Causal organism: Podosphaera xanthii

Symptoms:

• First appears as pale yellow spots on older leaves
• These spots enlarge as the white, fluffy mycelium grows over leaves surfaces
• Severely attacked leaves become brown and shrivelled and defoliation may occur

Management:

• Use recommended fungicides at initial stage of disease development (Refer: Pesticide recommendation DOA, 2019)
• Distraction of infected plant debris after harvest

 Causal organism: Pseudoperonospora cubensis 

Symptoms:

• Angular yellow spots that are limited by the leaf veins on the upper surface of the leaves.
• Leaves become chlorotic and finally necrotic and host plant cells die

Management:

• Use recommended fungicides at initial stage of disease development (Refer: Pesticide recommendation DOA, 2019)
• Distraction of infected plant debris after harvest

Causal organisms:  Sclerotium spp., Fusarium spp.

Symptoms:

• Initially the plants show temporary wilting symptoms
• The leaves yellowing, loose turgidity and show drooping
• Eventually, the plant dies.
• Vascular bundles in the collar region become yellow or brown.

Management:

• Destroy infected plants with soil
• Improved drainage

• Use recommended fungicides at initial stage of disease development (Refer: Pesticide recommendation DOA, 2019)

Causal organisms: Didymella bryoniae

Symptoms:

• Lesions on leaves and fruit usually begin as spreading water-soaked areas
• The former these may have a chlorotic halo, become light brown and irregular in outline
• Dark cracked sunken lesions on fruit
• Plant collapse where sunken, girdling cankers
• Spots on stems often elongate into streaks and gummy exudates may occur from cracks
• Dark brown to black fruiting bodies (pycnidia) can be seen on fruit, stem, or leaf

Management:

• Crop debris should be ploughed deeply immediately after harvest to reduce fungus survival
• Use recommended fungicides at initial stage of disease development (Refer: Pesticide recommendation DOA, 2019)