Biomass and Yield of Peanut Grown on Tropical Soil Amended with Sewage Sludge Contaminated with Lead
Table 4
Dry matter of peanut as a function of Pb rates applied to soil with sewage sludge, time of sewage sludge application, mineral fertilization, and control.
Dry matter (g per pot)
Treatment
Shoot
Roots
Pods
Pod husks
Kernels
Additional treatments
Control
54.76a†
3.59a
32.61a
13.91a
18.10a
Mineral fertilization
46.31a
3.06a
41.22a
15.73a
25.49a
Sewage sludge
Pb rate (mg kg−1)
3
67.99a
5.28a
44.23a
17.02a
27.39a
21
66.81a
4.90a
47.50a
18.11a
29.44a
42
74.65a
5.42a
42.04a
16.98a
25.03a
Time of application
30 d before sowing
77.14a
5.66a
41.18a
16.87a
24.40b
At the day of sowing
62.49a
4.73a
48.00a
17.87a
30.16a
Analysis of variance
Source of variation
F test‡
Additional treatments
NS
NS
NS
NS
NS
Pb rate
NS
NS
NS
NS
NS
Time of application
NS
NS
NS
NS
*
Pb rate × time of application
NS
NS
NS
NS
NS
Sewage sludge × additional treatments
*
**
*
*
NS
CV (%)
29.46
23.67
17.66
12.16
22.45
†Means followed by same letter in column within additional treatments and each factor of factorial do not differ significantly by Tukey test at P < 0.05.
‡NS: not significant. *, **significant at P < 0.05 and P < 0.01, respectively.