Introduction Conclusions References

The appearance of stomatal pores during plant evolution is believed to have been a crucial step in land colonisation. A recent screen for genes involved in stomatal development has identified for the first time a mutant plant with no stomata; the results implicate a MAP kinase cascade in stomatal development.

BACKGROUND Stomatal guard cells monitor and respond to environmental and endogenous signals such that the stomatal aperture is continually optimised for water use efficiency. A key signalling molecule produced in guard cells in response to plant hormones, light, carbon dioxide and pathogen-derived signals is hydrogen peroxide (H(2)O(2)). The mechanisms by which H(2)O(2) integrates multiple sign...

Incipient stomata might have appeared in thalloid alga-like land plants as sporophytic structures homologous to gametangial conceptacles of their isomorphic gametophytes and developed in association with vascular tissue and cuticle. Historically, stomatal evolution is correlated with growth habits and synecological events like the early terrestrial plant expansion from wetland to dryland habita...

Ecosystems remove ozone from the troposphere through both stomatal and non-stomatal depositions. The portion of ozone taken up through stomata has an oxidative effect causing damage.We used amultiyear dataset to assess ozone deposition to a ponderosa pine plantation near Blodgett Forest, Georgetown, California. Environmental parameters, water and ozone concentrations and fluxes were measured co...

Red and blue light are both vital factors for plant growth and development. We examined how different ratios of red light to blue light (R/B) provided by light-emitting diodes affected photosynthetic performance by investigating parameters related to photosynthesis, including leaf morphology, photosynthetic rate, chlorophyll fluorescence, stomatal development, light response curve, and nitrogen...

T he central roles of potassium channels in regulating membrane potential and controlling action potential repolarization are well documented (1). In plants an additional important function of potassium channels in mediating long-term potassium transport during cell movements, turgor changes, and tropisms has been proposed. Two guard cells surround each stomatal pore in leaves and control the o...

Stomata are small adjustable pores formed by pairs of guard cells that enable gas exchange between leaves and the atmosphere, thus directly affecting water loss and CO2 uptake in plants. The current work focuses on the regulation of stomatal movements by red light, carbon dioxide and the circadian system and attempts to uncover molecular mechanisms that control guard cell function. The signalin...

Isoprene emission in relation to stomatal distribution and conductance was determined for the hypostomatous species, aspen and white oak, and the amphistomatous species, cottonwood. For aspen and oak, isoprene emission from the adaxial (nonstomatal) surface was <2% of that from the abaxial (stomatal) surface, even when stomata were closed by addition of abscisic acid (ABA). When treated with AB...