Scale Insect:

Causal organism: Melanaspis glomerata

• Waterlogging, high temperature and humidity favour build-up of scale insect population.
• Rainwater and high wind velocity facilitate dispersal of the pest.
• It spreads to new areas through seed material.
• Men and animals passing through the infested fields also lead to spread of the pest to the adjoining areas.
• The yield loss could range from negligible to total crop failure.

Symptoms

• Scales usually establish on internodes covered with leaf sheath.
• The leaves of infested canes show signs of tip drying and unhealthy pale green colour and with continued infestation these turn yellow.
• Desapping leads to non-opening of leaves also, which also turn yellow and finally dry up.
• Nodal region is more infested than internodal region.
• Infested crop losses its vigour, canes shrivel, growth is stunted and the internodal length is reduced drastically.
• Ultimately cane dries up. Such canes when slit open appear brownish red.