[01] Dereje Dobocha, Agronomy and Crop Physiology Program, Ethiopian Institute of Agricultural Research, Kulumsa Agricultural Research Center, Asella, Ethiopia. [02] Wegayehu Worku, Agronomy and Crop Physiology Program, Ethiopian Institute of Agricultural Research, Kulumsa Agricultural Research Center, Asella, Ethiopia. [03] Fasil Shimeles, Agronomy and Crop Physiology Program, Ethiopian Institute of Agricultural Research, Kulumsa Agricultural Research Center, Asella, Ethiopia. [04] Zenebe Mulatu, Agronomy and Crop Physiology Program, Ethiopian Institute of Agricultural Research, Kulumsa Agricultural Research Center, Asella, Ethiopia. [05] Almaz Admasu, Agronomy and Crop Physiology Program, Ethiopian Institute of Agricultural Research, Kulumsa Agricultural Research Center, Asella, Ethiopia. [06] Debela Bekele, Agronomy and Crop Physiology Program, Ethiopian Institute of Agricultural Research, Kulumsa Agricultural Research Center, Asella, Ethiopia.

Detecting optimum plant density is one of the important agronomic practices to improve the production and productivity of malt barley varieties. Therefore, this study was initiated to determine the right plant densities to advance the production and productivity of malt barley varieties in Lemu-Bilbilo district, highlands of Arsi zone, Southeastern Ethiopia on two farmers’ fields during 2017 main cropping season. The treatments studied include three malt barley varieties (Bekoji1, EH1847 and Travler) assigned to main plot and six plant densities (D1 = 100 plants m^-2, D2 = 200 plants m^-2, D3 = 300 plants m^-2, D4 = 400 plants m^-2 and D5 = 500 plants m^-2 and D6= Recommended seed rate of 100 kg ha^-1 (as a control) assigned to sub-plot. The experiments were carried out in randomized complete block design in split plot arrangement with three replications. The results revealed most of the studied agronomic parameters significantly affected by the main as well as the interaction effect of varieties and plant densities at both experimental fields. Travler was the dwarf variety when compared with Bekoji1 and EH1847 varieties. Increasing plant densities resulted in decreased spike length even though the increment was inconsistent for Travler variety. The promising yield was gained from the combination of Travler with control, Bekoji1 and EH1847 with D3, but the yields of two varieties statistically at par with control seed rate at field 1 whereas from EH1847 and Travler at D4, Bekoji1 at D2, but didn’t show significant with the yield obtained from control at field 2. The highest value of harvest indexes were noted from Travler and EH1847 sown with D1 while statisticaly at par with control whereas for Bekoji1 at control. The heavier and lighter 1000-kernels weight (51.15 g, 44.92 g) were gained at D1 and D5, respectively. Moreover, the above ground dry biological yield difference of EH1847 at D4, Travler at D5 and control showed non-significant at field 1 whereas between Bekoji1 at D4, EH1847 at D5 and control at field 2. Thus, in view of the present study findings seed rate of 100 kg ha^-1 can be suggested for the production and productivity of EH1847 and Travler malt barley varieties at the experimental fields and similar agro ecologies.

