Gholamreza Hashemi - Department of Agronomy and Plant Breeding, Islamic Azad University, Boroujerd Branch,Boroujerd, Iran
Amin Farnia - Department of Agronomy and Plant Breeding, Islamic Azad University, Boroujerd Branch,Boroujerd, Iran
Mehrdad Rahnamaeian - Lorestan natural resources and agriculture reaserch center, Boroujerd agricultural reaserch station, Boroujerd, Iran
Morad Shaban - Young researchers and elite club, Boroujed branch, Islamic Azad University, Boroujerd, Iran

Objective: A field experiment was conducted at Dorud region, Iran, during 2013. The aim of this research was study on effect of different biofertilizers and irrigation closed time on some agronomic characteristics of sugar beet (Beta vulgaris L.). Methods: The experimental design was factorial based on RCBD with three replications. Treatments were three irrigation closed time [Oct-6 (A1), Oct-13 (A2) and Oct -21 (A3)] and threenitrogen biofrtilizers [Nitroksin (B1), Nitrokara (B2), Biozar (B3) and control (B4)]. Aftertreatments 3m2 in each plot harvested for leaf and root yield measurement. K%, Na%and N% were determined by Betalizer machine in Isfahan sugar beet factory. Results: Results showed that, the effect of all treatments on root yield was significant but all treatments were not significant on fresh leaf yield. Effect of different biofertilizers were significant on K% and N% and other treatment were not significant on them. The effectof any treatment was not significant on Na%. Among the nitrogen biofertilizers, Nitroksin and Biozar treatments has the highest K% and Nitrokara treatment has the lowest K% and Nitroksin treatment has the highest N% and Nitrokara treatment has the lowest N% and the differences of them were significant. In final we reviled that application of different biofertilizers and different irrigation closed time reviled that among the all treatment highest root yield was belonged at application of Biozar in Oct-13 irrigation closed time and minimum root yield was belonged at application of Nitrokara in Oct-21 irrigation closed time

Biofertilizer ، Root yield ، Sugar Beet ، Water