Figures (3)  Tables (7)
    • Figure 1. 

      Geographic origins of the 10 N. cadamba provenances (black dots) and location of the test site (red dot).

    • Figure 2. 

      Power contour-trend surfaces for (a) diameter breast height (DBH), (b) height (H), (c) volume (V), (d) wood basic density (WBD), and (e) vessel length/vessel diameter (VL/VD) of N. cadamba. The surface represents geographic variation, and the lines on the surface represent contours.

    • Figure 3. 

      Selection of superior provenances for wood products (a) and pulpwood (b).

    • TraitProvenanceMeanMinimumMaximumCV (%)
      DBH (cm)GXLZ12.92 ± 0.52ab4.1020.8028.88
      GXFCG13.31 ± 0.45a7.0020.9024.74
      GXNN13.26 ± 0.52a4.4020.1028.84
      GDGZ11.41 ± 0.49b5.6019.3028.07
      GDYF12.03 ± 0.56ab4.8020.1030.12
      YNBS11.66 ± 0.50ab4.2017.8027.86
      YNDH12.20 ± 0.54ab3.9019.8031.54
      YNJH13.22 ± 0.44a6.5018.2021.94
      YNMS13.01 ± 0.47ab5.7020.8026.00
      YNMN12.14 ± 0.55ab5.2019.7029.86
      H (m)GXLZ12.01 ± 0.54abcd1.0019.0032.22
      GXFCG12.98 ± 0.44ab7.0019.5024.79
      GXNN13.09 ± 0.46a6.0019.0025.64
      GDGZ10.91 ± 0.51d4.0017.3030.44
      GDYF11.28 ± 0.52cd5.0017.0029.91
      YNBS11.29 ± 0.56cd5.0018.0032.74
      YNDH11.91 ± 0.53abcd4.0019.0031.75
      YNJH12.78 ± 0.46abc7.0018.0023.64
      YNMS12.12 ± 0.48abcd5.0018.0028.60
      YNMN11.43 ± 0.53bcd5.0018.0030.81
      V (m3)GXLZ0.0907 ± 0.0096ab0.00250.303375.40
      GXFCG0.0991 ± 0.0091a0.01270.314367.23
      GXNN0.1022 ± 0.0095a0.00430.283368.04
      GDGZ0.0647 ± 0.0078b0.00580.237878.95
      GDYF0.0745 ± 0.0085ab0.00430.223673.91
      YNBS0.0695 ± 0.0080b0.00400.210475.09
      YNDH0.0833 ± 0.0094ab0.00220.250480.04
      YNJH0.0930 ± 0.0083ab0.01090.212858.79
      YNMS0.0890 ± 0.0079ab0.00600.224964.20
      YNMN0.0784 ± 0.0096ab0.00600.229181.63
      H, height; DBH, diameter at breast height; V, volume; CV, coefficient of variation. In column three, values within a trait that share lowercase superscripts are not significantly different according to Duncan's multiple range test (p = 0.05).

      Table 1. 

      Comparison of growth traits among provenances of N. cadamba.

