To permit an assessment of the relative contributions of the transsulfuration and the direct sulfhydration pathways for homocysteine biosynthesis, the time course of incorporation of (35)S from (35)SO(4) (2-) into various sulfur-containing compounds in Lemna paucicostata has been determined. Plants were grown with either low (4.5 micromolar) or ample (1,000 micromolar) sulfate in the medium. At...

A new phytotoxicity test method based on root elongation of three Lemna species (Lemna gibba, L. minor, and L. paucicostata) has been developed. Tests with aquatic plants have, typically, favored measurements on fronds (e.g. frond number, area, biomass) rather than on roots, due, in part, to issues associated with handling fragile roots and the time-consuming procedures of selecting roots with ...

Glutamate dehydrogenase (L-glutamate: NAD+ oxidoreductase (deaminating) EC 1.4.1.2) has been purified to homogeneity from Lemna minor and seeds of Pisum sativum. As established by polyacrylamide gel electrophoresis the Pisum-enzyme constitutes a multiple pattern of seven charge isoenzymes whereas the Lemna enzyme shows one single protein band. Molecular weights of 230 000 were calculated for bo...

A method is described for measuring the rate constants of both synthesis and degradation of nucleic acids in sterile growing cultures of Lemna minor which avoids the difficulties of environmental changes in isotope uptake and precursor pool size. In fast growing cultures the half-life of ribosomal RNA has been estimated to be between 5 and 8 days.This half-life has been shown to consist of two ...

Recent findings indicate that plant-root exudates can stimulate plant-associated microorganisms to enhance the biodegradation of contaminants in constructed wetlands. To understand this process, we studied root-exudation changes two aquatic plants (Lemna minor and Salvinia natans) upon micropollutants exposure (10, 100 1000 ?g/L mixes containing naproxen, diclofenac, carbamazepine, benzotriazol...

The article presents the results of studies a series species identifications genus Lemna (Lemnaceae) conducted in 2019. Duckweed samples were taken from eight localities northern regions Ukraine and identified to using morphological molecular markers (barcoding). A new alien duckweed for Ukraine—lesser (Lemna aequinoctialis Welw.)—was discovered, which this study is devoted. All other belonged ...

Nutrients can determine the outcome of the competition between different floating plant species. The response of floating plants to current phosphorus levels may be affected by previously experienced phosphorus concentrations because some species have the ability to store excess phosphorus for later use. This might have an impact on their competition. Here, we investigate the effect of previous...