Effects of Seeding Rate and Nitrogen Application on Tall Fescue Seed Production

Seeding rate and N fertilization are basic managements for tall fescue (Lolium arundinaceum Schreb.) seed production. Limited information is available on turf-and forage-type tall fescue responses of seed yield and yield components to seeding rate, N rate, N timing, and their interactions. We evaluated two seeding rates (3 and 9 kg ha(-1)), four N rates (90, 140, 190, and 240 kg ha(-1)), and two N timing treatments (one-third of the annual N applied in autumn+two-thirds applied the following spring and two-thirds of the annual N applied in autumn+one-third applied the following spring) on two tall fescue cultivars: Justice (a turf-type) and Dovey (a forage-type) for their effects on seed yield and yield components. Higher seed yields were obtained for turf-type Justice at the higher seeding rate of 9 kg ha(-1) or when more N was applied in autumn than in spring. Of the five seed-yield components, fertile tillers per square meter of both cultivars were most closely correlated with seed yield. Increasing N application rate or applying more N in autumn resulted in more fertile tillers. These results suggest that 3 kg ha(-1) is a sufficient seeding rate for high seed yield of forage-type tall fescues. Nitrogen rates and timing, however, need to be adjusted to types and cultivars; turf-type Justice required 190 kg N ha(-1) with two-thirds applied in autumn for highest seed yield whereas cultivar Dovey seed yield was optimized with 140 kg N ha(-1), without a signicant effect of N timing.