In order to evaluate the effect of biofertilizers (nitroxin and phosphate barvar2), vermicompost and chemical fertilizers
on the quantity and quality traits of sugar beet (Beta vulgaris L.), an experiment was conducted in randomized complete
block design (RCBD) with 13 treatments and three replications at Agricultural and Natural Resources Research Station
of Miandoab, Iran in 2015. The treatments were 100% chemical fertilizer (350, 100 and 50 kg ha-1 urea, superphosphate
triple and potassium solphate) as control (T1), 10 t ha-1 vermicompost (T2), 20 t ha-1 vermicompost (T3), 10 t ha-1
vermicompost + 50% chemical fertilizer (T4), 20 t ha-1 vermicompost + 50% chemical fertilizer (T5), nitroxin +
phosphate barvar 2 (T6), 10 t ha-1 vermicompost + nitroxin + phosphate barvar2 (T7), 20 t ha-1 vermicompost + nitroxin
+ phosphate barvar2 (T8), nitroxin + phosphate barvar2+ 50% chemical fertilizer (T9), 10 t ha-1 vermicompost +
chemical fertilizer (196 and 85 kg ha-1 urea and superphosphate triple) (T10), 20 t ha-1 vermicompost + chemical
fertilizer (40 and 70 kg ha-1 urea and superphosphate triple) (T11), nitroxin + phosphate barvar 2 + 10 t ha-1
vermicompost + 50% chemical fertilizer (T12) and nitroxin + phosphate barvar2 + 20 t ha-1 vermicompost + 50%
chemical fertilizer (T13). The highest (47.8) and lowest (39.2) chlorophyll indices were obtained in T13 and T2
treatments, respectively. Also, the highest root yield (66366 kg ha-1) was achieved in T13 treatment that was not
significantly different from T12 and T11. Due to a combination of organic and biological amendments with chemical
fertilizers, sugar yield was increased significantly in T13 treatment due to increases in root yield and sugar content. The
sugar yield and white sugar yield in T13 treatment increased 16.7% and 23.5%, respectively compared with T1.
Generally, based on root yield, white sugar yield and extraction coefficient of sugar, integrated application of nitroxin +
phosphate barvar2 + 20 t ha-1 vermic