INTENSITY OF ACCUMULATION OF HEAVY METALS IN LEAF MASS AND SEEDS OF MILK THISTLE FOR ORGANIC FERTILIZER

Abstract

The impact of organic feeding of milk thistle on the intensity of accumulation and accumulation factors in the mass and seeds of lead, cadmium, zinc and copper was studied. The use of organic fertilizers in crop production is an important measure in increasing the volume of production and improving its quality. However, the use of organic fertilizers also contributes to soil pollution with heavy metals, which can accumulate in plants several tens of times higher than in the soil. It is known that with such organic fertilizers as humus and defecate, with each kilogram, 3.3 mg and 28 mg of lead, 0.2 mg and 0.18 mg of cadmium, 12.1 mg and 22 mg of zinc, respectively, enter the soil. and 19.8 mg and 6.3 mg copper. As a result of the studies, it was found out that the cultivation of milk thistle in the conditions of modern agricultural land retains a high level of accumulation of lead, cadmium, zinc and copper in the leaf mass and seeds, which requires constant monitoring of the content of these toxicants in this raw material. According to the research results, it was found that feeding milk thistle with organic fertilizers increases the accumulation coefficient of lead, cadmium, zinc and copper in its leaf mass and seeds, especially when using humus and defecate, there is relatively less use of green manure. Whereas the cultivation of milk thistle after a four-year-old predecessor of alfalfa without the use of feeding this crop in this period makes it possible to cleanse the soil from heavy metals due to phyto-remediation and reduce the concentration of lead, cadmium, zinc and copper in the leaf mass and seeds below the maximum permissible concentrations.