Soybean Aphid Resistance in PI 243540 Is Controlled by a Single Dominant Gene

Abstract

The soybean aphid (Aphis glycines Matsumura) is a pest of soybean [Glycine max (L.) Merr.] in many soybean growing countries of the world. Host plant resistance is a very useful component of an integrated pest management program to control an insect problem. A maturity group (MG) IV plant introduction (PI) 243540 showed strong antibiosis resistance against the Ohio biotype of the soybean aphid. The objective of this study was to determine the inheritance of soybean aphid resistance gene(s) in PI 243540. The F1, F2, and F2‐derived F3 families from a cross between an aphid susceptible cultivar Wyandot and resistant PI 243540 were screened in a greenhouse with the Ohio biotype of the soybean aphid. All F1 plants were resistant to the soybean aphid and χ2 analysis of segregation of 341 F2 plants indicated a fit to a single dominant gene ratio of 3:1 (P = 0.51). Segregation in 330 F2:3 families fit an expected 1:2:1 ratio (P = 0.40). Our results indicate that a single dominant gene controls the soybean aphid resistance in PI 243540. The simple inheritance of this gene should be helpful to quickly transfer the gene to susceptible elite cultivars using the backcross breeding approach.