Xylem anatomical parameters of needles and axes of Picea abies
| 0 | 1 | 2 | n (0/1/2) |
Needles | | | | |
Needle area (mm[SUP]2[/SUP]) | 0.76±0.01 a | 0.63±0.02 b | 0.61±0.02 b | 5/5/2 |
Xylem area (μm[SUP]2[/SUP]) | 2288±102 a,b | 2200±80 a | 2521±99 b | 13/13/17 |
Tracheid diameter d (μm) | 3.81±0.13 a | 3.64±0.10 a | 3.70±0.10 a | 12/11/12 |
Hydraulic diameter d[SUB]h[/SUB] (μm) | 5.22±0.14 a | 5.19±0.14 a | 5.27±0.16 a | 12/11/12 |
Axes | | | | |
Tracheid diameter d (μm) | 6.40±0.35 a* | 7.25±0.38 a* | 7.03±0.39 a* | 4/5/4 |
Hydraulic diameter d[SUB]h[/SUB] (μm) | 8.61±0.34 a* | 9.87±0.35 a* | 10.12±0.47 a* | 4/5/4 |
- Mean cross-sectional areas of needles and needle xylem, mean tracheid diameter (d), and mean hydraulic diameter (d[SUB]h[/SUB]) of tracheids in needle and axes xylem are given. Columns show values of current year (0), 1-year-old (1), and 2-year-old (2) samples of needles and axes. Values of each line not followed by the same letter differ significantly. Significant differences inK[SUB]s[/SUB] between needles and axes xylem (within rows) are marked by asterisks. Mean ±SE. P ≤0.05. n=number of samples.
Temperature course of Picea abies needles during preparation and measurement with the new method. Times for arrangement and cooling of needles (A), addition of fluid Parablast (B), curing of the Parablast block (C), transfer to the ice-cooled water bath and sealing into the hydraulic system (D), and measurements (E) are indicated by the horizontal bar.
Hydraulic conductivities of the xylem in needles and axes of Picea abies
K[SUB]s[/SUB] (m[SUP]2[/SUP]×s[SUP]−1[/SUP]×MPa[SUP]−1[/SUP]×10[SUP]−4[/SUP]) | 0 | 1 | 2 | n (0/1/2) |
Needles | 4.23±0.64 a | 4.09±0.68 a,b | 2.18±0.43 b | 20/18/10 |
Axes | 4.82±0.57 a | 5.65±0.36 a | 4.86±0.74 a* | 6/9/8 |
- Specific hydraulic conductivity (K[SUB]s[/SUB], m[SUP]2[/SUP] s[SUP]−1[/SUP] MPa[SUP]−1[/SUP]×10[SUP]−4[/SUP]) of the xylem of current year (0), 1-year-old (1), and 2-year-old (2) samples of needles and axes. Values in each row not followed by the same letter differ significantly. Significant differences inK[SUB]S[/SUB] between needles and axes xylem (within rows) are marked by asterisks. Mean ±SE. P ≤ 0.05. n=number of samples.
Xylem anatomical parameters of needles and axes of Picea abies
| 0 | 1 | 2 | n (0/1/2) |
Needles | | | | |
Needle area (mm[SUP]2[/SUP]) | 0.76±0.01 a | 0.63±0.02 b | 0.61±0.02 b | 5/5/2 |
Xylem area (μm[SUP]2[/SUP]) | 2288±102 a,b | 2200±80 a | 2521±99 b | 13/13/17 |
Tracheid diameter d (μm) | 3.81±0.13 a | 3.64±0.10 a | 3.70±0.10 a | 12/11/12 |
Hydraulic diameter d[SUB]h[/SUB] (μm) | 5.22±0.14 a | 5.19±0.14 a | 5.27±0.16 a | 12/11/12 |
Axes | | | | |
Tracheid diameter d (μm) | 6.40±0.35 a* | 7.25±0.38 a* | 7.03±0.39 a* | 4/5/4 |
Hydraulic diameter d[SUB]h[/SUB] (μm) | 8.61±0.34 a* | 9.87±0.35 a* | 10.12±0.47 a* | 4/5/4 |
- Mean cross-sectional areas of needles and needle xylem, mean tracheid diameter (d), and mean hydraulic diameter (d[SUB]h[/SUB]) of tracheids in needle and axes xylem are given. Columns show values of current year (0), 1-year-old (1), and 2-year-old (2) samples of needles and axes. Values of each line not followed by the same letter differ significantly. Significant differences inK[SUB]s[/SUB] between needles and axes xylem (within rows) are marked by asterisks. Mean ±SE. P ≤0.05. n=number of samples.
Frequency distribution of conduit diameters in the xylem of needles of Picea abies. The relative number of conduits is given for 1 μm classes and shown for current year, 1-year-old, and 2-year old samples of needles (N0, N1, and N2).
Cross-sectional areas along needles of Picea abies. The mean cross-sectional areas of the whole needle, the area within the endodermis, and of the xylem are shown for 2 mm sections of ∼16 mm long current year (N0), 1-year-old (N1), and 2-year-old needles (N2). Mean SE is indicated on the left top of each panel. n=5.