Liriomyza trifolii (Diptera: Agromyzidae) Suppression with Foliar Applications of Steinernema carpocapsae (Rhabditida: Steinernematidae) and Abamectin

A laboratory test of foliar application of infective-stage Steinernema carpocapsae (Weiser) (5 x lOS/ha) to chrysanthemums (Dendranthema morifolium (Ramat.)) infested with leafminer Liriomyza trifolii (Burgess) resulted in a mean leaf miner mortality of 64.2% attributable to nematode invasion. Subsequent foliar applications S. carpocapsae (5 x 108/ha) were compared with applications of abamectin (0.17 kg[AI]/ha) for control of leafminers infesting chrysanthemums grown in the greenhouse. After two applications of abamectin or nematodes, damage to and number of adults developing from sampled leaves were significantly reduced when compared with untreated foliage. The level of control achieved with nematodes was equivalent to that with abamectin. Environmental requirements for successful use of entomogenous nematodes for control of foliage-feeding pests are presented.