محمدرضا چایی چی

To investigate the effect of biological fertilizers and vermicompost, on vetch and coriander in different intercropping mixtures (medicinal forage), an experiment was conducted in split plot based on RCBD design with 3 replications. The experiment was conducted in Research Farm of College of Agriculture, University of Tehran in Karaj, Iran during growing season of 1389-1390   The main factor comprised of 4 levels of fertilizer application viz. control (no fertilizer application), vermicompost, biological fertilizer and biological fertilizer + 50% vermicompost.  The sub plots were allocated to 7 levels of different mixtures of intercropping of vetch and coriander including: sole cropping of vetch (weed infested) (Vw), sole cropping of vetch (weed free) (V0), sole cropping of coriander (weed infested) (Cw), sole cropping of coriander (weed free) (C0), intercropping of vetch + 50% coriander (VC50), intercropping of vetch + 75% coriander (VC75), and intercropping of vetch + 100% coriander (VC100).  The measured parameters  was weed biomass.  The results indicated that vemicompost across all levels of intercropping had significant effect on decrease weed biomass.  Also the lowest weed biomass was achieved in (VC75) and (VC100) intercroppings.  According to the results of this experiment, to decrease the consumption in herbicides and increase the level of health application of intercropping and natural fertilizers could be recommended.

Salinity is one of the most important factor that prevents plant growth and physiological development. To study the soil application of zeolite on alleviating the adverse effects of salinity on milk thistle, this research experiment was conducted in research greenhouse of College of Agriculture, University of Tehran, Karaj in 2016. The experimental treatments were arranged as factorial based on randomized complete block design with three replications. The first treatment was salinity levels of irrigation water including of control (as check), 4, 8, and 12 dS/m, and the second treatment comprised of different levels of zeolite application in soil (control, 0.01, 0.05 and 0.1%). The result indicated that salinity had adversely effect on the vegetative and physiological characteristics of milk thistle. Application of zeolite at 0.05 % in salinity levels of control, 4 and 8 dS/m increased the plant total biomass by 38, 43, and 41%, respectively. Application of zeolite at 0.05 and 0.01% increased the potassium and decreased sodium content in the root. Also the lowest Na+/K+ ratio (1.65) was achieved at severe salinity level (8 dS/m) while zeolite was applied at 0.05% level. As the salinity increased, the antioxidant activity in the plant was also increased. Result of this experiment showed that application of zeolite could be considered as a solution to modify the adverse effect of salinity in milk thistle.

To evaluate the population and diversity of weeds in wheat fields in Qazvin, Iran, an experiment was conducted during 2015-2016 growing season. A net sampling method was employed to take samples from 9 fields of 3-hectar area which were managed either in dry farming, no-tillage, or irrigated systems. Samples were taken at two growing stages when wheat plants were at tillering and when they reached full stem growth stage. The highest population and diversity of weeds was observed in dry farming system and the lowest was seen in irrigated system. The frequency of weed population was lowest in no-till system. The highest grain yield (6231 kg/ha) and total dry matter (18580 kg/ha) was measured in irrigated system, and the lowest grain yield (2078 kg/ha) and total dry matter (60180 kg/ha) was obtained in dry farming system, respectively. Based on the low weed population and a grain yield of 5830 kg/ha in no-till system, it seems that this production system is economically and environmentally justifiable for wheat production in Qazvin Provence, Iran.

This research project was conducted to study the population and biodiversity indices of weed species in wheat fields in Qazvin province/Iran during the 2015/2016 cropping season. A networking sampling method was employed to study the weed species in three wheat production systems of no-tillage-rainfed (low input), no-tillage-irrigated (intermediate input), and moldboard-tillage (high input)-irrigated systems. Sampling was conducted at two growing stages (Tillering and end of stemming). The species diversity of Simpson, Shannon-Weiner, Margalof richness, Menhinic and dominance index were determined by genus and species. The dominance index in dry farming fields (0.9245) was higher than irrigated farms, and in irrigated farms with moldboard tillage (0.7451) was higher than no-tillage irrigated fields (0.6664). The Shannon index in low input farms (2.9693) was more than high input (1.5230) treatment and in high input farms was more than intermediate input (1.4346) treatment. The highest Margalof richness index was obtained from dry farming system (1.8516) while the lowest was observed in no-till fields (0.7432). The species richness index in low input farms was more than high input and in high input was more than intermediate input (with conservative tillage) fields. The results of this project demonstrated that no-till production system is associated with less weed species and diversity in wheat fields.

