Submitted to: South Dakota State University Extension Entomology Website
Publication Type: Popular Publication
Publication Acceptance Date: 2/2/2003
Publication Date: 2/12/2003
Citation: RIEDELL, W.E., CATANGUI, M., BECKENDORF, E.A. PRELIMINARY RESULTS OF CHINESE SOYBEAN APHID EXPERIMENTS. South Dakota State University Extension Entomology website. 2003. Interpretive Summary: The soybean aphid (Aphis glycines), an insect native of Asia, has rapidly invaded the northern U.S. soybean belt in past years. Last summer the explosive buildup of aphids led to severe yield losses and unanticipated insectide use in many states in the North Central U.S. Many growers and their advisors will be making aphid management decisions for the first time. Basic information on the soybean aphid and its damage to soybean is needed to help farmers decide on appropriate management options for this invasive pest.
Technical Abstract: A greenhouse experiment was conducted to determine how soybean yield and yield components react to infestations of Chinese soybean aphids. Plants were infested with aphids at the first node stage (V1), the third node stage (V3), the beginning bloom stage (R1), the full pod stage (R4) and the beginning maturity stage (R7). Aphids remained on the plants for a total of 600 aphid days (6000 aphid days is defined as 600 aphids present for 10 days) after which the insect pests were removed with insecticide. Infestation at the earlier stages of plant development reduced the number of seeds per plant while infestation at later stages of plant development reduced seed number as well as individual seed weight. Yield reductions of about 5 to 6 percent were seen in plants infested in the V1 and V3 stages while plants in the R4 and R7 stages had between 7 and 12 percent yield loss (respectively). We are in the process of analyzing the soybean seed obtained in this experiment for oil and protein levels. Additional studies in the greenhouse and field are also planned.