Effect of Regulated Deficit Irrigation and Potassium Fertilizer on Root Dynamics, Yield and Its Components in Different Cultivars of Forage Sorghum

Document Type : Research Paper

Authors

Abstract

To study the effects of irrigation water (50%, 75%, and 100% of plant water requirement) and potassium fertilizer (0, 50%, and 100% required potassium fertilizer based on soil test) on the dynamics of root, yield, and shoots of sorghum varieties (Pegah, Karaj, and Speedfeed), a research was conducted in the Agricultural Research Center of Semnan province (Shahrood) in 2014. This research was conducted in pots and in field experiment. The experimental variables were irrigation water, potassium fertilizer, and varieties of forage sorghum. The treatments were arranged as split plots based on a randomized complete block design with three replications. In the pot experiment, 243 plastic pots with diameter of 30 and height of 60 cm were used. Irrigation water was calculated with Penman-Monteith method. Drip irrigation was used as irrigation system. Sampling was carried out from the roots in three phases during the season. The root volume was determined by immersion in water method. Shoots parameters such as leaf area, leaf dry weight, stem dry weight, and shoot weight were measured. The results showed that the effects of irrigation water, potassium fertilizer, and sorghum varieties were significant on the forage yield, root volume,  and dry weight of roots and shoots of the plants. The highest yield was obtained from the W100K100 treatment (102.8 ton/ha). Pegha variety showed the maximum yield. The maximum water use efficiency was obtained from the W75K100 treatment (20.5 kg/m3/ha). The W75K100Vp < /sub> treatment was introduced as a superior treatment. Potassium fertilizer could compensate the loss of yield. The mathematical equations expressing root volume and dry weight with time were determined during the season. The relationships between some parameters of the shoots and roots were determined.

Keywords


  1. پورعزیزی، م. فلاح، س. 1389. تأثیر کودهای آلی و شیمیایی بر خصوصیات کیفی علوفه سورگوم. همایش ملی دستاوردهای نوین در زراعت. شهریور . کرج. ایران.
  2. حبیبی، م. عبدی، م. و مهدی مهرپویان. 1392. مطالعه خصوصیات کیفی علوفه در دو رقم سورگوم علوفه­ای اسپیدفید و پگاه تحت شرایط کم آبی. دومین همایش ملی مباحث کشاورزی نوین. 28 آذر. ساوه.
  3. شیرمحمدی علی اکبر خانی، ز. 1392. ارزیابی بر هم کنش شوری و کم­آبیاری تنظیم شده بر  عملکرد و اجزای عملکرد ذرت علوفه ای و تعیین تابع تولیدآب – شوری. رساله­ی دوره­ی دکتری دانشگاه فردوسی مشهد.
  4. طباطبایی، س. ع. آناقلی، ا. 1389. ارزیابی مقاومت به شوری لاین­های داخلی سورگوم علوفه­ای در شرایط آزمایشگاه و مزرعه. گزارش پژوهشی سازمان تحقیقات و آموزش کشاورزی.
  5. علیزاده، ا . 1384.  اصول طراحی سیستم­های آبیاری. انتشارات دانشگاه امام رضا (ع ). 452 ص.
  6. معـاونی، پ. حیدری، ی.١٣٨3. تأثیر تراکم کاشت و دور آبیاری بر عملکرد و برخی صفات فیزیولوژیکی در سورگوم علوفه­ای. مجله علوم زراعی ایران. جلد 6 ، شماره 4 ، ص 382-374.
  7. م. ج. . ۱۳۷۸. بررسی وضعیت تعادل عناصر غذایی در خاک‌های ایران. مجله آب، خاک و ماشین، جلد ۱۰، ص 17-12.
  8. Berenguer, M.J., and J.M. Faci. 2001. Sorghum (Sorghum Bicolor L. Moench) yield compensation processes under different plant densities and variable water supply. European Journal of Agronomy 15:43–55.
  9. English, M., and S.N. Raja. 1996. Perspectives on deficit irrigation. Journal of Agricultural Water Management. 32:1–14.
  10. Ellis, F. B., and B. T. Barnes. 1980. Growth and development of root system of winter cereals grown after different tillage methods including direct drilling. Plant Soil 55:283-288.
  11. F.A.O. 2002. Deficit irrigation practices. Water Report No. 22. Koriem, S.O., El-Koleiy, M.M.A., Wahba, M.F. 1994. Onion bulb production from sets as affect by soil moisture stress. Journal of Agricultural Science. 25:185–193.
  12. Farooqi, A. A., and Kh. Bssreeramu. 2004. Cultivation of spice crops. Universities Press. pp:128-148.
  13. Fry, J., and B. Huang. 2004. Applied Turf grass Science and Physiology. John Wiley and sons pob, Inc., Hoboken, New jersey, Canada. 320p.
  14. Innes, P., and W. Black. 2001. The effect of drought on water use and yield of two sorghum genotypes. J. Agri. Sci. 96:603-610.
  15. Laboski, C. A. M., Dowdy, R. H., and J. A. Lamb. 1998. Soil strength and water content influences on corn root distribution in a sandy soil. Journal of Plant and Soil 203: 239-247.
  16. Liu, F., Andersen, M.N., Jacobsen, SE. and CR. Jensen. 2006. Effects of deficit irrigation (DI) and partial root drying (PRD) on gas exchange, biomass partitioning, and water use efficiency in potato. Journal of Horticulture Science. 109(2):113-117.
  17. Muller, B., Pantin, F., Génard, M., Turc, O., Freixes, S., Piques, M., and Y. Gibon. 2011. Water deficits uncouple growth from photosynthesis, increase C content, and modify the relationships between C and growth in sink organs. Journal of Experimental Botany. 62:15-29.
  18. Nickel, S. E., Kent Crookston , R. and M. P. Russelle. 1995. Root growth and distribution are affected by corn soybean cropping sequence. Agron. J. 87: 895-902.
  19. Sepaskhah, A., Zand Parsa, Sh., Ghasemi M. M., and B. Ghahraman .2006.comparison of two methods for deficit irrigation of sorghum. Iran-Water Resources Research. 2(2): 1-9.
  20. Sher, A., Lorenzo Barbanti, L., Ansar, M., and M. Malik. 2013. Growth response and plant water status in forage sorghum [Sorghum bicolor (L.) Moench] cultivars subjected to decreasing levels of soil moisture. Australian Journal of Crop Science. 7(6):801-808.