Salinity stress is one of the most limiting factors in plant growth and physiological activities. To extend crop production in saline regions, application of plant promoting growth substances like Chitosan is necessary to modify the adverse effects of salinity. Milk thistle is an agro-medical plant that is familiar as a weed. However, Silymarin (which is produced by Milk thistle as a secondary metabolite) is one the most important material for treating such disease as; liver diseases, blood fat, diabetes, hepatitis, and cancer. Application of bio stimulants is one of the solutions for decreasing adverse effects of abiotic and biotic stresses on plants and increasing quality and quantity of plant yield production, so chitosan is a compound that induces defense mechanisms against stresses.
This experiment was conducted to evaluate the soil application of chitosan on vegetative, generative and physiological activities of Milk thistle in 2016. The experiment was conducted in Research Greenhouse of College of Agriculture the University of Tehran, Karaj, Iran. The experimental treatments were arranged as factorial based on a randomized complete block design (RCBD) with three replications. The first factor comprised of four saline irrigation water levels of control (Urban water with 1.2 dS m-1), 4, 8 and 12 dS m-1 and the second factor was application of different levels of Chitosan consisting of control (without chitosan application), 0.01, 0.05, and 0.1 percent of chitosan based on 1-kilogram dry soil weight in Rhizobags. Chitosan with high molecular weight was purchased from Sigma Aldrich. 12 seeds of Milk thistle were sown in each plastic pot (23×24 cm diameter and height) containing 8.0 kg of soil, at the depth of 2 cm. After 72 days planting, plants with a uniform growth were selected for experiments. At least three plants were randomly selected from each treatment. The plant root and shoot were cut at the base and weighed to determine the dry root and shoot weight. Samples were dried at 60οC for 48 hours, and their mean root and shoot dry weight were recorded for each treatment at each replicate. Also, Statistical calculations were done by SAS software, 9.1 version, and means were compared by Duncan multiple test with 5% probability.
The result showed salinity stress had significant effect on all of the growth, physiologic and ionic trait (p≤0.01). Mean comparisons in chitosan levels showed the maximum total biomass, leaf area meter, relative water content and membrane stability index were achieved with application of 0.05% nano chitosan. In 4 dS m-1 saline water, the highest total dry mass was obtained at 0.01% of chitosan by increasing of 21.6% compared to control (p≤0.01). In all of the salinity levels, chitosan application increased the leaf area index in compared to control (without chitosan application). The maximum leaf area index (4.264) was achieved in 0.05% chitosan concentration under non saline condition. Under 12 dS m-1 salinity, application 0.05% chitosan concentration decreased by 10.4% and 16.5% in sodium content and sodium potassium ration in shoot, respectively. The mechanism of action of chitosan on growth is not clear. It was also found that chitosan may induce a signal to synthesize plant hormones such as gibberellins and enhance growth and development by some signaling pathway related to auxin biosynthesis. Chitosan stimulates vital processes of plants on every level of biological organization, from single cells and tissues, through physiological and biochemical processes, to changes on the molecular level related to the expression of genes. The result of the experiment demonstrated the adverse effect of salinity on growth, physiological activity, and nutrient content in Milk thistle. Application of chitosan at 0.05% (v/v) in soil could modify the adverse effect of salinity on total biomass, leaf area index, relative water content, and membrane stability index; however, 0.01% chitosan concentration was more effective on photosystem II efficiency.
Based on the result of this experiment, salinity stress has negative effects on growth, physiology and mineral element contents of Milk thistle. Application of 0.01% of chitosan could modify the adverse effects of irrigation water salinity on Milk thistle. Generally, application of chitosan could decrease Na effects in the Milk thistle, so the rate of Na in the shoot and root was decreased under high levels of salinity. The present study demonstrated that chitosan can be used as an ecofriendly compound to protect milk thistle plants as well as to enhance growth and biochemical parameters under saline water.

