اثر اسید سالیسیلیک و پاکلوبوترازول بر کارآیی مصرف آب و عملکرد ذرت تحت تنش رطوبتی

Water is major restrictive factor influencing yield. In order to investigate the effect of antitranspiration substances and water stress on growth and yield of maize, an experiment was carried out in research farm of Bu-Ali Sina university of Hamedan in field season 2009. The experiment was a split plot in completely randomized block design with three replications. Three water regimes (7, 11, 15) as the main plot and antitranspiration substances (salicylic acid (SA) and paclobutrazol (PBZ)) as sub-plot. Interaction between SA and three water regimes significantly increased grain yield by 13.69, 17.24, 22.93 percentage compared to untreated plants, respectively. Using SA in three water regimes increased water use efficiency in terms of grain yield and dry matter compared to untreated plants. Spray of PBZ under three water regimes did not affect water use efficiency in terms of dry matter. Antitranspirant substances reduced evaporation and transpiration. More plant moisture storage increase dry matter production, grain yield and grain yield and dry matter production base-water use efficiency.