Malt Barley, Plant Densities, Varieties, Yield and Yield Components

[01] Bogale, A. A., Niguse, K., Wasae, A., & Habitu, S. (2021). Response of Malt Barley (Hordeum Distichum L) Varieties to Different Row Spacing under Contrasted Environments of North Gondar, Ethiopia. International Journal of Agronomy, 2021. [02] AMF (Assela Malt Factory). (2012). Current annual beer production capacity and malt requirement of Ethiopian breweries 2012/2013. Assela, Ethiopia. [03] EBCIP (Ethiopia-Barley-Business-Case Investor Presentation). (2012). The Business Case for Investing in Malting Plant in Ethiopia, Investor Presentation. Addis Ababa, Ethiopia. [04] FAO (Food and Agriculture Organization). (2014). Food Balance Sheets. FAOSTAT Rome. [05] IGC (International Grains Council). (2013). five-year global supply and demand projections. 10 December 2013. [06] Hameed, E., Shah, W. A., Shad, A. A., Bakht, J., & Muhammad, T. (2003). Effect of different planting dates, seed rate and nitrogen levels on wheat. Asian Journal of Plant Sciences. [07] Geleta, B., Atak, M., Baenziger, P. S., Nelson, L. A., Baltenesperger, D. D., Eskridge, K. M.,... & Shelton, D. R. (2002). Seeding rate and genotype effect on agronomic performance and end-use quality of winter wheat. Crop Science, 42 (3), 827-832. [08] McKenzie, R. H., Middleton, A. B., & Bremer, E. (2005). Fertilization, seeding date, and seeding rate for malting barley yield and quality in southern Alberta. Canadian Journal of Plant Science, 85 (3), 603-614. [09] Edney, M. J., O’Donovan, J. T., Turkington, T. K., Clayton, G. W., McKenzie, R., Juskiw, P.,... & May, W. (2012). Effects of crop management on barley quality and endosperm modification during malting. J. Sci. Food Agric, 92, 2672-2678. [10] O'Donovan, J. T., Anbessa, Y., Grant, C. A., Macleod, A. L., Edney, M. J., Izydorczyk, M. S., & Chapman, W. (2015). Relative responses of new malting barley cultivars to increasing nitrogen rates in western Canada. Canadian Journal of Plant Science, 95 (5), 831-839. [11] Stevens, W. B., Sainju, U. M., Caesar-TonThat, T., & Iversen, W. M. (2015). Malt barley yield and quality affected by irrigation, tillage, crop rotation, and nitrogen fertilization. Agronomy Journal, 107 (6), 2107-2119. [12] Carr, P. M., Horsley, R. D., Martin, G. B., & Hochhalter, M. R. (2014). Malt barley cultivar ranking under long-term tillage systems in a semiarid region. Agronomy Journal, 106 (6), 2067-2074. [13] O’Donovan, J. T., Clayton, G. W., Harker, K. N., Turkington, T. K., & Lupwayi, N. Z. (2009). Relationship between seeding rate and plant density of hulled and hull-less barley as influenced by seeding depth in a no-tillage system. Canadian journal of plant science, 89 (4), 645-647. [14] O'Donovan, J. T., Turkington, T. K., Edney, M. J., Clayton, G. W., McKenzie, R. H., Juskiw, P. E.,... & May, W. E. (2011). Seeding rate, nitrogen rate, and cultivar effects on malting barley production. Agronomy Journal, 103 (3), 709-716. [15] Wade, A., & Froment, M. A. (2003). Barley Quality and Grain Size Homogeneity for Malting: Agronomic Effects on Varieties. HGCA. [16] Kavitha, G., Dhindsa, G. S., Singh, S. A. R. V. J. E. E. T., & Singh, J. O. H. A. R. (2009). Stability analysis of yield and its components in malt barley (Hordeum vulgare L.) genotypes. Crop Improvement, 36 (1), 29-34. [17] Amanuel, G., Kühne, R. F., Tanner, D. G., & Vlek, P. L. G. (2000). Biological nitrogen fixation in faba bean (Vicia faba L.) in the Ethiopian highlands as affected by P fertilization and inoculation. Biology and fertility of soils, 32 (5), 353-359. [18] Dobocha, D., Abera, G. and Worku, W, (2019). Grain quality and nitrogen use efficiency of bread wheat (Triticum aestivum L.) varieties in response to nitrogen fertilizer in Arsi highlands, southeastern Ethiopia. African Journal of Agricultural Research, 14 (32), pp. 1544-1552. [19] Bowman, D. C. and J. M. Lees, (2013). The Hilbert-Huang transform: Tools and methods. R Version, 2.1.3, pp: 