Distribution profiles of selected micronutrients in oriental field‐grown tobacco plants as affected by nitrogen fertilization

Abstract

In an attempt to investigate nitrogen (N)‐fertilization which is considered incompatible with oriental tobacco agricultural practice, the influence of N‐fertilization (no fertilization or ammonium nitrate fertilizer applied at either 50 or 100 Kg N ha^‐1) the growth stage (plant age) and the stalk position (basal, middle, and upper) on the micro‐nutrient concentration distribution in leaves of the oriental tobacco cv. Myrodata Agriniou was studied. All investigated factors affected, I) the leaf micro‐nutrients concentrations and leaf dry matter of field grown tobacco plants in the following order of decreasing strength: N‐fertilization level > growth stage > leaf position and ii) the stem micro‐nutrients concentrations and dry matter accumulation in the order: stalk position > growth stage > N‐fertilization level. Both N‐fertilization level and growth stage were positively correlated with dry matter accumulation, but negatively with zinc (Zn) and copper (Cu) accumulation. In addition, N‐fertilization was negatively correlated with manganese (Mn) concentration, while the same was true for the correlation of growth stage with iron (Fe). With the exception of Mn, leaf position was negatively correlated with every parameter investigated. Stem micro‐nutrient concentration were lower than those of the leaves. Manganese showed the higher differences in concentration level between leaves and stems. It is concluded that N‐fertilization delays leaf maturing and senescence, increases leaf size, as well as the leaf fresh weight and the micro‐nutrients accumulation especially in the basal leaves.