Stems and leaf midribs are covered by circular, brown or greyish-black scales. Leaves of infested canes dry up at the tip, with an unhealthy pale green colour. The leaves later turn yellow with a continued infestation. The loss of sap also leads to the non-opening of the leaves, which ultimately turn yellow and dry up. Eventually, the cane dries up and appears brownish-red when slit opens. Infested canes become shriveled and the entire cane is covered with the pest forming encrustation on the stem in case of severe infestation. Due to its sedentary habits and minute size, the insect escapes the notice of the cane grower. Its existence is only revealed after severe damage has occurred.
Damage is caused by the crawler's scales. Females are ovoviviparous - which means that the young ones are produced by eggs that are hatched within the body of the female. Upon hatching, the crawlers (young immature scales) wander about in search of a feeding site. They attach their needle-like mouthparts, extract the plant sap and do not move again. The infestation begins with the formation of the internodes and continues to increase as the cane plant grows. Plant sap is sucked by crawlers. In severe infestation, the leaf sheath, lamina, and midrib are also infested.
Dip the setts in 1% fish oil rosin soap emulsion. Spray white oils (foliage and stalks), which show some effectiveness against young scales. Release Chilocorus nigritus or Pharascymnus horni egg card @ 5CC/AC. Introduce hymenopteran parasitoids such as Anabrotepis mayurai, Cheiloneurus sp. and predatory mites such as Saniosulus nudus and Tyrophagus putrescentiae, which can feed on the insect scale.
Always consider an integrated approach with preventive measures together with biological treatments, if available. Soak setts in 0.1% of malathion solution before planting. Spray dimethoate @ 2ml/l or monocrotophos @ 1.6m/l after detrashing. Treat setts with acephate 75 SP @ 1g/l twice after detrashing, just before the initial appearance of the pest.