TITLE:
Influence of Tillage and Wood Ash on Zn and Fe Content of Soil, Castor Shoot and Seed
AUTHORS:
I. A. Nweke, C. N. Mbah, C. N. Mbah, S. I. Ijearu
KEYWORDS:
Castor, Iron, Tillage, Wood Ash, Zinc
JOURNAL NAME:
Open Access Library Journal,
Vol.4 No.2,
February
27,
2017
ABSTRACT: The effect of tillage methods
(Mound, Ridge, Flat) and rates of wood ash on soil properties and yield of
castor bean plant were studied in field trial at Abakaliki for 3 years cropping
seasons. The experiment was a split plot in randomized complete block design
with three tillage methods and four rates of wood ash (0 t∙ha-1,
2 t∙ha-1, 4 t∙ha-1
and 6 t∙ha-1), replicated three times.
CropStat Version 7.2 computer software for data management developed primarily
for the analysis of data from agricultural field trials was used to analyze
data collected from the study and mean separation was done using least
significant difference (LSD) at 5% alpha level. The findings from the study
showed for soil heavy metal contents, it was observed that tillage methods had
no effect on the heavy metals except for 1st year cropping
result of Zn and 2nd year cropping result of Fe. The
effect of tillage methods on heavy metal contents of castor shoot showed a significant
difference P rd year result of Fe.
The values obtained from Ridge and Flat were higher when compared with the
value of Mound with regard to soil and castor shoot; heavy metal content with
higher values was more observed in Flat method. The result of heavy metal
content of seed indicated that tillage method had no effect on the heavy metal
contents of the castor seed; the results of Fe, Zn in 1st
and 2nd year planting season were not significant among
the rates of wood ash applied. The effect of tillage and wood ash on heavy
metal content of soil, castor shoot and seed was found to be significant (P -1
(Rd2), 4 t∙ha-1 (Rd4)
and 6 t∙ha-1 (Rd6) on
Fe 2nd year planting result of castor seed was statistically
similar, while the result from Mound method was found to increase the seed uptake
of the tested parameters. The observed values of the tested parameters (Fe, Zn)
in wood ash amended plots in the three years’ study were beyond acceptable limits; hence reservation in the use of wood ash on continuous bases as soil amendment especially at
higher rates. The
findings also indicated that the use of wood ash as soil amendment on
continuous basis on the same piece of land especially at higher rates might constitute pollution
problems on the near future.