    • TraitProvenanceMeanMinimumMaximumCV (%)
      FL (μm)GXLZ1,525.52 ± 21.43a1,442.721,635.323.97
      GXFCG1,459.09 ± 45.27a1,191.381,630.819.81
      GXNN1,432.45 ± 23.75ab1,334.341,555.945.50
      GDGZ1,411.77 ± 38.03ab1,127.741547.699.33
      GDYF1,303.55 ± 70.03b1,152.661,428.2710.74
      YNBS1,450.56 ± 35.81a1,072.861,692.2811.84
      YNDH1,415.46 ± 24.41ab1180.881,619.338.27
      YNJH1,398.71 ± 21.27ab1,100.281,661.149.86
      YNMS1,403.86 ± 34.67ab1,259.071,554.066.98
      YNMN1,428.68 ± 31.09ab1,184.371,618.108.70
      FD (μm)GXLZ32.99 ± 0.40a30.8634.263.47
      GXFCG32.11 ± 0.44ab29.1133.394.29
      GXNN32.65 ± 0.28a31.5134.562.80
      GDGZ32.60 ± 0.38a29.6134.244.08
      GDYF31.35 ± 0.35b30.3632.022.25
      YNBS32.31 ± 0.32ab28.4535.854.73
      YNDH32.57 ± 0.21a30.5434.273.03
      YNJH32.38 ± 0.18ab28.6634.203.67
      YNMS31.96 ± 0.35ab30.2432.973.14
      YNMN32.30 ± 0.25ab30.3033.843.11
      FL/FDGXLZ46.27 ± 0.72a44.1850.274.40
      GXFCG45.37 ± 0.98a40.9348.856.81
      GXNN43.87 ± 0.57ab41.8447.784.30
      GDGZ43.23 ± 0.74ab36.9645.735.94
      GDYF41.53 ± 1.89b37.9744.999.10
      YNBS44.77 ± 0.77a37.7149.418.24
      YNDH43.42 ± 0.59ab37.5050.066.55
      YNJH43.15 ± 0.54ab36.9850.558.15
      YNMS43.90 ± 0.78ab40.9647.385.00
      YNMN44.22 ± 0.86ab37.1650.987.82
      VL (μm)GXLZ696.34 ± 33.29a572.87873.2813.52
      GXFCG656.88 ± 26.47ab522.80802.9012.74
      GXNN601.42 ± 20.41b521.48732.2511.26
      GDGZ643.94 ± 19.49ab551.55748.0910.48
      GDYF676.82 ± 60.44ab549.34823.6317.86
      YNBS691.06 ± 20.35a547.53875.9814.12
      YNDH651.15 ± 23.54ab491.42866.5117.34
      YNJH659.95 ± 12.82ab532.67833.1812.59
      YNMS654.00 ± 26.61ab550.01787.4911.51
      YNMN639.87 ± 16.40ab551.43822.2110.25
      VD (μm)GXLZ176.31 ± 5.97a151.27195.299.58
      GXFCG164.43 ± 9.94ab108.29207.5119.11
      GXNN165.83 ± 6.23ab140.70203.9412.46
      GDGZ168.49 ± 10.19ab120.39243.9620.95
      GDYF144.87 ± 12.75b118.55177.2717.60
      YNBS158.96 ± 5.95ab107.95226.6817.97
      YNDH162.25 ± 6.13ab111.55231.3018.11
      YNJH160.13 ± 3.27ab99.36193.5713.25
      YNMS157.31 ± 7.60ab120.70176.6613.67
      YNMN165.72 ± 5.31ab129.60213.9312.81
      VL/VDGXLZ3.95 ± 0.12bc3.574.608.73
      GXFCG4.06 ± 0.15bc3.564.8311.75
      GXNN3.65 ± 0.12c3.064.5010.81
      GDGZ3.93 ± 0.19bc2.864.9016.33
      GDYF4.68 ± 0.21a4.165.178.90
      YNBS4.41 ± 0.11ab3.525.6412.43
      YNDH4.08 ± 0.15bc3.285.6817.72
      YNJH4.16 ± 0.09abc3.105.6313.27
      YNMS4.22 ± 0.24ab3.125.1915.88
      YNMN3.89 ± 0.10bc3.334.7710.07
      WBD (g/cm3)GXLZ0.3275 ± 0.0101bc0.28860.37828.74
      GXFCG0.3389 ± 0.0099abc0.28780.38969.20
      GXNN0.3274 ± 0.0081bc0.29800.38208.21
      GDGZ0.3457 ± 0.0067abc0.31880.39006.69
      GDYF0.3435 ± 0.0160abc0.31460.38929.31
      YNBS0.3600 ± 0.0046a0.33020.41286.15
      YNDH0.3253 ± 0.0048c0.26560.36607.13
      YNJH0.3381 ± 0.0042abc0.29600.39588.14
      YNMS0.3533 ± 0.0085ab0.32520.38726.83
      YNMN0.3298 ± 0.0092bc0.26060.400011.13
      Cr (%)GXLZ50.24 ± 0.89a47.953.965.04
      GXFCG50.15 ± 0.45a47.4451.812.87
      GXNN52.17 ± 0.70a47.8456.364.43
      GDGZ50.62 ± 0.85a45.1755.385.80
      GDYF51.19 ± 0.62a49.8752.772.43
      YNBS51.90 ± 0.67a45.9155.796.22
      YNDH51.87 ± 0.47a47.9358.234.33
      YNJH52.10 ± 0.47a40.9561.115.87
      YNMS52.62 ± 0.84a50.0557.394.50
      YNMN50.63 ± 0.76a45.7356.016.00
      FL, fiber length; FD, fiber diameter; FL/FD, the ratio of FL to FD; VL, vessel length; VD, vessel diameter; VL/VD, the ratio of VL to VD; WBD, wood basic density; Cr, Degree of crystallinity; CV, coefficient of variation. In column three, values within a trait that share lowercase superscripts are not significantly different according to Duncan’s multiple range test (p = 0.05).

