Free Access

Table I

Biomass accumulation measurements in two contrasting P. cathayana populations exposed to different UV-B levels under well-watered or drought-stressed conditions.

Population Treatment Shoots (g) Roots (g) Total biomass (g) R / S RWC (%)
Stems Leaves
JZ W 24.66 ± 1.88c 17.05 ± 1.07c 8.39 ± 0.82b 50.10 ± 3.59c 0.20 ± 0.01ab 94.44 ± 0.84c
WU 8.35 ± 0.86b 6.21 ± 0.51b 3.00 ± 0.43a 17.57 ± 1.72b 0.20 ± 0.02ab 93.65 ± 2.41bc
D 0.63 ± 0.06a 0.98 ± 0.08a 0.43 ± 0.10a 2.05 ± 0.15a 0.27 ± 0.06bc 74.56 ± 1.36a
DU 0.25 ± 0.04a 0.53 ± 0.03a 0.16 ± 0.04a 0.93 ± 0.09a 0.20 ± 0.04ab 71.95 ± 2.58a
DT W 33.61 ± 2.89d 27.03 ± 1.98e 24.68 ± 3.80d 85.32 ± 7.48e 0.41 ± 0.05de 93.24 ± 0.78bc
WU 26.24 ± 1.20c 21.14 ± 1.04d 16.64 ± 1.82c 64.03 ± 3.79d 0.35 ± 0.03cd 93.76 ± 0.87bc
D 1.89 ± 0.25a 2.83 ± 0.31a 2.29 ± 0.39a 7.01 ± 0.86a 0.49 ± 0.06e 87.09 ± 3.15b
DU 0.94 ± 0.23a 0.91 ± 0.06a 0.21 ± 0.15a 2.06 ± 0.20a 0.12 ± 0.02a 76.60 ± 3.31a
P(P) 0.000 0.000 0.000 0.000 0.000 0.018
P(D) 0.000 0.000 0.000 0.000 0.483 0.000
P(U) 0.000 0.000 0.001 0.000 0.000 0.043
P(P×D) 0.000 0.000 0.000 0.000 0.057 0.008
P(R×U) 0.038 0.195 0.325 0.457 0.004 0.297
P(D×U) 0.000 0.000 0.019 0.000 0.002 0.051
P(P×D×U) 0.020 0.021 0.852 0.132 0.046 0.151

JZ, the low altitude population; DT, the high altitude population. ANOVA: P(P) : population effect; P(D) : drought effect; P(U) : UV-B effect; P(P×D) : population × drought effect; P(P×U) : population × UV-B effect; P(D×U) : drought × UV-B effect; P(P×D×U) : population × drought × UV-B effect. W, well-watered; WU, well-watered+enhanced UV-B radiation condition; D, drought; DU, drought+enhanced UV-B radiation condition. Values followed by the same letter in the same column are not significantly different at the P < 0.05 level according to Duncan’s multiple range test. Values are means ± SE, n = 10.