About Us | Help Videos | Contact Us | Subscriptions



This article in CS

  1. Vol. 39 No. 4, p. 1021-1025
    Received: Aug 3, 1998

    * Corresponding author(s): dweaver@acesag.auburn.edu
Request Permissions


Genetic Analysis of Frogeye Leaf Spot Resistance in PI54610 and Peking Soybean

  1. William A. Baker,
  2. David B. Weaver ,
  3. Jiansheng Qui and
  4. Patrick F. Pace
  1. D ep. of Plant Pathology, Auburn, AL 36849;
    D EKALB Genetics Corporation, 3100 Sycamore Road, DeKalb, IL 60115.



Frogeye leaf spot (FLS) of soybean [Glycine max (L.) Men.] is caused by the fungus Cercospora sojina Hara. The fungus is ubiquitous, but only problematic in hot humid soybean-producing regions such as Brazil, China, Nigeria, and the southern USA. Significant yield losses (10–50%) are commonly associated with FLS epidemics. The quantification of unique alleles for resistance within the southern germplasm pool is an essential step toward developing a more usable set of differential genotypes and thereby clarifying the race situation within the C. sojina-soybean interaction. Our objective was to determine the inheritance of resistance to FLS in PI54610 and Peking and their allelic relationship to Res,. ‘Lee’ soybean was used as a susceptible parent for crosses and control in all experiments. Parents and F2 seedlings were inoculated with a C. sojina spore suspension in the greenhouse or field and then rated for disease development 14 to 21 d later. On the basis of segregation ratios (3:1 resistant/susceptible in Peking × Lee and PI54610 × Lee, and 15:1 in ‘Davis’ × Peking and PI54610 × Peking), we found resistance in Peking was determined by a single dominant gene nonallelic to Rcs3. We also found, based on nonsegregation of resistance within the Davis × PI54610 population, that PI54610 has the same gene as in Davis (Rcs3). Resistance in Peking should be considered unique for the purpose of race differentiation and as a commercial source of resistance to FLS should Rcs3 fail.

Contribution from the Dep. of Agronomy and Soils, Auburn Univ., Auburn, AL 36849.

  Please view the pdf by using the Full Text (PDF) link under 'View' to the left.

Copyright © .