Impact of different tillage systems and fertilization on soil microbial community in canola production

Experiment was carried in a split plot based on randomized complete block design with three replications in two years. Main plots were consisted of conventional tillage (CT), minimum tillage (MT) and no tillage (NT). Six methods of fertilization including (N1): farmyard manure; (N2): compost; (N3): chemical fertilizers; (N4): farmyard manure + compost; (N5): farmyard manure + compost + chemical fertilizers and (N6): control were arranged in sub plots. Results showed that the highest soil bacteria number was obtained in N4 (194.4 × 106) and NT (135.4 × 106) treatments. The activities of urease (49.6 µg urea g-1 h-1), catalase (73.6 µg o2 g-1 h-1) and cellulase (17.8 µg glucose g1 h-1) were generally higher in the N2 and N4 treatments. The activity of acid and alkaline phosphatase and urease tended to be higher in the NT treatment compared to the MT and CT treatments. The maximum amount of grain yield was obtained from MT and N5 treatments.