Document Type : Original Article


1 MS in Agriculture, Islamic Azad University, Esfahan, Iran

2 Associate Prof, Faculty of Agriculture, Islamic Azad University, Esfahan, Iran

3 Ph.D. students in Agronomy, Faculty of Agriculture, University of Tabriz, Tabriz, Iran

4 MS in Agriculture, University of Razi, Kermanshah, Iran


The experimental was split plot in a randomized complete block design with three replications. In this experiment, different levels of nitrogen in the main plots included four levels (0, 50, 100 and 150 N) kg.ha-1 urea and wheat varieties, including cultivars, Sepahan and SW were placed in the subplots. Results showed that nitrogen fertilizer and cultivar were significant effects on maximum light absorption. Fertilizer treatment of 150 kg.ha-1 nitrogen resulted in maximum light absorption compare to other treatments. Maximum light absorption was related to Pishtaz cultivar. The interaction between nitrogen and cultivar on maximum light absorption was significant at 5% probability level. Treatment of 150 kg.ha-1 nitrogen with Pishtaz cultivar had the highest average of light absorption. As well as the calculated extinction coefficient of light during the growing season to control treatment, 50, 100 and 150 kg.ha-1 nitrogen was respectively equal to -0.4675,  -0.4794, -0.4858 and -0.495 and for Pishtaz, Sepahan and SW cultivars was -0.488, -0.4618 and -0.4504 respectively. Results indicate that in order to achievement to maximum light absorption, 150 kg.ha-1 nitrogen fertilizers together with Pishtaz cultivar at the condition similar to this study seems to be appropriate


Blue EN, Mason SC, Sander DH (1990). Influence of planting date, seeding rate and phosphorus rate on wheat yield. Agronomy Journal, 82: 162-168.
Cassman KG, Bryant DC (1992). Nitrogen supply effects on partitioning of dry matter and nitrogen to grain of irrigated wheat. Crop Sci. 32:2251-255.
Flent F, Kiniry JR, Board JE, Westgate ME, Reicosky DC (1996). Row spacing Effects on Light Extinction coefficients of corn, sorghum, soybean and sunflower, 88: 185-190.
Kiniry JR, Landivar J.A, Witt M, Gerik TJ, Cavero J, Wade LJ (1998). Radiation use efficiency response to vapor pressure deficit for maize and sorghum. Field Crops Res. 56, 265-270.
Kobata Tj, palta A, Saide MB (1992). Rate of development of post anthesis water deficit and grain filling of spring wheat. Crop Sci.32:1238-1242.
Kocheki A, Rashid Mohasel M, Nasiri M, Sadr Abadi R (1988). Physiological basis of crop growth and development. Mashhad: Razavi Cultural Foundation Press, 404 pages.
Major DJ, Otegu BW (1996). Leaf area light interception and development in maize radiation use efficiency. Agronomy Journal, 83: 895-903.
Qalambor MR, Fathi A, Seyadat A (1998). The efficiency of absorption of light (radiation) during the growth of soybean plants growing under N fertilizer and Planting. Iranian Congress of Agronomy Branch Karaj.
Robert B, Mesdag BD, Dingena A (2000). Bread-Making Quality of Wheat, Springer, p. 3, ISBN 0-7923- 6383-3.
Shahsavar N, Safari M (2005). The effects of N on yield components on three wheat cultivars yield. Pagohesh and Sazandegi J. 66: 124-140.
Sinclair TR, Horie T (1989). Leaf nitrogen, photosynthesis, and crop radiation use efficiency: A review. Crop Science. 29: 90-98.
Wang S, cowan IR, Farquheir GD (1985). Leaf conductance in relation to rate co2 assimilation: I. Influence of nitrogen nutrition photon flux density, and ambient partial pressure of co2 during ontogeny plant phi solo. 78: 821-825.