Vol. 10, Issue 10 (2021)

Author(s):
Smitha S Kumar, R Arulprakash, N Chitra and S Harish

Abstract:
Incidence of Phenacoccus manihoti was assessed in 37 locations of four major cassava growing districts of Tamil Nadu, viz., Salem, Namakkal, Coimbatore and Erode. In all the locations, adult female mealybugs as well as infested plant parts were collected from February to July 2021. Identification of P. manihoti was done after slide mounting adult females by following standard keys. In each location, P. manihoti infestation level and density were assessed as per the standard methodology. Variation in infestation of P. manihoti was observed during the study period. Of the 37 sampling locations, the infestation was higher in Pagalpatti I (96.5%) and lower in Kallupalayam II (7.4%). Higher mealybug density was noticed in four locations. P. manihoti infestation and density were higher during the month of April as well as in the cassava grown in rainfed condition. Also, infestation was lower in early planted cassava than in late planted ones. Among the cassava varieties, P. manihoti infestation was higher in Mulluvadi variety.