Table 1.

Biomass, P concentration, total and specific root length and proportion of root length with different diameters to total root length of wheat grown with different P supplies. Each value is the mean (±SE) of five replicates. Different letters in a given column denote significant differences among P rates (P ≤ 0.05).

P rate (mg kg−1)	Shoot biomass (g per pot)	Root biomass (g per pot)	Shoot P concentration (mg g−1)	Total root length (m per pot)	Specific root length (m g−1)	Proportion of root length in different diameters to total root length (%)
						<0.2 mm	0.2–0.4 mm	>0.4 mm
0	0.25 ± 0.01f	0.15 ± 0.00f	0.98 ± 0.03h	26.3 ± 1.2d	173 ± 6f	69.5 ± 0.7g	24.3 ± 0.6a	6.2 ± 0.3bc
2.5	0.30 ± 0.01f	0.18 ± 0.01ef	0.97 ± 0.03h	32.2 ± 1.5dc	180 ± 3f	70.9 ± 1.0gf	23.6 ± 0.8ab	5.5 ± 0.2cd
5	0.28 ± 0.02f	0.18 ± 0.01ef	1.09 ± 0.06h	37.5 ± 2.7dc	210 ± 8e	73.8 ± 0.9efg	21.3 ± 0.6bc	4.9 ± 0.4de
10	0.32 ± 0.02f	0.19 ± 0.01e	1.23 ± 0.03h	43.3 ± 4.3c	224 ± 9de	76.4 ± 1.3cd	19.4 ± 1.1cd	4.2 ± 0.3efg
25	0.68 ± 0.04e	0.26 ± 0.02d	2.35 ± 0.06g	78.4 ± 6.1ab	295 ± 8a	81.3 ± 1.1b	15.3 ± 1.1efg	3.4 ± 0.2g
50	1.06 ± 0.05d	0.28 ± 0.01d	3.18 ± 0.05f	80.6 ± 8.0ab	289 ± 18ab	84.6 ± 0.9a	11.9 ± 0.6h	3.5 ± 0.3fg
75	1.25 ± 0.03c	0.32 ± 0.01ab	3.68 ± 0.09e	84.0 ± 4.7a	265 ± 15abc	81.8 ± 0.8ab	13.7 ± 0.8gh	4.5 ± 0.2def
150	1.49 ± 0.03b	0.29 ± 0.01bcd	4.71 ± 0.13d	75.7 ± 5.2ab	261 ± 8bc	78.9 ± 1.6bc	15.0 ± 1.1fg	6.1 ± 0.5c
300	1.44 ± 0.05b	0.28 ± 0.02cd	5.08 ± 0.19c	69.6 ± 7.0b	244 ± 10cd	76.1 ± 1.1cd	16.6 ± 0.7ef	7.3 ± 0.4ab
600	1.45 ± 0.05b	0.31 ± 0.01abc	5.83 ± 0.15b	79.3 ± 2.4ab	252 ± 8cd	75.1 ± 0.9de	17.5 ± 0.7de	7.4 ± 0.2a
1200	1.68 ± 0.12a	0.34 ± 0.01a	7.12 ± 0.05a	82.9 ± 5.3ab	245 ± 15cd	72.5 ± 1.8efg	19.4 ± 1.1cd	8.2 ± 0.8a