The AquaCrop model has been used for optimum sowing date determination for maximum yield production based on historical climate data in Moghan plain, Ardabil province, Iran. Based on phonological data for the eight main cultivated crop gathering from Moghan plain and thirty years climate data, the optimum sowing dates were determined after model calibration. The model used cumulative growing degree days, effective and active base temperature and calculated harvest index to perform each crop yield. Determination coefficient, normalized root mean squared and index of agreement were 0.99, 29.16 and 0.97 respectively. The statistics showed that the model could accurately perform the crop yield estimation in this region. Based on the results the simulated sowing window for winter wheat was a little bit shorter. The winter barley also performed as winter wheat. The spring maize simulated sowing window was longer than usual period. But the simulated sowing window for winter canola, cotton, soybean and maize was the same as actual sowing window. The net Irrigation requirement in the determined planting dates have been calculated by the AquaCrop and compared with the NETWAT software outputs. In this Comparison, determination coefficient, normalized root mean squared and index of agreement were 0.92, 14.07 and 0.99 respectively. The results showed the importance of using winter precipitation in crop production in the region and lower water irrigating input using winter cultivation should be noted.

The widespread use of chemical fertilizers and their effects on agricultural products is an issue that is still being studied and discussed. An important subject for study is the replacing of biofertilizers and organic fertilizers with chemical fertilizers and the application of integrated fertilizers to increase soil fertility in sustainable agriculture and for livestock (Wu, et al., 2005). Integrated fertilizing systems are more reliable than conventional fertilizers in producing better quality and higher quantities of whole forage in arid environments with water stress or a water deficit irrigation system. (Jahanian, 2012). On the other hand, drought stress is the most important abiotic factor that limits growth and development of plants in arid and semi-arid areas. Water stress conditions can also effect the root’s ability to uptake nutrients and leads to decreased forage quality. Evaluating new methods of irrigation and deficit irrigation systems can reduce the adverse effect of drought stress (Keshavarz Afshar et al. 2012). Therefore, the study of different fertilizing systems along with irrigation regimes is the main goal of this research in order to improve forage quality and trigonelline content in fenugreek plants.
A field experiment using a split plot on a RCB design with three replications was conducted at the Research Farm of the College of Agriculture, University of Tehran, in Karaj, Iran during the 2012 growing season. Treatments consisted of three levels of irrigation protocols assigned to the main plots as follows: complete irrigation (providing 100%), moderate drought stress (providing 75%) and severe drought stress (providing 50% of weekly evaporation). Six levels of fertilizing systems assigned to the subplots consisted of: a control, chemical fertilizer, biological fertilizer (seeds inoculated by Pseudomonas and Azotobacter), and three different integrated fertilizers: bio흍% chemical, bio% chemical and bio% chemical
By increasing the drought severity, the percentage of CP, WSC, NDF, ADF, ash and trigonelline concentrations increased while the percentage of DDM, mineral contents and trigonelline yield followed a decreasing trend. By increasing NDF and ADF, forage quality was reduced. This reduction also came with a decrease in DDM. Drought stress caused an increase in the trigonelline, while most of the growth parameters in the fenugreek plant decreased. The highest values for DDM, mineral contents and trigonelline yield were achieved with full irrigation treatment accompanied by integrated fertilizer (Bio75% and Bio50%). The highest percent of CP, WSC and trigonelline was measured in severe drought stress together with Bio100%.
The results of this experiment indicated that the integrated fertilizers were more efficient than bio- and chemical fertilizers. They could mitigate the adverse effect of drought stress and produced the highest forage quality and secondary metabolite. These characters along with less use of chemical fertilizers produced the highest yield in quality and quantity compared to the other fertilization systems. Under the conditions in Karaj, it seems that application of integrated fertilizers along with moderate deficit irrigation (providing 75% of weekly evaporation), due to less water consumption and less negative effect on yield and forage quality, can be suggested for a sustainable agricultural system in arid and semi-arid areas like Karaj, Iran. Fenugreek, due to its dual positive characteristics, can be suggested as a medicinal-forage crop for livestock

