Overview and Objectives - The Backcrossing Process

This lesson discusses the final stage of developing genetically engineered crops. The need for backcrossing, and the steps of this breeding method are described. Yield lag, yield drag, and gene stacking are also discussed. At the completion of this lesson you should be able to:

  • Explain why backcross breeding is necessary in developing genetically engineered lines.
  • Describe how backcross breeding is done.
  • Explain the advantages and disadvantages of using selectable markers, ELISA, and PCR in screening for transgenic plants.
  • Predict the amount of time it would take for a specific backcrossing program to be completed.
  • Distinguish between the concepts of yield lag and yield drag and describe the potential causes of each.
  • Define 'gene stacking' and list the two possible ways to stack genes.


Peer Reviewed Web Lesson JNRLSE Approved 2003

Development of this lesson was supported in part by Cooperative State Research, Education, & Extension Service, U.S. Dept of Agriculture under Agreement Number 98-EATP-1-0403 administered by Cornell University and the American Distance Education Consortium (ADEC). Any opinions, findings, conclusions or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.