Abstract

Tapioca (Manihot utilissima) is an important root crop grown extensively in Kerala and Andhra States and in parts of South Arcot, Salem, Coimbatore, Chingelput and Tanjore districts of Madras State. Though widely grown in this State, there is no record of any insect pest damaging the crop. Fletcher (1917) and Subbiah Mudaliar (1951) have mentioned that this crop is free from any insect attack. But recently a scale-insect Aonidomytilus- albus, Okll., was noted attacking the crop in a severe form in parts of Salem, Pattukottai and Coimbatore. This scale is a pest of plants belonging to the genus Manihot in foreign contries viz. Africa, Florida, West Indies, Mexico, Formosa, Argentina, Brazil, etc. and is known there popularly as Cassava scale. The report on the first occurrence of this insect in pest form was received from Salem in the year 1951 and later reports of such occurrence are from Coimbatore, Tanjore, and South Arcot. At present the infestation is getting widespread throughout the State, wherever Tapioca is grown.

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