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A two year-experiment was carried out to study an effect of root inoculation with arbuscular mycorrhizal (AM) fungus on soil mineral concentrations and soil microbial activity in grapevine (Vitis vinifera) cv. "Cabernet Sauvignon" cultivated in Chile. Plants were inoculated with a commercial granular inoculant (Mycosym Tri-ton^®) and cultivated in 20 L plastic pots filled with an unsterilized sandy clay soil from the Vertisols class under climatic conditions of Curicó (34°58' S; 71°14' W; 228 m ASL), Chile.
Soil analyses were carried out at the beginning of the study and after two years (four samples of rhizospheric soil for each treatment) to assess the effects of mycorrhizal infection on soil mineral concentration and physical properties. Soil microbial activity was measured by quantifying the soil production of CO₂ in ten replications of 50 g of soil from each treatment. Root mycorrhizal infection was assessed through samples of fresh roots collected during 2005 and 2006. Fifty samples for each treatment were analyzed and the percentage of root length containing arbuscules and vesicles was assessed.
During both years (2005 and 2006) all treatments showed mycorrhizal infection, even the Control treatment where no AM was applied. Mycorrhizal colonization did not affect the soil concentrations of N, P, K, Ca, Mg, K, Ca, Mg, Mn, Zn, Cu, Fe, B, organic matter, pH/KCl and ECe. Soil CO₂-C in vitro production markedly decreased during the period of the study. No significant differences where detected among treatments in most cases.

In 2003-2007 the issue of the forage production and quality on the permanent grassland was researched by the Crop Research Institute Prague, Research Station Jevíčko. The long-term small plot trials with tall oatgrass stand type (Arrhenatherion) were established in 2003 on a fluvisoil. Four types of utilisation were used in the trial: 1. Intensive (I₁) - 4 cuts per year (1^st cut on 15^th May, every next after 45 days); 2. Medium intensive (I₂) - 3 cuts per year (1^st cut on 30^th May, every next after 60 days); 3. Low intensive (I₃) - 2 cuts per year (1^st cut on 15^th June, 2^nd after 90 days); 4. Extensive (I₄) - 2 cuts per year (1^st cut on 30^th June, 2^nd after 90 days) and four levels of fertilizer application: F₀ = no fertilization; F_PK = P₃₀K₆₀N₀; F_PKN90 = P₃₀K₆₀+N₉₀; F_PKN180 = P₃₀K₆₀+N₁₈₀. The overall average DM production of grasslands over five years was 7.19 t.ha^-1. The lowest annual DM production is 6.77 t.ha^-1 during the intensive utilisation (I₁) and it increases towards the extensive (I₄) utilisation to 7.62 t.ha^-1, at all levels of fertilization. Application of phosphorus and potash fertilizers did not have significant effects on grassland DM yield. Application of N-fertilizer increased DM production (P_0.01) already on the level F_PKN90 to 8.49 t.ha^-1, on the level F_PKN180 DM matter still increased up to 9.51 t.ha^-1. Forage quality was highest during the intensive (I₁) utilisation and relatively lowest during the extensive (I₄) utilisation. The intensive (I₁) utilisation of permanent grassland improves OMD (P_0.01), concentration of CP and NEL and decreases fiber concentration (P_0.01) when compared with the extensive (I₄) utilisation. Fertilizing did not affect quality significantly except for CP concentration which increases with N-fertilization while NEL concentration decreases. Optimal utilisation intensity for dairy cows with annual production of 7-8 thousand kg of milk seems to be the intensive (I₁) utilisation with the level of fertilization F_PKN180 for given grass stand (plant society Arrhenatheretum). The forage from the medium intensively (I₂) utilized grassland meets quality parameters for suckler cows at the end of lactation period, the forage from less intensively and extensively (I₃, I₄) utilized grassland is suitable for cows only in the dry period in the form of hay.