SEED AGE-GERMINATION RELATIONSHIPS IN PLAINS ROUGH FESCUE, FESTUCA-ALTAICA SUBSPECIES HALLII

To test the relationship or germination with storage time seeds of sev en collections of Plains Rough Fescue (Festuca altaica Trin. subsp, ha llii [Vasey] Harms) ranging in age from 3 to 91 months were germinated at 10 and 20 degrees C in 0.0 or -0.69 MPa of water stress for 400 de gree-days, With the exception of one collection, total germination of all collections declined linearly as seeds aged. When seeds were 80 to 91 months of age germination was nearly nil. One collection apparentl y had an after-ripening requirement as germination increased initially as seeds aged, then declined. Degree-days to 50% of final germination increased linearly as seeds aged; across the seven collections about 1.2 to 1.9 more degree-days were required to reach 50% of final germin ation for each month of storage. Until optimal storage conditions are identified, Plains Rough. Fescue seeds should be sown the first or sec ond spring after harvest to take advantage of maximum seed vigor.