Major Diseases in Protected Cultivation

A. Fungal Diseases

a. Powdery Mildew (Erysiphe spp.)

• White, powdery growth on leaves and stems.
• Thrives in high humidity with moderate temperatures.
• Management: Improve ventilation, avoid overhead watering; apply sulfur or triazole fungicides.

b. Downy Mildew (Peronospora spp.)

• Yellow patches on leaves, grayish fungal growth on the underside.
• Favored by high humidity and poor air circulation.
• Management: Maintain dry leaves, copper-based fungicides, and resistant varieties.

c. Botrytis Gray Mold (Botrytis cinerea)

• Gray mold on flowers, buds, and fruits.
• Overcrowded plants with high humidity are highly susceptible.
• Management: Remove infected tissue; apply iprodione or biofungicides.

d. Fusarium Wilt (Fusarium oxysporum)

• Causes yellowing, wilting, and stunted growth.
• Soil-borne, difficult to manage once established.
• Management: Resistant varieties, soil solarization, proper crop rotation.

e. Pythium and Phytophthora Root Rot

• Symptoms: Root decay, stunted plants, water-soaked lesions.
• Management: Ensure proper drainage, avoid overwatering, apply systemic fungicides (mefenoxam).

f. Other

• Damping-off (Pythium, Phytophthora, Rhizoctonia,Botrytis, Sclerotinia)
• Black root rot (Chalara elegans)
• Foot and root rots (Pythium)
• Foot and root rots (Rhizoctonia solani)
• Basal stem rot (Phytophthora capsici)
• Buckeye rot (Phytophthora nicotianae)
• Root rots (Fusarium)
• Fusarium oxysporum f. sp radicis lycopersici
• Verticillium wilt (Verticillium dahliae)
• Fusarium wilt (several specialized forms of Fusarium oxysporum)
• Black stem rot (Didymella bryoniae)
• Grey mould (Botrytis cinerea)
• Sclerotinia (Sclerotinia sclerotiorum)
• Tomato blight (Phytophthora infestans)
• Downy mildew (Pseudoperonospora cubensis)
• Powdery mildew of the Cucurbitacae (Podosphaera fusca)
• Powdery mildew of the Solanaceae (Leveillula taurica)
• Tomato alternaria canker (Alternaria dauci )

B. Bacterial Diseases

a. Bacterial Leaf Spot (Xanthomonas spp.)

• Small, dark, water-soaked lesions on leaves; leaf drop.
• Management: Sanitation, copper-based sprays, disease-free transplants.

b. Bacterial Wilt (Ralstonia solanacearum)

• Sudden wilting without yellowing initially.
• Soil-borne; difficult to control once established.
• Management: Remove infected plants, sterilize soil/substrate, crop rotation.

c. Other

• Tomato bacterial speck (Pseudomonas syringae pv.tomato)
• Tomato pith necrosis (Pseudomonas corrugata)
• Leaf spot (Xanthomonas campestris)
• Angular leaf spot of the Cucurbitacae (Pseudomonassyringae pv. lacrimans)
• Bean bacterial speck (Pseudomonas syringae pv.phaseolicola)
• Fruit scab (Xanthomonas campestris)
• Soft rots of stems, leaves and fruits (Erwiniacarotovora, Pseudomonas fluorescens)

C. Viral Diseases

a. Tomato Leaf Curl Virus

• Leaf curling, stunted growth; vectored by whiteflies.
• Management: Use virus-free transplants, control whitefly populations.

b. Cucumber Mosaic Virus (CMV)

• Mosaic leaf pattern, stunted fruits.
• Management: Remove infected plants, control aphid vectors, use resistant varieties.

Advantages of IPM

• Limited disruption of natural beneficial insects
• Few hazards to human health
• Minimal negative impact on non-target organisms
• Limited environmental damage
• Optimal preservation of natural and manage ecosystems
• Long-term reductions in pest control requirements
• Effective implementation operationally feasiblel Cost efficiency in short and long term