THE EFFECTS OF HUMIC ACID APPLICATION ON THE NUTRIENT CONTENTS AND HEAVY METALS IN ORGANS OF MARIGOLD (TAGETES ERECTA L.)

This study investigated the effects of humic acid doses applied directly to the soil (control, 10, 20, 40 kg da-1) wherein yellow and orange tagates species were grown. The effect of humic acid on the concentrations of macro elements, micro elements and heavy metals in stalk, leave and flower were determined. At the end of the study, it was observed that applying humic acid had a significant effect of 0.1% on the concentrations of N, P, K, Mg, Na, Fe, Zn, Cu, Mn, Cd, Ni, and Pb. Additionally, there were significant differences seen in the nutritional elements content in plant organs, with N, K, Ca, Mg, Na, Fe, Zn, Cu, Mn, Cd, Ni, and Pb at a percentage of 0.1% and P at a percentage of 1%. It was observed that there was a significant difference of 0.1% in regards to the nutrient content of the elements K, Na, Zn, Cu, and Pb. There were no observable significant differences in the amount of the other elements. To conclude, it was determined that applying humic acid had a significant effect on the element contents of different tagates species as well as the nutritional element and heavy metal contents of plant species and their organs.