PLANT AND ECOSYSTEM
Year:2009 | Volume:4 | Issue:16|Papers Count:8

This research was done in the salt desert of south of Varamin (Tehran) .This region with an area of 16 Km2, situated in south Varamin.The soil of region including; lume, clay, silt, with salt and alkalin pH. Karaj and Brackish rivers situated in this region. The altitude of this region is 850 meters high from sea level and annual averege of precipitation reaches to 172.28 mm. Flora of this region includes 41 plant species that belong to 30 genera and 11 families. The important families considering that number of species are Chenopodiaceae, Tamaricaceae & Poaceae with 15 (36.58%), 6 (14.63)& 6 (14.63) species respectively. Tamarix with 6 and Salsola with 4 species are the largest genera. Life forms of the plant species of region include: therophyte 53.66%, phanerophytes 19.51, chamaephytes 12.19%, hemichryptophytes 7.32%, geophytes 4.88% and holophytes 2.44%. From the view point of regional elements plants of this region include: 39.02% IT, 19.51% IT; SS, 14.63% Cosm, 9.76% IT; SS; M, 9.76% IT; M; ES, 4.88% IT; ES, 2.44% IT; M .

The genus Vicia L. is an important genus of the Fabaceae family which is predominantly distributed with some 180 to 210 species in the world. V. sativa is one of the valuable forage plants in this family. The flora Iranica is described four variety of this specimen such as: V. sativa var. amphicarpa, V. sativa var. sativa, V. sativa var. angustifolia and V. sativa var. cordata.64 specimens collected from Tehran and different parts of northern provinces related to V. sativa. High different morphological variety of this specimens was showed. This variety specially observed in foliolate characters such as form and number, stem transaction, corolla characters and seed forms. Also basic chromosome number in V.sativa and V.angustifolia is n=6 and in V. cordata is n=5. According to the obtained results, it is suggested that, V. cordata and V.angustifolia must be changed from variety to species level.

Forests have very important role in equilibrium of food chains and healthy of living organisms. Diverse flora of different trees and shrubs are scattered in different regions of Iran which many of them are rare species of the world. The forest trees and shrubs have several pests which wood-boring beetles (Coleoptera: Cerambycidae, Buprestidae, Lucanidae) are the most important pests for these plants. The present research was conducted to determine the wood-boring beetles of forest trees and shrubs through 2000-2006 in different regions in Iran. The results indicated that totally 48 host plants were identified for 85 wood-boring beetles. Of the several host plants, three families including, Rosaceae, Ulmaceae, and Fagaceae with 19, 8 and 6 plant species, respectively had the highest number of host plants for wood-boring beetles. In addition to the host plants of wood-boring beetles, many important and dominant natural enemies (predators and parasitoids) were collected and determined from the studied regions.

To study the effect of plant density and Nitrogen fertilizer on seed morphological characteristics in milk thistle, an experiment was conducted in spring of 2005 at research station of Hammand Absard. After harvest, seeds were placed in suitable storage for a year. Then traits included 1000 seeds weight, germination percentage, wet weight, dry weight of seed ‏ ling, coleoptiles, colorize and seedling longevity were assessed.The results showed that by increasing the mother’s plant growth that rains by decreasing the plant density and increasing of N-fertilizer, seed yield increased, so it increases the percentage of seed ‏germination, seedling longevity, wet and dry weight of seedling and we could obtain highest amounts of: 1000 seeds weight (23.3g), germination percentage (97%), wet seedling weight (80.72 mg) and seedling dry weight (4.81mg) in plot with plant density of 5 plant per square meter and 150 kg/ha of nitrogen fertilizer and lowest amount of above factors respectively (22.4g), (81%), (58.61mg) and (4.04mg) in plot with 10 plant per square meter and with ‏ out any nitrogen fertilizer.

