CORRELATION BETWEEN SOIL CHARACTERISTICS AND IRON CONTENT IN ABOVEGROUND BIOMASS OF VIRGINIA TOBACCO

摘要

The study was conducted on alluvial-meadow, maroon-forest soils and vertisols with Virginia tobacco. The total content of iron was measured through decomposition by HF, HCIO and HNO acids. A solution of 0.005 M diethylentriaminepentaacetic acid + 0.1M triethanolamine, pH 7.3 was used for extraction of the elements’ mobile forms from soils. The plant sample preparation was made by means of dry ashing and dissolution in 3 M HCl. A Varian Spectra AA 220 Atomic Absorption Spectrophotometer was used forFe content determination in soil and plant samples. Certified reference materials (three types of soils and tobacco leaves) were also analyzed for accurate determination of Fe concentrations. A correlation and regression analysis was conducted between pH, humus content, total and mobile iron forms in the soil, and the concentration of these elements in aboveground biomass of Virginia tobacco. It was estimated that there were statistically significant relationships between soil pH and iron concentrationin Virginia tobacco plant organs. The correlation - regression analysis results showed that there were no statistically significant relationships between humus and iron concentration in aboveground tobacco biomass of Virginia tobacco. Also, the resultsof the correlation - regression analysis showed that there were no statistically significant relationships between the total element content in soils and iron content in aboveground tobacco biomass of Virginia type. Regression relationships were established between movable iron in the soil and element content in leaves from the lower, middle and upper harvesting zones.