Two field trials were conducted at Sakha Agric. Res. Station during the two successive summer growing seasons of 2010 and 2011. Cowpea plants (vigna unquiculata (L.) walp.) variety Dokki 331, were inoculated with micro symbiont . Bradyrhizobium sp < /em> along with urea fertilizer at 40 and 80 kg N/fed . applied in two equal doses : at 30and 45 days after sowing . The investigation lasted for three months in the two seasons of study aiming to survey the occurring soil predacious mites, miscellaneousmiteand Collembola in four Nodulation and N- fertilization : Nodulated + 50%N,Nodulated+100%N, Non – Nodulated+50%N, and Non - Nodulated +100%N under field conditions and the diversity between species Nodulation and N- fertilization. Results revealed occurring of 8 species of predacious mite, belonging to 7 families in all Nodulators and N- fertilizers during the two seasons . while miscellaneous mite had 14 species belonging to 13 families in all Nodulators and N- fertilizers during two seasons . except for Non - Nodulation +100%N during seasons 2010, it had 13species belonging to 12 families. Also, 5 species of Collembolabelonging to 5 families in both two seasons. Results indicated that the population density of the soil mite and Collembola increased with application of both microbial inoculants and N-fertilization , recording the highest figure at 80kg N/fed . Amblyseius sp < /em> and Cheyletus malaccenis (oudmans) were the most dominant species under different application of microbial inoculants and N- fertilization .While , Cheyletus eruditus (oudmans )was the least species to be recorded .Pygmephorus sp < /em> was the dominant species under cowpea field in the two seasons under different types of Nodulators and N- fertilizers. While , Galumna sp < /em> was the least one proistoma sp < /em> was the dominant species in the two seasons under different types , of Nodulators and N- fertilizers , while , onychiurus sp , Hypogastura sp < /em> , Tulbergi sp < /em> and Entombyra sp < /em> were least recorded species .
Diversity index values of predacious mite species were (0.8456, 0.8638, 0.9330, 0.8525) and( 0.8753, 0.8874,0.8659, 0.8866). While miscellaneousmite, were (2.1411, 1.0919, 2.7336, 1.0888) and (1.1047,1.1169, 1.1047 , 1.1096 ) on the other hand Collembolawere(0.6974, 0.6966 , 0.6978, 0.6985) and (0.6977, 0.6976, 0.6981, 0.6984) for Nodulated + 50%N, Nodulated+100%N, Non – Nodulated+50%N, and Non - Nodulated +100%N during seasons (2010 and 2011) , respectively.