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Data from: Similarities among Test Sites Based on the Performance of Advanced Breeding Lines in the Great Plains Hard Winter Wheat Region

USDA-ARS coordinated regional wheat (Triticum aestivum L.) breeding trials examine agronomic performance and adaptation over a wider geographic range than single breeding programs can achieve. The trials provide an evaluation of experimental breeding lines in alternate test sites that are environmentally similar or dissimilar to the program of origin. Data from USDA-ARS Hard Winter Wheat Regional Nurseries grown in 1987 to 2014 were used to identify similarities among Great Plains test sites. Mean correlations of entry grain yields across locations and years were used in principal factor analyses to cluster them into production zones. The procedures used were identical to those of a previously published analysis using test data from 1959 to 1989. Five factors explained 67% of the variance in the correlation matrix among Southern Regional Performance Nursery (SRPN) locations. The analysis divided the SRPN into four major Great Plains production zones, designated Southeast, Northwest, Southwest and Northeast. The remaining minor production zone consisted of only two central South Dakota locations, both outside the typical target area and selection site of SRPN entries. In the Northern Regional Performance Nursery (NRPN), five production zones were established, with location separation predominantly resulting from east–west differences in performance. The SRPN and NRPN wheat production zones closely follow previously described ecological zones of adaptation of native Great Plains plant species. Wheat breeding programs and growers may continue to use the production zones established via the USDA-ARS coordinated winter wheat regional nurseries to target and select germplasm for crossing and for production.

Dataset Info

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Graybosch, Robert A.
Product Type
Spatial / Geographical Coverage Area
POLYGON ((-109.81274440885 49.014815923373, -109.81274440885 49.014815923373, -109.81274440885 49.014815923373))
POLYGON ((-109.98852565885 49.244859259717, -109.98852565885 49.244859259717, -109.98852565885 49.244859259717))
POLYGON ((-110.16430690885 49.014815923373, -97.508056908846 49.244859259717, -90.125244408846 32.81313219177, -101.90258815885 31.323610150998))
Spatial / Geographical Coverage Location
Great Plains region
Temporal Coverage
Intended Use
To use Southern Regional Performance Nursery (SRPN) and Northern Regional Performance Nursery (NRPN) data to evaluate correlations among the extant locations, to determine whether any changes have been observed in the clustering of test sites within production zones, and to establish whether breeders need to adjust target areas for both production and germplasm acquisition.
Crop Science
Contact Name
Graybosch, Robert A.
Contact Email
Public Access Level
Primary Article

Graybosch, R. A. (2017). Similarities among Test Sites Based on the Performance of Advanced Breeding Lines in the Great Plains Hard Winter Wheat Region. Crop Science, 57:1447-1454.

Funding Source(s)
Agricultural Research Service
Dataset DOI (digital object identifier)
Program Code
005:037 - Department of Agriculture - Research and Education
Bureau Code
005:18 - Agricultural Research Service
Modified Date
Release Date
Ag Data Commons Keywords: 
  • Plants & Crops
  • Crop production
  • Plants & Crops
  • Traits
  • Plants & Crops
  • Agroecosystems & Environment
  • Weather and Climate
  • Agroecosystems & Environment
  • Soil
  • Agroecosystems & Environment