اثر ماده کندکننده رشد کلرمکوات کلراید و سطوح کود نیتروژن بر برخی صفات فیزیولوژیک، بیوشیمیایی و عملکرد جو رقم ماکویی (Hordeum vulgare L.)
محورهای موضوعی : ژنتیک
1 - گروه فیزیولوژی گیاهی، واحد کلیبر، دانشگاه آزاد اسلامی، کلیبر، ایران.
2 - گروه زیست شناسی، واحد اردبیل، دانشگاه آزاد اسلامی، اردبیل، ایران.
کلید واژه: کلروفیل, پروتئین, آنزیمهای آنتیاکسیدان, محتوای نسبی آب, سایکوسل,
چکیده مقاله :
بهمنظور بررسی اثر غلظتهای مختلف کلرمکوات کلراید و سطوح محتلف کود نیتروژن بر برخی صفات فیزیولوژیک، بیوشیمیایی و عملکرد جو رقم ماکویی آزمایشی در بهار سال زراعی 1394 بهصورت فاکتوریل در قالب طرح پایه بلوکهای کامل تصادفی در 4 تکرار اجرا شد. تیمارهای آزمایش شامل غلظتهای کلرمکوات کلراید (صفر، 500، 1000 و 1500 میلیگرم در هکتار) و نیتروژن در 3 سطح (50 ، 100 و 150 کیلوگرم در هکتار) بود. نتایج تحقیق نشان داد که اثر برهمکنش کلرمکوات کلراید و کود نیتروژنه بر میزان کلروفیل، محتوی رطوبت نسبی، عملکرد و درصد پروتئین، فعالیت آنزمهای سوپراکسید دیسموتاز و کاتالاز در سطح احتمال خطای یک درصد و روی تعداد دانه در هر سنبله، وزن هزار دانه و فعالیت آنزم گلوتاتیون پراکسیداز در سطح احتمال خطای پنج درصد معنیداری است. افزایش مصرف میزان کود نیتروژنه سبب کاهش محتوی نسبی آب برگ به دلیل کاهش پتانسیل آب برگ گردید. کلرمکوات کلراید با انتقال مواد فتوسنتزی کافی به دانهها در پر شدن آنها و افزایش وزن دانهها نقش به سزایی دارد. افزایش مصرف میزان غلظت کلرمکوات کلراید و فراهمی نیتروژن موجب کاهش فعالیت آنزیمهای سوپراکسید دیسموتاز، کاتالاز و گلوتاتیون پراکسیداز شده است. بهطور کلی، در این پژوهش بیشترین میزان کلروفیل، محتوای رطویت نسبی، اجزای عملکرد، عملکرد و درصد پروتئین از کاربرد تیمار 1500 میلیگرم در هکتار کلرمکوات کلراید و 150 کیلوگرم در هکتار نیتروژن بهدست آمد.
To study the effects of different concentrations of chlormequat chloride and different levels of nitrogen on some physiological and biochemical characteristics and yield of barley (Hordeum vulgare L.) cultivar makuyi a factorial randomized complete block design was used with 4 replications in spring 2015. Treatments included chlormequat chloride concentrations (0, 500, 1,000, and 1500 mg/ha) and nitrogen at 3 levels (50, 100, and 150 kg/ha). Results suggest a significant difference between interaction effects of chlormequat chloride and nitrogen fertilizer on chlorophyll content, relative water content, yield and protein percentage, and activity of superoxide dismutase and catalase enzymes at 1% probability level and in the number of seeds per spike, 1000 seed weight, and glutathione peroxidase enzyme activity at 5% probability level. An increase in the consumption of nitrogen fertilizer decreased the relative water content of leaves due to reduced leaf water potential. Chlormequat chloride by transferring sufficient photosynthetic material to the seeds played an important role in their filling and increased seed weight. Also, the activities of superoxide dismutase, catalase, and glutathione peroxidase enzymes were decreased by increasing the consumption of chlormequat chloride concentration and nitrogen uptake. In general, through applying 1500 mg/ha chlormequat chloride and 150 kg/ha nitrogen, the highest chlorophyll content, relative water content, yield components, yield, and protein percent were obtained.
Agarwal, S., Sairam, R.K., Srivatava, G.C. and Meena, R.C. (2005). Changes in antioxidant enzymes activity and oxidative stress by abscisic acid and salicylic acid in wheat genotypes. Biologia Plantarum. 49(4): 541-550.
