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.
- 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 daytime
- The time of insecticide application is to be synchronised 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.
- TamilNadu Agritech Portal.