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1. Guava Wilt

Causal Organism:  Fungus; Fusarium oxysporum f.sp. psidii

Symptoms:

• Guava Diseases wilt a serious disease, is occasionally found, particularly in alkaline soils.
• Browning and wilting of the leaves, discolouration of the stem, and mortality of the branches on one side are the signs.
• The emergence of yellow colouration with mild curling of the leaves of the terminal branches is the first visible indication of the disease.
• All of the damaged branches’ fruits remain undeveloped, hard, and rocky.
• Sometimes the infection encircles the entire stem, causing the plant to wilt.

Management:

• At 15 days, saturate the soil with Brasicol and spray Bavistin (0.1%) around the roots and leaves to reduce infection.

2. Anthracnose

Causal Organism:  Fungus; Gloesporium psidii, Glomerella psidii

Symptoms:

• The affected plants showed signs of die back from the tip of the branch.
• Young shoots, leaves, and fruits are easily connected while still delicate.

Management:

• Spraying the trees with Copper Oxychloride, Cuprous Oxide or Difolatan controls the disease.
• Application of a bioagent, Streptosporangium pseudovulgare, to fruits prior to symptom development.

3. Cercospora Leaf Spot

Causal Organism:  Fungus; Cercospora sawadae

Symptoms:

• Guava diseases, Leaf spot appears, and Water-soaked patches under the leaf are the characteristic symptoms of the disease.
• The older leaves are the most damaged, and the badly impacted leaves curl and fall off.

Management:

• Spraying copper oxychloride at 0.3 per cent can reduce the infection.

4. Guava Scab / Guava Canker

Causal Organism:  Fungus; Pestalotia psidii

Symptoms:

• The fungus mainly attacks the unripe fruits to produce dark scabby lesions, 2-4mm in diameter.
• The scab disfigures the fruits and their market value is considerably reduced.

Management:

• Application of Zineb 20g or Chlorthalonil-20g/10 litres of water during flowering, followed by 15-day interval sprays, aids in disease management.

5. Guava Red Rust

Causal Organism:  Algae; Cephaleuros virescens

Symptoms:

• During the early spring flush, algae affect immature guava leaves.
• Spots on leaves can range from specks to large swaths.
• The disease appears in April and becomes more severe from May through August.

Management:

• Sprays of Copper oxychloride (0.3%) at 15-day intervals can be used to manage alga.

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