Ahmadpour, R., Hosseinzadeh, S.R. and Chashiani, S. 2016. Study of root morpho-physiological and biochemical characteristics of lentil (Lens culinaris Medik.) in response to moisture stress. Journal of Irainian Plant Ecophysiological Research (Plant Sciences Research). 11(43): 39-51. (In Persian with English abstract).
Akbari, V., Jalili Marandi, R., Khara, J. and Farrokhzad, A.R. (2015). The response two varieties of olive Mary and Mission to CCC treatment under drought stress. Iranian Horticultural Science 46(2): 213-223 [in Persian with English abstract].
Bahadoran, M., Abrishamchi, P., Ejtehadi, H. and Ghassemzadeh, F. (2015). Study on some physiological characteristics of Salsola richteri in drought condition in the two desert regions of the South Khorasan province. Plant Biology. 7(24): 1-14. (In Persian with English abstract).
Beauchamp, C. and Fridovich, I. (1971). Superoxide dismutase: improved assays and applicable to acryl amide gels. Annual Review of Biochemistry. 44: 276-287.
Beheshti, A. and Behboodi, B. (2010). Dry matter accumulation and remobilization in grain sorghum genotypes (sorghum bicolor L.) Monech) under drought stress condition. Crop Science. 4: 185-189.
Bly, A.G. and Woodward, H.J. (2003). Foliar nitrogen application timing: Influence on grain yield and grain protein concentration of hard red spring wheat. Agronomy Journal 95: 335–338.
Burton, J.D., Pedersen, M.K. and Coble, H.D. 2008. Effect of cyclanilide on auxin activity. Journal of Plant Growth Regulation 27: 342-352.
Chandlee, J.M. and Scandalios, J.G. (1984). Analysis of variants affecting the plants. Plant Nutrition Soil Science. 168: 541-549.
Chen, W.P., Li, P.H. and Chen, T.H.H. (2000). Glycinebetaine increases chilling tolerance and reduces chilling induced lipid peroxidation in Zea mays L. Plant Cell Environment. 23: 609-618.
Dat, J., Vandenabeele, S., Vranova, E., Van Montagu, M., Inze, D. and Van Breusegem, F. )2000(. Dual action of the active oxygen species during plant stress responses. Cellular and Molecular Life Sciences. 57: 779–795.
Dixon, D.P., Cummins, I., Cole, D.J. and Edwards, R. )1998(. Glutathione-mediated detoxification systems in plants. Current Opinion in Plant Biology. 1: 258–266.
Dordas, C.A. and Sioulas, C. (2008). Safflower yield, chlorophyll content, photosynthesis, and water use efficiency response to nitrogen fertilization under rain fed conditions. Field Crops Res. 27: 75-85.
Ebadi.A., Sajed, K. and Asgari, R. (2007). Effects of water deficit on dry matter remobilization and grain filling trend in three spring barley genotypes. Journal of Food Agriculture Enviroment. 5: 359-362.
Espidkar, Z., Yarnia, M., Ansari, M., Mirshekari, B. and Asadi Rahmani, H. (2016). Effect of mycorrhiza fungi on ecophysiological characteristics of barley cultivars in response to inoculation with different strains of Pseudomonas fluorescence under rain fed conditions. Crop Physiology Journal. 8(30): 21-38. (In Persian with English abstract).
Hamrahi, S., Habibi, D., Madani, H. and Mashhadi Akbar Boojar, M. (2008). Effect of cycocel and micronutrients on antioxidants rates as indices of drought resistance of rapeseed. New Finding Agriculture. 2(3): 316-329. (In Persian with English abstract).
Hatamvand, M., Hasanloo, T., Dehghan Nayeri, F., Shiranirad, A.H., Ali Tabatabaei, S. and Mohammad Hosseini, S. (2015). Evaluation of some physiological and biochemical indices of canola in response to drought stress. Enviromental Stresses in Crop Science. 7(2): 173-185. (In Persian with English abstract).
Hokmalipour, S. and Seyed Sharifi, R. (2014). Effect of Seed Inoculation with Plant Growth Promoting Rhizobacteria (PGPR) Affected by Different Levels of Nitrogen and Phosphorus Fertilizers on the Yield and Some Physiological Parameters of Barley. Iranian Journal of Field Crops Research. 12(4): 822-833. (In Persian with English abstract).
