اثر مقادير مختلف آبياري تكميلي و نيتروژن بر عملكرد و اجزاي عملكرد گندم ديم رقم سبلان

Effects of Supplemental Irrigation and Nitrogen Rates on Yield and Yield Components of Rainfed Wheat Cultivar Sabalan

In order to investigate the effects of supplemental irrigation and nitrogen rates on yield and yield components of wheat, a field experiment was conducted as split plot arranged in a randomized complete block design (RCBD) with three replications, during 1999-2002 at Maragheh Agricultural Research Station of Dryland Agricultural Research Institute (DARI). The treatments included four levels of irrigation (rainfed, 1/3, 213 and 313 of full supplemental irrigation) as main plots and five N rates (0, 30, 60, 90 and 120 kgNha^-1) as sub plots. Grain, Straw and biological yield, harvest index, height, kernel number per spike (SIP) and 1000KW were determined from the middle of each plots. Yields of rainfed conditions varied with seasonal rainfall and its distribution, with all main factors had significant effects. With irrigation, crop response were generally significant up to 60 kgNha^-1 . Optimum level of supplemental irrigation was 113 of full supplemental irrigation with 60 kgNha had maximum water use efficiency (30kgmm^-1) and good yield. (minimum water use especial one time irrigation at planting time).