Elevated temperature differently affects foliar nitrogen partitioning in seedlings of diverse Douglas fir provenances

Foliar nitrogen metabolism of adult Douglas-fir trees is affected by soil water availability and varies little among provenances

The coniferous forest tree Douglas-fir (Pseudotsuga menziesii) is native to the pacific North America, and is increasingly planted in temperate regions worldwide. Nitrogen (N) metabolism is of great importance for growth, resistance and resilience of trees. In the present study, foliar N metabolism of adult trees of three coastal and one interior provenance of Douglas-fir grown at two common ga...

Relationships Between Needle Nitrogen Concentration and Photosynthetic Responses of Douglas-Fir Seedlings to Elevated CO2 and Temperature

Rate of Respiration of Douglas-Fir Seedlings

The rate of photorespiration of Douglas-fir seedlings was measured under different light intensities by: (1) extrapolating the curve for CO., uptake in reilation to atmospheric CO, content to zero CO2, content, and (2) measuring CO, evolution of the plants into a CO2-free airstream. Different results, obtained from these techniques, were lelieved to be caused by 'a severe restriction of the pho...

Growth and Foliar Nutrition of Douglas-Fir Seedlings Provided with Supplemental Polymer-Coated Fertilizer

Polymer-coated fertilizer (PCF) provides a potential means to optimize nutrient delivery for plant uptake, while minimizing leaching. Coating technology varies by manufacturer, which may alter patterns of nutrient release over time among comparable products. Three months following sowing, Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings were transplanted into containers with Osmocot...

Adaptive significance of intermittent shoot growth in Douglas-fir seedlings.

We tested the hypothesis that intermittent (lammas) shoot growth in Douglas-fir (Pseudotsuga menziesii var menziesii (Mirb.) Franco) seedlings from dry regions of southwest Oregon is adaptively significant. Seedlings from open-pollinated families (160 total) from two inland (dry) and two coastal (wet) sources were grown under either well-watered or intermittent drought conditions (temporary dro...