05-16. [20] Kefale, B. G. D., & Hawassa, E. (2016). Effect of nitrogen fertilizer level on grain yield and quality of malt barley (Hordeum vulgare L.) varieties in malga woreda, southern ethiopia. [21] Shahzad, M. A., Sahi, S. T., Khan, M. M., & Ahmad, M. (2007). Effect of sowing dates and seed treatment on grain yield and quality of wheat. Pakistan Journal of Agricultural Sciences (Pakistan). [22] Jemal, A., Tamado, T., & Firdissa, E. (2015). Response of bread wheat (Triticum aestivum L.) varieties to seeding rates at Kulumsa, south eastern Ethiopia. Asian Journal of Plant Sciences, 14 (2), 50-58. [23] ABEBE, A. (2018). EFFECTS OF BLENDED FERTILIZER RATES ON GROWTH, YIELD AND QUALITY OF MALT BARLEY (Hordeum distichum L) VARIETIES AT DEBRE BERHAN DISTRICT CENTRAL HIGH LAND OF ETHIOPIA (Doctoral dissertation). [24] Lake Mekonnen. (2018). Effects of Seed and N Rate on Grain Yield and Yield Components of Barley. Journal of Natural Sciences Research, 8: 3. [25] Abdoli, M., & Saeidi, M. (2012). Effects of water deficiency stress during seed growth on yield and its components, germination and seedling growth parameters of some wheat cultivars. International Journal of Agriculture and Crop Sciences, 4 (15), 1110-1118. [26] Whaley, J. M., Sparkes, D. L., Foulkes, M. J., Spink, J. H., Semere, T., & Scott, R. K. (2000). The physiological response of winter wheat to reductions in plant density. Annals of Applied Biology, 137 (2), 165-177. [27] Kiliç, H., & Gürsoy, S. (2010). Effect of seeding rate on yield and yield components of durum wheat cultivars in cotton-wheat cropping system. Scientific Research and Essays, 5 (15), 2078-2084. [28] Muhammad, R. W., Qayyum, A., Liaqat, S., Hamza, A., Yousaf, M. M., Ahmad, B., & Noor, E. (2012). Variability, heritability and genetic advance for some yield and yield related traits in barley (Hordeum vulgare L.) genotypes in arid conditions. Journal of Food, Agriculture & Environment, 1 0 (3&4), 626-629. [29] Ibeawuchi, I. I., Matthews-Njoku, E., Ofor, M. O., Anyanwu, C. P., and Onyia, V. N. (2008). Plant spacing, dry matter accumulation and yield of local and improved maize cultivars, Journal of American Science, vol. 4, no. 1, pp. 545–1003. [30] Das, T. K., & Yaduraju, N. T. (2011). Effects of missing-row sowing supplemented with row spacing and nitrogen on weed competition and growth and yield of wheat. Crop and Pasture Science, 62 (1), 48-57. [31] Bhowmik, S. K., Sarkar, M. A. R., & Zaman, F. (2012). Effect of spacing and number of seedlings per hill on the performance of aus rice cv. NERICA 1 under dry direct seeded rice (DDSR) system of cultivation. Journal of the Bangladesh Agricultural University, 10 (452-2016-35674), 191-195. [32] Fox, G. P., Kelly, A., Poulsen, D., Inkerman, A., & Henry, R. (2006). Selecting for increased barley grain size. Journal of Cereal Science, 43 (2), 198-208. [33] Jairus, O. J., Auma, P. E. O., & Ngode, D. L. (2015). Evaluation of promising malting barley varieties using agronomic and quality traits in Kenya. J Agri Life Sci, 2 (1), 104-110. [34] Aynewa, Y., Dessalegn, T., & Bayu, W. (2013). Participatory evaluation of malt barley (Hordeum vulgare L.) genotypes for yield and other agronomic traits at North-West Ethiopia. Wudpecker Journal of Agricultural Research, 2 (8), 218-222. [35] Bishaw, Z., Struik, P. C., & Van Gastel, A. J. (2014). Assessment of on-farm diversity of wheat varieties and landraces: Evidence from farmers’ fields in Ethiopia. African Journal of Agricultural Research, 9 (39), 2948-2963. [36] Abebe, M., Anbessie, A. D., & Dechassa, H. (2020). Effect of Plant Population on Growth, Yields and Quality of Bread Wheat (Triticum Aestivum L.) Varieties at Kulumsa in Arsi Zone, South-Eastern Ethiopia. International Journal of Research Studies in Agricultural Sciences (IJRSAS), 6 (2), 32-53. [37] Donald, C. M., & Hamblin, J. (1976). The above ground dry biological yield and harvest index of cereals as agronomic and plant breeding criteria. Advances in agronomy, 28, 361-405.