Evaluation of defoliation on leaf water relations, chlorophyll content, and grain yield of triticale (x triticosecale wittmack) genotypes under water stress

Document Type: Full Article


1 College of Agriculture and Natural Resources of Darab, Shiraz University, I. R. Iran

2 Department of Crop Production and Plant Breeding, College of Agriculture, Shiraz University, Shiraz, I. R.Iran


Optimizing the source size and its utilization by the sink is one of the main factors enhancing the yield potential and decreasing water demand in crops when exposed to drought. To investigate the effect of defoliation on leaf water relations, chlorophyll content and yield components of five triticale genotypes including Sanabad, Juanillo, ET-83-3, ET-84-5 and ET-84-8 under well-watered (100% FC) and water stress (50% FC) conditions, a controlled experiment was carried out at Shiraz University in 2013. The results showed that ET-84-8 and Sanabad genotypes had higher chlorophyll content (ranged from 49.1 to 54.6 SPAD unit) under water stress. Among the triticale cultivars, water stress caused 21 to 42% decline in rate of water loss (RWL) In all genotypes except ET-83-3 and Juanillo, the excised leaf water retention (ELWR) was slowly decreased under water stress conditions. In all triticale genotypes except ET-84-8, water stress declined main shoot yield 21-22%, while in ET-84-8 was only 9%. Interestingly, in ET-84-8, grain number per spike was not affected by moisture regimes. Sanabad cultivar, with 2.57 g/g had the highest initial water content (IWC) at defoliation of all leaves except the flag leaf and penultimate leaf treatment under water stress. Under defoliation and water stress, ET-84-8 and Sanabad genotypes showed a greater 100-grain weight ranged from 3.60 to 3.74 g. It was concluded that triticale cultivars were more sink-limited especially under water stress, and source restriction by defoliation which had less effects on main shoot yield could be used as a useful tool for lowering water consumption during grain filling.


Main Subjects

Article Title [Persian]

ارزیابی روابط آبی برگ، محتوای کلروفیل و عملکرد دانه ژنوتیپ های تریتیکاله در شرایط کمآبی و برگزدایی

Authors [Persian]

  • احسان بیژن زاده 1
  • یحیی امام 2
1 دانشکده کشاورزی و منابع طبیعی داراب، دانشگاه شیراز، داراب ، ج. ا. ایران
2 گروه زراعت و اصلاح نباتات، دانشکده کشاورزی، دانشگاه شیراز، شیراز، ج. ا. ایران.
Abstract [Persian]

بهینه کردن اندازه مبدا و استفاده مواد پروده آن در مقصد یکی از عوامل مهم در افزایش پتانسیل عملکرد و کاهش تقاضای آب در گیاهان زراعی در شرایط تنش خشکی می باشد. بمنظور بررسی اثرات برگ زدایی بر روابط آبی برگ پنج ژنوتیپ تریتیکاله شامل سناباد، جوانیلو، 3-83ET- ،5-84ET- و 8-84ET- در شرایط آبیاری مطلوب (100 درصد ظرفیت مزرعه) و تنش کم آبی (50 درصد ظرفیت مزرعه)، آزمایشی گلخانه ای در سال 1392 در دانشگاه شیراز به اجرا در آمد. نتایج نشان داد که رقم 8-84ET- و سناباد محتوی کلروفیل بالاتری (در دامنه از 1/49 تا 6/54 واحد اسپد) در شرایط تنش کم آبی داشتند. در بین ارقام تریتیکاله تنش کم آبی باعث کاهش 21 تا 42 درصدی در سرعت از دست دادن آب برگ (RWL) شد. در همه ارقام به غیر از 3-83ET- و جوانیلو مقدار آب نگهداری شده در برگ (ELWR) به آرامی در شرایط تنش کم آبی کاهش یافت. در همه ارقام تریتیکاله به غیر از 8-84ET، تنش کم آبی عملکرد ساقه اصلی را بین 21 تا 22% کاهش داد در حالی که این کاهش در رقم 8-84ET-  تنها 9%  بود. جالب اینکه تعداد دانه در سنبله در رقم 8-84 ET- تحت تاثیر رژیم رطوبتی قرار نگرفت. همچنین وقتی همه برگ ها به غیر از برگ پرچم و برگ ماقبل پرچم حذف شدند، رقم سناباد با 57/2 گرم بر گرم دارای مقدار آب اولیه برگ (IWC) زیادتری بود. در شرایط تنش کم آبی و برگ زدایی، ارقام 8-84ET- و سناباد وزن هزار دانه بیشتری (در دامنه ای از 6/3 تا 74/3 گرم) داشتند. می توان نتیجه گرفت که ارقام تریتیکاله بویژه در شرایط کم آبی مقصد- محدود بوده و اعمال محدودیت مبدا از راه برگزدایی تاثیر کمتری در عملکرد دانه داشت، که این موضوع می تواند به عنوان ابزاری سودمند در کاهش آب مصرفی در دوره پر شدن دانه مورد استفاده قرار گیرد.

