Monday, November 13, 2006

Phenotypic Variation of Saltgrass Accessions Relative to Geographic and Climatic Factors.

Hrvoje Rukavina, Colorado State University Dept. Horticulture, Shepardson Bldg., Shepardson Bldg., Fort Collins, CO 80523-1173, Randy Johnson, USDA Forest Service, Pacific Nortwest Research Station, Forestry Sciences Laboratory, Corvallis, OR 97331, and Harrison Hughes, Colorado State University, Dept. Horticulture, Shepardson Bldg, Fort Collins, CO 80523.

Breeding of a new turfgrass species requires an evaluation of numerous traits as well as an understanding of environmental factors influencing those traits. This study was therefore initiated to characterize variation in morphological traits and time of leaf browning in fall among 53 saltgrass clones from 42 locations relative to geographical and climatic variables at location of clones’ origin. Principle component analysis on the morphological traits extracted the first principle component (PC-1) that explained 78% of the variability. Regression analysis of PC-1 indicated that variation in growth traits was related to seasonal climatic variables summer drying and fall cooling. These explained ~ 50% of variability in morphological traits in two-variable regression model. Variation in time of leaf browning in fall (cold hardiness) appeared to be related to longitude and minimum winter temperature. Longitude and February minimum temperature explained 60% of total variability in the two-variable regression model. An understanding of the origin of specific saltgrass accession may facilitate selection for the specific trait of interest.    

Handout (.ppt format, 1226.0 kb)