Longitudinal and Radial Variability of Anatomical Properties, Fiber Morphology, and Mechanical Properties of Fibrovascular Bundle from Indonesian Arenga Longipes Mogea. Sp. Nov Frond

Figures & data

Figure 1. The illustration of section variability. (a) Longitudinal variation: (a1): bottom section, (a2): medium section, and (a3): upper section. (b) Radial variation: (b1): outer convex zone, (b2): middle zone, (b3): inner zone, and (b4): outer concave zone.

Figure 2. An illustration of area occupation measure of FVB. (a) Total transverse area; (b) Non-vascular tissue area;(c) Vascular tissue area.

Figure 3. An illustration of testing the FVB mechanical properties.

Figure 4. The Cross-section image of sugar palm frond (magnification 10×): a: sclerenchyma fiber; b: metaxylem vessel; c and d: parenchyma cell; e: phloem; f: sclerenchyma sheath protoxylem.

Figure 5. Cross-sectional image of frond upper, middle and bottom section: (a): outer convex zone, (b): outer concave zone, (c): middle zone, and (d): inner zone. Note: (1) is a representation of 4× magnification, and (2) is a representation of 10× magnification.

Table 1. The variability of anatomical and physical properties on bottom section of fronds.

Properties	Radial section (± SD)
	Outer		Middle	Inner
	Convex	Concave
Dimeter (µm)	52.39 ± 5.68	51.84 ± 6.06	51.52 ± 5.35	47.15 ± 4.79
Density (g/cm^3)	0.34 ± 0.07	0.34 ± 0.06	0.23 ± 0.03	0.18 ± 0.03
Number of fibrovascular bundles per 1 mm^2	3–4	3–4	1–2	1
Areas:
Total Transverse area of FVBs (mm^2)/TTA	0.66 ± 0.07	0.65 ± 0.08	0.65 ± 0.07	0.59 ± 0.06
Vascular tissue area of FVBs (mm^2)/VTA	0.10 ± 0.01	0.12 ± 0.03	0.42 ± 0.06	0.48 ± 0.05
Non-Vascular tissue area of FVBs (mm^2)/n-VTA	0.56 ± 0.07	0.53 ± 0.09	0.22 ± 0.03	0.11 ± 0.02
Ratio of VTA to TTA (%)	15.47 ± 2.25	18.55 ± 5.32	65.40 ± 3.93	81.93 ± 2.99
Ratio of n-VTA to TTA (%)	84.53 ± 2.25	81.45 ± 5.32	34.60 ± 3.93	18.07 ± 2.99

SD: standard deviation.

Table 2. The variability of anatomical and physical properties on middle section of frond.

Properties	Radial section (± SD)
	Outer		Middle	Inner
	Convex	Concave
Dimeter (µm)	49.63 ± 4.37	49.26 ± 3.47	49.17 ± 3.32	45.00 ± 4.56
Density (g/cm^3)	0.32 ± 0.03	0.32 ± 0.04	0.20 ± 0.02	0.18 ± 0.03
Number of fibrovascular bundles per 4 mm^2	3–4	3–4	1–2	1
Areas:
Total Transverse area of FVBs (mm^2)/TTA	0.62 ± 0.05	0.62 ± 0.04	0.62 ± 0.04	0.57 ± 0.06
Vascular tissue area of FVBs(mm^2)/VTA	0.10 ± 0.01	0.10 ± 0.01	0.43 ± 0.06	0.51 ± 0.05
Non-Vascular tissue area of FVBs (mm^2)/n-VTA	0.52 ± 0.05	0.52 ± 0.04	0.19 ± 0.06	0.06 ± 0.02
Ratio of VTA to TTA (%)	16.06 ± 1.74	16.15 ± 1.61	69.16 ± 8.53	89.68 ± 3.37
Ratio of n-VTA to TTA (%)	83.94 ± 1.74	83.85 ± 1.61	30.84 ± 8.53	10.32 ± 3.37

SD: standard deviation.

Table 3. The variability of anatomical and physical properties on upper section of fronds.

