The population dynamics of Thrips tabaci Lind. was evaluated for onion (Allium cepa) planted in July, August and September at the Ituporanga Experimental Station, EPAGRI S.A., Santa Catarina State, Brazil, from 1985 to 1988. For each planting date cv. Baia Periforme, Jubileu, EMPASC 351 Sel. Crioula and Norte 14 were used. Severe infestation in all cultivars was observed after mid-October. The population peak of T. tabaci occurred between the end of October and mid-November. Cultivars transplanted early tended to escape from high population densities. Populations of T. tabaci peaked during bulb formation and decreased thereafter.
Insecta; Thysanoptera; Allium cepa; population dynamics
