Rpp gene inheritance in soybean (Glycine max (L.) Merrill) for resistance to Asian rust

Abstract:

The four donors, SDP10 (Rpp 1, & Rpp 3), SDP18 (Rpp 2), SDP30 (Rpp2), and SDP36 (Rpp2), were crossed with the common susceptible female JS335 line of soybean. The goal of this experiment was to determine the inheritance of rust-resistant Rpp genes (Rpp1, Rpp 2, Rpp3) against Asian soybean rust. Because the F1 plants from the four crossings were resistant to rust, as researchers concluded that dominant genes are in charge of the rust resistance. The JS335 x SDP10 plants of the F2 generation were segregated in a ratio of 15 resistant: 1 susceptible and the BC1 F1 plants were separated in a ratio of 3 resistant: 1 susceptible, indicating the presence of duplicate gene interaction. The F2 offspring of the crosses JS335 x SDP18, JS335 x SDP30, and JS335 x SDP36 segregated in a 3 resistant: 1 susceptible ratio. However, in backcross (BC1 F1) generations, the test cross under the investigation was segregated in a 1 resistant: 1 susceptible ratio, suggesting that in these crosses, soybean rust resistance was governed by a dominant gene.