Intercropping has many advantages including improved soil conditions (Chen et al., 2004), increased resources and better weed control (Banik et al., 2006). Due to their positive effect on forage quality, intercropping of cultures has an important role in farming systems. Furthermore, intercropping improves absorption of solar radiation, increases the activity of soil microorganisms and contributes to better weed- and pest-resistant conditions (Karadage, 2004). The goal of this research is to investigate intercropping of maize and sorghum with legumes, such as mung beans, cowpeas and clover, in order to evaluate the benefits. The benefits should include increased yield, improved quality forage (higher protein levels), and better weed control. Intercropping should best suit the climatic conditions of the region and improve agricultural practices.
In order to investigate the effect of additive intercropping of maize and sorghum with legumes on qualitative and quantitative forage and weed growth, a field experiment was carried out over two years, in the 2011-12 growing seasons in the village of Mafin-Abad, in the Eslamshahr region of Tehran Province. Maize and sorghum monoculture and their intercropping with three different legumes (mung beans, cowpeas and berseem clover) in different additive intercropping systems were compared in a randomized complete block design (RCBD) with three replications. The traits evaluated in this study include yield, forage dry matter, protein, index against ground, and economic advantages.
The results showed that intercropping increased forage dry matter and crude protein. Intercropping also significantly decreased weed dry weight. In all intercropping treatments, LER was above 1, indicating yield advantages for intercropping. Maize and cowpeas in the 100% density treatment showed the best results over both years and produced the highest dry forage yield, LER and CP and the least amount of weed dry weight. Based on the results of this experiment, it could be concluded that maize and sorghum-legume intercropping could substantially increase forage quality and quantity. These intercrops can be recommended to replace monoculture systems. Maize and sorghum-cowpea additive intercropping could be highly recommended because of higher forage quality and quantity with fewer side effects on the environment.
The results showed that intercropping could be used to increase yield, improve forage quality and weed control. Intercropping cultures also indicated that LER was more than 1 and led to a higher economic profit in comparison with a monoculture. This can be a suggestion for farmers to use intercropping in this recommended form. In the intercropping of maize and sorghum and cowpea, particularly with a density of 100%, cowpea clearly manifests itself. Therefore, intercropping can be recommended to farmers as a way to boost performance, revenue, forage quality (protein) and control weeds.

Seed enhancement methods are applied to eliminate or decrease adverse environmental stress effects and increase seed germination rate and vigor of rangeland plants. The coated seed process is from amplifier ways that stick various materials on the outer surface of the seeds that minimize the negative environmental effects and increase the ability of plant establishment. The aim of this study was to assess the effects of seed coating methods on germination of Triticum aesativum, cultivar Sardariin different moisture stress levels and sowing depths. This experiment was conducted with a completely randomized design with four replications. Treatments of covering material was used in four levels including, non coating levels (NC), mineral-based coating (CC), organic- based coating (OC), and hydro gel-based coating (HC). Moisture treatments were used in three levels of moisture soil content. Two planting depth and three seed diameter including M9%, M14% and M21% were used. During the test, speed of germination was evaluated. The results showed that moisture treatments and planting depth at had highly significant effect and there was no significant effect of coating treatments. Also the interaction between type of covering material and soil moisture was not significant for germination speed, but there was significant difference between treatments of seed size in M9% and M21%. Although in the triple interaction, increasing moisture and planting depth enhanced the speed of germination process, but it was not significant statistically. The seedling growth of covered seed developed significantly, so it can be useful in enhancing plant performance.

Water scarcity adversely affects many physiological and metabolic processes of the plants. To study the effects of drought stress and fertilization on some physiological characteristics, essential oil percentage and yield of spearmint, a field experiment was conducted at the Research Farm of the College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran. The experiment was conducted in a split plot arrangement based on a randomized complete block design with three replications. Treatments included three irrigation treatments (100%, 75% and 50% of plant water requirement) as the main plot and four fertilizer regimes including no fertilizer (control), chemical fertilizer (N), bio-fertilizer (rhizome inoculation with Azotobacter, Pseudomonas and mycorrhiza) and integration of biological fertilizer and 50% chemical fertilizer as the sub-plot. The results showed that all traits measured were significantly affected by the main and interaction effects of deficit irrigation and fertilizer. The content of chlorophyll a, chlorophyll b, carotenoids, total chlorophyll, percentage and yield of essential oil and yield decreased with increasing water stress while the rate of carbohydrate and proline as well as the electrolyte leakage percentage increased. Furthermore, the results showed that under 100% and 75% irrigation systems, application of chemical and integrated fertilizers improved the physiological characteristics, yield and percentage and yield of essential oil. Under 50% irrigation regime, the best performance was related to bio fertilizer.

To study the effects of mycorrhiza fungi and humic substances on yield and yield components of corn (Zea mays L. var. s.c. 704) under limited irrigation condition, an experiment was conducted in split plot arrangement based on RCBD in four replications at the research farm of University of Tehran (Karaj-Iran) in 2011. The main factor consisted of three irrigation levels i.e. normal (irrigation every 7days); mild water stress (irrigation every 10days) and severs water stress (irrigation every 14days). Fertilizer treatments comprised of zero (control); application of phosphorus 50% (based on soil testing result); application of phosphorus 100%; phosphorus 50% plus mycorrhiza; phosphorus 50% plus humic substance; and phosphorus 50% with humic substance plus mycorrhiza. The results showed that water stress significantly decreased yield. The fertilizer treatments had significant effects on grain yield, biological yield, and plant height, grain protein, grain nitrogen and phosphorus; but had no significant effect on seed weight, and harvest index. Comparison of treatment means for different traits showed that the greatest change compared to the control, was for the treatment of 50% humic compounds plus phosphorus fertilizer with mycorrhizal fungi.

