulation; avoid overhead watering; apply sulfur-based fungicides or neem oil; remove and destroy infected plant parts.

Disease: Black Root Rot

• Damage: Causes root decay, leading to poor nutrient and water uptake, resulting in stunted growth and plant death.
• Signs of Infestation: Blackened, decaying roots; yellowing leaves; wilting despite adequate watering.
• Primary Cause: Overwatering and poor drainage; contaminated soil or tools.
• Susceptible Plants: Pansies, vinca, snapdragons, petunias, and other ornamentals.
• Organic Control: Ensure proper drainage; use sterilized soil and tools; remove and destroy infected plants; avoid overwatering.

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