جستجوی مقالات مرتبط با کلیدواژه « pinus eldarica » در نشریات گروه « علوم پایه »

Biological activities are underlying strategies against dust storms. The leaves, because of the larger surface in comparison with other parts of plant organs, are considered importantly for atmospheric dust filtration. The main purpose of this study was to compare the amount of dust deposited on the leaf surfaces of Quercus castaneifolia, Platanus orientalis, Pinus eldarica, and Ailanthus altissima in Chitgar Forest Park. Leaf samples were collected randomly from different heights of 5 individual trees in four main directions and washed thoroughly by distilled water. Dust particles of the solutions were dried-oven and were weighed. The leaf area was measured by Image J software. Results showed that dust precipitation on the leaves of pine trees are significantly higher compared to broadleaved trees. The average amount of precipitated particulate material was measured as 1.06 mg/cm2 in pine trees compared to 0.2, 0.23, and 0.28 mg/cm2 for Tree of heaven, Oak and Plane trees, respectively. Also, the area to perimeter ratio of studied species was lowest for pine (0.05) and the broadleaved species was calculated as 1.03, 1.02, and 1.55 respectively. Totally, our results showed that pine trees can better absorb the clouds of dust from the air.

Municipal effluents can often contain significant concentrations of organic and inorganic nutrients. There is potential for these nutrients to be used as a fertilizer source when the water is recycled as an irrigation source. Therefore, long-term irrigation with municipal effluents can add large amounts of nutrients to the soil and plant. A case study was undertaken to assess the impact of municipal effluent irrigation on macro and micro-nutrient (N, P, K, Ca, Mg, Fe, Mn, Cu, Zn) concentration of soil and leaf of eldar pine (Pinus eldarica Medw.) trees, in south of Tehran.
For this purpose, Data were collected using technique of systematic random sampling with 4 replicates in two 15 year-old-artificial eldar pine stands 1) under irrigation of municipal effluent and 2) irrigated with well water. Municipal sewage and well water were sampled daily (3 days in each month) from early June to late November.
Results indicated that the concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) in municipal effluent and leaf of trees irrigated with municipal effluent were significantly greater compared with those of well water treatment. Application of municipal effluent resulted in a 1.5-fold increase in the concentrations of soil macro and micro-nutrients. The nutrients showed their greatest values in the upper layer of soil (0-15 cm). Irrigation using municipal effluent did not result in toxicity of nutrients in tree leaf and soil. The macro and micro-nutrient contents of leaf were correlated with their respective value in soil.
It might be concluded that the municipal effluents could be utilized as a source of water and nutrients in afforestations.

In this investigation effect of hormonal preparation on seed germination and early growth of Pinus eldarica Medw. under salinity stress was examined. The seeds were treated with salicylic acid (0 (control)، 0/5، 1 and 2 mM، 72 hours) and following the imbibing to NaCl (0، 40، 120، 200 and 280 mM) placed in germinator (20°C) for 40 days. Germination in non-treated seeds was ceased in osmotic potentials >120 mM but it continued to 280 mM osmotic potential in treated seeds. In most salinity levels the greatest seed germination and germination energy، and in all salinity levels، the maximum of germination speed and vigor index allocated to 1 mM salicylic acid. These findings imply that for plantation of P. eldarica on saline soils it is better that the seeds before sowing in nurseries، with salicylic acid، particularly with 1 mM solution are treated

The simplest and most economical technique to reduce CO2 of atmosphere and climate regulation is carbon sequestration in plant and soil by development of vegetation and green space. Impact of afforestation and soil fertility on soil carbon sequestration and climate regulation was investigated, in two 15-year old stands of needle-leaved (Pinus eldarica) and broad-leaved (Robinia pseudoacacia) in 2 areas with different irrigation treatments (municipal effluent and well water) and also a control area (without afforestation), in an arid zone (south of Tehran). For this purpose, sample plots (30 m × 30 m) were systematic-randomly chosen in either of both stands. In each sample plot, four soil profiles were dug to take the samples in depths of 0-15, 15-30 and 30-60 cm. In laboratory, soil organic carbon (SOC) content of soil samples was determined by the Walkley–Black method. The results demonstrated that in each stand there was a significant difference (p<0.01) in the amount of soil carbon sequestration between two irrigation treatments (municipal effluent and well water). No significant difference in the amount of soil carbon sequestration of two stands was detected, but each stand sequestered higher carbon content in soil compared to that of in control area. In two studied stands, with increasing of soil carbon content, growth parameters and biomass significantly (p<0.01) were increased. With regard to more average of wood biomass and carbon sequestration and be evergreen of elder pine trees, can say that afforestation of eldar pine in comparison with block locust has more role in decreasing of air pollution and climate regulation.

The effect of different culture media and 6-Benzylaminopurin (BAP) concentrations on direct adventitious shoot formation in Pinus eldarica zygotic embryo explants were evaluated. Statistical analysis of data showed a significant media and BAP concentration effect on shoot meristem induction. Among the used basal media, Le Poivre (LP) medium supplemented with 5 mg/L BAP proved to be most suitable for multiple shoot formation. The caulogenesis occurred mainly on the basal portions of the cotyledons and without any obvious intermediate callus formation. However, the shoot regeneration process involved the identification of either shoot meristems or caulogenic nodules on the surface of cultured embryos. Histological sections confirmed the direct formation of these discrete structures on the explants. All of the adventitious shoot meristems showed normal cell organization. This in vitro procedure could be useful for studies on efficient plant regeneration of Pinus eldarica.