Journal of Agricultural Science and Sustainable Production
Year:2019 | Volume:29 | Issue:2 |Papers Count:20

The effects of different tillage practices, cover crop and intercropping on yield and yield components of pumpkin by factorial split plot experiment based on randomized complete block design with three eplications was studied at the Experimental Field of Bu-Ali Sina University, Hamedan. Treatments comprised three levels of tillage practices including NT: no tillage, MT: minimum tillage (chisel plow + disk), and CT: Conventional tillage (moldboard plow + disk); and two levels of cover cropping including C1: Lathyrus sativus as a cover crop and C2: no cover crop and three levels of cultivation systems as I1: additive intercropping of 50% green bean+pumpkin, I2: pure green bean, and I3: pure pumpkin. The results showed that seed yield, number of seeds per fruit, fruit diameter, fruit weight, fruit yield, seed weight of pumpkin as well as green bean yield were affected by management practices. The highest amounts of these traits were revealed at pure standing of each crop under conservation tillage with using legume cover crop. For example, pumpkin seed yield (121. 40 g. m-2) in pumpkin sole crop treatment was significantly more than the treatment of 50% green bean+pumpkin (127. 60 g. m-2). Minimum tillage and chickling pea cover crop treatment showed the highest amount of pumpkin seed yield (138. 3 g. m-2), but, minimum tillage and chickling pea cover crop treatment had no significant difference with no tillage and chickling pea cover crop treatment for this triat. The lowest pumpkin seed yield (110. 2 g. m-2) was achieved at conventional tillage and no chickling pea cover crop treatment. In general, according to the LER index, the best management was the additive intercropping of green bean with pumpkin under using conservation tillage and legume cover crop.

Legumes have dual symbiosis with arbuscular mycorrhizal fungi (AMF) and rhizobia. AMF are obligate biotrophs, known to play an important role in ecological processes. Legumes root forms nodules in symbiosis with rhizobia, which can fix atmospheric nitrogen. A factorial complete randomized block design with three replications was carried out under greenhouse conditions. Four levels of nitrogen (0, 2, 6 and 10 mM as nitrate), in Newman and Romheld nutrient solution were applied to the pots containing 1. 5 kg sterile sand. Surface sterilized seeds of clover plants (Trifolium repens L. ) were sown in pots and inoculated with arbuscular mycorrhizal fungus (Rhizophagus irregularis) and/or Rhizobium leguminosarum bv. trifoli. The control plants were left un-inoculated. The pots were daily irrigated with nutrient solution possessing the nitrogen levels. Clover plants were harvested after 12 weeks of growth and Shoot and root dry weights, root mycorrhizal colonization, nodule weights and numbers, nitrogen, phosphorus and potassium contents in shoot and root were determined. The highest amount of phosphorus was observed in mycorrhizal treatment at 0 and 2 mM nitrogen levels. At all levels of nitrogen, the presence of fungi increased the amount of root phosphorus. At all levels of nitrogen, the presence of bacterium significantly increased the amount of shoot nitrogen. The highest amount of shoot potassium (64. 4 mg. pot-1) was recorded at 2 mM nitrogen and non-mycorrhizal root and the highest amount of root K (19. 02 mg. pot-1) was seen at 2 mM nitrogen and in the presence of mycorrhizal fungus. The highest amount of shoot dry weight (4. 46 g. pot-1) was recorded in the mycorrhizal plants treated with 2mM nitrogen. The rhizobial inoculation had pronounced effects on root mycorrhizal colonization. By increasing nitrogen level up to 6 mM, the root colonization increased and the highest root colonization (34. 1%) was achieved in this treatment. The highest increase in number and fresh weight of nodules were obtained in co-inoculated plants. In the presence of mycorrhizal fungus, the number and fresh weight of nodules increased by 26. 44 and 20. 98%, respectively.

