Evaluation of Some Soil Quality Indices as Influenced by the Intercropping Patterns of Bean and Moldavian Balms, and Microbial Inoculation

Intercropping under microbial inoculation has been suggested as a method to improve the soil quality indices. The objective of this study was to evaluate the effect of microbial inoculation on some soil quality indices of moldavian balms-and bean-planted soils in sole cropping and intercropping. This experiment was carried out in the form of a factorial based on a randomized complete block design with three replications in greenhouse condition. Studied factors were microbial inoculation (AMF, PGPR, AMF+PGPR and without microbial inoculation) and planting patterns (sole cropping of moldavian balms and bean, 1 row moldavian balms + 1 row bean (1:1), 2 row moldavian balms + 2 row bean (2:2), 2 row moldavian balms + 1 row bean (2:1) and 1 row moldavian balms + 2 row bean (1:2)). At the end of the growth period, microbial respiration (BR), substrate-induced respiration (SIR), microbial biomass carbon (MBC), metabolic quotient ( q CO 2 ) and carbon availability index (CAI) in moldavian balms-and bean-planted soils were determined. The results showed that the intercropping patterns and microbial inoculation had a significant effect on all soil quality indices, in moldavian balms and bean plantation. The BR and SIR in the 2:1 intercropping moldavian balm under PGPR+AMF inoculation were measured to be 1.21 and 1.17 times higher than those of sole cropping, respectively. The 2:1 intercropping with PGPR+AMF inoculation increased MBC by 1.11 and 1.24 times, as compared to sole cropping of bean-and moldavian balm-planted soils, respectively. Different intercropping patterns and microbial inoculation increased soil CAI and decreased q CO 2 . In general, the application of intercropping and the potential use of microorganisms could improve the soil quality indices.