Agriculture Reference
In-Depth Information
TABLE 6.1
Dry Weight of Shoot and P Uptake in the Shoot of 60-Day-Old Dry Bean
Plants as Influenced by Nitrogen Rates
N Rate (kg ha
−1
)
Shoot Dry Weight (kg ha
−1
)
P Uptake (kg ha
−1
)
0
220
0.6
40
494
1.4
80
814
1.6
120
828
2.1
160
1260
2.9
200
1659
3.4
R
2
0.83**
0.81**
** Significant at the 1% probability level.
soybean production. Abbasi et al. (2012) also reported that the application of P significantly
increased the uptake of N in soybean.
The author studied the uptake of N under different P levels in 14 cover crop species (Table 6.2).
Uptake (concentration × dry matter) was significantly affected by P levels as well as cover crop
treatments (Table 6.2). Similarly, P × cover crop interactions were also significant for N uptake,
TABLE 6.2
Uptake of N (mg Plant
−
1
) in the Tops of 14 Tropical Cover Crops under Three
P Levels
P Levels (mg kg
−
1
)
Cover Crops
0 (Low)
100 (Medium)
200 (High)
Crotalaria
5.95f
21.59e
25.47ef
Sunnhemp
58.18de
152.02bcd
176.90cd
Crotalaria
11.11f
35.34e
36.51ef
Crotalaria
13.98def
42.80e
54.27ef
Crotalaria
13.89def
68.16de
109.22de
Calapogonio
11.75ef
38.37e
7.32f
Pueraria
7.31f
27.50e
35.63ef
Pigeon pea (black)
37.90def
97.21cde
87.55def
Pigeon pea (mixed color)
16.58def
76.73de
79.67def
Lablab
48.32def
192.86bc
237.84bc
Mucuna bean ana
123.10c
190.81b
220.79bc
Black mucuna bean
57.63d
194.44b
265.75ab
Gray mucuna bean
190.41b
199.05bc
304.37ab
White jack bean
282.48a
350.79a
376.39a
Average
62.76
120.55
144.12
F-test
P levels (P)
**
Cover crops (C)
**
**
P × C
CV (%)
24.58
**Significant at the 1% probability level. Means followed by the same letters in the same column are not
significant at the 5% probability level by Tukey's test.