There is a very close relationship among the various active elements within rangelands, which affect their sustainability and productivity. The chemical characteristics of the soil are among the most important factors in fertility and, consequently, in the density and type of plant cover of rangelands. Livestock grazing impacts on some qualitative soil properties, such as its physical and chemical and biological characteristics and including more reactive parameters such as biological activity, organic matter, bulk density, concentration of nutrients, etc. These have been reported for different time periods in rangeland ecosystems. The objective of this research was to investigate changes in chemical characteristics (EC, pH, available form of phosphorus and potassium, calcium carbonate, moisture content, etc.) and plant cover in three areas under treatments of heavy grazing (critical area), normal grazing (key area) and excluded from grazing (reference area).
This study was conducted in Makhmalkoh region located in north of Khormabad City and using soil samples from 0-15 and 15-30 cm depth from the three selected areas (reference, key and critical) with different grazing intensities. Soil samples were collected five times over 2 years and at four-month intervals from five one-hectare paddocks in each area. Soil EC, pH in saturated extract and OM, total nitrogen and available P and K were all determined using standard methods and the changes over time were compared. Plant cover density in each area was investigated using the plate method, and at three times, by determining the percentage of plant crown covers for each growth form and the percentage of bare soil and litter in each plate. The experiment was conducted based on a factorial completely randomized design.
The results showed that the effects of area (grazing intensity) and time of sampling (seasonal variation) were significant for total N, OM, and available P and K P Differences in grazing intensity affect the percentage of plant cover and plant species in a rangeland. The highest plant cover was observed in the key area and the least in the critical area. Inside the key area, shrubs were not observed. Also, a decrease in the plant cover percentage of grasses and an increase in shrubs were observed with an increase in grazing pressure. Decrease in soil OM and moisture content along with concentration of available P and K in soils of the studied area were observed due to grazing, which reduced soil fertility. Changes were more obvious for the 0-15 cm soil depth due to addition of animal manure, plant residue on the surface soil and more roots. A reduction of more than 10 percent in plant cover and an organic matter reduction due to intensive grazing can cause severe erosion and growth of unfavorable plants, which requires suitable management practices of livestock grazing and plant cover.

Seed dormancy is a defensive system against unfavorable environmental conditions. This research was designed to evaluate the drought stress effects on seed germination and dormancy of Hordeum spontaneum genotypes. Therefore, 19 genotypes of the species and the Nosrat (cultivated barley) cultivar were evaluated under normal water condition and drought stress in a green house study. Complete randomized block design with three replications were used in this study and two stress levels including 95-100%FC and 25-30% FC, were imposed to the plants. Based on results, drought stress had significant effects on germination index, germination percentage, seed dormancy, germination value and germination energy. Drought stress increased the seed dormancy in most of Hordeum spontaneum genotypes. Principle components analysis of the traits in both water conditions showed that, stress tolerance index and length of coleoptiles are positively related, which indicates that genotypes with longer coleoptiles are more tolerant to drought stress conditions, and it seems that, this trait has evolved to increase the adaptation to drier climates.

In ley-farming variation system hard-seed is the major ecological trait of annual medic to guaranty the soil seed bank reserve. The trend of hard-seed breakdown is affected by environmental and managerial factors. In order to study, the effect of different nutritional systems, post harvest period and harvest management on hard seed breakdown trend in the annual medic, this experiment was conducted by split plots in time based on complete randomized block design with three replications in two locations (Sararoud dry Agricultural Research Institute and Mahidasht Agricultural Research Stations, Kermanshah) in dry farming system during 2008 and 2009 growing seasons. The results indicated that the highest hard-seed breakdown was periphery 13% in the Sararoud Research Station. After 8 months of post harvest period the mean of hard-seed breakdown reached to 14% in two locations. Also in harvest and non-harvest treatments forage the average hard-seed breakdown were 12.2 and 12.7 percents, respectively.

