Root grubs: Basilepta fulvicorne, Holotrichia serrata

• Among the three species B. fulvicorne is found to cause more damage in cardamom tracts.

Symptoms of damage:

• The grubs feed on the roots in the form of irregular scraping.
• In advanced stages entire root system is found damaged resulting in drying and rotting depending on the season of attack.
• In the severely infested plants, leaves turn yellow and dry.

Identification of pest:

• Grubs: Short, stout, 'C' shaped, pale white in colour.
• Adult: Beetles are shiny, metallic blue, bluish green, greenish brown or brown.

Management:

• Collect the beetles using hand nets during peak period of emergence i.e., during April-May and kill them.
• Beetles can be seen resting on the leaves during day time
• The time of insecticide application is to be synchronized with the emergence of adults and egg laying.
• Applying chlorpyriphos 0.075% or phorate 2-4 g a.i./plant in May and in September-October is effective in reducing the population of grubs.
• Light raking of soil before the insecticide application is essential for effective control of root grubs.

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