Life Cycle Assessment (LCA) is an approach to study the environmental impacts of product production or activities that are calculated based on two indicators of resource consumption and emissions. This study aims to investigate the environmental effects of the production of Bell pepper using The Life Cycle Assessment Technique was conducted during the years 2011-2017. The first information was obtained through the organization of Jihad-e-Agriculture and interviews and interviews from 260 statistical population with 152 farmers who were determined by the Cochran formula in Dezful In order to analyze environmental impacts, the ISO 14040 method was used for a functional unit equivalent to one ton of Bell pepper. The global warming, acidity, evacuation of water resources, fossil, phosphate and potassium comprise six groups of studied effect. The results showed that CO2 and NH3 pollutants in the form of groups of effect of global warming and acidity in the Bell pepper culture system had the highest effect. The values of environmental index (EcoX) and resource depletion index (RDI) were calculated 0. 0492 and 0. 4806, respectively. The effects of sensitivity and phosphate discharging sources respectively have the highest potential for environmental damage in the group of environmental impacts and Evacuated resources. Therefore, management of the use of urea fertilizer and the replacement of some of it with organic and non-chemical resources in agricultural indigenous peoples in order to reduce the environmental pollution of Iran is indispensable and inevitable.

Analysis of the ecological footprint in agriculture is a new and evolving subject that indicate, amount of land needed to compensate for the environmental effects of various agricultural activities. The main purpose of the study was to assess environmental sustainability of potato and cucumber cultivation in Sofalgaran District of Bahar County with using ecological footprint analysis. The quantitative approach and survey method were used and data was collected through questionnaires using a cross-sectional in period 2015-2016 crop years. Sample size were 100 potato farmers and 50 cucumber farmers. In order to assessing sustainability, based on energy consumption with environmental indicators such as; seed, water, fuel, labor, fertilizer, pesticides, potato and cucumber production were used. The sustainability comparison criterion was the global hectare (g ha) that calculated from the estimation of the ecological footprint model for each product. The results showed that both cultivation are considered unsustainable and there was a significant difference between the total ecological footprint per hectare in potato cultivation (4. 03) and cucumber cultivation (3. 23), so that cucumber cultivation has more environmental sustainability. According to the global hectare factor, both potato and cucumber cultivation are exploited more than the ecological capacity of a hectare productive land. However, ecological footprint of seed factor for potato cultivation with 24. 5% of global hectare and for cultivating cucumber, fertilizer factor with 22. 95% had the greatest impact on environmental unsustainability.

In order to investigate the effect of irrigation regimes and seedling age on rice yield and its components, present research was conducted as a split plot experiment based on randomized complete block design with three replications in Mazandaran province, Mahmoud Abad in 2017. The main factor included the irrigation method in three levels (flooding, saturation and low-irrigation) and the sub factor of seedling age at three levels (three, four and five weeks). The results showed that the effect of irrigation management only on the number of tillers and the effect of plant age on the number of tillers, panicle weight, straw yield and grain yield and harvest index were significant. Comparison of the average effect of irrigation treatments presented that the number of tillers in the flood treatment was the highest and in the low-irrigation (ecological) method the lowest was. Comparison of mean of simple planting effect of plant age displayed that the number of fertile tillers in the conventional treatment (4 weeks) was the highest and in ecological treatment (3 weeks) was the lowest. Regression analysis of panicle weight in different treatments at plant age level indicated a decrease in panicle weight. Therefore, 99. 5% of the weight loss was due to the age of the plant. Similarly, the relationship between planting age and rice yield showed a decrease in plant yield with increase of plant age. So, based on the explanatory coefficient, about 97. 5% of grain yield decreased due to age. Considering the no significant difference in grain yield at irrigation factor levels, and lack of ecological methods benefits in flooding (conventional), ecological treatments (low-irrigation level and 3th week) are recommended. The flexibility of the proposed techniques in the ecological method suggests that there are opportunities that will provide the ground for moving towards agricultural sustainability.

