Abstract:
The use of locally available, nutrient rich organic sources is an effective means for
improving soil fertility and increasing crop yield in view of the escalating cost of
inorganic fertilizers and low fertilizer use efficiency of crops in Ethiopia. This study was
conducted in Sebeta Hawas Woreda with the objective of comparing the effectiveness of
bio-slurry and inorganic fertilizer on soil properties, growth and yield of white cabbage.
The questionnaire survey was done to obtain information on the family size, number of
cattle, type of fertilizer used, the amount of money saved by biogas using households
when replacing chemical fertilizer with bio-slurry, bio-slurry storage and management,
household yield increment and perception of soil fertility improvement by using bioslurry
as organic fertilizer. Laboratory analysis and field experiment were done on bioslurry
in liquid and composted form to determine the nutrient content and effect of bioslurry
and inorganic fertilizer on plant height, number of leaves, head diameter, head
yield and nutrient content of cabbage as well as physical and chemical properties of the
soil. The maximum plant height (cm) was obtained from T6 (recommended dose of
inorganic fertilizer (RDIF) + biogas slurry compost (BGSC) at (80q/ha), while the lowest plant
height (cm) was recorded in T1 (control). Cabbage plants treated with T7 ( (1/2 RDIF) +
iv
(½ BGSC )), T6 ( (RDIF) + BGSC at 80q/ha),T5 (BGSC at (80q/ha)) and T6 showed the
highest number of leaves at 2,4,6 and 8 weeks after transplanting respectively. With
regard to fresh weight of individual head and individual head diameter (cm), T6 showed
the highest value for fresh weight of individual head and T5 showed the highest values
for individual head diameter (cm). Considering major nutrient content of white cabbage,
it can be inferred that bio-slurry and inorganic fertilizer showed no significant effects on
leaf phosphorous and potassium value but bio-slurry applied in combination with
inorganic fertilizers has positive influence on nitrogen content. The study also revealed
that there was significant contribution of bio-slurry to increase organic carbon,
phosphorus and cation exchange capacity of soil.
Key words: Growth and head yield, soil properties, bio-slurry, fertilizer