Materials and strategies The soil was analyzed in layers as a lot as eighty cm in two Pinus forests, one at the end of the first cultivation and other at the end of the third successive crop, in a subtropical area in southern Brazil. Stocks of exchangeable and semi-total fractions of K, Ca, and Mg within the soil have been calculated, and the potential number of crop rotations of Pinus without fertilization was estimated. Results and discussion After three Pinus crops, there was a median discount of 46.9, 90.eight, and 45.5% of exchangeable K, Ca, and Mg fractions respectively. Semi-total Ca content reduced in all depths, and semi-total K contents, in turn, solely decreased till 20 cm of depth. The semi-total Mg contents have not been modified over the cultivations.
Hyphae of ectomycorrhizal fungi do not penetrate individual cells throughout the root. Ectomycorrhizas consist of a hyphal sheath, or mantle, overlaying the foundation tip and a hartig web of hyphae surrounding the plant cells within the root cortex. Called mycorrhizae (fungus-roots), which greatly improve the efficiency of nutrient and water uptake. Trees require an adequate dose of important elements for proper growth and improvement. Lack of these might trigger stunted, gradual and less than optimum development.