E Davaran hag - Department of agriculture, university of Tabriz
R Alizadeh - Department of agriculture, university of Karaj
F Rahimzadeh khoeii

This research was carried out to study the effect of Azospirillum on declining the consumption of nitrogen fertilizer on maize plant, var.Karaj.Single.Cross.704, at the Research Station of the Faculty of Agriculture in Tabriz University, in 2005.The treatments were consisted of different amounts of nitrogen fertilizer with four levels (0, 70, 140 and 210 kg N/ha) and with or without inoculation of seeds with the bacteria. The experiment was conducted at factorial bases with three replication in randomized complete block design .The results revealed that in the case of inoculation with bacteria, the highest yield of grain was produced(12.14 ton/ha) and in the case of with out inoculation the lowest yield of grain (10.68 ton/ha) was gained. The results showed that the inoculation with the bacteria increases the yield, the percentage of nitrogen in vegetative organs (shoots), the number of grain in a row, leaf area under falgleafs, ear length and the number of grain in ear. Also it was revealed that using 140 kg of nitrogen fertilizer in hectare and the inoculation with the bacteria increases the yield of the grains up to 30 percent(14.54 ton/ha).It can be concluded that, using 140 kg of nitrogen fertilizer in hectare and inoculation with Azospirillum could decline the application of nitrogen fertilizer up to 30%.The Azospirillum can be more effective and useful if we don’t use the nitrogen fertilizer

maize,nitrogen fertilizer,bacteria,azospirillum,fixing,biofertilizer