Resistance to soybean aphid in early maturing plant introduction lines of soybean, 2012-2015

Authors: Hesler, Louis; Beckendorf, Eric; TILMON, K - The Ohio State University; BURKARD SCHULTZ, N - South Dakota State University; VAN DE STROET, B - South Dakota State University; ROZEBOOM, P - South Dakota State University

Submitted to: Arthropod Management Tests
Publication Type: Other
Publication Acceptance Date: 7/8/2017
Publication Date: 10/1/2017
Citation: Hesler, L.S., Beckendorf, E.A., Tilmon, K.J., Burkard Schultz, N., Van De Stroet, B.M., Rozeboom, P.A. 2017. Resistance to soybean aphid in early maturing plant introduction lines of soybean, 2012-2015. Arthropod Management Tests. 42(1): tsx112. https://doi.org/10.1093/amt/tsx112.
DOI: https://doi.org/10.1093/amt/tsx112

Interpretive Summary: Infestations by soybean aphid (SA) can reduce soybean yield. SA-resistant soybean may be useful in reducing infestations, limiting yield loss, and curbing insecticide use. One hundred twelve soybean lines were evaluated for SA resistance among nine laboratory tests. Soybean lines were assessed for resistance after 14 days of exposure to biotype 1 SA using a rating scale that progressed from 1 (50 SA or less per test plant) to 6 (250 SA or more per plant) in 50-aphid increments. Infestation ratings of 14 test lines did not differ from that of the aphid-resistant check; ratings of the other 98 lines were higher than that of the resistant check. Ratings for five of the 14 lines were lower than those of a susceptible check and did not differ those of the resistant check; ratings of another five test lines did not differ from those of either the resistant or susceptible checks. These 10 test lines had low overall ratings and may be candidates for more rigorous testing against SA. Ratings of the other four test lines did not differ from those of either resistant or susceptible checks, but had relatively high infestation ratings. The high ratings of the last four PI lines indicate considerable variability in SA resistance, and any advances for further testing should be based on careful selection of SA-resistant individuals within each line. Altogether, these results identified multiple sources that may be used in breeding SA-resistant soybeans.

Technical Abstract: Infestations by soybean aphid (SA) can reduce soybean yield. SA-resistant soybean may be useful in limiting infestations, preventing yield loss, and reducing insecticide use. In this study, a total of 112 soybean plant introduction (PI) lines was evaluated for SA resistance among nine growth-chamber tests. Resistance of PI lines were assessed 14 d after exposure to biotype 1 SA using a rating scale that progressed from 1 (0 to 50 SA per test plant) to 6 (>250 SA per plant) in 50-aphid increments. Infestation ratings of 14 PI lines did not differ from that of the resistant check; ratings of the other 98 lines were higher than that of the resistant check. For five of the 14 lines, ratings were lower than that of a susceptible check and did not differ from that of the resistant check; ratings of another five PI lines did not differ from those of both the resistant and susceptible checks. These 10 PI lines had median ratings =2.6, indicating a high proportion of resistant individuals within each of the lines, which may be advanced for more rigorous testing against SA. Ratings of the other four PI lines did not differ from those of either the resistant or susceptible checks, and their median infestation ratings were =4. These high median ratings indicate considerable variability in SA resistance and any advances for further testing should be based on careful selection of SA-resistant individuals within each PI line. Altogether, these results identified multiple sources that may be used in breeding SA-resistant soybeans.