PLANT AND ECOSYSTEM
Year:2010 | Volume:5 | Issue:21|Papers Count:10

The genus Lallemantia Fisch et Mey belongs to Lamiaceae family is represented by the following 5 species: L. peltata, L. canescens, L. iberica, L. royleana and L. baldshuanica. In this study, in order to identify and distinct the species from each others, the morphological characters of Lallemantia species were investigated. Plant description is based on living and herbarium specimens.30 Qualitative and quantitative features were studied, and general explanations of qualitative attributes are based on Stern Terminology, and all measurements were made directly on herbarium specimens. Morphological characters such as: habit, stem length, width, length and shape of stem and floral leaves and its petioles, calyx and its teeth, bracts and inflorescent, the forms of leaf margine, apic and base, corolla colors and calyx corolla ratio were investigated. The present study showed that, some morphological characters were varying between species. Significant variations, mainly useful at the infrageneric level were found in: stem length, leaves shape and margins, the shape and size of upper tooth of calyx, bracts and inflorescent shape and corolla calyx ratio. These features had taxonomic value in the classification and were useful in identification of species, specially 2 longitudinal folds whitin the upper lip of corolla were useful in distinguishing of Lallemantia species from other genera in Lamiaceae family.

Damavand is one of the important agricultural areas in Iran, especially in raising and Solanum L. , Cucurbita L. , Cucumis L. and also crops such as Malus Mill. , Juglans L. and Cerasus Miller. In this research, about 114 species of the weed in the area were determined. The majority of the weeds, among the 29 families, belonged to Asteraceae and Poaceae and most of their species were found in wheat farms. In this research, the species of the weeds and their relative importance value were distinguished in each farm, too.

Fenugreek (Trigonella foenum graceum L. ) is an annual plant belonging to Legominosae family with a long history of farming in Iran. There are various populations of this plant in Iran. However, no comprehensive study for fully understanding of it has been yet carried out. Twenty Iranian native populations of fenugreek were collected from different parts of the country to asses the genetic variability, including their cytogenetic characteristics. The analysis of poloidy level revealed that all the populations were diploid (2n=2x=16). Chromosomal characteristics including Length of each chromosome, sum of the length of all chromosmes and relation to sum of each chromosome were measured. Genotype of Ardestan had largest chromosomes (7 m) and the shortest one (2.45 m) belonged to genotype of Borazjan. Cluster analysis categorized the genotypes to seven groups. Based on the results the native Iranian populations of Fenugreek showed high diversity regarding the features under study and they may provide suitable genetic resources for breeding programs.

The effect of drought stress on growth indices of Balm (Melissa officinalis L.) was conducted in Alborz Research Station-Karaj Iran. This research was performed under a Completely Randomized Block Design with 4 replications in 2006. In this research the effect of stress treatments T1 (control=100%FC), T2 (80%FC), T3 (60%FC), T4 (40%FC) and T5 (20%FC) were studied on some growth indices of Balm such as LAI, TDW, CGR, and RGR according to the Growing Degree days. Results showed that the maximum LAI and TDW were 2.5 and 650 gr/m2 in control (100%FC) treatment respectively. So minimum LAI and TDW related to hard stress treatment (20%FC). The control treatment had high CGR in the first and end of growth periods but RGR was low in the late in this treatment. The maximum RGR were observed in medium stress and specially 60%FC. It had distinguished that the best indices were belonged to non stress condition. But, attention to closely of 60%FC indices to control and highest percentage and yield of essential oil of this treatment was accepted as a suitable drought stress in production of this plant.

This experiment was conducted to evaluate the effect of drough stress on proline accumulation and memberane stability of four wheat s variety: shiraz – chamran –pishtaz and Niknejad both in farm and laboratory of the Islamic Azad University of shahr-e-Qods. Exprimental design was split plot in complete randomzed completely block with 4 replications. In this research physiological traits as proline and memberane stability were measured according to two levels of irrigation (normal level and 30% fc), Rootlet length was also measured under different osmotic potentials. The results showed that there was a significant difference between varieties for rootlet length, and variety of pishtaz had more rootlet length than others (47.76mm). The result of field experimental showed that the effect of drought stress on leaf and membrane stability. And seed yield was significant and treatments under normal irrigation w ith means of 4374.8 kgha-1 had more seed yield than droght stress. The results indicated than seed yield of Niknejad and chamran variety were more than others.

