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Soil microorganisms, especially rhizobacteria, play a key role in soil phosphorus (P) dynamics and the subsequent availability of phosphate to plants. Utilization of phosphate-solubilizing bacteria as biofertilizers instead of synthetic chemicals is known to improve plant growth through the supply of plant nutrients, and may help to sustain environmental health and soil productivity. The main purpose of this study was to identify new phosphate-solubilizing bacteria isolated from runner bean rhizosphere. Ten out of 25 isolated bacterial strains solubilized Ca3(PO4)2 in qualitative and quantitative P-solubilization. The strain that exhibited the highest potential to solubilize Ca3(PO4)2, was selected for further determination of the mechanisms involved in the process. The medium pH was measured, organic acids released in the culture medium were identified by HPLC analysis, and the acid and alkaline phosphatase activities were determined. Our results showed that strain R7 solubilized phosphorous through the production of various organic acids such as lactic, isocitric, tartaric and pyruvic acids, and that it can be used as a potential biofertilizer.

The adsorption potential of alkaline treated straw (wheat and corn) in mixture with soil, has been investigated for the removal of sulfonylurea molecules from an aqueous solutions. The surface characteristics were investigated by scanning electron microscopy and Fourier Transform Infrared - FTIR, while the adsorbent capacity was evaluated using batch sorption tests and liquid chromatography coupled with mass spectrometry. Surface analysis of alkaline treated straw samples by scanning electron microscopy - SEM showed the increasing of the surface roughness improving their functional surface activity. An increase (337.22 mg g−1) of adsorption capacity of sulfonylurea molecules was obtained for all studied straw. The Langmuir isotherm model was the best model for the mathematical description of the adsorption process indicating the forming of a surface sorption monolayer with a finite number of identical sites. The kinetics of sulfonylurea herbicide followed the pseudo-second order mechanism corresponding to strong chemical interactions. The results sustained that the alkaline treated straw have biosorption characteristics, being suitable adsorbent materials.

Pedo-biological indicators, together with physical and chemical indicators, are important elements in the complex task of determining soil quality and reducing negative effects of soil degradation. In this chapter we present the results of the soil biology research on degraded lands by pluvial erosion, disposed in agroterraces, located in North–Eastern part of Romania. The experiment was established in a sloping field in Podu-Iloaiei, Iasy county on a Cambic Chernozem at 0–20 cm depth to study the seasonal evolution (spring-summer) of the biotic potential (soil respiration and cellulolysae) without irrigation. Our data deriving from this experiment indicate that disposed antierosional measures such as agroterraces, have produced lower values of the biological activity on top slope, in control section and, also, in various fertilized variants. Much better results of tenaces were recorded on lower slopes. The effects of pluvial erosion have a higher negative influence on soil biological activity. The excessively dry summer season had a stressing and restricting effect on biological activity of the soil as well. The Indicator of Vital Activities Potential (IVAP) was correlated with soil physical and chemical indicators to establish possible relationships.

The use of rhizobacteria as biofertilizers is one of the most promising biotechnologies to improve primary production with low inputs in fertilizers. In this context, the main goal of this study was to establish if the interaction between different rhizobacteria strains with Glycine max L. plants have a positive effect on the total soluble protein, carbohydrates and lipids content of soybeans. Our results revealed that there are no significant differences between the seeds produced by inoculated plants and those produced by the non-inoculated plants regarding soluble reducing carbohydrate content, lipid content and relative humidity. In the case of soluble protein content, rhizobacteria inoculated plants produce beans that contain a greater amount of soluble protein per gram. No qualitative differences could be shown, making our tested rhizobacteria strains an appealing strategy for improving soybean protein production.

Soil tillage systems have a major influence on soil physical characteristics. Optimal soil physical conditions for crop rooting are a result of complex interactions between soil structure and oxygen and water supply to plants roots. The experiment has been conducted in the Didactic Station of the University of Agricultural Sciences and Veterinary Medicine of Iasi, Ezareni Farm. The purpose of this experiment was to investigate the influence of three soil tillage systems (a reduced tillage system, a no-tillage system and conventional tillage system) on several physical characteristics of the soil, such as soil bulk density, soil porosity and soil structural stability.