Assessment of Soil Chemical Properties and Coffee Leaf Analysis in Goma Woreda of Oromia Region

Abstract

Information on soil test and plant analysis is essential for sustainable soil fertility management and crop production. Conversely, this is lacking for smallholder coffee farms in Gomma district, Southwestern Ethiopia. Thus, the objectives of this study were to assess and determine the nutritional status of the soil-plant relation from coffee growing farms in Gomma district. Accordingly, soil samples, coffee leaves and field history were collected from 10 coffee farms during pinhead phase. Soil samples collected from 0-30 cm depth were prepared and analyzed in the laboratory following standard procedures. For data analysis, descriptive statistics was used. Results showed that the soil pH ranged from strongly to moderately acidic (pH 4.72-5.75) and low to medium in their organic matter (2.68-4.72%) content. Total N content was low in 20% of the samples, while 100% of the soil samples found to be deficient in P content. Exchangeable Ca ranged from low to high, exchangeable Mg in all soil samples was medium, while exchangeable K ranged medium to very high. Nevertheless, K to Mg ratio varied from 0.64:1 to 2.62:1, indicating Mg induced K deficiency in 10%. The plant tissue analysis depicted that 50, 60 and 50% low in N, P and K, respectively, while high in Ca and Mg concentrations. Significant and positive correlations of soil phosphorus, potassium, calcium and magnesium with tissue concentration were existed. For sound conclusion, soil test and crop response calibration, appropriate soil, N, P, K, organic fertilizers and lime are recommended for future work.

Potential of Moisture Conservation Practices to Improve Soil Properties and Nutrient Status of Robusta Coffee Plant

“…The high P under ACS could be due to the high level of SP in the soil at that location. In fact, soil P was significantly positively correlated with leaf P (r = 0.85), agreeing with studies by [72,73]. The positive correlation explains the high P in the soil and leaves under ACS.…”

“…Ca concentrations in leaves were above the optimum ranges of 0.75-1.5% [72] across the treatments, though the relationship was insignificant. Leaf Ca increased significantly along with the SCa contents (r = 0.76).…”

“…Similarly, Bote and Struik [71] observed that coffee grown under shade had more N in the leaves. N was the lowest in coffee under COSS and it was below the optimum range of 2.5-3% [72]. The low N in coffee leaves from open sun could be related to the low nitrogen in the soil, as explained by significant correlation (r = 0.75) between soil nitrogen and leaf nitrogen.…”

“…Mg concentration in the leaves was significantly different across the treatments, with the highest amounts being recorded under ACS and the lowest under COSS [71]. The leaf Mg was within the optimum range of 0.25-0.40% [72] across all the SMCPs, implying that it was available in sufficient amounts for plant utilization. The contributions of SOM and the level of exchangeable SMg could be one explanation for the high leaf Mg contents of coffee.…”

Effect of Nitrogen and Phosphorus Fertilizer Rates on Yield and Yield Components Sorghum (Sorghum bicolor L. Moench) at Kersa Woreda of Oromia Region

“…Also nitrogen is commonly the most limiting nutrient for crop production in the major world's agricultural areas and therefore adoption of good N management strategies often result in large economic benefits to farmers. The various factors accounting for the poor soil fertility include topography, soil erosion, deforestation, population pressure, and continuous cultivation without proper soil fertility maintenance [11][12][13]. Among the major constraints on increased production of sorghum are poor soil fertility, limited supply of production inputs, low prices for the produce, and undeveloped markets [7].…”