Keywords [Persian]

  • واژگان کلیدی: مقدار کلروفیل
  • مقدار آب اولیه برگ
  • سرعت از دست دادن آب برگ
  • اندازه مبدا
Ahmadi, A., & Joudi, M. )2007(. Effects of timing and defoliation intensity on growth, yield, and gas exchange rate of wheat grown under well-watered and drought conditions. Pakistan Journal of Biological science, 10, 379-380.
Alam, M.S., Rahman, A.H., Nesa, M.N., Khan, S.K., & Siddiquie, N.A. (2008). Effect of source and/or sink restriction on the grain yield in wheat. Journal of Applied Science Research, 4, 258- 261.
Ammar, K.,M., Mergoum, & S., Rajaram., (2004). The history and evolution of triticale. Pp. 1-9. In M., Mergoum, & H. Gomez-Macpherson (1sted). Triticale Improvement and Production. (pp.1-9). Rome, Italy.
Barraclough, P.B., & Kyte, J. (2001). Effect of water stress on chlorophyll meter readings in winter wheat. In W.J., Horst, M.K., Schenk, A., Burkert, N., Claassen&Flessa, H. (Ed.). Plant Nutrition- Food Security and Sustainability of Agro-Ecosystems, (pp. 722-766), Kluwer Academic Publishers, Netherlands.
Beadle, C.L., Ludlow, M.M., & Honeysett, J.L. (1993). Photosynthesis and production in a changing environment. Chapman and Hall, London. Pp. 113-128.
Bijanzadeh, E., & Emam, Y. (2010). Effect of defoliation and drought stress on yield components and chlorophyll content of wheat. Pakistan Journal of Biological Science, 13, 699-705.
Bijanzadeh, E., & Emam, Y. (2011). Evaluation of assimilate remobilization and yield of wheat cultivars under different irrigation regimes in arid climate.  Archives of Agronomy and Soil Science, 58, 1243-1259.
Borras, L., Slafer, G.A., & Otegui, M.E. (2004). Seed dry weight response to source–sink manipulations in wheat, maize and soybean: A quantitative reappraisal. Field Crops Research, 86, 131–146.
Dreccer, M.F., Grashoff, C., & Rabbinge, R. (1997). Source-sink ratio in barley (Hordeumvulgare L.) during grain filling: effect on senescence and grain protein concentration. Field Crops Research, 49, 269-277.
Emam, Y, & Seghatoleslami, M.J. (2005). Crop yield, physiology and processes. Shiraz University Press. 593 pp.(In Persian)
Emam, Y. ,& Dastfal, M. (1997). Above and below ground responses of winter barley plants to chlormequat in moist and drying soil. Crop Research, 14, 457-470.
Fayaz N., & Arzani A., 2011. Moisture stress tolerance in reproductive growth stages in triticale (X Triticosecale Wittmack) cultivars under field conditionsCrop Breeding Jornal, 1, 24-34. (In Persian)
Giunta, F.R. Motzo, & Deidda. M. (1993). Effect of drought on yield and yield components of durum-wheat and triticale in a Mediterranean environment. Field Crops Research, 33, 399-409.
GolestaniAraghi, S., & Assad, M.T. (1998). Evaluation of four screening techniques for drought resistance and their relationship to yield reduction ratio in wheat. Euphytica, 103,293–299.
Guttieri, M.J., Stark, J.C. Brien, K.O., & E. Souza, (2001). Relative sensitivity of spring wheat grain yield and quality parameters to moisture deficit. Crop Science, 41, 327-335.
