Skip to page content
USDA Forest Service

Research & Development Treesearch

Treesearch Home
About Treesearch
Contact Us
Research & Development
Forest Products Lab
International Institute of Tropical Forestry
Pacific Northwest
Pacific Southwest
Rocky Mountain
Southern Research Station
Help - We Participate  Government Made Easy

Global Forest Information Service

US Forest Service
P.O. Box 96090
Washington, D.C.

(202) 205-8333

You are here: Home / Search / Publication Information
Bookmark and Share

Publication Information

View PDF (519 KB bytes)

Title: A Strategy for the Third Breeding Cycle of Loblolly Pine in the Southeastern U.S.

Author: McKeand, S.E.; Bridgwater, F.E.;

Date: 1998

Source: Silvae Genetica 47, 4(1998)

Publication Series: Miscellaneous Publication

Description: A strategy for the North Carolina State University - Industry Cooperative Tree Improvement Program's third-cycle breeding for loblolly pine (Pinus taeda L.) was developed to provide genetic gain in the short-term as well as to maintain genetic diversity so that long-term genetic gains will also be possible. Our strategy will be to manage a hierarchy of three populations, each at a different level of intensity. The mainline population will consist of about 160 selections that are available to each cooperator in a given geographic region (i.e. recruitment population). These populations will be managed as subdivided breeding populations (40 sublines of 4 trees each) primarily to provide for long-term genetic gain and diversity The most intensively selected and managed hierarchy will be the elite populations. A highly selected group of trees (approximately 40 selections) will be managed to provide short-term genetic gain for each member's program. A third hierarchy will be the genetic diversity archives managed to preserve and breed genotypes with extreme breeding values for individual traits (not necessarily for all traits combined) as an insurance population for environmental or selection criteria changes in future generations. The improved efficiency of this breeding strategy along with the reduction in population sizes compared to the current program, will result in a substantial reduction in effort by individual cooperators. The increase in selection intensity from reducing the population sizes and the increased rate of breeding made possible by mating fewer trees will substantially increase gains in subsequent generations. While the most intensive effort will be devoted to those populations providing immediate genetic and financial gain, the long-term well-being of the genetic resource will be maintained by judicious management of all three hierarchies.

Keywords: Elite breeding populations, genetic gain, mating designs,

Publication Notes:

  • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
  • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
  • You may send email to to request a hard copy of this publication. (Please specify exactly which publication you are requesting and your mailing address.)



McKeand, S.E.; Bridgwater, F.E. 1998. A Strategy for the Third Breeding Cycle of Loblolly Pine in the Southeastern U.S. Silvae Genetica 47, 4(1998)


 [ Get Acrobat ]  Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility

USDA logo which links to the department's national site. Forest Service logo which links to the agency's national site.