Effects of amounts and nitrogen fertilizer splitting on yield, yield components and dry matter remobilization of wheat (cv. Chamran)

This experiment was conducted as factorial based on completely randomized blocks design with 3 replications during 2014-2015 in Ramhormoz, Khozestan province. The experiment consisted of two factors: nitrogen fertilizer rates: (zero, 50, 100 and 200 kg per hectare) and split nitrogen application included: T1 = (50% at planting + 50% at stem elongation), T2 = (33% at planting + 33% at stem elongation + 33% before ear emergence), T3 = (25% at planting + 50% + 25%at stem elongation before ear emergence) and T4 = (25% at planting + 25% + 25% at stem elongation before ear emergence + 25% in the milky stage. The results showed that difference between the levels of nitrogen fertilizer in plant height, number of spikes per square meter, grain number per spike, 1000-seed weight, grain yield, biological yield, harvest index and the amount and efficiency of current photosynthesis at 1% level of probability and remobilization rate of dry matter at 5% level of probability. Effect of split application of nitrogen on plant height, number of spikes per square meter, grain yield, biological yield and current photosynthesis at 1% level of probability and the efficiency photosynthesis current at 5% level of probability was significant. The interaction of the amount and nitrogen fertilizer splitting on biological yield and efficiency of dry matter remobilization and efficiency of current photosynthesis at 1% level of probability was significant. The highest grain yield was in N2 (100 kg ha nitrogen) with 5.5141 kg/ha and fertilizer splitting in T3 (25% at planting + 50% + 25% at stem elongation before ear emergence) 4.4592 kg/ha, respectively. The greatest amount and efficiency of current photosynthesis were observed in N2 (100 kg/ha nitrogen) and T3 (25% planting + 50% + 25% stem elongation before Ear emergence). In general, consuming 100 kg/ha of nitrogen fertilizer with T3 splitting (25% planting + 50% stem elongation + 25% before Ear emergence) increase yield and yield components compared to other treatments and it can be recommended in the region of study.