The mechanisms by which higher plants recognize and respond to sugars are largely unknown. Here, we present evidence that the first enzyme in the hexose assimilation pathway, hexokinase (HXK), acts as a sensor for plant sugar responses. Transgenic Arabidopsis plants expressing antisense hexokinase (AtHXK) genes are sugar hyposensitive, whereas plants overexpressing AtHXK are sugar hypersensitiv...

Iran has a long history in the use of medicinal plants and traditional medicine. Local people in the villages, especially the elderly, have useful information about health benefits and how to use these plants. Therefore, it seems that collecting and recording this information leads to the revival of this traditional knowledge. The current research is an ethnobotanical study on the medicinal pla...

the identification of molecular markers linked to leaf curl virus (clcuv) disease resistance in cotton has the potential to improve both the efficiency and the efficacy of selection in cotton breeding programs. genetic analysis suggested that clcuv resistance is controlled by a single dominant gene. in this study, an interspecific f2 population derived from a cross of gossypium barbadense and g...

     Roads have an important role in plants dispersal on different scales. Various plant species settle on roadsides, but some of them can enter the natural environments and threaten their biodiversity. Worldwide knowledge of roadside flora is necessary for local and global management of natural areas. Accordingly, the roadside flora of Northern Khorasan rangelands was studied along the 600 km ...

This experimental study tests new theory for multiple predator effects on communities by using warming to alter predator habitat use and hence direct and indirect interactions in a grassland food web containing two dominant spider predator species, a dominant grasshopper herbivore and grass and herb plants. Experimental warming further offers insight into how climate change might alter direct a...

H erbicide resistance is the inherited ability of a plant to survive and reproduce following exposure to a dose of herbicide that would normally be lethal to the wild type. In a plant, resistance may occur naturally due to selection or it may be induced through such techniques as genetic engineering. Resistance may occur in plants as the result of random and infrequent mutations; there has been...

Plants grown in contaminated areas may accumulate trace metals to a toxic level via their roots and/or leaves. In the present study, we investigated the distribution and sources of Pb and Cd in maize plants (Zea mays L.) grown in a typical zinc smelting impacted area of southwestern China. Results showed that the smelting activities caused significantly elevated concentrations of Pb and Cd in t...

A tetracycline-inducible promoter system was used to generate transgenic tobacco plants that confer inducible expression of the wild type or a dominant negative allele of the gene coding for the cyclin-dependent kinase (CDK) of Arabidopsis thaliana CDC2aAt. Although the total extractable CDK activity was doubled, the induced expression of the wild-type CDC2aAt did not correlate with any change ...

Climate change effects on snow cover and thermic regime in alpine tundra might lead to a longer growing season, but could also increase risks to plants from spring frost events. Alpine snowbeds, i.e. alpine tundra from late snowmelt sites, might be particularly susceptible to such climatic changes. Snowbed communities were grown in large monoliths for two consecutive years, under different mani...