In order to investigate the effect of different levels of biofertilizer inoculation and phosphorus chemical fertilizer on mineral elements absorption in forage corn SC. 540 under humidity regimes، an experiment was conducted as Line source based on a randomized completele block design with three replications during two growing seasons of 2012 and 2013. The implementation of Line source was applied four levels of irrigation (not stress، mild stress، moderate stress، severe stress). Five phosphorus levels included the application of 100 percent triple super phosphate fertilizer and without biofertilizer، 75 percent recommended chemical fertilizer with biofertilizer، 50 percent recommended chemical fertilizer with biofertilizer، 25 percent recommended chemical fertilizer with biofertilizer، biofertilizer and without chemical fertilizer، too. The results of experiment showed significant differences of fertilizer treatment in most of studied traits in the first and second of year. The highest of fresh and dry forage yield obtained to apply treatment of 100 percent triple super phosphate fertilizer and without biofertilizer that this value wasn’t statistically significant difference with 75 percent recommended chemical fertilizer and biofertilizer. The mineral elements absorption decreased with increasing of stress condition. The highest amount of absorption of phosphors recorded in 75 percent recommended chemical fertilizer with biofertilizer، although in stress condition، the highest amount of absorption of phosphor recorded in 50 percent recommended chemical fertilizer with biofertilizer.

To study the effect of different fertilizing systems on yield and quality characteristics of fennel Biomass, an experimental was conducted at College of Agriculture, Shahed University in 2011. The experimental design was split plot on the basis of randomized complete block design with three replications. The main factor comprised of levels of fertilizer application viz. control (no fertilizer application), Bio-fertilizer (Azospirillum/Azotobacter, biophospherous fertilizer), 3. Integrated fertilizer (bio fertilizers+ 50% chemical fertilizer), and 4. Chemical fertilizer (triple super phosphate based on the soil analysis). The sub plots allocated to levels of number of cuttings (harvests) consisted of first, second, third and fourth cuttings. Results showed that the effect of fertilizer, cutting and interaction between them on measured traits was significant. The maximum fennel height, branch number per plant, dry weight and essential oil yield was obtained by applying integrated fertilizer in the first cutting. Maximum leaf/stem ratio was obtained from control treatment in the fourth cutting. The highest percentage of essential oil was obtained by applying integrated fertilizer in second cutting. According to the results, the use of integrated fertilizers can provide the highest quality food that reflects the desired effect of positive integrated fertilizer in production of medicinal forage of the environmental aspects.

Breaking seed dormancy is an essential step towards germination improvement in Hordeum vulgare ssp. spontaneum. This study was conducted to evaluate the effects of physical, chemical, hormonal and stratification treatments on Hordeum spontaneum seed dormancy. In the current research two highly dormant genotypes of Hordeum spontaneum (TN1350 and TN951) were evaluated. To this purpose, 25 seeds in four replications were placed in 9 cm petri dishes containing filter paper saturated with distilled water (control), chemical or hormonal solutions. To induce the stratification treatments, seeds were kept in 35˚C (heat stratification) or 5˚C (cold stratification) for periods of 2, 4, 6 and 8 weeks. Results indicated that heat stratification increased germination significantly. Germination percentage of seeds under 35˚C treatments increased since the second week of treating and reached the maximum in the fourth week (47.5% in TN951 and 86.25% in TN1350). Results showed that GA3 in all used concentrations was the most effective hormone in inducing germination compaired to other used hormons in this study. The highest germination percentage in Hordeum spontaneum seeds was observed in 100 mg/l GA with increased germination percentage up to 68.75% in TN1350 and 31.25 in TN951. Results of this study revealed that seed dormancy in Hordeum spontaneum can be overcomed by GA3, and heat stratification. On the other hand, seed dormancy was apparently deeper in the genotype with darker seeds)TN951(which were also less affected by after ripening treatments.

Vegetation cover of Rangelands with have effective role in water reserve and soil conservation. Grazing by domesticated animals in rangelands protect desirable and palatable species and sustainable production in rangeland ecosystem. In order to investigation grazing effects on soil infiltrations and physical-chemical properties an experiment was conducted at three regions, consisted of reference, key and critical areas for this reason, rangelands part of Vaz watershed in Mazandaran province Iran. After field survey, three areas with different grazing intensity were determined and after study of vegetation cover, the experiment of water infiltration in soil carried out using of double ring method with suitable replications and then sampling of soil was done for measurement of some physical and chemical characteristics. For infiltration an infiltration apparatus based on kastiakov equation were used to determinacy cumulative infiltration and temporal mean, rate and time of final infiltrations. Finally, Results of three areas were compared together. Results of ANOVA showed that the amount of the mentioned traits were highest, lowest and intermediate at closed, critical and key areas, respectively. Results of soil factors also indicated that interaction effect between treatment and year had significant effect on bulk density (p≤ 0.01) and Ca and P (p≤ 0.05).

