Symptom

• Clearing of the veinlets and yellowing of the lower leaves.
• Younger leaves die in succession.
• Petiole and leaves droop and wilt.
• Browning of vascular system.
• Entire plant wilt and die.

Vascular Discolouration		Infected Plant				Macro Conidia		Chlamydospore

Causal Organism

• Fusarium oxysporum f.sp. lycopersii (Sacc.) W.C. Snyder & H.N. Hansen

Asexual spores :

• Microconidia, Macroconidia and Chlamydospore

Macroconidia :

• Three to five cells with pointed or curved edges

Chlamydospores:

• Single or in pairs

Survival and Mode of Spread

Survival :

• In soil as mycelium and chlamydospores

Primary spread:

• Infected debris

Secondary spread:

• Water and planting equipment

Favourable conditions

• Dry weather (high soil temperature) and low soil moisture.

Integrated Disease Management

• Soil solarization.
• Crop rotation.
• Removal of infected plant.
• Seed treatment with Trichoderma asperellum (viride) @ 4g/kg seeds.
• Seedling dip in B. subtilis @ 5g/l and soil application of B. subtilis@ 1.0 kg with 50 kg of FYM/ac at 30 days of transplanting.

Source of Information

• https:www.apsnet.org
• Crop production guide – Horticulture 2020.

Acknowledgement

• Dr.P.Renukadevi, Professor, Department of Plant Pathology, TNAU, Coimbatore. Photo courtesy, Dr.S.Vinodkumar
• Dr.N.Indra, Associate Professor, Department of Plant Pathology, TNAU, Coimbatore.