Uptakes of o-chlorophenol (CP), 2,4-dichlorophenol (DCP), trichloroethylene (TCE), and atrazine (ATR), as single and mixed contaminants, by roots and shoots of rice seedlings (Oryza sativa L.) from hydroponic solutions were measured following a 48-h exposure of plant roots. As single contaminants, the concentrations of CP, DCP, and ATR in rice roots and shoots increased significantly with incre...

Plant roots release about 5% to 20% of all photosynthetically-fixed carbon, and as a result create a carbon-rich environment for numerous rhizosphere organisms, including plant pathogens and symbiotic microbes. Although some characterization of root exudates has been achieved, especially of secondary metabolites and proteins, much less is known about volatile organic compounds (VOCs) released b...

Nerve cells are complex cells with highly specialized functions. Not only are nerve cells from different regions of the nervous system functionally heterogeneous, but each individual cell also contains distinct regions that perform specific functions. Consequently, the nerve cell soma, dendrites and axons all express different proteins that are required for the specific tasks they perform, maki...

Human urine is a potential alternative fertilizer for agriculture. However, its usage is associated with a risk of spreading pharmaceutical residues to fields. The individual and combined behavior of carbamazepine and ibuprofen was investigated by GC/MS analysis in a greenhouse experiment using ryegrass fertilized with pharmaceutical-spiked urine. Only carbamazepine could be detected in soil, r...

This study investigated selenium uptake and transport from the soil to 12 plant species in the mining area of Gumuskoy (Kutahya), Turkey. Plant samples and their associated soils were collected and analyzed for Se content by ICP-MS. Mean Se values in the soils, roots, and shoots of all plants were 0.9, 0.6, and 0.8 mg kg, respectively. The mean enrichment factors for roots (ECR) and shoots (ECS...

The aim of this study was to investigate the effects of selenium (Se) on the growth, accumulation and possible mechanisms of Se transport in certain parts (roots, leaves, stamp and apex) of nettle (Urtica dioica L.) plants. Se was supplemented by one-shot and two repeated doses to the soil (2.0 and 4.0 mg Se per kg of substrate). Selenium content in roots increased linearly with dose and was si...

We have recently identified two genes coding for ammonium transporters (AMT) in Sorghum bicolor that were induced in roots colonized by arbuscular mycorrhizal (AM) fungi. To improve our understanding of the dynamics of ammonium transport in this symbiosis, we studied the transfer of soil-ammonium-derived (15)N to S. bicolor plants via the Glomus mosseae fungal mycelium in compartmented microcos...

Recent studies have provided significant new insights into the gene actions that specify and maintain stem cells in plant shoots and roots. New layers of genetic control and potential signalling pathways and effector mechanisms have emerged from these new studies and will be reviewed here. These new findings refine the current model in which stem cells in plant meristems are regulated by negati...

One hundred methanol plant extracts were screened for antibiotic activity against Mycobacterium tuberculosis and Mycobacterium avium. Nineteen extracts exhibited some activity against M. tuberculosis and 16 extracts showed some activity against M. avium. Thirteen of these 19 active extracts were traditionally used by First Nations peoples to treat tuberculosis. Extracts made from Heracleum maxi...

The circadian oscillator in eukaryotes consists of several interlocking feedback loops through which the expression of clock genes is controlled. It is generally assumed that all plant cells contain essentially identical and cell-autonomous multiloop clocks. Here, we show that the circadian clock in the roots of mature Arabidopsis plants differs markedly from that in the shoots and that the roo...