Abstract

During March-June 2012, cassava red mites, Oligonychus biharensis Hirst (Acari Tetranychidae) were found infesting grapevine at Orchard, Tamil Nadu Agricultural University, Coimbatore. This was the first record of this mite, Oligonychus biharensis infesting grapevine in India. The mite colonized mainly on the upper surface of the mature leaves and built large colonies. The infested leaves looked dusty due to the thin webs constructed by the mites. Initial feeding caused white spots which later coalesced to form large chlorotic patches. Later stages of symptoms included dark brown patches, crinkling, drying and subsequent defoliation of leaves. Biology of the mite in the laboratory, revealed the mean developmental time for an egg to become an adult was 11.8 days and the mean fecundity was 27.2 eggs per female during of June, 2012. This indicated the potential of this mite pest to breed several generations in a year and implied the probability of this pest to attain a major status in future, when conditions are favourable.

Keywords: O.biharensis, first record, alternate host, grapevine, Vitis vinifera