Nitrogen metabolism in Nicotian a rustica L. grown with molybdenum. II. flowering stage

Abstract

The effect of molybdenum application time on development and nitrogen metabolism in Nicotiana rustica L. was studied. The plants were grown in hydroponically in vermiculite. The control plants received 0.01 ppm Mo, and the treated plants received 1 ppm Mo throughout the experiment (1‐Mo lot) and 1 ppm Mo only until flowering (1‐Mo+C lot). Molybdenum supply accelerated the flowering period in N. rustica, mainly when the supply is only during the vegetative stage. Nitrate reductase activity and root nitrate content increased with molybdenum supply. In contrast, nitrate content in leaves decreased with this molybdenum dose. Both effects are independent of the molybdenum application time. Important differences between molybdenum application time in N. rustica were not observed, except in the root, where the protein content was greater in 1‐Mo+C treatment.