Investigation of Nasturtium officinale R.Br. and Mentha aquatica L. taxa reaction in different lead element concentrations

Abstract

In this study, it was aimed to determine the morphological and physiological effects of agricultural activities and lead pollution on Nasturtium officinale and Mentha aquatica macrophytes living in Umurbey Stream (Çanakkale), and also the competition between plants in this region was investigated. Macrophytes were collected between May-June 2016 from the lower part of Gökköy Passage, which is covered with orchards on both sides of Çanakkale province, Umurbey district, Umurbey Stream. The macrophytes were left in the nutrient solution for 3 days for the adaptation process. In the first stage, the effect of lead contamination on the morphology and physiology of macrophyte species was investigated in a single culture at 1, 5 and 10 ppm Pb concentrations. Then, the competitiveness of two macrophyte species at an intermediate dose of 5 ppm Pb in a mixed culture was examined. In addition to the amount of, chlorophyll a and b, carotenoid, free proline, protein, total phenolic compound amount, adsorbed lead amount and total potassium, phosphorus, iron and magnesium amounts were examined. P, Fe, Mg, K, Pb and protein content reached the highest level at the dose of 5 ppm Pb where N. officinale was affected the most morphologically. At the same time, N officinale minimized the photosynthetic pigment and free proline levels at this dose. The dose at which M. aquatica was most affected morphologically was 10 ppm Pb dose. P, Fe, Mg and K contents of M. aquatica at that dose reached the highest value. This study proved that M. aquatica was morphologically and physiologically more resistant in two control groups where there was no lead stress and aquatic plants were grown together. Morphologically and physiologically, it has been shown that N. officinale was more combative when lead was applied as stress. With this study, it was determined that watercress is a good lead accumulator by adsorbing more than twice the lead amount absorbed by water mint.