THE IMPORTANCE OF MYCORRHIZAL FUNGI IN CU LTURAL-PRACTICE

Many relationships arose in the process of co-evolution of plant and m icroorganisms; only a few of them are so important as mycorrhiza. Myco rrhiza represents a natural biological apparatus for overcoming a numb er of suboptimal or negative growth conditions in a great number of pl ant species in various ecosystems. In the case of field crops this is mycorrhiza of vesicular-arbuscular type (VAM). A positive action of my corrhiza on the health of plants and their productivity is based upon biocontrol protection of root against undesirable microorganisms throu gh the perfect invasion of root by mycorrhizal fungus and mediation of more effective uptake of mineral nutrients by mycelial-root system. A mong the most significant manifestations are as follows: inhibition of reproductive formations and reduction of colonization of many pathoge ns on mycorrhizal roots; significant improvement of supply of host pla nts by phosphorus and other limiting nutrients, e.g. nitrogen; greater resistance or tolerance to abiotic stresses - low pH, excessive conce ntration of some metals in environment and others. Stabilization or im provement of present mycorrhizal condition of plants can contribute to the decline in inputs into agricultural production and to limitation of production risks following from action of harmful biotic agents and abiotic stresses.