The present research was done in order to determine the suitable planting date and seed rate and to evaluate the seed and oil yields and chlorophyll rate of spring oilseed rape in Tabriz plain climate (cold and semi-arid in the Copen climate classification system). The experiment was conducted as split plot based on a RCBD design in 3 replications with two factors including sowing date (30 March and 9 and 19 April) and seed rate (4, 6, 8 and 10 Kg seeds per hectare). The RGS003 as adapted and superior genotype was used for cultivation. The study was carried out in East Azarbaijan Agriculture and Natural Resources Research and Education Center (Khosrovshah station) during the 2018 year. The results indicated that plants in the 30 March planting date had significantly higher values of field ground cover percent, Leaf chlorophyll index, plant height, pods per plant, 1000 seeds weight, seed oil percent and seed and oil yields. Having sufficient time for growth and establishment, these plants produced higher yields via maximum use of environmental factors. Correlations among the field ground cover percent, Leaf chlorophyll, plant height indices, with each other and seed yield components (except seeds in pod), seed and oil yields were significantly positive. These indices had an important role in yield determining. Finally, the most seed and oil yields including 1673 and 694 Kg. ha-1 respectively, were achieved from 30 March planting date with 6 Kg. ha-1 seed rate for RGS003 as spring cultivar at Tabriz plain.

In order to investigate the effect of late-season drought stress on some physiological traits, yield and yield attributes, a two-year field trial was carried out at the research field of Seed and Plant Improvement Institute, Karaj, Iran, on 2015-2017 growing seasons. Factorial arrangement of the treatments was set up as randomized complete block design with three replications. Experimental factors consisted of irrigation regimes (normal irrigation and withholding irrigation from silique setting stage until the end of the growing season) and 17 new winter genotypes of rapeseed. Several physiological traits included relative water content (RWC), total chlorophyll, proline as well as grain yield and yield attributes as dependent variables were measured. Results showed that amount of total chlorophyll under withholding irrigation was reduced (21. 65 percentage) reduced compared to the normal irrigation, while leaf proline content was increased by 28. 04 %. According to the findings of this study, superior genotypes were not necessarily top in terms of proline. Averaged over both years, Artist genotype produced highest grain yield (5043. 25 kg. ha-1) under normal irrigation condition, while L72 and HL3721 had highest grain yield (3915. 25 and 3892. 45 kg. ha-1, respectively) under withholding condition. It is worth noting that this advantage was mainly revealed to increased source capacity (number of silique plant-1, silique length and number of seed silique-1) as well as the superiority of chlorophyll content and relative water content of the leaf.

Water shortage is one of the most important limiting factors for plant growth around the world. To cope with this phenomenon, several solutions have been proposed, including the use of microorganism with plant growth promoting traits such as Trichoderma. Accordingly, an experiment was conducted to investigate the effect of three fungal species on tomato growth factors, as well as nutrients uptake by the plant in water deficit stress conditions in a factorial arrangement based on randomized complete block design. Treatments including T1 (Trichoderma longibrachiatum KH), T2 (T. longibrachiatum MA), T3 (T. harzianum), NT1 (negative control-without fungi) and NT2 (positive control – without fungi and with chemical fertilizer) at three moisture levels consist of W0 (none stress), W1 (medium stress) and W2 (severe stress), performed in three replications. The results indicated that dry weight of shoot and root and nutrients’ uptake decreased in all treatments as water stress increased, but this reduction was significantly lower in fungal treatments. Under none stress condition (W0), T1 and T2 treatments increased N and P absorption and T3 fungal treatments increased Fe and Zn absorption significantly. By increasing stress conditions, most of the measured parameters of the plant in fungal treatments were reduced except for T1 treatment. Under severe stress condition (W2), T1 enhanced dry weight (32. 8%), N uptake (62. 7%), P (34. 78%), Fe (39. 3%) and Zn (47. 6%), compared to negative control.

In order to evaluate the effects of tillage methods on soil organic matter (OM) content and crop yield, a field experiment was conducted under wheat-corn rotation based on split-plot design in three replications at Zarghan, Fars province. Results showed that the reduction of soil tillage operations accompanied by keeping crop residue can be improved OM content compared to conventional tillage (CT) methods. At a soil depth range of 0-10 cm, the OM content increased two % by applying reduced tillage (RT) method and residue retention compared to CT method. In deeper soil layers, OM content enhanced one % by CT method and residue retention compared to RT method. Results showed that grain yield of wheat increased 24. 5% by applying RT method and corn residue retention compared to CT method. While, wheat yield decreased 48% by applying No-Till (NT) method compared to RT method. Furthermore, applying NT method and corn residue retention increased wheat yield by 21% compared to crop residue removal. In wheat residue retention, results showed that kernel yield of corn increased by 34% under CT and RT methods compared to NT method. In contrast, keeping wheat residue accompanied by NT method application can be increased kernel yield of corn at 5. 5% compared to crop residue removal. It is concluded that, to maintain the crop yield potential and increase OM content under a consecutive corn-wheat rotation in arid and semi-arid regions, adopting RT method accompanied by keeping crop residue (standing residue with a height of 30 cm), is recommended.