Holy, M.C. (1972). Indole acetic acid oxidase: a dual catalytic enzyme. Plant Physiology. 50: 15-18.
Jiriaie, M., Sajedi, N.A., Madani, H. and Sheikhi, M. (2009). Effect of PGPR and water deficit on agronomical traits of wheat (cv. Shahriar). Scientific Journal Database. 3(4): 333-343. (In Persian with English abstract).
Khalilzadeh, R., Seyed Sharifi, R. and Jalilian, J. (2016). Antioxidant status and physiological responses of wheat (Triticum aestivum L.) to cycocel application and bio fertilizers under water limitation condition. Journal of Plant Interaction. 11(1): 130-137.
Lin, T., Zhu, X. and Zhang, F. )2012(. The Interaction effect of cadmium and nitrogen on Populus yunnanensis. Journal Agriculture Science. 4 (2):125-134.
Logan, B.A., Demmig-Adams, B., Rosenstiel, T.N. and Adams, W.W. )1999(. Effect of nitrogen limitation on foliar antioxidants in relationship to other metabolic characteristics. Planta. 299: 213–220.
Merajipour, M., Movahhedi Dehnavi, M., Baluchi, H. and Merajipour, M. (2014). Effect of cycocel on safflower seed yield and oil at different levels of nitrogen and plant density. Crop Production. 6(3): 163-180. (In Persian with English abstract).
Mirzaii Abdolyosefi, A.A., Jafari Haghighi, B. and Emam, Y. )2011(. Effect of planting density and chlormequat chloride on growth and yield of wheat (Triticum aestivum var Cross Azadi). Journal of Plant Physiology. 3(8): 1-15. (In Persian with English abstract).
Modhej, A., Naderi, A., Emam, Y., Aynehband, A. and Normohamadi, G. )2008(. Effects of post-anthesis heat stress and nitrogen levels on grain yield in wheat (T. durum and T. aestivum) genotypes. International Journal of Plant Production. 2(3): 257-268. (In Persian with English abstract).
Mojadam, M., Sakinezhad, T., Shokoohfar, A. and Esmailipour, N. (2016). Effect of plant density and cycocel on quantitative characteristics and protein barley cultivar south. Crop Physiology Journal. 8(29): 121-135. (In Persian with English abstract).
Molodi, A., Ebadi, A. and Davari, M. (2015). Effect of nitrogen application on dry matter and nitrogen remobilization of spring barley under water deficit conditions. Crop Production. 8(3): 95-114. (In Persian with English abstract).
Movahhedi Dehnavi, M., Ranjbar, M., Yadavi, A.R. and Kavusi, B. (2010). Effect of cycocel on proline, soluble sugars, protein, oil and fatty acids of Linum Usitatissimum L plants under drought stress in a pot trial. Journal of Environmental Stresses in Crop Sciences. 2(3): 129-138. (In Persian with English abstract).
Peng, S., Sanico, A.L., Grrcia, F.V., Laza, R.C., Visperas, R.M., Descalsota, J.P. and Cassman, K. (1999). Effect of leaf phosphorus and potassium concentration on chlorophyll meter reading in rice. Plant Prodction. Science. 2: 227-231.
Pirasteh-Anosheh, H. and Emam, Y. (2012). Yield and yield components responses of bread and wheat to PGRs under stress conditions in field and greenhouse. Environmental Stress in Crop Science. 5: 1-18.
Radmehr, M., Lotfali-Ayeneh, A. and Mamaghni, R. (2005). A study of the reaction of middle, long and short season wheat genotypes to different sowing dates. Seed and Plant. 21(2): 175-189.
Rajala, A. 2004. Plant growth regulators to manipulate oat stands. Agriculture and food Science in Finland. 13:186-197.
Seyed Sharifi1, R. and Namvar, A. (2016). Plant density and intra-row spacing effects on phenology, dry matter accumulation and leaf area index of maize in second cropping. Biologija. 62(1): 46-57.
Sharif, S., Saffari, M. and Emam, Y. (2007). The effect of drought stress and cycocel on barley yield (Cv. Valfajr). Journal of Water and Soil Science (Science and Technology of Agriculture and Natural Resources). 10 (4) :281-291. (In Persian with English abstract).
