Diseases of fruit plantation medicinal and aromatic crops (2+1)

Banana burrowing nematode

Causal organism: Radopholus similis
Symptoms
Show yellowing of leaves and root discoloration, forms tunnels on suckers, followed by root decay and finally complete plant collapse.




Etiology

• Migratory endoparasite and obligate in nature.

Mode of spread and survival

• Primary source of inoculum: infected soil and suckers.
• Secondary source of inoculum: soil borne, water borne nematodes (2 stages).

Epidemiology

• High soil moisture and neutral pH, sandy loam soils and presence of susceptible host.

Life cycle

• The burrowing nematode has a migratory endoparasitic habit.
• Although the stages remain vermiform, sexual dimorphism is apparent with adult males being somewhat degenerated and probably non parasitic.
• Eggs are normally laid on infested tissues within 7-8 days at the rate of about 4 eggs/day.
• The life cycle from egg to egg stage takes 20-25 days at 24°c -25°c for its completion with eggs taking 8-10 days to hatch and larvae 10-13 days to mature.
• All the larval stages and female, except male are infective. They invade at any part of the root, causing more root damage and are capable of spending their entire life in the root.

Management

• Use disease free suckers collected from disease free area for plantation.
• Initially infected plants should be pulled out and burnt.
• Use disease resistant cultivars.
• Avoid excess nitrogen application in the soil
• Give proper dose of potassium after testing the soil
• Apply 5-10 kg of FYM at the root zone per plant.
• Application of carbofuran @ 10 -15 gm/plant with FYM and the application of neem cake @ 5kg/plant has also been found effective
• Paring pralinage treatment should be followed (Shaving the discoloured parts on rhizome and treating them with mud having Carbofuran granules).