Soil fertility status and wheat nutrient content in Vertisol cropping systems of central highlands of Ethiopia

Abstract

Background: Land degradation reduces agricultural productivity and poses a serious threat on food security status of households. In Ethiopia, farmers have been using only urea and di-ammonium phosphate for more than 15 years. Several reports that indicate lack of response to these fertilizers, which could be due to limitation of nutrients other than nitrogen and phosphorus. Therefore, the present study was initiated to evaluate the soil fertility status of ten sites in central highlands Vertisols of Ethiopia and wheat nutrient content. Results:The physico-chemical properties of soils showed that the soils were clayey in texture, neutral to slightly alkaline (pH 7.2-7.9) and low to medium in their organic matter (1.6-3.2 %) content. Total N content was low in 100 % of the samples while 80 % of the soil samples showed P deficiency (<10 mg kg −1 ). Exchangeable K, Ca and Mg in all soil samples were high, while available sulfur was low. On the other hand, K to Mg ratio varied from 0.13:1 to 0.44:1, indicating Mg induced K deficiency. All soil samples were adequate when analyzed by ammonium bicarbonate diethylene tri-amine penta-acetic acid extractable Cu (>0.5 mg kg ) and acid ammonium oxalate extractable Mo (<0.1 mg kg −1 ) were found to be low in all soil samples. The plant analysis data showed that all samples were low in N, P and K, while high in Ca and Mg concentrations. The deficiency of tissue K content was not predicted by the soil exchangeable K test. Plant micronutrient analysis showed that Cu, Fe, Mn and Cl concentrations were within the sufficiency range while Zn was deficient in all of the samples. Conclusions:Soil and/or tissue test results are indicative of deficiency of N, P, K, S, Zn, B and Mo that could be amended by fertilizer application, although more data are needed to thoroughly support this conclusion. The highest correlation (r > 0.90) between soil and plant nutrient content was observed for P, K, Mg, Cu, Fe, Mn and Zn, implying that flag leaves at flowering stage can be used to calibrate soil and plant contents for the deficient nutrients.

Response of Chickpea (Cicer aritienum&nbsp;L.) to Sulphur and Zinc Nutrients Application and&nbsp;Rhizobium&nbsp;Inoculation in North Western Ethiopia

“…Based on the rating developed for those nutrients it were found to be above the optimum range (Berhanu, 1985;Hazelton and Murphy, 2007). This result is also in agreement with former findings in different vertisols dominated areas of Ethiopia (Desta, 1982;Fassil and Charles, 2009;Hailu et al, 2015;Kamara et al, 1989;Lemma and Smit, 2008).…”

“…The low S was also expected because the experimental soil had low organic matter content (source of about 95% of S) indicating that it's potential to supply S to plant growth through mineralization is low. Other authors also reported deficiency in S in Vertisols of Ethiopia (EthioSIS, 2016;Fanuel, 2015;Habtamu et al, 2014;Hailu et al, 2015;Lelago et al, 2016).…”

Effect of bagasse ash and filter cake amendments on wheat (Triticum turgidum L.var. durum) yield and yield components in nitisol

“…Although many efforts have been made to develop high-yielding variety of wheat in Ethiopia, the productivity of wheat is still far below the potential yield reported elsewhere as a result of soil quality depletion and low soil fertility (Harden 2001;Lal 2001). The deficiency of some micronutrient besides widespread N and P (and localized K) deficiencies in major wheat-growing areas of Ethiopian has been recently reported (Hailu et al 2015). These problems are aggravated by continuous nutrient depletion due to the complete harvest of whole plant biomass and losses in runoff and soil erosion (Vlek 1993;Sanchez et al 1997), which have led to negative nutrient balances (Stoorvogel and Smaling 1990).…”

Growth, yield component and yield response of durum wheat (Triticum turgidum L. var. Durum) to blended NPS fertilizer supplemented with N rates at Arsi Negelle, Central Ethiopia

“…The results from both of these initiatives showed deficiency of 3 to 6 nutrients N, P, S, Zn, Mo and B. in most parts of the country and crops responded to the application of additional nutrient. Moreover, the plant analysis data from the same sites indicated that wheat plants were deficient in N, P, Zn and K (Hailu et al, 2015).…”