|Lygin, Anatoliy - UNIVERSITY OF ILLINOIS|
|Zernova, Olga - UNIVERSITY OF ILLINOIS|
|Lozovaya, Vera - UNIVERSITY OF ILLINOIS|
|Widholm, Jack - UNIVERSITY OF ILLINOIS|
Submitted to: Soybean Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 30, 2007
Publication Date: April 28, 2008
Citation: Li, S., Lygin, A., Zernova, O., Lozovaya, V., Hartman, G.L., Widholm, J.M. 2008. Genotype Response of Soybean (Glycine max) Whole Plants and Hairy Roots to Fusarium solani f. sp. glycines Infection. Soybean Science. 27:275-282. Interpretive Summary: Soybean sudden death syndrome (SDS), caused by a soilborne fungus (mold), is one of the most widespread and destructive fungal diseases of soybean. The response of 13 soybean genotypes to the pathogen infection was tested with potted greenhouse grown plants and with cultured hairy roots. Cultured hairy roots are commonly used for experimental purpose to measure biochemical and physiological effects. Both taproots of all soybean lines grown in the greenhouse and hairy roots had dark brown lesions following inoculation. While there was generally a correlation between the fungal growth on the cultured hairy roots and the whole plant symptoms of the different soybean lines, this was not always the case. The exceptions may be due to the fact that none of the soybean lines showed clear root resistance even though they may show toxin resistance that would result in fewer foliar symptoms.
Technical Abstract: Fusarium solani f. sp. Glycines, a soilborne fungus, infects soybean roots and causes sudden death syndrome. The response of 13 soybean genotypes to the pathogen infection was tested with potted greenhouse grown plants and with cultured hairy roots. The taproots of all genotypes grown plants measured 21 days after planting was greatest for Peking, followed by Spencer, Ripley, P3981, Williams 82, Essex, Forrest, Iroquois, PI 520733, Hartwig, PI 567650B, Jack, and PI 567374. There were significant negative correlations between foliar disease severity and shoot length, shoot weight, root weight, and total plant dry weights. The taproot lesion length was not correlated with foliar disease severity. When cultured hairy roots were inoculated with F. solani f. sp. glycines mycelial plugs, the colony diameters after 10 days were significantly (P = 0.05) different among soybean genotypes ranging from 17 to 40 mm. Fungal colony diameters on hairy roots of Spencer and Peking were greater (P = 0.05) than on PI 34 567374 and PI 520733. While there was generally a correlation between the growth of F. solani f. sp. glycines on the cultured hairy roots and the whole plant symptoms of the different genotypes, this was not always the case. The exceptions may be due to the fact that none of the genotypes showed clear root resistance even though they may show toxin resistance that would result in fewer foliar symptoms. Thus the soybean hairy root test system does not accurately measure soybean resistance to F. solani f. sp. glycine when measured by the foliar symptoms, but the hairy roots may be useful for screening for root resistance.