HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via ISI Web of Science (2) Citing Articles via Google Scholar Google Scholar Articles by Devine, T. E. Search for Related Content PubMed Articles by Devine, T. E. Agricola Articles by Devine, T. E.

Genetic Linkage Tests for the Rj4 Gene in Soybean

Plant Molecular Biology Lab, Plant Sciences Inst. USDA-ARS, Beltsville Agric. Res. Center-West, Beltsville, MD 20705-2350

^* Corresponding author.

The Rj4 allele in soybean, Glycine max (L.) Merr., conditions an ineffective nodulation response primarily with bradyrhizobial strains classified as Bradyrhizobium elkanii, which are less efficient in N₂ fixation with soybean, thus protecting the plant from many of these strains. The diminishing frequency of the RJ4 allele with agronomic selection poses the question of possible linkage with genes of negative agronomic selective value. Little is known of the linkage relationships of the Rj4 locus. This report analyzes genetic linkage tests of the Kj4 locus with 12 other loci: F, Frl, Fr2,1, LI, Ln, P, Wl, Y9, Y10, Y12, and YJ7. Segregating F₂ and F₃, progeny of several crosses were used to generate data for analysis. The Rj4 assays were conducted by planting seeds in sterile vermiculite and inoculating with broth cultures of strain USDA 61 from the Beltsville Rhizobium Culture Collection and examining the roots after 2 to 4 wk culture in the greenhouse. Other traits were scored either in the field or in the greenhouse. Chisquare was used to test for linkage, and the product method or method of maximum likelihood was used to estimate recombination. Only the Y17 locus showed evidence of genetic linkage with Rj4. The estimated recombination of Y17 and Rj4 was 46 ± 2%.

Received for publication September 3, 1991.