      Table 2. 

      Comparison of wood properties among provenances of N. cadamba.

    • TraitVP
      (SE)
      VPB
      (SE)
      Ve
      (SE)
      h2CVG (%)
      DBH0.47
      (0.22)
      0.08
      (0.07)
      8.97
      (0.32)
      0.675.46
      H0.23
      (0.14)
      0.26
      (0.10)
      5.46
      (0.19)
      0.594.00
      V9.98e−05
      (5.91e−05)
      3.39e−05
      (2.64e−05)
      2.17e−03
      (7.85e−05)
      0.6411.83
      FL69.50
      (533.00)
      NE17,595.30
      (2037.00)
      0.020.59
      FD0.00
      (0.03)
      NE1.41
      (0.16)
      NENE
      FL/FD0.31
      (0.46)
      NE10.03
      (1.16)
      0.161.26
      VL94.03
      (277.50)
      NE7,771.29
      (900.80)
      0.071.48
      VD0.00
      (17.78)
      NE644.00
      (74.50)
      NENE
      VL/VD3.52e−02
      (2.81e−02)
      NE0.31
      (0.03)
      0.404.57
      WBD1.01e−04
      (7.48e−05)
      NE7.35e−04
      (8.56e−05)
      0.452.96
      Cr0.16
      (0.31)
      NE7.61
      (0.88)
      0.110.78
      H, height; DBH, diameter at breast height; V, volume; FL, fiber length; FD, fiber diameter; FL/FD, the ratio of FL to FD; VL, vessel length; VD, vessel diameter; VL/VD, the ratio of VL to VD; WBD, wood basic density; Cr, degree of crystallinity; VP, provenance variance; VPB, provenance by block interaction variance; Ve, random error variance; h2, provenance heritability; CVG genetic variation coefficient; SE, standard error. NE, not estimated and assumed to be zero.

      Table 3. 

      Variance components, provenance heritabilities, and genetic variation coefficients among the provenances.

