Agriculture Reference
In-Depth Information
10.0
7.5
5.0
Y = 49.4551 - 12.6890X + 0.8826X
2
R
2
= 0.8992**
2.5
0
4
5
6
Soil pH in H
2
O
7
FIGURE 6.10
Influence of soil pH on the uptake of Cu in the shoot of dry bean plants. **—Significant at the
1% probability level. (Adapted from Fageria, N. K. and V. C. Baligar. 1999.
J. Plant Nutr
. 22:23 -32.)
Fageria and Baligar (2005) studied the influence of N on the uptake of Cu in the shoots of dry
bean plants (Table 6.14). The uptake of Cu was significantly increased in a quadratic fashion with
increasing N rates in the range of 0-200 kg ha
−1
. The variation in Cu uptake was 78% due to N fer-
tilizer application. Pederson et al. (2002) also reported that N concentration was highly correlated
with Zn concentration in the aboveground plant parts of ryegrass.
6.3.3 n
ItroGen
versus
m
anGanese
Manganese plays an important role in the growth and development of plants. It plays an important
role in the photolysis of water in chloroplasts, regulation of enzyme activities, and protection against
oxidative damage of membranes (Alloway, 2008). Sillanpaa (1990) reported that Mn deficiency
is present in about 10% soils in 15 different countries. In acid soils, liming is the main factor for
Mn deficiency (Fageria et al., 2002; Fageria and Stone, 2008). Figure 6.11 shows that Mn uptake
decreased significantly in dry bean plants when the soil pH was raised from 4.8 to 7.0 in a Brazilian
Inceptisol.
TABLE 6.14
Influence of N on the Uptake of Cu in the Shoot
of 60-Day-Old Dry Bean Plants
N Rate (kg ha
−1
)
Cu Uptake (g ha
−1
)
0
3.0
40
5.2
80
8.9
120
9.6
160
15.0
200
18.7
R
2
0.78**
**Significant at the 1% probability level.
