Response of yield of maize to water stress and nitrogen In various stages of reproduction

n order to evaluate the effect of water restriction at different stages of reproductive andnitrogen levels, the corn factorial experiment in a randomized complete block designwith three replications was conducted in Tabriz University at the Agricultural ResearchStation. Operating systems were in four level (Irrigation after 70 mm evaporation ofClass A evaporation basin, irrigation stop at flowering stage, irrigation stop at grainfilling stage and irrigation stop at flowering and grain filling) and four level of nitrogen(control group or no nitrogen fertilizer, 100 kg/ha, 200 kg/ha and 300 kg/ha). Theresults showed that the effect of water stress and nitrogen was significant on all traits. Inaddition, their opposite effect in all traits other than the number of rows per ear wassignificant at the 1% level. So, with intensified water stress in a reproductive stage wasreduced significantly. On the other hand, the increase in irrigation has increased theamount of nitrogen in all studied parameters. Treatment of water restrictions in theflowering stage, grain filling stage, flowering and grain filling stages decreased by 22,41/6 and 64/13 percent grain trait. So, the most sensitive reproductive stage of corngrowth stages was identified the stage of flowering rather than water deficit.

Keywords:

corn , water restrictions , reproductive , nitrogen