الفهرس | Only 14 pages are availabe for public view |
Abstract P. dioscoridis distributes in many locations (Mediterranean, and inland (semi-arid and arid)) with different environmental conditions. The data of climate and soil revealed the ability of this plant to survive under a wide range of edaphic factors and a warm moist climate. By applying soil analysis, classification and ordination vegetation analysis and the correlation of P. dioscoridis with all environmental parameters, we can conclude that P. dioscoridis populations are mainly affected by two major categories of environmental factors: a positive effect of water related factors (represented by total soil water content, claypercentage, organic matter, precipitation, relative humidity and dew point) and a negative effect of salinity (represented by chloride, conductivity, sodium chloride percentage, potassium, sodium and calcium). P. dioscoridis and its association with halophytes can be an indicator of an environmental system exposed accidently, periodically or permanently to amounts of water. Although the high distribution of P. dioscoridis over wet habitats due to its massive production of seeds and high longevity of it, the produced seeds are strongly affected by the maternal environmental factors as climate (precipitation, relative humidity, temperature, temperature range), salinity (conductivity, TDS, sodium chloride percentage, chloride and calcium) and nutrients (nitrogen and phosphorus) at its viability, germination, establishment and fitness. Viability and dormancy of seeds need more intensive study to explain the strange behavior of it with the tetrazolium test which may be not sufficient. The response of P. dioscoridis traits to climate warming has showed an adaptive change at morphological, physiological, and anatomical levels. However, the plant is more sensitive to the climate factors than the soil factors. Warming and water availability lead the magnitude and direction of changes in plant traits. The combined effect of more than one stress on the plant leads to a different response. The response of reproductive output to the climatic changes needs more investigations for more obvious understand. The tolerance of P. dioscoridis to air pollution needs more investigations. Depending on the common garden experiment, we can conclude that P. dioscoridis can be considered a highly plastic plant and at the same time it had some adaptive traits suitable for its maternal environment. The studied traits of the plant have high plasticity as well as a considerable genetic component. As a result, it is expected that P. dioscoridis will be able to cope with a wide range of expected climate change and has a high capability to invade different habitats. |