BACKGROUND: Fertilizer management plays an important role for obtaining satisfactory yields and to increase crop productivity. Nutrient management may be achieved by the involvement of organic sources, bio fertilizers, and micro-nutrients. Studies have shown that long-term use of fertilizers reduces crop yields. This decrease is due to the acidification of the soil, the reduction of biological activity of the soil and the inappropriate physical properties of the soil.OBJECTIVES: The present study was conducted to evaluate the effect of different level of growth stage of use seaweed extract and combination of seaweed extract and Urea fertilizer on plant height, leaf area index, biologic yield and nitrogen use efficiency under warm and climate condition in Khuzestan province (Southwest of Iran).METHODS: Current research was arranged via factorial experiment based on the randomized complete block design with three replications. The treatments included growth stage of use seaweed extract (G1: 100% at tillering stage, G2: 50% at tillering stage+50% at booting stage, G3: 50% at tillering+25% at booting +25% at beginning at Pollination) and different combination of seaweed extract and Urea fertilizer (S0/N100= Nonuse of seaweed extract + 100% Urea fertilizer, S1.5/N66= 1.5 L.ha-1 seaweed extract + 66% Urea fertilizer, S3/N33= 3 L.ha-1 seaweed extract + 33% Urea fertilizer, S4.5/N0= 4.5 L.ha-1 seaweed extract + Nonuse of Urea fertilizer).RESULT: According result of analysis of variance effect of growth stage of use seaweed extract and different combination of seaweed extract and Urea fertilizer on all measured traits was significant but interaction effect of treatments was not significant. Mean comparison result the maximum biologic yield was noted for apply seaweed extract at 50% at tillering stage+50% at booting stage and S1.5/N66 treatment. The highest amount of nitrogen use efficiency belonged to S3/N33.CONCLUSION: Finally use 1.5 L.ha-1 seaweed extract + 66% Urea fertilizer along 50% at tillering +50% at booting stage by improve biologic yield can advised for producers. پرونده مقاله