|SCIUMBATO, GABE - Mississippi State Extension Service|
Submitted to: Plant Disease Management Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/5/2011
Publication Date: 8/12/2011
Citation: Li, S., Sciumbato, G. 2011. Evaluation of maturity group IV soybean lines for resistance to purple seed stains in Mississippi 2010. Plant Disease Management Reports. 5:FC123.
Interpretive Summary: Purple seed stain (PSS) of soybean is an important disease that reduces seed quality and market grade and affects seed germination. In 2009, purple seed stain caused 6.4 million bushels of yield losses in 16 southern states. To identify new sources of resistance to purple seed stain, 14 maturity group IV soybean lines were tested and planted at Stoneville, MS on 25 May 2010. Some soybean lines were resistant and some were susceptible to purple seed stain. PI 346307 and PI 80479 were among the lines with lowest disease rating. These soybean lines may be used to reduce loss to this disease.
Technical Abstract: Purple seed stain (PSS) of soybean is an important disease caused by Cercospora kikuchii. PSS reduces seed quality and market grade, affects seed germination and vigor, and has been reported wherever soybeans are grown worldwide. In 2009, PSS caused 6.4 million bushels of yield losses in 16 southern states. To identify new sources of resistance to PSS, 14 maturity group IV soybean lines, originally from eight counties with different reactions to other diseases in previous trials, were screened in the field planted at Stoneville, MS on 25 May 2010. The experimental design was a randomized complete block with four replications. Seeds were harvested from each plot when the plants were mature. Seeds from each plot were tested for percent seed infection by C. kikuchii. Significant differences (P = 0.01) in seed infection by C. kikuchii were observed among soybean lines ranging from 3.0% to 16.5%. Soybean lines PI 346307 and PI 80479 were among the lines with lowest percentages of seed infection, while PI 58765 had the highest percentage of seed infection. Of 14 lines tested, five lines had less than 5% seed infection. These results will be confirmed in a replicated field trial in 2011.