Two field experiments were conducted to study the effect of some biofertilizers
with and without normal fertilization on sugar beet yield and the incidence of
cercospora leaf spots disease. The experiments carried out at The Experimental Farm of Tag AI-Ezz Research
Station in clay loamy soil during 2003/2004 and 2004/2005 using two of biofertilizers
containing N-fixing bacteria (Le., Rhizobacterin and Nitrobien), one containing P-
dissolving bacteria (Phosphorine) and the fourth is Microbien contains both of the two
types of bacteria. The obtained results revealed that the lasted biofertilizers could compensate
the plant v/ith more than half the recommended doses of the mineral nitrogenous and
phosphorus fertilizers.