Resistance characterization of the genotype KS4202 to Aphis glycines Matsumura (Hemiptera: Aphididae)

Since its introduction in 2000, the soybean aphid (Aphis glycines Matsumura) represents a growing risk to soybean production throughout the United States. A viable alternative for reducing the economic damage caused by A. glycines is the use of host plant resistance. Pierson et al. (2010) first reported the reproductive stages of the soybean genotype KS4202 to be resistant to the soybean aphid. The objective of this study was to further characterize the resistance in KS4202 through a greenhouse study evaluating yield parameters at two soybean aphid infestation levels and three developmental stages. Soybeans plants were infested with aphids at the third node stage (V3), the fifth node stage (V5) and the beginning bloom stage (R1). Two levels infestation (10 and 20 aphids per plant) were applied to the respective developmental stages. The following yield parameters will be evaluated among control and aphid-infested plants: number of pods per plant, number of seeds per pod, average seed weight, average dry weight of pod, dry weight of stem, and total plant biomass. Results and conclusions will be presented.