Abstract :
This experiment was conducted as split plot based on randomized complete block design with 3 replications during 2013-2014 at the Research and Experimental Field of Islamic Azad University in Ahvaz, Iran. The main plots consisted of three cultivars of barley (Jonoob, Nimrooz, and Zahak) and subplots of plant density with four levels (250, 300, 350, and 400 seeds/m2). Results showed that increasing seed density increased leaf area index (LAI), crop growth rate (CGR), and decreased net assimilation rate (NAR) in all of the cultivars under study. The Jonoob cultivar had the highest (LAI), (CGR), and (NAR). The differences among cultivars in number of spikes/m2, seed number per spike, length of spike and seed yield were significant at %1 and harvest index at the 5% levels of probabilities. The effects of seeding rates on spike length, spike number, seed number per spike, seed yield and stem length were significantly at 1% and, biological yield and harvest index at 5% levels of probabilities. The highest seed yield was produced by Jonoob cultivar by using 350 seeds/m2 (5,561 kg/ha), The Maximum harvest index was obtained in Jonoob cultivar at the rate 350 seeds/m2 (40%). The results showed that the Jonoob cultivar, because of higher physiological indices and yield components (spike length, seed weight and number of grains per spike) and seeding density of 350 and 400 seeds/m2 by increasing number of spikes/m2, produced higher yield.
References:
Ahmadi, A., T. Hosseinpour, and M. Soltani. 2012. The effect of plant density on yield and itscomponents in three rain fed barley cultivars. Journal of Agriculture (Pajouhesh & Sazandegi). 102: 131-140. (In Persian).
Armin, M., G. Noormohammadi, E. Zand, M. Baghestani, and F. Darvish. 2008. Study on some ecophysiological difference in more and less competitive winter wheat cultivars on competition with wild oat at different wheat densities. Journal of Pajouhesh & Sazandegi. 80: 119-127.
Bahrani, M., and A. Seyyedi. 2005. The effect of plant density and nitrogen application methods on corn yield and its components. Journal of Agricultural Sciences and Natural Resources. 3: 128-135. (In Persian).
Bakema-Boomstra, A.G., and H.D. Masterbroke. 1993. The grain yield of uniculm barley (Hordeum vulgare L.) in two contrasting environments. Euphytica. 66: 103-110.
Bakhshandeh, A., and A. Rahnama. 2005. The effect of seeding rates, planting date on the tiller, yield six cultivars. Journal of Agricultural Sciences and Natural Resources. 3: 31-42. (In Persian).
Bavar, M. 2008. Effects of planting date density on growth indecies and yield component of hull-less barley. The Thesis of M.Sc. degree. University of Agriculture Sciences and Natural Resources of Gorgan, 62 p.
Dehghani, H., A. Ebadi and A. Yousefi. 2006. Biplot analysis of genotype by environment interaction for barley yield in Iran. Agronony Journal. 98: 388-393.
Donaldson, E., W.F. Schillinger, and S.M. Dofing. 2001. Straw production and grain yield relationships in winter wheat. Crop Sci. 41: 100-106.
Falah heravi, A., N. Ltyfy, and S. Galshy. 2002. The effect of planting and seeding density on yield and yield components of wheat. Journal of Agricultural Science and Technology. 2(2) 103-112. (In Persian).
Farnia, A., A. Aminbaygi, and A. Niazi Fard. 2014. The effect of plant density on comparison forage yield of spring barley cultivar. International Journal of Farming and Allied Sciences. L: 244-250. (In Persian).
Fathi, G.H. 2005. Effects of planting pattern and population density on light extinction coefficient, light interception and grain yield of sweet corn (Hybrid SC 704). Journal of Agricultural Sciences Nature and Resourse. 12: 131-143. (In Persian).
Fathi, G.A., A. Alipour, M. Radmehr, and A. Lotfali ayendh. 1998. Interaction of density and nitrogen fertilizer on yield and yield components south of Varamin Agricultural Educational Center martyr Chamran University, Center for Agricultural Research in Khuzestan. Proceedings of the Sixth Congress of Crop Iran, Babolsar, Mazandaran University. (In Persian).
Fischer, R.A. 1999. Irrigated spring wheat and timing and amount of nitrogen fertilizer. Field Crops Res. 33: 57-80.
Halloran, G.M. 1981. Grain yield and protein relation ship a wheat cross. Grape. Sci. 21: 699-701.
Hashemi–Dezfouli, A., and S.J. Herbert. 1992. Effect of leaf orientation and density on yield of corn. Iran Agric. Res. 11:89 –104. (In Persian).
Hashemi Dezfouli, A., A. Kocheki, and M, Banaian Aval. 1997. Maximizing crop yield. Mashhad Jahad Daneshgahi Publication. (In Persian).
Hemmat, A., and O. Taki. 2001. Grain yield of irrigation winter wheat as affected by tillage management and seeding rates in central Iran. Soil Tillage Res. 63: 57–64. (In Persian).
Imam, Y. 2007. The cultivation of crops, Third Edition, Publishing Center, Shiraz University, pages 196. (In Persian).
Innes, P., R.D. Blackwell, and R.B. Austin. 1981. The effects of selection for number of ears on the yield and water economy of winter wheat. J. Agric. Sci. Comb. 97: 523 – 532
Jaafari Haghighi, B., R. Mamaghani, A. Kashani, and S.A. Siadat. 2002. Effect of plant density on grain yield and some qualitative characteristics of five durum wheat genotypes under Ahvaz climatic conditions. Iranian Journal of Crop Sciences. 4(1): 67-79. (In Persian).