    • DBH
      (SE)
      H
      (SE)
      V
      (SE)
      FL
      (SE)
      FD
      (SE)
      FL/FD
      (SE)
      VL
      (SE)
      VD
      (SE)
      VL/VD
      (SE)
      WBD
      (SE)
      Cr
      (SE)
      DBH0.97
      (0.01)
      0.99
      (0.01)
      −0.07
      (0.27)
      NE−0.21
      (0.69)
      −0.22
      (0.24)
      NE−0.05
      (0.15)
      −0.17
      (0.16)
      −0.02
      (0.42)
      H0.87
      (0.01)
      0.97
      (0.02)
      0.10
      (0.37)
      NE0.01
      (0.19)
      −0.18
      (0.26)
      NE−0.03
      (0.12)
      −0.16
      (0.12)
      −0.02
      (0.34)
      V0.98
      (0.01)
      0.91
      (0.05)
      −0.09
      (0.19)
      NE−0.15
      (0.39)
      −0.15
      (0.30)
      NE−0.02
      (0.13)
      −0.18
      (0.15)
      −0.03
      (0.41)
      FL0.34
      (0.07)
      0.39
      (0.07)
      0.36
      (0.07)
      NE0.99
      (0.01)
      0.58
      (0.82)
      NE0.17
      (0.22)
      0.01
      (0.45)
      −0.14
      (0.17)
      FD0.32
      (0.07)
      0.32
      (0.07)
      0.30
      (0.07)
      0.71
      (0.04)
      NENENENENENE
      FL/FD0.28
      (0.08)
      0.34
      (0.07)
      0.30
      (0.07)
      0.99
      (0.01)
      0.41
      (0.07)
      −0.02
      (0.58)
      NE0.17
      (0.83)
      0.46
      (0.79)
      −0.41
      (0.68)
      VL0.17
      (0.08)
      0.18
      (0.08)
      0.16
      (0.08)
      0.60
      (0.05)
      0.70
      (0.10)
      0.51
      (0.06)
      NE0.66
      (0.01)
      0.44
      (0.56)
      0.09
      (0.69)
      VD0.41
      (0.07)
      0.39
      (0.07)
      0.38
      (0.07)
      0.70
      (0.04)
      0.99
      (0.07)
      0.56
      (0.06)
      0.47
      (0.23)
      NENENE
      VL/VD−0.35
      (0.07)
      −0.31
      (0.09)
      −0.31
      (0.08)
      −0.28
      (0.08)
      −0.53
      (0.10)
      −0.20
      (0.08)
      0.57
      (0.16)
      −0.66
      (0.05)
      0.02
      (0.19)
      0.87
      (0.82)
      WBD−0.12
      (0.08)
      −0.11
      (0.08)
      −0.10
      (0.08)
      −0.14
      (0.08)
      −0.52
      (0.10)
      −0.02
      (0.08)
      −0.99
      (0.86)
      −0.28
      (0.07)
      0.20
      (0.09)
      0.29
      (0.81)
      Cr−0.12
      (0.08)
      −0.08
      (0.08)
      −0.07
      (0.08)
      −0.02
      (0.12)
      −0.06
      (0.08)
      0.02
      (0.12)
      0.07
      (0.08)
      −0.15
      (0.12)
      0.18
      (0.08)
      0.14
      (0.08)
      Above the diagonal are genetic correlations, and below the diagonal are phenotypic correlations. H, height; DBH, diameter at breast height; V, volume; FL, fiber length; FD, fiber diameter; FL/FD, the ratio of FL to FD; VL, vessel length; VD, vessel diameter; VL/VD, the ratio of VL to VD; WBD, wood basic density; Cr, degree of crystallinity; SE, Standard error. NE, not estimated and assumed to be zero.

      Table 4. 

      Genetic (rg) and phenotypic (rP) correlations between all studied traits.

