PLANT AND ECOSYSTEM
Year:2012 | Volume:8 | Issue:32|Papers Count:9

Phlomis aucheri Boiss. is an endemic species of Labiatae family which has been distributed widely in different regions of Iran. In this research, in order to compare the effect of different environmental and ecological factors in creating phonotypic plasticity, 11 different geographic populations of this species were collected from different regions including center, north-west, west and south–west also 14 qualitative and quantitative morphological traits of vegetative and reproductive organs were examined. Morphological review showed that the shape and dimensions of basal and floral leaves and dimensions of the calyx and corolla were different between populations. This case indicates that environmental and adaphic factors led to the phenotypic plasticity process in plants, which was adjustable to climatic variations that caused similarities and differences among populations. Statistical analysis was led to draw a cluster in which individuals form a special arrangement which exactly conformed to the Iranian phytogeographical regions.

One of the important issues in the arid and semi-arid regions is the soil salinity and drought. Therefore, choosing resistant species to salinity and drought especially in seed germination and emergence stages is important. This study investigated the effects of salt and drought stress on seed germination of Stipa arabica which is as palatable forage. We measured the percentage of germination, germination rate, stem and root length, seed vigor under salinity and drought stress. A completely randomised design was carried out using six salinity treatments (control, 50, 100, 150, 200 and 300 mM NaCl) and six drought treatments (control, 0.2, 0.4, 0.6, 0.8 and 1 MPa polyethylene glycol). For each treatment we used 25 seeds as replicate in Petri dish and then were germinated in gerrminator for two weeks. Results showed that salinity stress significatly influenced seed germination and as a result we found a significat reduction of percentage of seed germination, seed germination rate, stem and root length and seed vigor.

The effect of humic acid on vegetative growth of pasture Agropyron cristatum was evaluated in 2010 as a pilot in the greenhouse in Damavand, Iran. Humic acid granular fertilizer to the value of 0, 75, 150 and 225 kg per hectare was used. Correlation analysis results showed that under conditions of Cody there was a significant positive correlation among most traits. Stepwise regression analysis showed that the effect on shoot fresh weight of tillers, leaves and stem fresh weight, root length, shoot dry weight ratio of air to the roots, chlorophyll b and carotenoids, leaf, root dry weight and leaves. The increase in leaf area, chlorophyll a, chlorophyll b, chlorophyll and total carotenoids increased the degree of amount of fertilizer, the amount of each fertilizer humic acids in length, plant height, fresh weight and dry weight of roots and dry leaves of the degree of The third will follow the path analysis results indicated that the most effective traits including fresh weight, shoot fresh weight of leaf, stem fresh weight, root length, leaf dry weight, shoot dry weight ratio of air to the roots, chlorophyll b, carotenoids, and leaf were. The most appropriate amount of humic acid is 225 kg per hectare.

In this study, from the viewpoint of phyto - sociologic, the country pastures of Beneh Abad from Baft of Kerman were studied for distinguishing and determining the vegetable societies of this region which were also the most effective factor from several environmental factors. The sampling, based on the Blank - Broun School (Zurich - Mounilieh), was done by a selective method with 56 sample plots (parts) and the area of sample plots was determined by using the minimum level method. In the studied area, 48 species belonged to 40 genera and 22 families and also the biological forms were determined by Rankayar method. Vegetable cover and the environmental factors including physical, chemical and physiographic properties of soil based on the school of Broun – Blank sociological (by the method of Goonoo), bilateral analysis of index species (TWINSPAN) and the common comparative analysis (CCA) were studied. Based on the school of Goonoo method, four vegetable societies were determined as the following: Acanthophyllo glandulosei-Brometum tomentelli, Rhamnetum oleoidis, Acantholimono scorpii-Astragaloretum siliquosi, Medicagini sativae-Brometum tomentelli Using the bilateral analysis method index, in order to determine the index groups, four ecologic groups were distinguished. The most effective environmental factors in distinguishing ecologic groups based on the common comparative analysis, azoth percentage, carbon, phosphor, potassium, height from sea level and slope were determined. In studying the rate of similarity among different vegetable societies which was determined based on the Jakard similarity coefficient, it was determined that vegetable societies of this region has a relatively high variety. This issue has been indicative of environmental considerable changes or the effectiveness of different parts of this region against the resulted changes or transformations from human involvement in this region surface.

The study was carried out in Khozstan Oak forest located in southwest of Iran. The aim of this study was to determine the Qualitative and quantitative charactristics of Cerasus Mahaleb mill in relation to Some ecological characteristics of site. The plot area was 50×50 m. In this study, 72 sampling plots were taken using random-systematic method. In each plot tree species, physiographic factors and quantitative and qualitative factors of Cerasus Mahaleb (diameter at breast height, total height, trunk height, crown height, crown diameter and degree of quality and regeneration methods were obtained. The collected data were analyzed. The results showed that the Cerasus Mahaleb had the highest distribution on Clay Soil, clay - loam and sandy - clay – loam soil and in the height range 1950 -2450m above sea level, dry slopes (mostly Southwestern) and slopes from 50 to 70 and 30 -50 %. The results of qualitative and quantitative characteristics of Cerasus Mahaleb showed that trees had the poor quality. The average of DBH, the average number per hectare, The average of total height, the average of crown diameter, the average height of crown and the average volume per hectare were respectively 24.27 cm, 16.38, 6.28 m, 3.73 m., 4.57 m and 27.1 m3. Pearson correlation results showed the features of Cerasus Mahaleb such as crown diameter and tree height had a significant relationship with soil depth. The results showed that the diameter at breast height of trees with increasing altitude above sea level has increased.