Haley, S.D., Quick, J.S., & Morgan, J. A. (2002). Excised-leaf water status evaluation and associations in field-grown winter wheat. Canadian Journal of Plant Science, 83, 55-63.
Jaradat, A., & Konzak, C.F. (2003). Screening of wheat genotypes for drought tolerance. I. Excised-leaf water retention. Cereals Research Communication, 31, 179-187.
Joudi, M.,  Ahmadi, A., Poustini, K., & Sharifzadeh, F. (2006).  Effect of leaf elimination on the effectiveness of flag leaf photosynthesis and seed growth in bread wheat. Iranian Journal of Agriculture Science, 2, 203-211.
Lelley, T. (2006). Triticale: A low-input cereal with untapped potential. In: Singh, R.J., & Jauhar, P. P. (Eds.) Genetic resources chromosome engineering and crop improvement. (pp. 395–430). Boca Raton, CRC Press, Taylor & Francis Group, FL.
Lonbani M., & Arzani A. (2011). Morpho-physiological traits associated with terminal drought stress tolerance in triticale and wheat . Agriculture Research, 9, 315–329.
Matin, M.A., Jarvis, H.B., & Hayden, F. (1999). Leaf water potential, relative water content and diffusive resistant as screening techniques for drought tolerance in barley. Agronomy Journal, 91,100–105.
Oettler, G. (2005). Centenary review. The fortune of a botanical curiosity-triticale: Past, Present and future. Journal of  Agriculture Science, 143, 329-346.
Pfeiffer, W.H. (2003). Triticale improvement strategies at CIMMYT: Exploiting adaptive patterns and end-use orientation. Triticale Topics, 21, 18-27.
Riaz, R., & Choudhry, M.A. (2003). Genetic Analysis of some economic traits of wheat under drought condition. Asian Journal of Plant Science, 2, 790-796.
Savin, R., & Slafer, G.A. (1994). Shading effects on the yield of an Argentina wheat cultivar. Journal of Agriculture Science, 116,1–7.
Schnyder, H. (1993). The role of carbohydrate storage and redistribution in the source-sink relations of wheat and barley during grain filling.New Phytologica, 123, 233–245.
Schonfeld, M. A., Johnson, R.C., Carver B.F., & Mornhinweg, D.W. (1998). Water relations in winter wheat as drought resistance indicators. Crop Science, 28, 526–531.
Wang, H., & Clarke, M. (1992). Relationship of excised-leaf water loss and stomatal frequency in wheat. Canadian Journal of Plant Science, 73, 93-99.
Wenzel, W.G. (1997). Leaf water retention of excised leaves as a measure of drought resistance in grain sorghum (Sorghum bicolor L.) genotypes. South African Journal of Plant Science, 14:31-34.
Yang, R.C., Jana, S., & Clark J.M. (1991). Phenotypic diversity and associations of some potentially drought-responsive characters in durum wheat. Crop Science, 31, 1484–1491.
Zadoks, J.C., Chang, T.T,, & Konzak, C.F. (1974). A decimal code for the growth stages of cereals. Weed Research, 14:11–16.
Zhenlin, W., Yanping, Y., Mingrong, H., & Hongmingand, C. (1998). Source-sink manipulation effect on post anthesis and grain setting on spike in winter wheat. Photosynthetica, 35, 453-459.