Abstract
Wheat (Triticum aestivum L.) was cultivated in pots of sandy soil and inoculated with Rhizobium (Rh), mycorrhizae (VAM) or both. The object was to verify the potential of these inocula on wheat production, nutrient acquisition and microbial biomass N (MBN) in relation to N and P fertilization. Nitrogen and phosphorus fertilizers were applied at rates of, 0 (N0P0); 25 mg kg(-1) soil N and 3.3 mg kg(-1) soil P (N1P1) and 50 mg kg(-1) soil N and 6.6 mg kg(-1) soil P (N2P2) in the form of ((NH4)-N-15)(2)SO4 and super-phosphate, respectively. The results revealed that the highest dry matter and N uptake by wheat shoot were obtained with the dual inoculation (Rh+VAM) at N2P2 rates of N and P fertilizers. Maximum grain yield was obtained with single inoculum of AM fungi while N and P uptake were with dual inoculation under N2P2 treatment. Inoculation with Rh either alone or in combination with AM had an enhancing effect on wheat growth and N and P uptake. Exception for soil treated with the lowest level of fertilizer, there was an increase in microbial biomass N following bio fertilization. The impact of bio and/or chemical fertilizers on soil microbial biomass-N now needs trials on a field scale.