Effect of biofertilizer and nitrogen on nitrogen use efficiency and harvest index of two winter wheat (Triticum aestivum L.) cultivars

In order to study effects of biofertilizer and nitrogen on nitrogen use efficiency and harvest index of wheat (Triticum aestivum L.) an experiment was conducted with nitrogen rate (0, 33, 67, 100 kg/ha urea), seed biofertilization with nitragin and wheat cultivars (Alvand and MV17). Results showed that with increasing of urea application fertile tillers number per plant improved. When biofertilized seeds were planted, grain yield increased from 6017 kg/ha in control to 6591 kg/ha in application of 33 kg/ha urea and 6954 kg/ha in 67 kg/ha urea in Alvand, and from 3547 kg/ha in control to 4428 kg/ha in application of 33 kg/ha urea and 4724 kg/ha in 67 kg/ha urea in MV17. Seed biofertilization with nitragin increased harvest index of crop up to 2.3%. In biofertilized treatments, when wheat plants were fertilized with lower dose of urea, grain yield improved in both cultivars. With increasing of urea rate from 67 to 100 kg/ha the yield reduced. In non-biofertilized plants grain yield in those plots fertilized with full dose of urea was the highest. In experiment environmental condition with wheat seed biofertilization before planting we can improve grain yield and reduce urea application up to 33% of recommended dose.