In order to study the effects of drought stress and delayed cultivation on grain yield, oil yield and grain fatty acid composition in canola at autumn Cultivars, a field experiment was conducted as split-plot and as Randomized Complete Block Design (CRBD) with three replications in Seed and Plant Improvement Research Institute of Karaj, Iran in 2014-2016. Experimental treatments were included sowing dates in two levels included 20th of October (normal cultivation) and 5th of November (delayed cultivation), Irrigation in 2 levels included: full irrigation (control) and drought stress (irrigation withholding in pod formation) as well as hybrids and canola autumn cultivars included Neptune, Elvise, Okapi, Tassilo, GKH0224, GKH2624 and GKH3705. Results showed that irrigation withholding in pod formation stage decreased Seed yield, oil yield, and number of grain per pod, number of pods per plant, chlorophyll content, oleic acid, and Linoleic acid content. Whereas erucic acid and palmitic acid content were increased. The highest grain yield (5354 kg. ha-1) and oil yield (2443 kg. ha-1) were in full irrigation and normal cultivation. And the lowest of them were observed in irrigation withholding in pod formation stage and delayed cultivation. The highest content of palmitic acid was observed in GKH3705 cultivar, sowing date of delayed cultivation and irrigation withholding in pod formation stage. Also the minimum amount of it was obtained in normal cultivation, Neptune cultivar under full irrigation conditions. The cultivar of GKH3705 was the most appropriate in terms of the number of seeds per pod, oil yield, saturated and unsaturated fatty acids, and chlorophyll content. According to the results, on delayed cultivation and the GKH3705 cultivar under normal irrigation and drought stress can be recommended.

In order to study the physiological responses of castor to foliar application of zinc nano-chelate and humic acid under limited irrigation, an experiment was conducted as split-factorial based on randomized complete block design with three replications in Damghan region during 2015-16 growing season. Irrigation as the main factor in three levels including normal irrigation (control), irrigation up to 75 BBCH (mild stress) and irrigation up to 65 BBCH (severe stress). Combination of spraying various concentrations of humic acid (non-application, application of recommended rate and two-fold recommended rate) and zinc nano-chelate (application and non-application) were as subplots of this experiment. The results showed that the effect of irrigation treatment, humic acid, and zinc nano-chelate were significant on the number of capsules, number of seeds, 100-seed weight, grain yield, oil percent, and chlorophyll content. Irrigation up to 65 BBCH resulted in a reduction of 11. 9, 34. 9, 24. 2, 24. 9, and 51. 7 percent in 100-seed weight, grain yield, biological yield, percent and yield of oil compared to normal irrigation. With application of humic acid based on recommended amount obtained the highest grain yield (2098. 8 kg. ha-1). Foliar application of zinc nano-chelate resulted in 14. 4, 8. 4 and 18. 4 percent increase in the grain number, 100-seed weight, and grain yield. The highest oil content (45. 4%) and oil yield (943. 3 kg. ha-1) were obtained in the normal irrigation. The non-application of humic acid, as well as irrigation up to 65 BBCH, led to decrease in leaf chlorophyll content. The highest activity of superoxide dismutase enzyme was observed in non-application of zinc nano-chelate and two-fold consumption of humic acid under irrigation up to 65 BBCH conditions. The seed oil percent had a positive correlation with functional traits and total chlorophyll content and had a negative and significant correlation with antioxidant enzymes activity. Regression results showed that capsule number, 100-seed weight, grain yield, and oil yield were the main factors affecting seed oil percent. In general, the application of humic acid with recommended amounts and zinc nano-chelate led to improvement of growth and physiological traits and tolerance to limited irrigation in castor plant.

