Soil fertility management for improved wheat production in Uganda
1. Soil fertility management for improved wheat production in Uganda
Chemayek B, Wasukira A, Wobibi S, and Wagoire W.W
Introduction: In Uganda, wheat is produced by smallholder farmers on the slopes of Mt. Elgon (East) and the south-west
highlands at altitudes between 1800 -2400masl. These areas have steep slopes that are prone to erosion, contributing to a loss in
fertility and occasional landslides. Wheat production in these areas is curtailed by low soil fertility due to intensive cropping, and
use of poor quality seed of old varieties. Farmers achieve yields of 0.5t/ha but there are potential yields of 2.5t/ha. In Kapchorwa
and Kween, less than 30% of farmers use fertilizer for wheat production, and this decreases to less than 5% in the south-west
highlands. This study carried out soil fertility studies in eastern Uganda from August 2010 to Aug 2012 at 4 sites, to determine the
most effective fertilizer rates for wheat production.
Objectives: (i) Determine appropriate fertilizer application rates for wheat; (ii) Assess how different farmer wheat varieties
perform under different fertilizer levels; (iii) Promote use of fertilizers and improved seed at farm level
Methodology: Study was conducted in four sites of Kapchorwa, Kween, Bukwo and Bulambuli from Aug 2010 to Aug 2012 for
three seasons. Five genotypes; Fahari, Kwale, Nkugu, UW 309 and UW 400 were evaluated under four fertilizer levels (90Kg ha-1
N and 80Kg ha-1 P Kg/ha; 60Kg ha-1 N and 50Kg ha-1 P; 30Kg ha-1 N and 20Kg ha-1 P Kg/ha and no fertilizer at all as a check) in a
split plot design. The main plots were fertilizer treatments while the genotypes constituted the subplots that were of 4 rows of 5
m length and inter-row spacing of 0.3 m. Data on establishment, number of tillers, disease incidence and severity, plant
height, lodging, head length and yield (Kg) was collected and analyzed using SAS.
Results and Discussion
Source df Mean Squares
Establish Tillers Plt Height Head length Agro Score Stem Rust Yield
Site 3 6.43*** 51.65*** 2882.56*** 54.20*** 23.31** 856*** 5.89***
Treatment (Trt) 3 5.89*** 7.19*** 2742.16*** 14.57*** 76.93*** 44.36 3.06*
Variety (Var) 7 7.89*** 0.68 364.64** 11.44*** 8.76 353.38*** 4.12***
Rep 2 0.9 1.72 725.21** 1.31 24.19* 685.12*** 2.8
Site*Trt 9 6.56*** 3.93*** 531.95*** 3.99*** 21.64*** 39.81 1.65
Site*Var 12 2.92*** 1.42* 654.87*** 10.67*** 10.32* 828.12*** 2.66**
Trt*Var 15 0.717081 1.07 105.3556 0.88 15.09*** 49.71 0.62
Site*Trt*Var 36 0.530627 0.85 68.37347 1.08 11.92*** 52.32* 0.34
*Value significant at P≤0.05; **Value significant at P≤0.01;***Value significant at P≤0.001
Results indicated highly significant difference Nkungu the local genotype performed poorly under
between site and all measured parameters. all treatments compared to improved genotypes. This
Considerable significant differences were also reflects genotypic differences in adaptation to
recorded between treatments and measured different fertilizer levels. The results indicated high
parameters. The observed highly significant responsiveness of improved genotypes to nutrient
differences is because the soils in these sites are applications implying that theses genotypes have had
highly nutrient deficient and so any soil nutrient a lot of good traits incorporated in them among which
amendments results in increased yields. is improved response to nutrient applications.
The lack of positive response to fertilizer by Nkungu was because of being
There were significant differences among
very tall and with weak stems that led to early lodging in plots with fertilizer
genotypes for all parameters Fahari yielding
leading to low yields due to inadequate grain filling. Analysis of variance
higher (1.84 t/ha) and UW369 (1.62t/ha) at 90N
indicated considerable significant interaction between site and treatments
Kg/ha while Kwale (1.96t/ha) and UW400
for all parameters. Further more significant interactions were in site and
(2.0t/ha) gave higher yield at 60N Kg/ha.
variety
Yield of five wheat genotypes at different Conclusion: Fertilizer application increased yields in improved genotypes
2.50 fertilizer levels than the local cultivar. Genotypes responded differently to fertilizer levels
with Kwale and UW400 giving better yields at 60N Kg/ha. These results
2.00 indicate the potential for improving wheat productivity through application
30N of appropriate amounts of fertilizer and use of elite varieties, in order to
Yield (t/ha)
1.50
improve the livelihoods of wheat farmers.
1.00 60N
References
0.50 90N William Wamala Wagoire (2006). Quantification of the value of improved
wheat production options in South-western Uganda. Uganda Journal of
0.00 Agricultural Sciences, 12(1): 22-28
Taye Belachew & Yifru Abera (2010). Assessment of Soil Fertility Status with
Depth in Wheat Growing Highlands of Southeast Ethiopia. World Journal of
Agricultural Sciences 6 (5): 525-531
Genotypes