Shekoofa, A. and Emam, Y. (2008). Effects of nitrogen fertilization and plant growth regulators (PGRs) on yield of wheat (Triticum aestivum L.) cv. Shiraz. Agricultural Science and Technology. 10, 101-108.
Sivritepe, N., Sivritepe, H.O. and Turkben, C. (2008). Determination of moisture content in grape seeds. Seed Science and Technology. 36: 198-200.
Subedi, K.D., Ma, B.L. and Xue, A.G. (2007). Planting date and nitrogen effects on grain yield and protein content of spring wheat. Crop Science. 47:36-44.
Taghizadeh, R. and Seyed Sharifi, R. (2011). Effect of nitrogen fertilizer on yield attributes and nitrogen use efficiency in corn cultivars. Journal of Water and Soil Science. 15(57): 209-217. (In Persian with English abstract).
Varvel, G.E., Schepers, J.S., and Francis, D.D. (1997). Ability for in season correction of nitrogen deficiency in corn using chlorophyll meters. Soil Science Journal. 61: 1233-1239.
Verma, K.K., Singh, M., Gupta, R.K. and Verma, C.L. (2014). Photosynthetic gas exchange, chlorophyll fluorescence, antioxidant enzymes and growth responses of Jatropha curcas during soil flooding. Turkish Journal of Botany. 38: 130-40.
Voltas, J., Romagosa, I. and Araus, J. L. (1997). Grain size and nitrogen accumulation in sink-reduction barley under Mediterranean conditions. Field Crops Research. 52: 117-126.
Wang, H., Li, Q., Liu, H.S. and Xiao, L.T. (2009). Chlorocholine chloride application effects on photosynthetic capacity and photoassimilates partitioning in potato (Solanum tuberosum L.). Scientia Horticulturae. 119: 113-116.
Yusefzadeh, M. Daneshvar, M. Shahrvasvand, S. and Sorkhe, H. (2013). The effects of ethephon and nitrogen fertilizer on yield and yield components of sweet sorghum. Scientific Journal Database. 44(2): 199-207. (In Persian with English abstract).
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Agarwal, S., Sairam, R.K., Srivatava, G.C. and Meena, R.C. (2005). Changes in antioxidant enzymes activity and oxidative stress by abscisic acid and salicylic acid in wheat genotypes. Biologia Plantarum. 49(4): 541-550.
Ahmadpour, R., Hosseinzadeh, S.R. and Chashiani, S. 2016. Study of root morpho-physiological and biochemical characteristics of lentil (Lens culinaris Medik.) in response to moisture stress. Journal of Irainian Plant Ecophysiological Research (Plant Sciences Research). 11(43): 39-51. (In Persian with English abstract).
Akbari, V., Jalili Marandi, R., Khara, J. and Farrokhzad, A.R. (2015). The response two varieties of olive Mary and Mission to CCC treatment under drought stress. Iranian Horticultural Science 46(2): 213-223 [in Persian with English abstract].
Bahadoran, M., Abrishamchi, P., Ejtehadi, H. and Ghassemzadeh, F. (2015). Study on some physiological characteristics of Salsola richteri in drought condition in the two desert regions of the South Khorasan province. Plant Biology. 7(24): 1-14. (In Persian with English abstract).
Beauchamp, C. and Fridovich, I. (1971). Superoxide dismutase: improved assays and applicable to acryl amide gels. Annual Review of Biochemistry. 44: 276-287.
Beheshti, A. and Behboodi, B. (2010). Dry matter accumulation and remobilization in grain sorghum genotypes (sorghum bicolor L.) Monech) under drought stress condition. Crop Science. 4: 185-189.
Bly, A.G. and Woodward, H.J. (2003). Foliar nitrogen application timing: Influence on grain yield and grain protein concentration of hard red spring wheat. Agronomy Journal 95: 335–338.
Burton, J.D., Pedersen, M.K. and Coble, H.D. 2008. Effect of cyclanilide on auxin activity. Journal of Plant Growth Regulation 27: 342-352.
Chandlee, J.M. and Scandalios, J.G. (1984). Analysis of variants affecting the plants. Plant Nutrition Soil Science. 168: 541-549.
Chen, W.P., Li, P.H. and Chen, T.H.H. (2000). Glycinebetaine increases chilling tolerance and reduces chilling induced lipid peroxidation in Zea mays L. Plant Cell Environment. 23: 609-618.
