This report is the result of research work in the field of "The Union" district of La Shilcayo between the months of June 2003 to February 2004 research. Aimed to evaluate the effects of four concentrations of Efficient Microorganisms EM (Efficient Microorganisms), in the town of homópteros (maggots and aphids) in orange (Citrus sinensis), in the valley on May in the region of San Martin, a goal that was achieved and whose approach was determined by the high incidence of pests in the citrus activity in the region, specifically the homopterous order. The research design used was the challenge of DBCA randomized complete block with four replicates per treatment. The treatments used were four, each treatment contenla a given concentration of EM effective microorganisms; for treatment 1 (T1) 0,50%, for treatment 2 (T2) 1,00%, for treatment 3 (T3) 1.50%, and for treatment 4 (T4) 2.00% additi...