My Account: Log In | Join | Renew
Search
Author
Title
Vol.
Issue
Year
1st Page

Abstract

 

This article in CS

  1. Vol. 46 No. 1, p. 30-35
     
    Received: Dec 22, 2004
    Published: Jan, 2006


    * Corresponding author(s): rboerma@uga.edu
 View
 Download
 Alerts
 Permissions
 Share

doi:10.2135/cropsci2004.0750

Gametic Selection by Glyphosate in Soybean Plants Hemizygous for the CP4 EPSPS Transgene

  1. David R. Walkera,
  2. Alan K. Walkerb,
  3. E. Dale Wooda,
  4. Magda E. Bonet Taleverac,
  5. Francisco E. Fernandezc,
  6. Gina B. Rowana,
  7. Craig K. Mootsd,
  8. Richard A. Leitze,
  9. Phillip A. Owenf,
  10. W. Earl Baxtera,
  11. Joseph L. Heada and
  12. H. Roger Boerma *a
  1. a Dep. of Crop and Soil Sciences, Center for Applied Genetic Technologies, 111 Riverbend Road, Univ. of Georgia, Athens, GA 30602-6810
    b Monsanto Co., 3302 S.E. Convenience Blvd., Ankeny, IA 50021
    c Monsanto Co., 2229 Avenida Militar, Isabela, PR 00662
    d Monsanto Co., P.O. Box 410, State Route 48– Bldg. 2, Stonington, IL 62567
    e Monsanto Co., 703 E. Benton Street, Oxford, IN 47971
    f Monsanto Co., 9631 Hedden Road, Evansville, IN 47725

Abstract

Glyphosate application to glyphosate-tolerant soybean [Glycine max (L.) Merr.] cultivars expressing a CP4 EPSPS transgene has become the most common method of soybean weed control in the USA. The objectives of this research were (i) to determine whether atypical segregation ratios for glyphosate tolerance and glyphosate sensitivity in the progeny of hemizygous plants resulted from gametic selection caused by glyphosate applications, (ii) to investigate the effects of different glyphosate application rates and timing of application on segregation ratios, and (iii) to determine whether male gametes, female gametes, or both were sensitive to the levels of glyphosate used. Segregation for glyphosate tolerance in a no-glyphosate control treatment fit the expected 3:1 segregation ratio, indicating segregation of a single transgene. Glyphosate applications at three stages of plant development (V3, V3 + 2 to 3 wk, V3 + 3 to 4 wk) eliminated the glyphosate-sensitive phenotypic class irrespective of plant maturation stage in a field experiment. Variations observed in the relative proportions of lines with either all-tolerant or segregating phenotypic classes depended on glyphosate dosage and stage of plant development at the time of application. Overall, the data suggest that glyphosate application to hemizygous plants shortly before the onset of flowering was lethal to male gametes that do not carry the glyphosate tolerance transgene.

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

Copyright © 2006. Crop Science Society of AmericaCrop Science Society of America