The impacts of Dust and Sand Storms (DSS) on people, crops, livestock, infrastructure and health are well documented. Data have accumulated on the deleterious effects of dust aerosols when they settle on plants. Sand blasting of low growing plants is a common cause of failure in reforestation efforts. Burial of plants by moving sands are also a cause of much damage. The physics of moving sand a...

A reduction in leaf stomatal conductance (g) with increasing leaf-to-air difference in water vapour pressure (D) is nearly ubiquitous. Ecological comparisons of sensitivity have led to the hypothesis that the reduction in g with increasing D serves to maintain leaf water potentials above those that would cause loss of hydraulic conductance. A reduction in leaf water potential is commonly hypoth...

the impacts of dust and sand storms (dss) on people, crops, livestock, infrastructure and health are well documented. data have accumulated on the deleterious effects of dust aerosols when they settle on plants. sand blasting of low growing plants is a common cause of failure in reforestation efforts. burial of plants by moving sands are also a cause of much damage. the physics of moving sand a...

terminal drought stress during grain filling period has recently become more common in the semiarid mediterranean regions, where wheat (triticum aestivum) is grown as an important winter cereal crop. the objective of this experiment was to study the effect of terminal drought stress on grain yield, gas exchange variables, and some physiological traits of nine bread wheat cultivars. an experimen...

The influence of red light and ultraviolet (UV)-A radiation on the single leaf photosynthesis and transpiration were investigated in two different plant-type rice cultivars: active tillering type, Hopumbyeo (HP) and low-tillering heavy panicle type, Shindongjinbyeo (SDJ) at maximum tiller number stage. An open photosynthesis measurement system was used to monitor CO2 exchange rate, which was de...

A closed system was designed for concomitant determination of net CO(2) uptake, transpiration, and foliar nitrogen (N) loss in soybeans (Glycine max [L.] Merr.). The CO(2) uptake was monitored by infrared analysis of system air removed periodically in aliquots. Leaf vapors were trapped in calibrated tubes at Dry Ice temperature, and transpiration rate was determined from the quantity of condens...

The natural (15)N/(14)N isotope composition (δ(15)N) of a tissue is a consequence of its N source and N physiological mechanisms in response to the environment. It could potentially be used as a tracer of N metabolism in plants under changing environmental conditions, where primary N metabolism may be complex, and losses and gains of N fluctuate over time. In order to test the utility of δ(15)N...

the possible alleviating effects of salicylic acid on protection of cowpea (vigna unguiculata) cv. parastu under water stress conditions were investigated in the university of zanjan agriculture research station during 2008. water stress was imposed by withholding irrigation at 50% flowering (flowering water stress, fws) and when 50% of the pods grew 2-3cm (pod-formation water stress, pfws). sa...

Knowledge of the location and magnitude of the resistance to water flow in a plant is fundamental for describing whole plant response to water stress. The reported magnitudes of these resistances vary widely, principally because of the difficulty of measuring water potential within the plant. A number of interrelated experiments are described in which the water potential of a covered, nontransp...