In order to study the effect of super absorbent polymer on some agronomic characters (yield, seed 100 weight and Harvest index) and phyisiological characters (EC, RWC) in red bean (phaseolus vulgaris) varieties under drought stress, various tests conducted in laboratory and greenhouse experiments in research station of the Islamic Azad University, Karaj Branch in 2005. In greenhouse experiment factorial design under randomized complete block design (RCBD) with four replications were used, varieties were factor A (Derakhshan, D81083, Naz) and time of irrigation was factor B and C with superabsorbent concentration (0, %5, %7). Irrigation treatment was on main plot, and factor B, C were on sub plot. The results showed significant difference between irrigation treatments, varieties and polymers concentration for measured characteristics. Drought stress caused significant effects on increasing EC and reduced seed yield, seed 100 weight and Harvest index. super absorbent polymer (7%) increased the agronomic characteristics. Naz and Derakhshan varieties were drought tolerant and sensitive varieties respectively. The results showed that super absorbent, absorb and keep the water around the roots and it can reduce death of plants from water shortage. These compounds can increase agronomic characteristics, so with attention to increasing yield and yield components and reducing the use of water, application of superabsorbent was proposed specially in water deficit condition.

Determination of range suitability for different purpose is essential for sustainable development. In this study to determine the part of rangeland suitability for Apiculture, Three sub-models including physical and environmental factors, vegetative covering, recovering pests and enemies, were made for final model. The study was conducted according to F. A. O (1991) method, In Asal Asal, Arou, Namak koosar rangeland of Lar watershed. According to results of sub-models 40/05% of area was high suitable (S1), 9/08% was moderately suitable (S2) and 37/74% was poor suitable for Apiculture. The most important limiting factors for suitability were temperature, range degradation. The effective factors to suitability were the desirable plants for bees and water source distribution, roads, and the lack of enemies and pests.

To study the competitive effects of redroot pigweed (Amaranthus retroflexus) and lambsquarter (Chenopodium album) on potato growth indices, an additive experiment was conducted in the spring of 2004 and 2005 in split-split plot based on randomized complete block design with 4 replications at the Seed Potato Production Station of RAN in Firouzkooh. Treatments were included 2 weed species in main plots (Amaranthus retroflexus and Chenopodium album), weed density in sub plots (2, 4 and 8 plants per meter of row) and relative time of weed emergence in sub-sub plots (8 and 4 days prior to potato and the same time with potato emergence in 2004 and the same time with potato, 2 and 4 weeks after potato in 2005). Results showed that both weed species reduced height, LAI, CGR and RGR. Redroot pigweed caused more reduction in potato growth indices than lambsquarter.

In order to survey the effects of biofertilizers on the quantitative and qualitative features of three cultivars of oil-sunflower (Helianthus annus) this study was carried out during the years of 2007-2008 in "Khoy". The experiment was done in factorial test based on complete randomized blocks design in four replications. the cultivars of sunflower as the first factor in 3 levels included Hisun 33, Alstar and Euroflor; and the secondary factor included compound of seeds inoculation with biofertilizers and chemical fertilizers in 8 levels included 50% K2SO4+Biosulfur, 100% K2SO4+Biosulfur, 100% K2SO4, 50%Urea+ Azotobacter, 50% Urea+Nitroxin, 50% Urea+Azotobacter+Nitroxin, 100% Urea, 100% Urea+100% K2SO4. The results of the experiment showed that the effect of cultivar and fertilizer was significant on plant height, grain yield and oil yield. The interaction effect also was significant on plant height and oil yield. The comparison between the averages of cultivars showed that Hisun 33, concerning with the qualities studied, were better than other two cultivars. So that Hisun 33 produced diameter of tray 18.8 cm, the maximum grain yield and oil yield respectively with 3832 and 1705 Kg per hectare. Among different levels of fertilizers of seeds inoculation with Biosulfur+100% K2SO4 and 50% Urea+Azotobacter +Nitroxin had the outmost positive effect on the increasing of, grain yield and oil yield. Ultimately, the total results of two year research seeds inoculation of sunflower with biofertilizers accompanied by decreased use of chemical fertilizers, like nitrogen fertilizers can have benefit on the improving features of quantitative and qualitative oil – cultivars.