The effects of supplemental irrigation and biofertilizers on yield and yield components of Sardary wheat cultivar, were studied by an field experiment as split plot based on randomized complete block design at Research Station of the University of Kurdistan in 2013-2014 growing season. Factors consisted of three irrigation levels: without irrigation, irrigation at flowering stage and irrigation during grain filling were assigned to the main plots, and five fertilizer levels: Nitrokara biofertilizer, Phosphate Barvar2 biofertilizer, Nitrokara + Phosphate Barvar2 biofertilizers, Nitrokara + Phosphate Barvar2 biofertilizer + 50% chemical fertilizer and 100% chemical fertilizer were allocated to subplots. The results of analysis of variance showed that the effect of irrigation was significant on dry weight, plant height, and spike length, number of spike per unit area, seed number per spike, 1000-grain weight, grain yield, and seed protein content. Integrated application of biological fertilizer (Nitrokara and Phosphate Barvar2) along with chemical fertilizers produced the highest seed yield (319. 9 g. m-2). The lowest grain yield was obtained from Nitrokara (227. 3 g. m-2) treatment. Our results showed the positive impact of irrigation at flowering and grain filling stages and inoculation of biological fertilizers (Nitrokara and phosphate Barvar2) with 50% chemical fertilizer on dry weight, number of seeds per plant, 1000-grain weight and grain yield. Integrated application of biological and chemical fertilizers while meeting the nutritional needs of the plant and incresing seed yield, could significantly reduce the use of chemical fertilizers. According to the results of this experiment, a supplementary irrigation during flowering or seed filling stage was effective in increasing the yield of rainfed wheat.

Stevia (Stevia rebaudiana) is a source of strong, natural and free of calorie sweetener that is mainly used in industries and pharmacy. With respect to the importance of this plant, extracting sweetening compounds from this demands production of considerable biomass. Therefore, the effects of mychorrhizal fungus on some characteristics of Stevia’ s root organ were studied in a factorial experiment based on completely randomized blocks with 4 replications conducted in a greenhouse at Mohghegh Ardebili University in 2014. The first factor included Imma & Angel and Novell nutrient solutions; the second factor included the Planting bed that consisted of Leaf composts vermicompost, and Peat and perlite, and finally, third factor included the inoculation with mychorrhizal fungus and control treatment. The results showed that the highest percentage of root colonization with mycorrhizal was associated with the Novella nutrient solution and vermicompost planting bed, the maximum length of myrrhizae roots and dry weight of the mycorrhizal roots of the Imma & Angel solution and the vermicompost planting bed. In addition, Novell in vermicompost planting bed yielded the largest Leaf dry weight, root volume, root surface and root length after inoculation with mychorrhizal fungus. The largest, root dry weight was observed in case of Imma & Angel solution in vermicompost medium (inoculated with mychorrhizal fungus).

Self-incompatibility in apricot (Prunus armeniaca L. ) trees and their need for pollination with other cultivars results in unsustainable yield and loss of traditional production. Study of pollen compatibility among different cultivars is needed to guarantee of fertility outcome and sustainable fruit production in new apricot cultivars. In current work, the final fruit set was studied for apricot promising genotypes after controlled cross-pollination in the field conditions in two successive years. Also, their (in) compatibility statues was evaluated by tracking of pollen tube growth through the ovary by fluorescent microscopy approach. The presence of at least one growing pollen tube inside the ovary 96 h after pollination was considered as the sign of compatibility, but block of pollen tube growth through the style was considered as the sign of incompatibility between pollinizer and recipient genotypes. According to our data, all of pollinizers include of GER, Aybatan, HB190, NM177 and KOSH269 were compatible with recipient genotypes. However, the most percentage of final fruit set in Ordoubad90 was achieved when it was pollinated with NM177 and Aybatan pollinizers, in ASG and AD503 genotypes were achieved when they were pollinated with Aybatan and GER pollinizers, and finally in AD740 genotype was achieved when it was pollinated with NM177, Aybatan and GER pollinizers. Additionally, AD503 had more (47% fruit set) but Ordoubad90 had less (23% fruit set) fertility potential among recipient genotypes. Also, microscopic observations confirmed the results of final fruit set following controlled cross-pollination in the field.

