Effect of Water-Spray Cooling Treatment in a Douglas-fir Seed Orchard on Seed Germination

1990

S. 137-146

1 Abb., 2 Tab., 24 Lit. Ang.

Unselbständiges Werk

200102069

Overhead-cooling treatment used to delay flowering produced non-significant effects on germination capacity, germination rate, germination value, and abnormal germination of seeds from a 13-year-old Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedling seed orchard. The percentage of variation accounted for by cooling treatment ranged from 0.0 to 1.0%. In contrast, variation among trees within treatments ranged from 28 to 46%. These effects were significant, indicating that each tree has an individual germination pattern. The temporal delay of reproductive phenology caused by temperature manipulation as a result of the cooling treatment was judged to be within the species' biological limits.