Agriculture Reference
In-Depth Information
400
200
Y = 3648.99 - 1074.90X + 81.05X
2
R
2
= 0.6721**
0
4
5
6
7
Soil pH in H
2
O
FIGURE 6.12
Influence of soil pH on the uptake of Fe in the shoot of dry bean plants. (Adapted from
Fageria, N. K. and V. C. Baligar. 1999.
J. Plant Nutr
. 22:23 -32.)
the release of phytosiderophores by Fe deficiency was reported to increase according to the resis-
tance of the species to lime-induced chlorosis (Fageria et al., 2006).
Iron in adequate amounts developed N
2
-ixing nodules in dry bean, an increase in yield, and
improved NUE (Garg, 1987). The use of ammoniacal N fertilizers lowers soil pH and improves Fe
uptake in crop plants. The author studied the influence of N on the uptake of Fe in the shoots of dry bean
plants (Table 6.16). The uptake of Fe was significantly increased with the increasing N rates in the range
of 0-200 kg ha
−1
. Nitrogen application was responsible for 83% variation in the Fe uptake. The positive
association of N with Mn was related to the improvement in dry matter production of dry bean (Fageria
and Baligar, 2005). Fageria (2009) reported that N uptake in the form of NO
−
can increase soil pH due
to the liberation of OH
−
ions, thus decreasing the iron solubility and uptake. If NH
+
N is absorbed, the
reverse will occur: a decrease in soil pH may solubilize iron in the soil, and its uptake may increase.
Kutman et al. (2011) reported that N enhanced the uptake of iron by wheat plants. These authors
also reported that N nutrition is a critical factor in both the acquisition and grain allocation of Fe in
wheat. Kutman et al. (2011) reported that the positive effect of N on the uptake of Fe in the grain of
TABLE 6.16
Influence of N on the Uptake of Fe in the Shoot
of 60-Day-Old Dry Bean Plants
N Rate (kg ha
−1
)
Fe Uptake (g ha
−1
)
0
57.9
40
142.8
80
225.4
120
219.0
160
365.1
200
519.1
R
2
0.83**
**Significant at the 1% probability level.
