Purpose Depletion of soil fertility accounts for the low yield and quality of malting barley (Hordeum vulgare) in Ethiopia. Mineral fertilizers can counteract nutrient depletion but are unaffordable by low-input farmers. Organic amendments can contribute to correct soil degradation but are often unavailable in the required amounts. Therefore, this experiment was conducted to investigate the effects of combined use of organic and mineral amendments on the yield and quality of malting barley, and on selected soil chemical properties at Lemu-Bilbilo district in the southeastern highlands of Ethiopia. Methods Eight treatments were arranged in randomized complete block design with three replications to compare sole and integrated applications of organic and mineral nutrient sources on crop performance attributes and selected soil characteristics. Results Application of 2.82 t ha −1 compost or 1.07 t ha −1 farmyard manure (FYM) along with 18-10 kg ha −1 N-P gave 4234-4443 kg ha −1 grain yield with 15-17 and 32-39% increase over sole organic amendments and control, respectively, and 757% economic benefit. Combining organic and mineral fertilizers also gave 7-17 and 1-6% increase in available soil P and total N content of the soil. Conclusion Combined application of 50% recommended compost (RC) or 50% recommended FYM (RFYM) + 50% recommended NP (RNP) or 33% RC + 33% RFYM + 33% RNP enhanced yield, grain quality, soil attributes and economic benefits. Therefore, integration of organic and mineral amendments is recommended as best agronomic and economic optimum soil fertility management options for sustainable malting barley production in the southeastern highlands of Ethiopia.

Field experiment was conducted in 2012 and 2013 in three districts of Arsi zone, Oromia region, Ethiopia to evaluate the response of bread wheat cultivar "Damphe" under highland vertisols to treatments consisting of 20 factorial combinations of five N rates from urea and four P205 rates from triple super phosphate (TSP). The treatments were laid out in RCBD, replicated three times. All data were subjected to analysis of variance using SAS 9.0 Statistical Analysis Software. Treatment effects on the average grain yield (AGY) and average biological yield (ABY) were very highly significant. Number of spikes m-2, number of seeds/spike, and plant height were also significantly or very significantly affected. The main effects of fertilizer N on AGY, ABY, protein and wet gluten contents, and zeleny values of grains were also very highly significant. Leaf absorption of N increased with increased rates up to 92 kg/ha N. The N recovery efficiency (NRE) at 46 and 92 kg N/ha was 20.9% and 29.4% and the agronomic efficiency (AE) was 10.8 and 13.3 kg grain/ kg N applied, respectively. Above the 92 kg/ha N the increase in both NRE and AE declined or fell reaching 31.4 % and 12.6 kg grains/ kg N. Based on farmers capacity to invest and their inherent tendency to gradually adopt higher rates, a base recommendation of 92-46 (N-P 2 O 5 ) kg/ha, which is equivalent to 160 kg/ha Urea + 100 kg/ha DAP is given. This rate was the treatment with highest marginal rate of return (MRR). Additional recommendation consisting of 138-69, and 115-46 (N-P 2 O 5 ) kg/ha, equivalent to 240 kg/ha Urea + 150 kg/ha DAP and 210 kg/ha Urea + 100 kg/ha DAP is given, based on agronomic data, economic analysis, complexity in management history of different farms, and environmental considerations.

The growing demand for malt has generated interest for improving productivity through sustainable means such as cropping sequences with malting barley along with optimum nitrogen (N) fertilization. Cropping sequence has many benefits for optimum yield and quality, but knowledge of rotational effects of preceding crops on malting barley is still limited. Thus, this study was conducted to determine the effects of legume and non-legume preceding crops, and N fertilization on productivity and quality of malting barley grown the following year in two locations in the southeastern highland of Ethiopia. The experiment was split plot design with six preceding crops (fababean, Ethiopian mustard, potato, linseed, wheat and malting barley) as main plots and four levels of N (0, 18, 36 and 54 kg N ha À1 ) for the succeeding crop as split plot treatments with 3 replications. Malting barley grown after fababean, Ethiopian mustard and potato exhibited 13-16, 14-34 and 14%, respectively grain yield increments compared to growing malting barley after malting barley. Similarly, application of 36-54 kg N ha À1 gave 4-29 and 3-19% grain yield increments compared to the control (no N) and previous recommendation (18 kg N ha À1 ), respectively with no detrimental effect on kernel protein concentrations. Seeding malting barley at a rate of 54 kg N ha À1 gave 250-915% increase in economic benefit. Use of break crops other than barley and increasing the rate of N application from 18 to 54 kg ha À1 have been recommended to boost malting barley yield without surpassing the acceptable range of kernel protein concentrations, reduce costs of production, increase profitability and improve soil fertility to enhance long-term sustainability of the cropping system.

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