Increasing prevalence of antibiotic-resistant bacteria has led to a demand for new agents that could be used to decrease the prevalance of disease. Cumin can be a good option for this purpose. The objective of this study was to investigate the effect of chemical and organic fertilizers on quality and antibacterial activity of cumin essential oil. Seeds were treated with different fertilizers during sowing. The essential oil was prepared by water distillation and analyzed by GC/Mass gas chromatography. The antibacterial activity was determined by disk diffusion method. Results indicated that A2 treatment increased the quality of essential oil by increasing the amount of b-pinene. The cumin essential oil showed significant antibacterial effects and Gram positive bacteria showed more susceptibility than gram negative ones. As a result, the cumin essential oil could be a good substitute to eliminate bacteria.

To study the effect of no irrigation from stem ‏ elongation stage on agronomical characteristics grain and oil yield of winter rapeseed cultivars, a research was done in case of factorial experiment in form of random complete block basis design in three replications in which the irrigation in two levels ‏ consist of normal irrigation (witness) and no irrigation from stem ‏ elongation stage and cultivar in five levels ‏‏ consist of Okapi, Zarfam, Orient, Talaye, SLM046 cultivars.This experiment was conducted on crop year 1385-86 in the 400 hectar of field of research, breeding and producing of seed and plant institute of karaj.The results showed that the effect of simple of irrigation on characters number of silique in plant, length of silique, seed yield and yield of grain oil in one percentage level and on characters number of grain in silique and weight of 1000 grain in five percentage level were significant. The effect of simple of cultivar also on characters number of silique in plant, length of silique, seed yield and yield of grain oil in one percentage level and for weight of 1000 grain character in five percentage level were significant. Also The effect of interaction of irrigation and cultivar on characters number of silique in plant, seed yield and yield of grain oil in one percentage level were significant.On the basis of the results, that Zarfam cultivar in both normal irrigation condition (witness) and also in drought stress condition had the higher grain and oil yield. According to agronomy ‏‏ tube used in drought stress condition has been recormmended.

Zn deficiency has been reported for some crops in Iran.The published reports indicated that Zn recovery from fertilizers is very low.This means that a considerable portion of applied Zn is not absorbedly by the first plant and thus could be used by sub sequence crops.The objectives of the present experiment were to study: (i) The effects of residual Zn on growth and Zn concentration and uptake by wheat (Triticum aestivum L.), (ii) Growth and Zn concentration and uptake as affected by Zn chemical forms.Based on the last study twenty surface soil samples (0-30cm) from major paddy rice fields in Fars province were used and treated with 3 levels of Zn (0, 5, 10 mg/kg soil as ZnSO4.7H2O) then planted to rice (first crop). Pots were replanted to rice (second crop)and the wheat (third crop), respectively. Shoot dry weight, relative growth and Zn concentration and uptake were used as plant responses. Soil samples were taken before wheat and extracted. In addition, chemical forms of native and applied Zn were determined by sequential fractional method.The results indicated that although residual Zn had no significant effect on dry matter of wheat, it markedly increased Zn concentration and uptake by this crop.The results of present study also shown that 33 – 42% of applied Zn was converted to carbonate form. It indicated that this form is responsible for the observed residual effect of ZnSO4 in these calcareous soils.Multiple regression equations revealed that the carbonate form was significantly correlated with dry matter, Zn concentration and uptake and relative yield of wheat. The regression equations were also run in soil samples before the third crop.

This Expriment carried out in compeletly block desine in 8 paddies of Mazandaran province to determine the effect of KCl fertilizer on Neda rice variety.After selecting fieldes, land perepreation was done on the base of the traditional methods in farming.The dimention of plot was 3 * 4 meters.Soil sample was provided from each plot and necessary tests have done on the basis of current methods of soil and water research inistitute.Urea and triple super phosphate were used on farmers conventional norms.The test included 6 treatment (0, 100, 200, 300, 400, 500kg/ha) KCl, half of this as base application the other half as sidedress.The result of experiment showed that the effect of different rate of KCl fertilizer on grain yield was significant (1%level).The range of grain yield increase in paddies that yielded significantly due to Kcl fertilizers (63%) were between 600 to 2800 kg/ha (7%to 32%). The best potassium fertilizer treatment for Neda variety was calculated 300 kg/ha in west paddies of Mazandaran province.