1a.Objectives (from AD-416):
1. Collect germplasm from diverse sites and ecological areas across the Great Basin.
2. Establish common gardens studies at contrasting sites, determine adaptive plant traits, and assess genetic variation across the landscape.
3. Using regression modeling, relate plant traits to environmental factors and develop seed transfer zones.
4. Conserve and distribute collected germplasm available through the Western Regional Plant Introduction Station seed repository and the National Plant Germplasm System.
1b.Approach (from AD-416):
Seeds collected from diverse areas in the Great Basin will be used in common garden studies at Central Ferry, WA, and either at Reno or Fallon NV, cooperative with University of Nevada and the Fallon Plant Material Center. Each garden will consist of seeds collected from at least 100 diverse locations. For each location there will be two families represented in a randomized block design with 6 replications. This will result in 1200 to 1800 plants per site per species. Numerous traits describing plant growth and devleopment will be measured on each plant. Analyses of variance will be conducted for each trait to determine seed source variation. Previous work with Mountain Brome, Tapertip onion, Bluegbunch wheatgrass and Indian ricegrass all show strong genetic variation across the landscape. So this result is expected for most species and suggests differences in adaptation to local environments. Principal components will be used with regression analysis to model the relationship between plant traits and local environmental factors such as precipitation, temperature and elevation. This will provide the basis for mapping seed adaptation zones.
This progress contributes to the Objective 2 of the parental project: “Conduct genetic characterizations and phenotypic evaluations of genetic resources of the preceding crops and related wild species for priority genetic and agronomic traits”. Collection and evaluation is continuing for numerous native rangeland species important to wildlife habitat and grazing and in the Great Basin. These include Sandberg bluegrass, Basin wildrye , Thurbers' needlegrass and Bottlebrush squirreltail. Substantial collections of these species has been completed and common gardens established for plant evaluation and seed zone development. For Sandberg bluegrass, two years data at three sites has been collected and initial analyses of variation completed on 15 plant traits representing more than 100 collection locations in the Great Basin and adjacent regions. There was widespread genetic variation among plant traits associated with different climates across the region which should allow development of seed zones. For Basin wildrye the final of three years of data collection at two common garden sites will be completed in 2013. Ploidy can have a substantial effect on adaptation and analysis of 113 Basin wildrye collections revealed plants from 55 locations were tetraploids and plants from 58 were octoploids. The first year of evaluation data was collected for Bottlebrush squirreltail and Thurbers' needlegrass on 12 plant traits. A taxonomic assessment of the Bottlebrush squirreltail collection revealed several species were included in the common gardens but the majority of accessions were the target species. Data for all the study species will be used to determine the interactions between genetic variation and climate across the collection region, and for developing seed zones needed for restoration.