    • TraitRegression equation of trend surface analysisFitting coefficientp-value
      DBHZ = −393.1 + 14.85x + 4.574y − 0.3657x2 − 0.02434y2 + 0.01936xy0.01957.34e−07
      HZ = −169.6 + 7.012x + 1.971y−0.2409x2− 0.01412y2 + 0.04008xy0.01531.68e−05
      VZ = −5.54 + 0.2083x + 0.06306y − 0.004804x2 − 0.0003198y2 + 0.0001185xy0.01714.73e−06
      FLZ = −16750 + 145.6x + 309.1y − 7.195x2 − 1.695y2 + 2.044xy0.04090.2709
      FDZ = 76.805095 − 2.054393x − 0.447867y − 0.099681x2 − 0.005207y2 + 0.06647xy0.02260.6524
      FL/FDZ = −587.30009 + 7.92364x + 10.20365y − 0.11231x2 − 0.04611y2 − 0.02193xy0.05780.1059
      VLZ = −691.3203 − 145.7474x + 58.2785y + 11.404x2 + 0.1355y2 − 3.7184xy0.03720.3282
      VDZ = −531.15 + 12.6525x + 9.5999y − 2.3297x2 − 0.1494y2 + 0.9469xy0.02300.6162
      VL/VDZ = 25.438914 − 1.402947x − 0.076717y + 0.135262x2 + 0.005649y2 − 0.047789xy0.11810.0018
      WBDZ = 4.142 − 0.3356x − 0.002205y + 0.00756x2 + 0.00002628y2 − 0.0000636xy0.02720.0007
      CrZ = 305.50611 − 11.71736x − 2.30488y + 0.06669x2 + 0.00115y2 + 0.08674xy0.03090.4412
      H, height; DBH, diameter at breast height; V, volume; FL, fiber length; FD, fiber diameter; FL/FD, ratio of FL to FD; VL, vessel length; VD, vessel diameter; VL/VD, ratio of VL to VD; WBD, wood basic density; Cr, degree of crystallinity.

      Table 5. 

      Regression equations obtained by binary quadratic trend surface analysis.

    • PurposeWood productsPulpwood
      TraitOverall meanMean value of superior provenanceG (%)Mean value of superior provenancesG (%)
      DBH (cm)12.52 ± 0.2213.01 ± 0.473.9113.16 ± 0.125.11
      H (m)11.98 ± 0.2412.12 ± 0.481.1712.69 ± 0.345.93
      V (m3)0.08 ± 0.000.09 ± 0.0112.500.10 ± 0.0025.00
      FL (μm)1,422.97 ± 17.671,403.86 ± 34.67−1.341,472.35 ± 27.673.47
      FD (μm)32.32 ± 0.1431.96 ± 0.35−1.1132.58 ± 0.260.80
      FL/FD43.97 ± 0.4143.90 ± 0.78−0.1645.17 ± 0.702.73
      VL (μm)657.14 ± 8.63654.00 ± 26.61−0.48651.55 ± 27.53−0.85
      VD (μm)162.43 ± 2.60157.31 ± 7.60−3.15168.86 ± 3.753.96
      VL/VD4.10 ± 0.094.22 ± 0.242.933.89 ± 0.12−5.12
      WBD (g/cm3)0.34 ± 0.000.35 ± 0.012.940.33 ± 0.00−2.94
      Cr (%)51.35 ± 0.2852.62 ± 0.842.4750.85 ± 0.66−0.97

      Table 6. 

      Realized gains in all studied traits based on selection of superior N. cadamba provenances using the overall mean of each trait as a threshold.

    • ProvenanceLatitude
      (°N)
      Longitude
      (°E)
      Altitude
      (m)
      Annual average temperature
      (°C)
      Minimum temperature
      (°C)
      Maximum temperature
      (°C)
      Frostless
      period
      (d)
      Average annual precipitation
      (mm)
      GXLZ22.36106.8426922.20.839.93521,260
      GXFCG21.77107.3523521.81.437.83602,512
      GXNN22.85108.48021.7−2.440.43641,304.2
      GDGZ23.1113.211022.1039.33461,696.5
      GDYF22.1112.0234621.5−139.13451,670.5
      YNBS25.0899.16167017.4−4.240.42831,710
      YNDH24.0897.3978018.9−2.935.72991,544
      YNJH21.02101.04552.7212.741.13651,197
      YNMS24.298.9591319.6−0.636.23151,650
      YNMN21.4101.3631210.538.43311,540

      Table 7. 

      Geographic locations of the sampled N. cadamba populations and their climatic properties