In order to investigate the effect of using wild species as a rootstock in grafting plants on salinity tolerance in tomato, a factorial experiment in a randomized complete block design were conducted. The first factor was grafting including Money maker non-grafted (M), Money maker self-grafted (M+M), Money maker grafted on S. pimpinellifolium LA0722 (M+P1) and Money maker grafted on S. pimpinellifolium LA 2184 and the second factor was three concentration of NaCl including the 0, 40 and 80 mM along with Hogland nutrient solution that were applied to tomato in the hydroponics greenhouse, Department of Horticulture, University of Tabriz. The results showed that the increasing salinity had a negative effect on leaf area and yield, and total fruit number in tomato cv. Money maker, the use of S. pimpinellifolium as rootstock showed the best performance under different salinity conditions. Also, in the highest salinity concentration, the lowest sodium content was observed in the plants grafted on S. pimpinellifolium LA0722. The results indicate that, use of pimpinellifolium as rootstock in 80mM NaCl level had 69% higher fruit yields than the non and self-grafted Money maker plants.

To evaluate the effects of different levels of gamma irradiated and non-irradiated sewage sludge on uptake of micronutrients (copper, zinc, iron, nickel and manganese) and heavy metals (cadmium and lead) in root and shoot of basil, a greenhouse experiment was conducted in a completely randomized design with three replications. The treatments consisted of 0, 15, 30 and 60 g. kg-1 of sewage sludge exposed to gamma radiation at doses of 0, 5, 10 and 20 kGy. The results showed that addition of 15 and 30 g sewage sludge kg-1 soil with each irradiation dose increased root and shoot dry weights and reduced their at 60 g. kg-1. The application all levels of irradiated and non-irradiated sewage sludge increased the uptake of copper, nickel, lead, zinc, manganese and iron in root and shoot compared to the control. The maximum uptake of copper, zinc, iron, manganese, lead, cadmium and nickel in root and copper, zinc, lead and cadmium in shoot was obtained in 30 g. kg-1 sewage sludge irradiated with 20 kGy absorbed dose. The maximum uptake of iron, manganese and nickel in shoot was revealed in 30 g. kg-1 sewage sludge irradiated with 5, 5 and 10 kGy, respectively. The results showed that the basil herb has the high ability to absorb and transfer of metals to shoot. Therefore, the use of basil plants treated with sewage sludge in human nutrition as fresh and spicy should be done with caution.

In order to investigate the effect of Mung bean density on weed suppression and sesame yield, an experiment was conducted at Research Farm of Sari University of Agricultural Sciences and Natural Resources as randomized complete block design (RCBD) with three replications in 2015. The treatments consisted of three levels of Mung bean density (5, 10 and 15 plants. m-2) and two check treatments (no cover crop at weed free and weed infected at full season). The results of variance analysis indicated that treatments on Mung bean biomass, weed density and dry weight and all traits considered (except 1000 seed weight and harvest index) of sesame affected significantly. Mung bean biomass had a nonlinear increase with increasing density and the highest its biomass (648 g. m-2) was obtained at 15 plants. m-2. Means comparison showed that dry weight of total weeds at Mung bean densities of 5, 10 and 15 plants m-2 was reduced compared with weed-infected treat at no cover crop conditions by 84, 89 and 90%, respectively. Weed interference reduced 57% sesame seed yield at no cover crop conditions. Sesame seed yield increased by 56, 81 and 97% at densities of 5, 10 and 15 plants. m-2, compared with weed-infected treat at no cover crop conditions. The highest value of cover crop-weed index (3. 54) was obtained at Mung bean density of 15 plants. m-2, which in terms of weed control efficiency, the control was sufficient. In achieving sustainable agriculture goals using Mung bean (as cover crop) in sesame, weeds can be managed and favorable yield has been achieved.

