First report of the blue alfalfa aphid (Homoptera: Aphididae) in Maryland: natural enemies and biotype.
Acyrthosiphon kondoi is reported for the 1st time in Maryland. A number of natural enemies associated with A. pisum were observed attacking A. kondoi, including Coleomegilla maculata, Adalia bipunctata, Chilocorus stigma and Coccinella septempunctata. A biotype test indicated that the alfalfa [lucerne] cultivars OK 51 and CUF-101 were tolerant to the aphid population, while Arc and PA-1 were not. WL-320, a common cultivar adapted for the mid-Atlantic states, was intermediate in tolerance.