Table 2.
Biomass accumulation, total Zn content, and root-to-shoot Zn translocation index in IR74 grown under different Zn concentrations in Experiment 1.
| Growth stages | Trait | ZnSO4·7H2O concentrations (μM) | ||||
|---|---|---|---|---|---|---|
| 0.005 | 0.15 | 1.5 | 3.5 | 6.5 | ||
| Early vegetative (14 d in ANS) | Shoot dry weight (g plant–1) | 0.37±0.02 b | 0.54±0.04 a | 0.49±0.03 a | 0.47±0.01 a | 0.48±0.02 a |
| Root dry weight (g plant–1) | 0.16±0.01 b | 0.26±0.03 a | 0.23±0.02 a | 0.24±0.01 a | 0.22±0.01 a | |
| Total dry matter (g plant–1) | 0.53±0.03 b | 0.80±0.06 a | 0.72±0.04 a | 0.71±0.02 a | 0.70±0.03 a | |
| Total Zn content (μg plant–1) | 9±1 d | 12±2 d | 21±0.6 c | 39±0.8 b | 47±4 a | |
| Root-to-shoot Zn translocation index (%) | 50±2 b | 50±3 b | 69±1 a | 67±2.5 a | 66±3 a | |
| Maximum tillering (40 d in ANS) | Shoot dry weight (g plant–1) | 1.3±0.03 b | 1.6±0.09 a | 1.8±0.1 a | 1.7±0.09 a | 1.7±0.08 a |
| Root dry weight (g plant–1) | 0.73±0.06 b | 0.87±0.02 ab | 0.96±0.03 a | 0.89±0.06 a | 0.87±0.002 ab | |
| Total dry matter (g plant–1) | 1.6±0.06 b | 1.9±0.07 a | 2.1±0.1 a | 2.0±0.1 a | 2.0±0.05 a | |
| Total Zn content (μg plant–1) | 26±4 d | 33±2 d | 81±0.8 c | 111±7 b | 160±5 a | |
| Root-to-shoot Zn translocation index (%) | 51±0.6 a | 52±3 a | 45±2 b | 48±1 ab | 41±3 c | |
| Maturity | Shoot dry weight (g plant–1) | 3.1±0.8 b | 3.5±0.2 b | 6.4±0.9 a | 6.1±0.2 a | 6.1±0.2 a |
| Root dry weight (g plant–1) | 0.8±0.1 c | 1.3±0.02 b | 1.6±0.2 ab | 1.8±0.08 a | 1.8±0.06 a | |
| Total dry matter (g plant–1) | 4.0±0.9 b | 4.8±0.2 b | 8.3±1 a | 8.2±0.2 a | 8.3±0.2 a | |
| Total Zn content (μg plant–1) | 56±2 d | 89±3.6 d | 195±17 c | 322±18.7 b | 595±36.4 a | |
| Root-to-shoot Zn translocation index (%) | 58±4 a | 52±3 ab | 44±3 bc | 34±3.8 c | 35±4.3 c | |
Values within a row with different letters are significantly different between different Zn treatments at 5% LSD. The values given are means ±SE (n=3).