The effect of mulching and biofertilizer on qualitative and quantitative traits of purslane in intercropped with dragon’ s head, examined by a field experiments with a factorial arrangement based on randomized complete block design with three replications at the Research Farm of University of Tabriz during two growing seasons of 2015 and 2016. Cropping systems including sole cropping of purslane and dragon’ s head, additive intercropping of dragon’ s head + purslane (20, 40, 60 +100 %) were evaluated as the first factor, mulch application including wheat straw mulch and no mulch as the second factor and two types of fertilization including application of 100% chemical fertilizer and 50% chemical + biological fertilizers as the third factor. The results showed that mulch application significantly increased the number of branches, plant height, yield, oil content and omega-3 of pursulane and decreased leaf temperature. The highest number of branches (7. 19) and yield (47. 26 g. m-2) were observed in sole cropped and second year; while the highest plant height and lowest soil temperature was observed in D60 + P100 cropping pattern. Also, neither all of the traits were significantly affected by fertilizer treatment. The highest land equivalent ratio (1. 56) and relative value total (1. 27) were obtained from dragon’ s head with purslane intercropping (D40 + P100) and mulch application and combinative application of chemical and biological fertilizers. Total actual yield loss for most of the intercropping combinations was greater than zero, which indicates the superiority of intercropping to monoculture.

Soil contaminations with crude oil and its derivatives are among the most dangerous types of environmental pollution. One of the many types of bioremediation is a phytoremediation. In the present research, first, contaminated soil was collected from Tabriz refinery and then study was conducted on phytoremediation methods of petroleum hydrocarbons. For this purpose, after isolation of hydrocarbon degrading bacteria from contaminated soil, various phytoremidiation treatments were tested. The treatments included the use of two types of plants; Agropyron and Tall fescue in the both cases of with and without inoculation of five bacterial consortium, Stenotrophomonas sp. COD 1-1, Psedochrobactrum sp. COD 1-4, Arthrobacter sp. COD 2-3, Shewanella sp. COD 2-1 and Stenotrophomonas sp. COD 5-6 and mycorrhizal-like fungus (Piriformospora indica), and combined treatment (including inoculation with bacterial consortium and fungi adding cow manure and Tween 80 as a surfactant), moreover, one combined treatment without culture of plant was added to the test. After the end of the experiment, which prolonged four months, the indicators of total petroleum hydrocarbon (TPH), soil enzymes health indices (dehydrogenase, urease and catalase), soil biological indices (basal respiration and substrate-induced respiration) and plant growth indices (shoot and root dry weight and crown number) were measured. Regarding the results of plant growth and its matching to the rate of degradation of oil hydrocarbons, it was observed that Tall fescue plant, inoculated with mycorrhizal-like fungus, had the ability to decompose oil compounds by 68%, and non-inoculated Tallfescue was able to degrade the 43% of petroleum hydrocarbons. Agropyron inoculated with bacterial consortium had 66% ability of TPH degradation and Agropyron without inoculum was able to degrade the 53% of petroleum hydrocarbons. The activity of dehydrogenase and urease enzymes was high in the first week of the experiment and decreased significantly after 4 months, and in contrast to catalase activity was lower in the first week and increased at the end of the experiment.

The main purpose of this study was to investigate the evaluation the sustainability of the wheat and maize agroecosystems in Sanjabi area in Kermanshah province in the period from 2014 to 2016. The study carried out as survey method and research tool was questionnaires. The questionnaires were developed based on Likert scale as closed and multiple choice questions that filled by interview. Sample amount were 56 and 92 for wheat and maize farmers respectively based on the target community and Cochran formula. The results showed that the wheat and maize agroecosystems were better in environmental and economic indices significantly. However there was no significant difference between agroecosystems in social factors. The results showed that only 4. 4 and 8. 1 percent of wheat and maize farms were managed as sustainable. In general, the relative advantages of maize farms in economic indices compare to wheat farms resulted in forget the environmental hazards of maize cultivation. However, the maize economic sustainability reduces strongly if water productivity is considered. Finally, non chemical methods of weed management and pest control may result in higher sustainability in maize and wheat agroecosytems respectively.