The University of Arizona Yuma Ag Center researchers have conducted studies over the past years to better understand the population dynamics of several insect pests including Aphids in vegetables. Some of the aphid species that are found are green peach aphid (GPA, Myzus persicae) which was present in very high numbers this year, turnip aphid (Lipaphis erysimim), lettuce seed-stem aphid ( Acyrthosiphum lactucae), cabbage aphid (Brevicoryne brassicae) and Lettuce Aphid (Nasonovia ribis-nigri). Visitors at the research farm have expressed interest in how we collect this data. First we need to be able to identify the species of aphids present. To accomplish this, we recommend the ID tool published by Dr. Palumbo located at: http://ag.arizona.edu/crops/vegetables/advisories/docs/Aphids_Vegetables.pdf Then we count them one by one separating by species when the populations are low. When infestations of a dominant species are high, we estimate the area covered by 5 or 10 aphids, then extrapolate to estimate the total number per leaf. Finally these numbers are added obtaining the total on a plant. The number of plants sampled is variable. See a video demonstration of this procedure below:

Green Peach Aphid in Broccoli

To contact Marco Peña go to: marcop@ag.arizona.edu

For questions or comments on any of the topics please contact Marco Pena at the Yuma Agricultural Center.
College of Agriculture, The University of Arizona, Tucson, AZ.