Dat, J., Vandenabeele, S., Vranova, E., Van Montagu, M., Inze, D. and Van Breusegem, F. )2000(. Dual action of the active oxygen species during plant stress responses. Cellular and Molecular Life Sciences. 57: 779–795.
Dixon, D.P., Cummins, I., Cole, D.J. and Edwards, R. )1998(. Glutathione-mediated detoxification systems in plants. Current Opinion in Plant Biology. 1: 258–266.
Dordas, C.A. and Sioulas, C. (2008). Safflower yield, chlorophyll content, photosynthesis, and water use efficiency response to nitrogen fertilization under rain fed conditions. Field Crops Res. 27: 75-85.
Ebadi.A., Sajed, K. and Asgari, R. (2007). Effects of water deficit on dry matter remobilization and grain filling trend in three spring barley genotypes. Journal of Food Agriculture Enviroment. 5: 359-362.
Espidkar, Z., Yarnia, M., Ansari, M., Mirshekari, B. and Asadi Rahmani, H. (2016). Effect of mycorrhiza fungi on ecophysiological characteristics of barley cultivars in response to inoculation with different strains of Pseudomonas fluorescence under rain fed conditions. Crop Physiology Journal. 8(30): 21-38. (In Persian with English abstract).
Hamrahi, S., Habibi, D., Madani, H. and Mashhadi Akbar Boojar, M. (2008). Effect of cycocel and micronutrients on antioxidants rates as indices of drought resistance of rapeseed. New Finding Agriculture. 2(3): 316-329. (In Persian with English abstract).
Hatamvand, M., Hasanloo, T., Dehghan Nayeri, F., Shiranirad, A.H., Ali Tabatabaei, S. and Mohammad Hosseini, S. (2015). Evaluation of some physiological and biochemical indices of canola in response to drought stress. Enviromental Stresses in Crop Science. 7(2): 173-185. (In Persian with English abstract).
Hokmalipour, S. and Seyed Sharifi, R. (2014). Effect of Seed Inoculation with Plant Growth Promoting Rhizobacteria (PGPR) Affected by Different Levels of Nitrogen and Phosphorus Fertilizers on the Yield and Some Physiological Parameters of Barley. Iranian Journal of Field Crops Research. 12(4): 822-833. (In Persian with English abstract).
Holy, M.C. (1972). Indole acetic acid oxidase: a dual catalytic enzyme. Plant Physiology. 50: 15-18.
Jiriaie, M., Sajedi, N.A., Madani, H. and Sheikhi, M. (2009). Effect of PGPR and water deficit on agronomical traits of wheat (cv. Shahriar). Scientific Journal Database. 3(4): 333-343. (In Persian with English abstract).
Khalilzadeh, R., Seyed Sharifi, R. and Jalilian, J. (2016). Antioxidant status and physiological responses of wheat (Triticum aestivum L.) to cycocel application and bio fertilizers under water limitation condition. Journal of Plant Interaction. 11(1): 130-137.
Lin, T., Zhu, X. and Zhang, F. )2012(. The Interaction effect of cadmium and nitrogen on Populus yunnanensis. Journal Agriculture Science. 4 (2):125-134.
Logan, B.A., Demmig-Adams, B., Rosenstiel, T.N. and Adams, W.W. )1999(. Effect of nitrogen limitation on foliar antioxidants in relationship to other metabolic characteristics. Planta. 299: 213–220.
Merajipour, M., Movahhedi Dehnavi, M., Baluchi, H. and Merajipour, M. (2014). Effect of cycocel on safflower seed yield and oil at different levels of nitrogen and plant density. Crop Production. 6(3): 163-180. (In Persian with English abstract).
Mirzaii Abdolyosefi, A.A., Jafari Haghighi, B. and Emam, Y. )2011(. Effect of planting density and chlormequat chloride on growth and yield of wheat (Triticum aestivum var Cross Azadi). Journal of Plant Physiology. 3(8): 1-15. (In Persian with English abstract).
Modhej, A., Naderi, A., Emam, Y., Aynehband, A. and Normohamadi, G. )2008(. Effects of post-anthesis heat stress and nitrogen levels on grain yield in wheat (T. durum and T. aestivum) genotypes. International Journal of Plant Production. 2(3): 257-268. (In Persian with English abstract).
