Iodine uptake and translocation was studied in cabbage and tomato cultivated on different soil types (sand, sandy silt, silt) by applying irrigation water containing iodine at concentrations of 0.1 and 0.5 mg/L. Iodine treatment at the concentrations applied did not significantly influence the photosynthetic efficiency and chlorophyll concentration of cabbage and tomato leaves. The growth of cabbage leaves cultivated on sand and sandy silt soil with iodine treatment was slightly stimulated, while, on silt soil, it remained unchanged; for tomato plant parts, independent of the soil-type, the dry mass values remained constant. It can be concluded that iodine treatment had no negative effect on the physiological characteristic of cabbage and tomato plants. Applying 0.5 mg/L in the irrigation water, the highest biofortification with iodine was achieved in plants cultivated in sandy soil and the iodine concentration calculated in the dry matter amounted to 10 and 3.6 mg/kg in the leaves and fruits of cabbage and tomato, respectively. Considering the iodine and moisture content of cabbage leaves and tomato fruits, the consumption of 100 g of fresh vegetable would cover about 80% and 15% of the recommended iodine intake, respectively. The presence of iodine resulted in a reduction in Fe and P concentrations in tomato fruits independent of the soil-type; however, the concentration of Mg, Cu, Mn, Zn, and B remained practically unchanged. However, for cabbage, no similar trend for Fe and P was observed.

The aim of this work was to study the colonization of indigenous arbuscular mycorrhizal fungi (AMF) species in fine-roots of poplar clones. Roots of 7 poplar clones were sampled from a 1-year-old trial established at an industrial site strongly polluted with heavy metals at Balatonfűzfő , Hungary. The poplar clones have shown variable degrees of colonization by AMF, suggesting differential host susceptibility or mycorrhizal dependency. After outplanting the percentage of poplar survival was strongly correlated with the frequency of AMF infection. Two clones that survived at the lowest ratio after outplanting had not been colonized by AMF in contrast to those which survived to a much higher extent.

The characterization of mycorrhizal status in hosts can be a good indicator of symbiotic associations in inoculation experiments or in ecological research. The most common microscopic-based observation methods, such as (i) the gridline intersect method, (ii) the magnified intersections method and (iii) the five-class system of Trouvelot were tested to find the most simple, easily executable, effective and objective ones and their appropriate parameters for characterization of mycorrhizal status. In a pot experiment, white clover (Trifolium repens L.) host plant was inoculated with 6 (BEG144; syn. Rhizophagus intradices) in pumice substrate to monitor the AMF colonization properties during host growth. Eleven (seven classical and four new) colonization parameters were estimated by three researchers in twelve sampling times during plant growth. Variations among methods, observers, parallels, or individual plants were determined and analysed to select the most appropriate parameters and sampling times for monitoring. The comparability of the parameters of the three methods was also tested. As a result of the experiment classical parameters were selected for hyphal colonization: colonization frequency in the first stage or colonization density in the later period, and arbuscular richness of roots. A new parameter was recommended to determine vesicule and spore content of colonized roots at later stages of symbiosis.

In the present study, changes in the infectivity and effectiveness of four Glomus mosseae strains of different origin were investigated in calcareous loamy chernozem soils treated with Cd at three levels (0, 50, 100 mg Cd kg ⁻¹ ) in a pot experiment. Frequency of infection (F%), arbuscular richness (a%) and shoot dry matter, macro-(N, P, K, S, Ca, Mg) and microelements (Zn, Cu, Ni, Mn, Mo, Co) and the Cd content of the host plants were compared to determine whether there was any variability in infectivity and effectiveness between G. mosseae strains of different origin. Functional diversity was found in the infectivity and effectiveness of the studied G. mosseae strains. In Cd-treated soil, AMF inoculation was beneficial to the plant growth, P uptake and shoot Cd content of the host. However, the higher uptake of other macro- and microelements was noted for non-mycorrhizal plants compared to mycorrhizal plants. The lower shoot content of some elements did not cause nutrient deficiency in mycorrhizal plants. The present results support the hypothesis that in polluted soils, the development of mycorrhizal symbiosis has the potential for AMF to protect their hosts against Cd toxicity rather than to improve nutrient uptake.

The effect of five rock phosphates with different solubility (from Algeria, North Florida, North Carolina, Senegal, and Morocco) and that of single superphosphate (SSP) alone or with lime was investigated on the root colonization of red clover with indigenous arbuscular mycorrhizal fungi (AMF). In a pot experiment, the phosphorus (P) sources were applied at four rates (0, 100, 400, and 1600 mg total P₂O₅ kg⁻¹ dry soil) to an acidic sandy soil (Nyírlugos) and to an acidic clay loam soil (Ragály). The arbuscule content of the roots was more sensitive to various rock phosphates than the infection frequency. No mycorrhizal colonization of roots was observed in the Nyírlugos soil at the 1600 mg P₂O₅ kg⁻¹ level of SSP or in either soil at the 1600 mg P₂O₅ kg⁻¹ level of SSP+lime, indicating that the mycorrhizal dependency of the host was eliminated by the highest soluble P concentrations in the soil.