Wednesday, November 7, 2007 - 10:30 AM
266-5

Response to Selection for Turf Traits in Distichlis Spicata.

Dana Christensen, Anthony Koski, David Holm, Yaling Qian, James Detling, and Stephen Wallner. Colorado State University, 4300 E Co Rd 50, Ft Collins, CO 80524

Inland saltgrass, Distichlis spicata var. stricta (Torr.) Beetle, a native western U.S. grass, has potential in turf situations. Ecotypes display good color and high shoot density, even under drought stress, which turns blue grama, buffalograss, and bermudagrass brown. It also grows in saline conditions and tolerates reclaimed water. In a single cycle of selection we: Increased rust resistance about 20%, with a marked increase in resistant classes, and a marked decrease in susceptible classes. Realized heritability was .26 with significant year, and, year by line interaction. Decreased height by 1.3 inches with realized heritability of .33. Increased shoot density by almost 5 shoots per square inch, with a very strong heterotic response. Increased seed yield by 30% to a hand harvest yield of 18.1 gms per sq foot. Realized heritability was .36.

We also recorded strong associated responses while selecting for the above traits, in, spreading rate, which was heterotic, and, a shallower rhizome mass, which was uncorrelated on per plant basis with the decrease in above ground height, or increase in shoot density. Segregation of turf type was less pronounced when selection intensity was doubled. Doubling the selection intensity did not affect reproduction in terms of vegetative growth or seed yield.