Agriculture Reference
In-Depth Information
TABLE 3.10
Macronutrient Uptake in the Shoot and Grain of Soybean under Different Lime Rates
Lime Rate (Mg ha
−1
)
N (kg ha
−
1
)
P (kg ha
−
1
)
K (kg ha
−
1
)
Ca (kg ha
−
1
)
Mg (kg ha
−
1
)
Shoot
0
34.4
1.54
46.2
19.9
12.6
3
35.4
1.77
58.8
27.6
16.0
6
37.5
1.76
57.5
31.0
20.3
12
32.3
1.79
63.3
31.6
18.0
18
45.7
2.22
76.0
40.6
23.7
Average
37.1
1.82
60.4
30.1
18.1
F-test
Lime
NS
*
*
**
**
CV (%)
20.0
14.9
19.1
18.5
20.1
Grain
0
180.8
9.17
49.3
8.3
6.3
3
256.3
13.18
71.2
11.8
9.5
6
280.0
14.29
77.5
13.4
10.2
12
278.5
15.37
78.3
12.6
10.7
18
296.5
17.09
80.2
12.0
10.6
Average
258.4
13.82
71.3
11.6
9.5
F-test
Lime
**
**
**
NS
**
CV (%)
7.0
8.5
7.7
19.5
7.5
Source:
From Fageria, N.K. et al. 2013b.
Commun. Soil Sci. Plant Anal
. 44:2941-2951. With permission.
*Significant at the 5% probability level.
**, NS: Significant at the 1% probability level and nonsignificant, respectively.
accumulated in the grain) was 11 kg for N, 200 kg for P, 39 kg for K, 238 kg for Ca, and 292 kg for
Mg. This means Mg was having maximum efficiency in grain production and N was having mini-
mum efficiency. Similar results were reported by Fageria (2001a) for soybean grown on Brazilian
Oxisol.
The uptake of all the macronutrients in the grain was having a highly significant (P < 0.01)
quadratic association with grain yield (Table 3.12). Grain yield was having 89% variability due to
N uptake, 91% variability due to P uptake, 86% variability due to K uptake, 61% variability due
to Ca uptake, and 79% variability due to Mg uptake. This means that the N and P uptakes were
having maximum influence on grain yield compared to the K, Ca, and Mg uptakes. Nitrogen and
P improved the number of pods per plant or per unit area in legumes in Oxisols, which might
have been responsible for the higher variation in grain yield due to these nutrients (Fageria et al.,
2006).
A large part of the N accumulation in crop species during the growth cycle is translocated from
the vegetative to the reproductive plant parts. Mae (1997) reported that the amount of N absorbed
by the plant during the grain filling period is much smaller than the amount of N accumulated in
mature grain, and a large part of grain N is translocated from vegetative organs. Nitrogen distribu-
tion studies showed that 30-80% of the N accumulated in the rice grain originated from transloca-
tion from vegetative tissue after heading (Guindo et al., 1992; Ntanos and Koutroubas, 2002). Xiong
et al. (2013) also reported that, in rice preheading, N accumulation was having a highly significant
correlation (r = 94*) to N translocated to grain.