Growing drought tolerant crops such as pearl millet can save water where irrigation water supply is limited. The objective of this project was to evaluate the pearl millet (Pennesitum americanum) forage yield under different irrigation regimes and nitrogen fertilizer rates. The field experiment was designed as a split factorial arrangement in randomized complete block design with four replications at the Research Field of University of Tehran, Karaj, in 2007. The combination of Irrigation regimes (40, 60, 80 and 100 % maximum allowable depletion of available soil water) and nitrogen fertilizer rates (0, 75, 150 and 225 kg N ha-1) were allocated to the main plots and harvest was assigned to the sub plots. It was observed that 40 and 60% maximum allowable depletion of available soil water produced the highest dry matter yield over three harvests (21.45 and 20 t ha-1, respectively). As water depletion increased to 100% maximum allowable depletion of available soil water and getting close to the third harvest, the leaf and total dry matter yield followed a decreasing trend. At 40% maximum allowable depletion of available soil water treatment, the highest total dry matter was produced on first harvest. The interaction effect of harvest×nitrogen was highly significant on total dry matter yield. The highest yield was produced on second harvest at 225 and 150 kg N ha-1. The lowest dry matter was produced in control treatment over all harvests. Therefore, by 60% depletion of maximum allowable depletion of available soil water and consuming 150 kg N ha-1, acceptable dry matter yield could be produced.

Wild barley (Hordeum spontaneum) is a valuable source of genetic diversity for adaptation to biotic and abiotic stresses which can be used for transferation of new genes to cultivated barley. To evaluate wild barley ecotypes for drought adaptation، nineteen ecotypes and a barley cultivar (Nosrat) were evaluated in experimental field of Seed and Plant Improvement Institute in Karaj. The experiment was carried out in a randomized complete block design with three replications in non-stressed and water deficit stress conditions. Agronomical، phenological and morphological traits were measured in ecotypes. Results indicated that phonological traits such as days to spike emergence، days to flowering and days to maturity were decreased under water deficit stress condition. Agronomic traits including spike length، plant height and biological yield were also significantly decreased. Under normal condition، grain yield، biological yield and harvest index showed a significant correlation with stress tolerance index (STI). Principle component analysis in normal condition indicated that even in non-stresses condition، agronomic traits had correlation with stress tolerance. Cluster analysis grouped the ecotypes in three different clusters including susceptible، semi-tolerant and tolerant ecotypes. Based on the results، ecotypes no. 7، 8 and Nosrat cultivar had the highest yield components and stress tolerance index، however relative water loss (RWL) and days to maturity (DM) were less in these ecotypes (164 days and 74. 27%، respectively). The results of stepwise regression analysis indicated that the relative water loss is a physiological trait which shows a close relation with stress tolerance potential of the ecotypes and is an important factor for adaptations to water deficit conditions.

To investigate the effects of different levels of biofertilizer and phosphorus chemical fertilizer on quantitative and qualitative yield of forage corn cv. SC 540 under different humidity regimes, an experiment was conducted as Line Source based on randomized complete block design with three replications in Agricultural Education Center of Shahid Naseri in Karaj during 2012 and 2013. The implementation of Line Source was applied as four levels of irrigation (non stress, mild stress, moderate stress and severe stress). Phosphorus factor was in five levels including the application of 100% triple super phosphate fertilizer without biofertilizer, 75% recommended rate of chemical fertilizer with biofertilizer, 50% recommended chemical fertilizer with biofertilizer, 25% recommended chemical fertilizer with biofertilizer, biofertilizer and without chemical fertilizer. The results of experiment showed significant differences among the fertilizer treatments for most of studied traits in the first and second years. The highest fresh and dry forage yield were obtained from the treatment of 100% triple super phosphate fertilizer without biofertilizer that was not significally different from the treatment of 75% recommended chemical fertilizer and biofertilizer. Moisture stress reduced forage yield up to 21.22, 12.07 and 2.78 percent in severe, mild and very mild stress conditions in 2012, respectively. Treatment of 75% recommended chemical fertilizer and biofertilizer had also the highest effect on forage quality parameters. The findings of this research indicated that growth promoting bacteria exist in biofertilizer, in addition to growth increasemend and reduction of fertilizer consumption, lead to increase plant tolerance under water deficit stress conditions.

