Effects of Compost and Phosphorus Fertilizer Rate on the Yield and Yield Related Traits of Garlic at Bale Highlands, South Eastern Oromia

Abstract

Field experiment has been conducted to determine the effects of compost and mineral Phosphorus fertilizer rate on the yield components and yield of Garlic at South eastern Ethiopia, Bale zone, Dinsho district. Compost was prepared at Sinana Agricultural Research centre compound from different crop residue and other waste materials. Experiment was done using RCBD experimental design with factorial arrangement. The treatments for this experiment were four rates of compost (0, 10, 20 and 30 ton/ha) and four rates of phosphorus fertilizer (0, 46, 69 and 92 kg/ha). There was 16 total numbers of treatments. Each treatment replicates three times. Yield related traits such as; plant height, number of cloves per bulb, average weight of bulb and total bulb yield were recorded and inserted to GenStat computer software. Analysis of variance showed that the main effects of both compost and phosphorus fertilizer on all yield traits and yield was significant. Additionally, interaction of compost and phosphorus fertilizer significantly affects all parameters. Accordingly, maximum plant height (46.11cm), maximum number of cloves (33.58), maximum average weight of bulb (23.56gm) and total bulb yield (70.74 Qt ha^-1) was obtained from the treatment received 20ton ha-1 of compost combined with 69kg ha^-1 of phosphorus fertilizer. On the other hand the shortest plant (31.47cm), lowest number of cloves per bulb (24.03), the lowest weight of single bulb (13.94gm) and lowest total bulb yield (46.48 Qt ha^-1) was obtained from control plot. Moreover, partial budget analysis had been done to determine the profitability of treatments. As a result, the treatment supplied with 20ton ha-1 of compost combined with 46kg ha^-1 of phosphorus fertilizer shows maximum marginal rate of return (8531.0%). To conclude, the treatment with maximum yield showed minimum marginal rate of return in relative to maximum marginal rate of return. Since major problem of local farmers is cost of fertilizer it is important to focus on cost benefit analysis result for recommendation. Consequently, 20ton ha-1 of compost without phosphorus fertilizer is recommended to be used by farmers to be profitable.