The mealy bug Pseudococcus comstocki (Kuwana, 1902) population dynamics and preferential feeding on purple nutsedge (Cyperus rotundus) accessions grown in three locations (Lavras, Lambari and Três Pontas) in the southern region of Minas Gerais state, Brazil, were studied from March 1996 to March 1997. Mealy bug infested purple nutsedge all over the year at different intensities. The lowest infestation was observed in Lambari, and in Lavras and Três Pontas was observed similar mealy bug infestation levels. Air temperature and relative humidity were climatic variables that mostly influenced the insect infestation. It was also observed that mealy bug preferred feeding nutsedge grown in Lavras and Três Pontas.
weed; Pseudococcus comstocki; host plant resistance