To investigate integrated effect of biofertilizer and chemical fertilizer to tolerance forage corn (Single Cross Hybrid 540) under drought stress, an experiment was conducted as line source based on completely randomized block design with three replications in Agricultural Education Center of Shahid Naseri, Karaj, during 2012 - 2013. The implementation of line source was applied four levels of irrigation (not stress, mild stress, moderate stress, severe stress). Phosphorus factor was used in five levels including the application of 100% triple super phosphate fertilizer without biofertilizer, 75% recommended chemical fertilizer + biofertilizer, 50% recommended chemical fertilizer + biofertilizer, 25% recommended chemical fertilizer + biofertilizer, biofertilizer without chemical fertilizer. Results of experiment showed that GMP, MP, Harm and STI had positive and significant correlations with grain yield in both stress and non stress conditions in two years. The results of principal components analysis showed that two principal components approximately explained 100% of the total variance of yield in the both first and second years. Totally, results of stress tolerance indices in this research showed that application of the 75% recommended chemical fertilizer together with biofertilizer not only increased yield but also resistance of experimented variety to drought stress.

To study the effect of different fertilizing systems on the seed yield and phosphorous absorption in annual medic (var. Robinson)، an experiment was conducted based on a complete randomized blocks design with three replications in two locations in Kermanshah province، Iran. The treatments consisted of Control (no fertilizer application)، Chemical fertilizer (urea chemical fertilizer + triple superphosphate fertilizer)، Urea chemical fertilizer + phosphorous solubilizing bacteria، urea chemical fertilizer + mycorrhiza، Urea chemical fertilizer + phosphorous solubilizing bacteria + mycorrhiza، Nitrogen fixing bacteria + triple superphosphate fertilizer، Nitrogen fixing bacteria + phosphorous solubilizing bacteria، Nitrogen fixing bacteria + mycorrhiza، Nitrogen fixing bacteria + phosphorous solubilizing bacteria + mycorrhiza. The results of this research showed that under the conditions of this experiment The highest content Phosphorus content in pods (0. 47 %) and Soil seed bank (838 pods/m²) was found in treatment T6 (nitrogen fixing bacteria + phosphorussolubilizing bacteria). The highest content Phosphorus content in pods (0. 47 %) and Soil seed bank (838 pods/m²) was found in treatment T6 (nitrogen-fixing bacteria + phosphorus-solubilizing bacteria). It seems that inoculation annual medic var. Robinson withnitrogen fixing + phosphorous solubilizing bacteria،، indicating the synergistic interaction between these groups of bacteria to increase، soil seed bank as well as seed phosphorous content of annual medic var. Robison was found in control treatment.

In order to study the effect of different N fertilizer on berseem forage in an intercropping with basil, this experiment was conducted in Research Farm of College of Agriculture, University of Tehran during growing season 2011. Experimental treatments were arranged as split plots based on a randomized complete block design with three replications. Different fertilizers consisted of control (no N fertilizer), 100% chemical fertilizer, biological fertilizer, and integrated fertilizer (biological fertilizer + 50% N fertilizer) were assigned to the main plots while different additive intercropping patterns of basil mono cropping (weed free), basil mono cropping (weed infested), berseem clover mono cropping (weed free), berseem clover mono cropping (weed contaminated), berseem clover + %25 basil, berseem clover + %50 basil, berseem clover + %75 basil, berseem clover + %100 basil were assigned to the sub plots. The biological fertilizer comprised of Rhizobium (Rhizobium trefoli) + Azotobacter (Azotobacter sp.) + Azosprilium (Azosprilium sp.) + Bacillus (Bacillus sp.) + Mycorrihza (Mycorrihza sp.). The results showed that the highest basil forage yield (two harvests) (4223 kg.ha-1) was obtained from basil mono cropping (weed free) treatment when received integrated fertilizer. The highest forage yield (4833 kg.ha-1) for berseem clover was obtained from clover mono cropping (weed free) at 100% chemical fertilizing treatment. The highest total forage yield (berseem clover + basil) (5983 kg.ha-1) was obtained from berseem clover + %50 basil and berseem clover + %75 basil at integrated N fertilizer treatment. The best Land Equivalent Ratio and Relative Competition ratio were obtained at berseem clover + %75 basil and berseem clover + %100 basil treatments. Our results suggested that integrated fertilizer could be considered as the best fertilizing system to substitute for chemical N fertilizer (Urea) in additive intercropping of berseem clover and basil.