Mojadam, M., Sakinezhad, T., Shokoohfar, A. and Esmailipour, N. (2016). Effect of plant density and cycocel on quantitative characteristics and protein barley cultivar south. Crop Physiology Journal. 8(29): 121-135. (In Persian with English abstract).
Molodi, A., Ebadi, A. and Davari, M. (2015). Effect of nitrogen application on dry matter and nitrogen remobilization of spring barley under water deficit conditions. Crop Production. 8(3): 95-114. (In Persian with English abstract).
Movahhedi Dehnavi, M., Ranjbar, M., Yadavi, A.R. and Kavusi, B. (2010). Effect of cycocel on proline, soluble sugars, protein, oil and fatty acids of Linum Usitatissimum L plants under drought stress in a pot trial. Journal of Environmental Stresses in Crop Sciences. 2(3): 129-138. (In Persian with English abstract).
Peng, S., Sanico, A.L., Grrcia, F.V., Laza, R.C., Visperas, R.M., Descalsota, J.P. and Cassman, K. (1999). Effect of leaf phosphorus and potassium concentration on chlorophyll meter reading in rice. Plant Prodction. Science. 2: 227-231.
Pirasteh-Anosheh, H. and Emam, Y. (2012). Yield and yield components responses of bread and wheat to PGRs under stress conditions in field and greenhouse. Environmental Stress in Crop Science. 5: 1-18.
Radmehr, M., Lotfali-Ayeneh, A. and Mamaghni, R. (2005). A study of the reaction of middle, long and short season wheat genotypes to different sowing dates. Seed and Plant. 21(2): 175-189.
Rajala, A. 2004. Plant growth regulators to manipulate oat stands. Agriculture and food Science in Finland. 13:186-197.
Seyed Sharifi1, R. and Namvar, A. (2016). Plant density and intra-row spacing effects on phenology, dry matter accumulation and leaf area index of maize in second cropping. Biologija. 62(1): 46-57.
Sharif, S., Saffari, M. and Emam, Y. (2007). The effect of drought stress and cycocel on barley yield (Cv. Valfajr). Journal of Water and Soil Science (Science and Technology of Agriculture and Natural Resources). 10 (4) :281-291. (In Persian with English abstract).
Shekoofa, A. and Emam, Y. (2008). Effects of nitrogen fertilization and plant growth regulators (PGRs) on yield of wheat (Triticum aestivum L.) cv. Shiraz. Agricultural Science and Technology. 10, 101-108.
Sivritepe, N., Sivritepe, H.O. and Turkben, C. (2008). Determination of moisture content in grape seeds. Seed Science and Technology. 36: 198-200.
Subedi, K.D., Ma, B.L. and Xue, A.G. (2007). Planting date and nitrogen effects on grain yield and protein content of spring wheat. Crop Science. 47:36-44.
Taghizadeh, R. and Seyed Sharifi, R. (2011). Effect of nitrogen fertilizer on yield attributes and nitrogen use efficiency in corn cultivars. Journal of Water and Soil Science. 15(57): 209-217. (In Persian with English abstract).
Varvel, G.E., Schepers, J.S., and Francis, D.D. (1997). Ability for in season correction of nitrogen deficiency in corn using chlorophyll meters. Soil Science Journal. 61: 1233-1239.
Verma, K.K., Singh, M., Gupta, R.K. and Verma, C.L. (2014). Photosynthetic gas exchange, chlorophyll fluorescence, antioxidant enzymes and growth responses of Jatropha curcas during soil flooding. Turkish Journal of Botany. 38: 130-40.
Voltas, J., Romagosa, I. and Araus, J. L. (1997). Grain size and nitrogen accumulation in sink-reduction barley under Mediterranean conditions. Field Crops Research. 52: 117-126.
Wang, H., Li, Q., Liu, H.S. and Xiao, L.T. (2009). Chlorocholine chloride application effects on photosynthetic capacity and photoassimilates partitioning in potato (Solanum tuberosum L.). Scientia Horticulturae. 119: 113-116.
Yusefzadeh, M. Daneshvar, M. Shahrvasvand, S. and Sorkhe, H. (2013). The effects of ethephon and nitrogen fertilizer on yield and yield components of sweet sorghum. Scientific Journal Database. 44(2): 199-207. (In Persian with English abstract).