Plassy Borer

Triệu chứng

The incidence of the borer can be easily recognized by the presence of dried crown of infested sugarcane. Primary infestation is caused by newly hatched larvae aggregating in the top three to five internodes, ranging between 50 to 180 larvae in a single stalk. Several bore holes are apparent in the top internodes. The affected stalks are full with red colored frass. The cane is hollow and dries up the central spindle and crown leaves and breaks more easily. Nodes adjacent to the infested internode develop sett roots which completely envelop the stalk; sprouting of nodal buds also occurs. In the case of secondary infestation, grownup larvae disperse to either the lower healthy portion of the canes showing primary attack on the neighboring canes.