Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/11/2021
Publication Date: 3/24/2021
Citation: Bansal, R., Mian, R.M., Michel, A. 2021. Characterizing resistance to soybean aphid (Hemiptera: Aphididae): antibiosis and antixenosis assessment. Journal of Economic Entomology. 114(3):1329-1335. https://doi.org/10.1093/jee/toab038.
Interpretive Summary: The soybean aphid (SBA) is a major pest of soybean in North America and host plant resistance (HPR) is the most desirable approach to manage this pest. Presence of SBA biotypes capable of overcoming plant resistance diminishes the durability of HPR as a stable management tactic. Biotypes are different populations within an insect species that have differential responses to known HPR genes. To increase the durability of resistant cultivars, HPR needs to be deployed strategically. A complete understanding of HPR in existing resistant germplasm is a required for strategic deployment of HPR. In this study, we characterized the HPR in 11 soybean germplasm lines to determine antibiosis and antixenosis categories of resistance to different SBA biotypes. We found differences in manifestation of a particular resistance category in response to infestation by different biotypes. Overall, germplasm lines manifested resistance through both antibiosis and antixenosis. Soybean cultivars developed through breeding of resistance traits from studied PIs have the potential to delay the biotype evolution, thus, to increase the HPR durability.
Technical Abstract: Host-plant resistance (HPR) remains a vital tool to manage soybean aphid (Aphis glycines Matsumura), a major pest of soybean in Midwestern United States and southern Canada. HPR can be overcome by virulent biotypes of A. glycines; thus, in order to increase the durability of resistant cultivars, HPR needs to be deployed strategically. To improve the strategic deployment, a complete understanding of HPR in existing resistant germplasm will help ensure HPR success. In this study, we characterized HPR soybean to determine antibiosis and antixenosis categories of resistance to different biotypes of A. glycines. No-choice and free-choice tests were performed on 11 previously reported plant introductions (PIs) possessing resistance to at least one A. glycines biotype (1, 2, and 3). Overall, we found that the PIs manifested differences of a particular resistance category in response to infestation by different biotypes. Our data from no-choice tests indicate that all tested PIs possess antibiosis-based resistance to three biotypes. However, the strength of antibiosis was variable as some PIs showed stronger antibiosis toward a given biotype than others. All tested PIs manifested antixenosis, in addition to antibiosis. Furthermore, detached leaf assays revealed that resistance to A. glycines was not retained in excised soybean leaves. Characterization of resistance in this study can contribute to develop strategies for future deployment of resistant cultivars developed from these PIs.