Properties	Radial section (± SD)
	Outer		Middle	Inner
	Convex	Concave
Diameter (µm)	48.78 ± 3.32	48.59 ± 4.60	48.22 ± 3.81	45.11 ± 3.89
Density (g/cm^3)	0.32 ± 0.04	0.32 ± 0.04	0.22 ± 0.02	0.14 ± 0.01
Number of fibrovascular bundles per 4 mm^2	3–4	3–4	1–2	1
Areas:
Total Transverse area of FVBs (mm^2)/TTA	0.61 ± 0.04	0.61 ± 0.06	0.61 ± 0.05	0.57 ± 0.05
Vascular tissue area (mm^2)/VTA	0.10 ± 0.01	0.10 ± 0.01	0.45 ± 0.06	0.49 ± 0.04
Non-Vascular tissue area (mm^2)/n-VTA	0.51 ± 0.04	0.51 ± 0.06	0.16 ± 0.07	0.07 ± 0.04
Ratio of VTA to TTA (%)	16.16 ± 1.59	16.26 ± 2.24	74.59 ± 10.08	87.21 ± 6.29
Ratio of n-VTA to TTA (%)	83.84 ± 1.59	83.74 ± 2.24	25.41 ± 10.08	12.70 ± 6.29

SD: standard deviation.

Figure 6. Histogram of longitudinal and radial variability of fiber morphology. a. Fiber length; b. Fiber diameter; c. Lumen diameter; and d. Fiber wall thickness. (Note: bar chart is representation of the standard deviation, means with the same letter are not significantly different from each other (P > 0.05 ANOVA followed by Duncan multiple range test).

Table 4. Fiber derivatives of FVB’s of A. longipes frond.

Radial Section	Slenderness ratio	Flexibility Coefficient	Runkel Ratio	Luce’s shape factor	Coefficient rigidity
Bottom section of frond (± SD)
Convex	86.00 ± 22.47	0.39 ± 0.07	1.68 ± 0.55	0.85 ± 0.05	0.31 ± 0.03
Concave	92.74 ± 24.14	0.41 ± 0.05	1.47 ± 0.33	0.83 ± 0.04	0.29 ± 0.02
Middle	83.63 ± 19.73	0.50 ± 0.01	0.99 ± 0.05	0.75 ± 0.01	0.25 ± 0.01
Inner	112.19 ± 20.66	0.48 ± 0.01	1.07 ± 0.05	0.76 ± 0.01	0.26 ± 0.01
Middle section of Frond (± SD)
Convex	95.22 ± 22.54	0.50 ± 0.02	0.99 ± 0.08	0.75 ± 0.02	0.25 ± 0.01
Concave	99.32 ± 24.15	0.51 ± 0.02	0.98 ± 0.08	0.74 ± 0.02	0.25 ± 0.01
Middle	83.90 ± 22.82	0.51 ± 0.02	0.96 ± 0.07	0.74 ± 0.02	0.24 ± 0.01
Inner	87.72 ± 17.19	0.50 ± 0.02	0.99 ± 0.05	0.75 ± 0.01	0.25 ± 0.01
Upper section of frond (± SD)
Convex	87.34 ± 31.16	0.54 ± 0.07	0.89 ± 0.22	0.71 ± 0.08	0.23 ± 0.01
Concave	99.99 ± 29.70	0.51 ± 0.03	0.97 ± 0.12	0.74 ± 0.03	0.25 ± 0.01
Middle	99.07 ± 29.15	0.51 ± 0.04	0.98 ± 0.16	0.74 ± 0.04	0.25 ± 0.02
Inner	80.03 ± 20.66	0.50 ± 0.01	0.99 ± 0.05	0.75 ± 0.01	0.25 ± 0.01

SD: standard deviation.

Figure 7. Histogram of longitudinal and radial variability of mechanical properties. a. tensile strength; and b. Young’s modulus. (Note: bar chart is representation of the standard deviation, Means with the same letter are not significantly different from each other (P > 0.05 ANOVA followed by Duncan multiple range test).

Figure 8. The relationships between density and mechanical properties (a. Tensile strength; b. Young’s modulus) as well as VTA:TTA ratio and mechanical properties (c. Tensile strength: d. Young’s modulus).