Table 5.

O₂ consumption rate of rice (‘Amaroo’) roots grown in aerated solution at high P (200 μm) and then transferred to aerated or stagnant nutrient solution at low (1·6 μm) or high P (200 μm) supply for 4 d

	O2 consumption rate (n mol O2 g−1 f. wt s−1)
Part of root	1·6 μm P	200 μm P
0–20-mm tip	4·67 ± 0·75	5·22 ± 0·47
20–40-mm zone	2·61 ± 0·02	2·50 ± 0·30

Roots for each zone were cut into 5-mm segments and measured in the same solution as the growth medium. Values are means of four replicates ± standard errors. l.s.d. (P < 0·05) for effect of different root part, 0·97. f. wt, fresh weight.