Two varieties of sweet pepper (Marconi and California wander ) inoculated with Azide resistant mutants induced in Azotobacter . Three Azotobacter strains used in this study were treated with three concentrations of sodium azide as follows, 25, 36 and 46 μg / ml. Most biofertilizer inoculants showed significant increase in growth parameters (root and shoot dry weight at 40 days plant-old , number of branches and plant height ) above uninoculated plants in field and pots experiments. Whereas, four inoculates (Azr1, Azr2, SMR230 and Azr5) induced significant increase in the number of branches per plant above the full dose in pots experiment. All biofertilizer inoculants (except for three inoculants; Azr1 , Azr2 and Azr3) appeared significant increased in root dry weight with CW variety above the full dose in field experiment. Whereas, only three inoculants (SMR230, Azr4 and Azr6) appeared the same trend with M Variety. The interaction between varieties and biofertilization revealed significant effect on root dry weight at 40 days plant-old on field experiments and number of branches in pots and field experiments. All Azotobacter strains and their mutants induced significant increase in yield components (number and weight of fruits per plant) above uninoculated plants in pots and field experiments. However, three inoculants (ATCC 132, SMR230 and Azr6) appeared significant increase in the number of fruits per plant above the full dose in the field experiment. Most of Azotobacter inoculants appeared significant increase above uninoculated plants in shoot biochemical traits (total Chlorophyll , nitrogen percentage at 40 days plant-old and nitrogen percentage at the end of season) among the plants grown in the field and pots. One inoculant ATcc132 appeared significant increase in total chlorophyll concentration with CW variety above the full dose in field experiment. Most inoculants appeared significant increase in nitrogen concentration at the end of season with M variety above the full dose in pots experiment whereas three inoculants (Atcc132, Azr3 and Azr5 ) appeared the same effect with CW variety above the full dose in pots experiment. The interaction between pepper varieties and biofertilizeras inoculants revealed significant effect on chlorophyll a concentration in pots experiment and in total chlorophyll in field , as well as, in nitrogen percentage at the end of season in pots and field experiments.