Selected Soybean Plant Introductions with Partial Resistance to Sclerotinia sclerotiorum.

Sclerotinia stem rot, caused by Sclerotinia sclerotiorum, is a major soybean (Glycine max) disease in north-central regions of the United States and throughout the world. Current sources of resistance to Sclerotinia stem rot express partial resistance, and are limited in number within soybean germ plasm. A total of 6,520 maturity group (MG) 0 to IV plant introductions (PIs) were evaluated for Sclerotinia stem rot resistance in the United States and Canada in small plots or in the greenhouse from 1995 to 1997. Selected PIs with the most resistance were evaluated for resistance in the United States and Canada in replicated large plots from 1998 to 2000. The PIs in the MG I to III tests in Urbana, IL were evaluated for agronomic traits from 1998 to 2000. The selected PIs also were evaluated with an excised leaf inoculation and petiole inoculation technique. After the 1995 to 1997 evaluations, all but 68 PIs were eliminated because of their susceptibility to Sclerotinia stem rot. In field tests in Urbana, higher disease severity in selected MG I to III PIs was significantly (P< 0.05) associated with taller plant heights and greater canopy closure. All other agronomic traits evaluated were not associated or were inconsistently associated with disease severity. MG I to III PIs 153.282, 189.931, 196.157, 398.637, 417.201, 423.818, and 561.331 had high levels of resistance and had canopies similar to the resistant checks. The resistance ratings from the petiole inoculation technique had a high and significant (P< 0.01) correlation with disease severity in the MG I and II field tests. The partially resistant PIs identified in this study can be valuable in incorporating Sclerotinia stem rot resistance into elite germ plasm.

[1]  G. Hartman,et al.  Response of Ancestral Soybean Lines and Commercial Cultivars to Rhizoctonia Root and Hypocotyl Rot. , 2001, Plant disease.

[2]  S. Koenning,et al.  Soybean disease loss estimates for the United States from 1996 to 1998 , 2001 .

[3]  F. Workneh,et al.  Prevalence of sclerotinia stem rot of soybeans in the north-central United States in relation to tillage, climate, and latitudinal positions. , 2000, Phytopathology.

[4]  H. S. Kim,et al.  Reaction of Soybean Cultivars to Sclerotinia Stem Rot in Field, Greenhouse, and Laboratory Evaluations , 2000 .

[5]  H. S. Kim,et al.  Inheritance of Partial Resistance to Sclerotinia Stem Rot in Soybean , 2000 .

[6]  M. Risius,et al.  Environmental Sensitivity of Soybean Cultivar Response to Sclerotinia sclerotiorum. , 1999, Phytopathology.

[7]  X. Yang,et al.  Soybean Varietal Response and Yield Loss Caused by Sclerotinia sclerotiorum. , 1999, Plant disease.

[8]  C. Frampton,et al.  Genetic variation in New Zealand populations of the plant pathogen Sclerotinia sclerotiorum , 1999 .

[9]  H. S. Kim,et al.  Evaluation of soybean cultivars for resistance to Sclerotinia stem rot in field environments , 1999 .

[10]  S. Wegulo,et al.  Soybean Cultivar Responses to Sclerotinia sclerotiorum in Field and Controlled Environment Studies. , 1998, Plant disease.

[11]  C. D. Nickell,et al.  Yield and Seed Quality of Soybean Cultivars Infected with Sclerotinia sclerotiorum. , 1998, Plant disease.

[12]  C. D. Nickell,et al.  Response of Soybean Accessions from Provinces in Southern China to Phytophthora sojae. , 1998, Plant disease.

[13]  G. Hartman,et al.  Occurrence of Sclerotinia sclerotiorum in Soybean Fields in East-Central Illinois and Enumeration of Inocula in Soybean Seed Lots. , 1998, Plant disease.

[14]  C. D. Nickell,et al.  Brown Stem Rot Resistance in Soybean Germ Plasm from Central China. , 1997, Plant disease.

[15]  E. S. Oplinger,et al.  An Integrated Approach to Control Sclerotinia Stem Rot (White Mold) in Soybean , 1994 .

[16]  B. Doupnik.  SOYBEAN PRODUCTION AND DISEASE LOSS ESTIMATES FOR NORTH CENTRAL UNITED STATES FROM 1989 TO 1991 , 1993 .

[17]  B. Nelson,et al.  Effects of temperature and pathogen isolate on laboratory screening of soybean for resistance to Sclerotina sclerotiorum , 1991 .

[18]  B. Nelson,et al.  Comparison of laboratory and field evaluations of resistance in soybean to Sclerotinia sclerotiorum , 1991 .

[19]  G. Boland,et al.  Epidemiology of Sclerotinia stem rot of soybean in Ontario , 1988 .

[20]  T. Isleib,et al.  Laboratory and field assessment of resistance in soybean to stem rot caused by Sclerotinia sclerotiorum , 1987 .

[21]  GROWTHROOM EVALUATION OF SOYBEAN CULTIVARS FOR RESISTANCE TO Sclerotinia sclerotiorum , 1986 .

[22]  C. Grau,et al.  Effects of cultivars and cultural practices on Sclerotinia stem rot of soybean. , 1984 .

[23]  J. Steadman.  White mold -- a serious yield-limiting disease of bean. , 1983 .

[24]  C. Grau.  Resistance of Soybean Cultivars toSclerotinia sclerotiorum , 1982 .

[25]  C. Grau,et al.  Whetzelinia stem rot of soybean in Minnesota. , 1974 .

[26]  W. Fehr,et al.  Stage of Development Descriptions for Soybeans, Glycine Max (L.) Merrill , 1971 .

[27]  D. W. Chamberlain.  Sclerotinia stem rot of Soybeans. , 1951 .