Abstract:
Soil test based fertilizer recommendation concurrent to the actual limiting nutrients for a given
crop helps to supply adequate and balanced plant nutrients for sustainable crop production
without affecting soil health negatively. Blended NPSB fertilizer is a newly introduced fertilizer
for crop production in the study area. However their optimum rate for maize crop production
and their impact on selected soil property is not yet determined in the study area. Therefore a
study was conducted to investigate the effects of blended NPSB fertilizer rates on selected soil
properties, maize yield and yield components in Bedele district at Banshure Kebele during the
2021main cropping season. The experiment was laid out in randomized complete block design
(RCBD) with three replication of the treatments (0, 25, 50, 75, 100, 150, 200, 250 and 300 kg ha 1
) of blended NPSB fertilizer rates supplemented with the recommended nitrogen rate for maize
production in Bedele District. Selected soil properties before and after trial were analyzed
following standard laboratory procedure at soil laboratory of Bedele Agricultural Research
Center. Soil analytical results before planting indicated that, the soils of the research sites had
clay textural class, are moderately acidic (5.48 and 5.47), medium in OC content (2.04 and
2.12%), had low TN (0.17 and 0.18%), medium available P (1.67 and 1.77 mg kg-1
), low
available S (9.26 mg kg-1
), low available B (0.3 and 0.36 mg kg-1
), medium CEC (20.94 and
22.64 cmol (+) kg-1
) and very low PBS (16.85 and 16.29%), for Alle and Abu respectively. The
analysis of variance indicated that, the blended NPSB fertilizer rate highly significantly affected
soil pH, available phosphorus, available boron, available sulfur, maize growth, yield and yield
components. Moreover, the result showed that economically feasible grain yield (7173.6 kg ha-1
)
and net benefit (74897.58 ETB ha-1
) with highest marginal rate of return of 2957% were
obtained from the plot treated with 150 kg ha-1
of blended NPSB fertilizer rate. Therefore, based
on the result obtained from this study, application of 150 kg ha-1
of blended NPSB fertilizer rate
and recommended nitrogen can be tentatively suggested as economically profitable for the
production of maize at the study area.