According to the study quantitative and qualitative characteristics of grain sorghum (var.Spideh) performance, this seed was planted in research field of the Islamic Azad University Meybod branch in spring of 2009 in split plot design based on randomized complete blocks with three replication. Three planting dates (6.5, 6.20, 7.5) were selected as main plots and densities of 75, 100, 150 thousand plants per hectare were assigned sub-plots. In this test traits of yield, 1000 kernel weight, number of seed per panicle, number of panicles in square meter, harvest index and protein percentage of seed were evaluated. The results of these tests showed that the effect of different plant density on grain yield, 1000 kernel weight, harvest index and grain protein content had a significant difference, and with increased density, 1000 kernel weight, harvest index, number of seed per panicle and grain protein showed significantly reduced, but yield increases with increased density. The results showed that 5.7 date of planting was better than two other dates and superior yield rate of most 2.76 tons per hectare planting 7.5 was found between density. The density above the most suitable plant was 150 thousand hectares. It would be better to plant sorghum (Sapideh variety) in the range between 5th July and 23rd July in Meybod and similar area.

In order the examine the effect of muskmelon tolerance on some of herbicides, a field experiment was conducted in spring of 2009 in Saveh farmland, Iran. The Experiment was conducted by using a randomized complete block design with three replications and applying 13 treatments. The following herbicides were examined: sonalan, basagran, stomp, goal, basagran+gallant super, treflan, sonalan+gallant super, nicosulfuron+gallant super, eradicane, goal+gallant super, nicosulfuron, treflan+gallant super and gallantsuper. All herbicide treatments were applied at the rate of recommended. Herbicide injury score (0 to 100) were recorded at one & two weeks after application of herbicides.The results showed that the lowest injury occurred by treflan, sonalan & stomp with 4.1, 7.5 & 12.5 percent, respectively and maximum injury occured by goal, eradican, nicosulfuron & basagran. All plants were destroyed by eradiction treatment. Overall, three pre-planting herbicides (treflan, sonalan & stomp) are recommend for muskmelon cultivation.

In order to determine the effect of different amount of nitrogen application in different sowing dates on phenological traits, plant height and seed yield of canola (Brassica napus L.) Hyola 401 cultivar, the experiment was conducted as a randomized complete block design in a split-plot four times in Biekola Agriculture Research Station in Neka city during 2008-2009. Five sowing dates including 29 October, 8, 18, 28 November and 8 December were considered as main plots and four levels of nitrogen urea fertilizer application including 150, 200, 250 and 300 kg/ha urea were considered as sub plots. The results revealed the significance of sowing date and nitrogen for number of days to flowering, number of days to end of flowering, plant height, number of pods per main raceme, number of pods per plant, number of seeds per pod, 1000 seed weight and Seed yield Also the nitrogen effect was significant on each studied traits except duration of flowering. Interaction sowing date and nitrogen application were not significant for more studied traits exept number of pods per plant and 1000-seed weight. Among yield components, number of pods per main raceme and pods per plant had significant correlation with seed yield, indicating variations of these traits in different sowing dates, and also more effect of different nitrogen levels on seed yield. The significant positive correlation was observed between seed yield and each phenological trait, indicating the first and second sowing dates and also high amount of nitrogen levels made increasing amount of phenological traits and seed yield. In the first sowing date the seed yield related to four nitrogen application levels were 2864, 3026, 3276 and 3707 kg/ha respectively. For the fifth sowing date seed yield were 1754, 1835, 1973 and 2268 kg/ha respectively. Therefore one of the effective ways for compensating of decreasing yield components and seed yield due to late planting date is increasing the amount of nitrogen application.

Thin layer chromatography (TLC) method was used to determine the diversity of gamalinolenic (GLA) fatty acid in sixteen ecotypes of Iranian ox tongue flowers. In assessment firstly oil content of root, leaf and seed organs was extracted by soxhelt system and hexane solvent. Isolation. And identification of GLA were conducted via TLC on stationary phase of silicagel 60f 254 and the movable phase of (hexane, diethil ether – glacial acetic acid) by using phosphomolibdic acid reagent. The data obtained from TLC spots areas has been analysed by spss15.0 and clusters of GLA diversity traced. It was based on Squared Euclidean distance and Agglomerative Hierarchical algorithm. Within group average linkage was used for tracing dendrogram. Refrence line at eleventh value of genetic distance, clustered mentioned ecotypes in three main gorupes. The result of this project not only can be used in plant breeding programs for fatty acid improvment of Iranian oxtongue flower but olso can be used as a biochemical data in chimotaxonomy field for discrimination of intra and inter specific of Echium genius.