Tuesday, November 6, 2007
171-17

Evaluation of Selfed and Open Pollinated Tall Fescue Progeny for Turf.

Keith Rincker, Southern Illinois University Carbondale, 20 Pineshore Dr. Apt. 9, Carbondale, IL 62902

Tall fescue, which normally reproduces by open pollination, has a degree of self-compatibility.  Self pollination can be used to produce progenies that have segregating alleles.  Selection against deleterious recessive alleles should therefore be more effective within S1 populations than from open pollinated (OP) populations.  The long-range objective of this study is to compare the genetic gain from selection within S1 and OP progenies from the same female parents.  In 2006, selfed and open pollinated progenies were obtained from seven parents out of attempts at selfing 16 parents within a polycross where the parents had been selected for disease resistance.  The progenies were transplanted to the field in the spring of 2007 into a randomized complete block design with four replications in two locations so that comparisons could be made between selfed and open pollinated progenies with the same female parent in common.  In the greenhouse, the length of the first leaf and rate of leaf production after tillering was measured to estimate seedling vigor and genetic vigor, respectively.  In the field, mature leaf length and width, plant spread, and number of seedheads were measured.  In the greenhouse three families were found to have smaller S1 seedlings, but there were no significant effects in the rate of leaf production.  One S1 family has longer mature leaves (OP= 17.1cm compared to S1= 22.5cm) while another S1 family has shorter leaves (OP= 19.5cm compared to S1= 17.0cm) and yet another S1 family had a larger mean number of seedheads (OP= 22.4 compared to S1= 36.8).