Goldstein, M. ; Malchi, T. ; Shenker, M. ; Chefetz, B. Pharmacokinetics in Plants: Carbamazepine and Its Interactions with Lamotrigine.
Environmental Science & Technology 2018,
52, 6957 - 6964.
Publisher's VersionAbstractCarbamazepine and lamotrigine prescribed antiepileptic drugs are highly persistent in the environment and were detected in crops irrigated with reclaimed wastewater. This study reports pharmacokinetics of the two drugs and their metabolites in cucumber plants under hydroponic culture, testing their uptake, translocation, and transformation over 96 h in single and bisolute systems at varying pH. Ruling out root adsorption and transformations in the nutrient solution, we demonstrate that carbamazepine root uptake is largely affected by the concentration gradient across the membrane. Unlike carbamazepine, lamotrigine is adsorbed to the root and undergoes ion trapping in root cells thus its translocation to the shoots is limited. On the basis of that, carbamazepine uptake was not affected by the presence of lamotrigine, while lamotrigine uptake was enhanced in the presence of carbamazepine. Transformation of carbamazepine in the roots was slightly reduced in the presence of lamotrigine. Carbamazepine metabolism was far more pronounced in the shoots than in the roots, indicating that most of the metabolism occurs in the leaves, probably due to higher concentration and longer residence time. This study indicates that the uptake of small nonionic pharmaceuticals is passive and governed by diffusion across the root membrane.Carbamazepine and lamotrigine prescribed antiepileptic drugs are highly persistent in the environment and were detected in crops irrigated with reclaimed wastewater. This study reports pharmacokinetics of the two drugs and their metabolites in cucumber plants under hydroponic culture, testing their uptake, translocation, and transformation over 96 h in single and bisolute systems at varying pH. Ruling out root adsorption and transformations in the nutrient solution, we demonstrate that carbamazepine root uptake is largely affected by the concentration gradient across the membrane. Unlike carbamazepine, lamotrigine is adsorbed to the root and undergoes ion trapping in root cells thus its translocation to the shoots is limited. On the basis of that, carbamazepine uptake was not affected by the presence of lamotrigine, while lamotrigine uptake was enhanced in the presence of carbamazepine. Transformation of carbamazepine in the roots was slightly reduced in the presence of lamotrigine. Carbamazepine metabolism was far more pronounced in the shoots than in the roots, indicating that most of the metabolism occurs in the leaves, probably due to higher concentration and longer residence time. This study indicates that the uptake of small nonionic pharmaceuticals is passive and governed by diffusion across the root membrane.
Seth, A. ; Gothelf, R. ; Shenker, M. The K to (Ca+Mg) ratio effect on potassium availability for plants - splitting soil- from plant-related interactions. In
EGU General Assembly Conference Abstracts; EGU General Assembly Conference Abstracts; 2018; Vol. 20, pp. 9425.
Rotbart, N. ; Guetta, Y. ; Oren, A. ; Laor, Y. ; Raviv, M. ; Medina, S. ; Levy, G. ; Yermiyahu, U. ; Shenker, M. ; Bar-Tal, A. Organic management effects on the dynamics of soil organic carbon and nitrogen pools. In
EGU General Assembly Conference Abstracts; EGU General Assembly Conference Abstracts; 2018; Vol. 20, pp. 12033.
Shenker, M. ; Seth, A. Potassium availability in soils and the use of the Q/I approach - moving from theory to nation-wide realization. In
EGU General Assembly Conference Abstracts; EGU General Assembly Conference Abstracts; 2018; Vol. 20, pp. 9716.
Zimerman-Lax, N. ; Tamir-Ariel, D. ; Shenker, M. ; Burdman, S. Decreased potassium fertilization is associated with increased pathogen growth and disease severity caused by Acidovorax citrulli in melon foliage.
Journal of General Plant Pathology 2018,
84, 27 - 34.
Publisher's VersionAbstractThe gram-negative bacterium Acidovorax citrulli causes bacterial fruit blotch (BFB) disease of cucurbits, which represents a serious threat to melon and watermelon production worldwide. To date, there are no efficient means to manage the disease, and reliable resistance sources for cucurbit germplasm are lacking. Mineral nutrition markedly affects plant diseases. Recently, we reported that disease severity on melon foliage and A. citrulli growth in the leaf tissue were significantly influenced by the form of nitrogen supply. In the present study, we investigated the influence of potassium nutrition on BFB severity and A. citrulli establishment in the foliage of melon plants. Fertilization with relatively low concentrations of potassium increased these variables compared with higher potassium concentrations. Since establishment of A. citrulli during the growing season is assumed to increase the incidence of fruit infection, the fact that mineral nutrition influences BFB incidence in the plant foliage is of particular importance.