|ALLOATTI, JULIETA - University Of Arkansas|
|CHEN, PENGYIN - University Of Arkansas|
|ZENG, AILAN - University Of Arkansas|
|RUPE, JOHN - University Of Arkansas|
|FLOREZ-PALACIOS, LILANA - University Of Arkansas|
|ORAZALY, MOLDIR - University Of Arkansas|
Submitted to: Euphytica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/7/2015
Publication Date: 12/1/2015
Citation: Alloatti, J., Chen, P., Zeng, A., Li, S., Rupe, J., Florez-Palacios, L., Orazaly, M. 2015. Inheritance of and molecular markers for purple seed stain resistance in soybean. Euphytica. 206:701-709. doi: 10.1007/s10681-015-1492-2.
Interpretive Summary: Purple seed stain (PSS) is an important soybean disease causing poor seed quality. Use of genetic resistance is the most practical and economical way to control the disease. The objectives of this research were to investigate the inheritance of resistance to PSS and to identify molecular markers tightly linked to the candidate resistance gene. Two plant populations were developed by crossing PI80837 (resistant to purple seed stain) to AP350 and MO/PSD-0259 (both susceptible to purple seed stain). Our results confirm the presence of a candidate resistance gene in PI80837 and also indicate a second gene for resistance. The purple seed stain-resistant line and the resistance genes identified in this study will be valuable for breeders in developing resistant cultivars, and the molecular markers linked to the resistance gene will facilitate the selection of resistance in a breeding program.
Technical Abstract: Purple seed stain (PSS) caused by Cercospora kikuchii, is an important disease of soybean, causing seed quality deterioration. Use of genetic resistance is the most practical and economical way to control the disease. The objectives of this research were to investigate the inheritance of resistance to PSS and to identify SSR markers tightly linked to the candidate resistance gene Rpss1. Two plant populations were developed by crossing PI80837 (resistant to PSS) to AP350 and MO/PSD-0259 (both susceptible to PSS). F2:5 lines from each cross were grown at Kibler, AR in a randomized complete block design with three replications. Each plot was harvested and a seed sample was taken to evaluate percentage of visual PSS (% PSS) and percentage of C. kikuchii infection (% C. kikuchii). Range, LSMeans, and confidence intervals of the parents were used to classify resistant and susceptible reactions in the F2:5 lines for the two variables evaluated. Sixteen SSR markers in a 22.09 cM region on linkage group (LG) G were used to screen the parents and F2:5 lines for both populations. Significant differences in % PSS and % C. kikuchii were observed for the parents and F2:5 lines from both populations. For the two variables evaluated, both populations showed a good fit to a ratio of 15 resistant: 1 susceptible for two dominant genes. One chromosomal region in the vicinity of Satt115 and Satt340 on LG G was found to be associated with the resistance gene Rpss1 in both populations. These results confirm the presence of a candidate resistance gene Rpss1 in PI80837 and also indicate an additional putative gene for PSS resistance.