Jasemi, S., and A. Yousefi. 2004. The effect of seeding rate on yield and hull-less barley lines. Proceedings of the Eighth Congress of Crop Sciences, the University of Guilan. (In Persian).
Javadi, H., M.H. Rashed Mohasel, Gh.R. Zamani, E. Azari Nasr Abadi, and Gh.R. Musavi. 2007. Effect of plant density on growth indices in four grain sorghum cultivars. Iranian J. Field Crops Res. 4: 265 – 253. (In Persian).
Keshiri, M., N. Latifi, and M. Ghasemi. 2003. Growth analysis of safflower varieties with different cropping pattern in rainfed condition. Agri. Natur. Resour. 10: 85-94. (In Persian).
Khayam, S., D. Mazaheri, M. Banayan aval, J. Gohari, and M. Jahansooz. 2002. Determination of sugar beet extinction coefficient and radiation use efficiency at different plant density and nitrogen use levels sugar beet. Sugar beet.Vol, 18(1): 51-66. (In Persian).
Koochaki, A., and J. Khalghani. 1997. Understanding crop production. Fersowsi University of Mashhad Press. 260p. (In Persian).
Lak, S., A. Modhej, M. Moghadam, M. Alavi Fazel, A. Sadeghi Pour, and K. Seyed Javadi. 2009. The effect of genotype and plant density on yield and grain dual purpose, Quarterly Journal of Plants and Ecosystems.18: 25-43. (In Persian).
Nazari, H.R. 2011. The effect of planting date and plant density on yield and its components in the cold Region Aligudarz. New Science of Sustainable Agriculture. 7(3): 64-75. (In Persian).
Niknam, N., and H. Faraji. 2014. Effect of plant density and nitrogen on corn yield 704. Publication Agriculture (Research and Development). 102: 55-60. (In Persian).
Ouzuni Douji, A.A., M. Esfahani, H.A. Samizadeh Lahiji, and M. Rabiei. 2008. Effect of planting pattern and plant density on growth indices and radiation use efficiency of apetalous flowers and petalled flowers rapeseed (Brassica napus L.) cultivars. Iranian J. Crop Sci. 9: 400–328. (In Persian).
Power, J.F., W.O. Willis, D.L. Grunes, and G.A. Reichman. 1976. Effect of soil temperature, phosphorus, and plant age growth, analysis of barley. Agron. J. 59: 231 –234.
Rashed Mohassel, M.H., and A. Koockaki. 1990. Principles of dry farming (translated). Mashhad Jahad University Pub. Iran. (In Persian).
Sabet Moghadam. H. 2009. Effect of planting date and seeding density on grain yield and yield components on hulls barley in Ahvaz region. In: Gh. Fathi, A. Siadat (Eds), Proceeding of Agronomy and Plant Breeding Congress. 503 pp. Karaj, Tehran. (In Persian).
Safari, F., S. Galeshi, N. Torbati Nejad, and S.A. Mosavat. 2008. Effect of planting date and plant density on yield of foxtail millet. Journal of Agricultural and Natural Resources. Volume Issue Special Crop fifth. 5(15) 22-36. (In Persian).
Sarmad Nia, Gh., and A. Koochaki. 1993. Agricultural plants physiology (translation). Jahad Daneshgahi Publication of Mashhad. Third edition, pp. 116-210. (In Persian).
Shakeri, S., A. Naderi, and A. Lakzadeh. 2009. Effects of planting and seeding rate on yield and yield components of two genotypes in Ahvaz weather conditions. Msc. Islamic Azad University, Science and Research Khuzestan. (In Persian).
Sharifi, R., P. Khanghah, and Y. Raee. 2013. Effect of plant density on yield, yield components and other physiological indicators of three chickpea cultivars. Journal of Crop Physiology. 5(20): 38-25.
Soleymani, A., M.H. Shahrajabian, and L. Naranjani. 2011. Determination of the suitable date and plant density for different cultivars of barley (Hordeum vulgare L.) in Fars. African Journal of Plant Science. 5(3): 284 -286. (In Persian).
Soleymanifard, A., S.S. Pourdad, R. Naseri, and A. Mirzaei. 2011. Effect of planting pattern on phonological characteristics and growth indices of safflower (Carthamus tinctoriu L.) in rainfed conditions. Iranian Journal of Crop Sciences. 13(2): 282-298. (In Persian).
Taghavi, D., G. Noormohamadi, and A. Valadiani. 2007. Effect of plant density on yield and some morphological characters of some sunflower (Helianthus annuus L.) cultivars. Journal of Crop Iran. 2(1): 1-14. (In Persian).
Tajbakhsh, M., and A. Pourmirza. 2003. Cultivation of crops. University of West Azarbaijan. 312 page. (In Persian).
Tetio-Kagho, F., and F.P. Gardner. 1988. Responses of maize to plant population density. Reproductive development, yield and yield adjustment. Agron. J. 80: 935 - 940.
Turk, M.A., M. Abdel Rahman, A. Tawaha, O. Niksun, and M. Rifaee. 2003. Response of sixrow barley to seeding rate with or without ethrel spray in the absence of moisture stress. International Journal of Agriculture and Biology. 5(4): 416-427. (In Persian).
Ying, J., Sh. Peng, Q. He, H. Yang, Ch. Yang, R.M. Visperas, and K.G. Cassman. 1998. Comparison of high- yield rice in a tropical and subtropical environment: I. Determinants of grain and dry matter yields. Field Crops Res. 57: 71-84.
Zndvakili, A., M. Shahbazi, H. Nickhah, and S. Sanjari. 2011. Evaluation of drought tolerance region cultivars and commercial collections. Plant Physiology Conference on Iran, Yazd University. (In Persian).