Non-Technical Summary

STRUCTURAL POLYMORPHISMS AS CAUSES OF HETEROSIS IN POPULUS

INVESTIGATORS: Steven H. Strauss, Stephen DiFazio, Brian Stanton, and Todd Rosenstiel

INSTITUTION: Oregon State University, West Virginia University, Greenwood Resources, Portland State University

NON-TECHNICAL SUMMARY:

Natural genetic diversity within and among species is the basis of most plant breeding programs. Breeding progress relies on variation in DNA sequences, but also on variability in the presence and absence of genes and DNA that control gene expression, which we together refer to as “structural polymorphisms” (SPs). The objectives of this project are to characterize the extent of SP between and within species in cottonwood trees that are used to produce wood and bioenergy, and examine their relationship to growth, stress tolerance, and breeding efficiency.

OBJECTIVES:

We will study wild black cottonwoods and interspecies hybrids important in plantations in the Pacific Northwest USA and other parts of the world. We will focus on the extent to which assay of SPs could improve hybrid breeding compared to alternative approaches, including the use of non-SP DNA sequence variation under newly developed “genomic selection” methods of advanced breeding. Our preliminary work has already demonstrated that SPs are abundant within and among species, and they are associated with phenotypic variation.

We will use phenotypic and/or genomic information from existing research trials and studies, and also generate substantial new phenotypic and genomic information. The Populus breeding program of GreenWood Resources (GWR), which leads in poplar breeding in the Pacific Northwest USA, will provide F1 hybrid genotypes and phenotypic information.

APPROACH:

Our project will seeks to answer the following questions:

1) What is the extent of within- and between-species variation in SPs?
2) Are SPs associated with variation in productivity, stability of growth among plantation environments, and temperature stresses?
3) Does knowledge of structural variation provide value beyond SNPs as part of molecular selection during hybrid breeding?

We have engaged collaborators who are internationally known scholars and practitioners. If successful, this project will lead to methods that can substantially increase the efficiency and rate of genetic improvement, providing economic and environmental benefits for growers and society.

PROJECT CONTACT:

Name: Strauss, S.H.
Phone: 541-737-6578
Fax: 541-737-1393
Email: