yaser alizadeh

To study the effect of deficit irrigation (DI) and partial Root-Zone Drying (PRD) on yield and physiological characteristics of mungbean, a field experiment was conducted as a split plot experiment in a randomized complete block design with three replications and nine treatments at the research farm, Faculty of Agriculture, Ilam University during growing season in 2022. Treatments included three levels of deficit irrigation (100 (without stress), 70 (moderate stress) and 50% (severe stress) of field capacity) as main plots and three irrigation methods including; usual irrigation, fixed partial root-zone drying (FPRD) and alternative partial root-zone drying (APRD) as subplots. Results showed that the highest yield (2187.37 kg.ha-1) and total chlorophyll (2.28 mg.g-1fresh weigh) in the treatment without stress and usual irrigation and the lowest yield (570.70 kg.ha-1) and Total chlorophyll (1.11 mg.g-1fresh weigh) was obtained under severe stress conditions and usual irrigation method. Drought stress increased the content of malondialdehyde (32%), catalase (69%) and ascorbate peroxidase (63%) compared to non-stress conditions. In severe and moderate stress, the use of APRD compared to usual irrigation, increased yield, RWC, photosynthetic pigments and antioxidant activity in mung bean plants. However, these effects were not observed in the FPRD. In moderate stress, APRD with water saving showed a yield close to that of the control treatment. The results showed that in deficit irrigation, APRD was effective in reducing the effects of drought stress in the mung bean plant.Keywords: Antioxidants, drought stress, Chlorophyll, Proline

The limitation of water resources, increase in water demand for food supply, land use changes, climate change, and reduction of soil fertility are the most important challenges facing the world's food security. Various approaches have been used to reduce water demand and increase production per unit area of ​​agricultural products, including modifying cropping patterns and planting methods, using scheduled deficit irrigation, and implementing new policies and laws in water resources management. Among these approaches, some researchers suggest that intercropping is the most sustainable method to improve the use of production resources. The intercropping system is the simultaneous growth of two or more crops in one part of the land. Intercropping has potential benefits such as higher crop yields, more efficient use of resources (sunlight, water, and fertilizers), reduced disease and pests, and improved environmental conditions. The intercropping farming can be an efficient solution to improve the productivity of water resources, especially in areas with limited water resources such as Iran. So far, no study has been conducted on the efficiency of water and land use in the maize-mung bean cropping system. So, the purpose of this study was to investigate the effect of maize-mung bean intercropping in different cropping patterns and different water stress conditions on water productivity.

The field experiment was a split plot experiment based on a randomized complete block design with three replications in the research farm, Faculty of Agriculture, Ilam University during the 2020-2021 growing season. Treatments included four levels of irrigation including 40, 60, 80, and 100 % of crop water requirement as main plots, and four planting pattern levels including additive intercropping series (100 % corn + 50 % mung bean), replacement intercropping series (50 % corn + 50 % mung bean) and monocultures of mung bean and corn, as subplots. The application of drought stress started after the establishment stage of the plant and continued until the harvest. The irrigation requirement was determined based on the TDR method and was applied using the drip irrigation method. At the end of the growth period, some parameters of both plants were measured, including plant height, thousand seed weight, grain yield, biological yield, and harvest index. Moreover, water use efficiency (WUE), land equality ratio (LER), and water equality ratio (WER) indicators were used to check the effectiveness of the intercropping system. Finally, analysis of variance (ANOVA) was performed using Minitab 17 software, and the means were compared by Duncan's test at a 5 % probability level (p≤0.05).

The results showed that the water use efficiency of mung bean was significantly lower than that of mung bean monoculture in two patterns of mixed and incremental cultivation. The highest mung bean water use efficiency occurred at the irrigation level of 80% of the water requirement and single crop (0.51 kg m-3). Maize water productivity in all cropping patterns decreases with increasing irrigation water consumption. There was no significant difference between the water productivity of the additive intercropping and the monoculture of maize, but the water productivity of the replacement intercropping had a significant difference with the other two cropping patterns. The highest value of LER was obtained in the additive intercropping as 1.56 and 1.52 in 80 and 100% of water requirement, respectively, which was equivalent to a 56 and 52% increase in profitability compared to a monoculture of the two species. WER was greater than 1 in all water levels and two intercropping patterns, which indicated the superiority of intercropping with less water than monoculture. Also, the results showed that the highest WER value was 1.46 in the additive intercropping treatment with an 80% water consumption level. Additionally, the comparison of LER and WER indices showed that intercropping makes more efficient use of water and land resources. Also, the results indicated that the highest LER and WER occurred in the additive intercropping and the irrigation level was 80%. Therefore, additive intercropping and the use of an 80% irrigation level make the most efficient use of water and land resources.

The higher WER and LER indexes in this study suggest that an intercropping system may save 45%–56% of water and farmland, achieving similar yields in comparison to sole maize and sole mung bean. Thus, the intercropping system would be an advantageous cropping system for sustaining crop productivity and improving water and land use efficiency. However, additional research is required to comprehend the resource capture mechanism of intercrop species in intercropping systems under the changing climate. Especially, a series of comprehensive studies to develop the best management approaches regarding fertilization, irrigation, and pest control would support the sustainability of intercropping systems and farmer adoption. The successful adoption of the intercropping system will play an important role in meeting the food requirements of the increasing population, especially in arid and semiarid countries such as Iran which are facing challenges in resource limitation. The results of this study showed that by using intercropping system and optimal management of water consumption, it is possible to achieve performance similar to single crop cultivation with 45% less water and 56% less land use. However, more research is needed to understand the mechanism of how resources are absorbed by mixed species in intercropping systems, especially under different climatic conditions.

In order to investigate the effect of seed bed and organic fertilizers on the yield and yield components of chickpea and weeds, an experiment was conducted in the form of complete randomized designs with 3 replications in Chardavol Agricultural Research Station in 2019. Treatments include the usual bed and false seed bed as main plots and chickpea plant feeding at four levels (no fertilizer application, animal manure, humus fertilizer, and compost at a rate of 10 t/ha) as sub-plots. The results showed that the effect of cultivation types treatment on yield and seed, number of seeds per pod, number of pods per plant, and plant height was significant. Also, organic fertilizers had a significant effect on grain yield, number of seeds per pod, number of pods per plant, grain weight, and plant height. The interaction between seed bed and organic fertilizers was significant on yield at 5% level and on the number of pods per plant at 1% level. The highest number of seeds per pod, maximum grain weight, and highest grain yield of chickpea are obtained with 1 seed per pod, 36 g and 720 g in compost fertilizer treatment, respectively. The total weed density in the dryland chickpea field was up to 10% lower under false seed bed treatment. False seed bed was well able to control the weeds of dryland chickpea and the best fertilizer in terms of weed management and improving chickpea yield was compost.

Personal characteristics and abilities and reflecting on them, which is referred to as self-affirmation, can be the basis for increasing self-esteem, psychological and physiological well-being, academic progress and academic motivation of students. Therefore, the lack of a suitable tool to measure it in students, caused Harris et al. (2019) automatic self-verification measurement of translation and its psychometric characteristics to be investigated in this research. The current research is a descriptive research of the correlation type. The statistical population was all male students in the third grade of secondary schools in Ilam in the 2021-2022, of which 330 were selected by one-stage cluster random method. The obtained correlation was positive for convergent validity with the intrinsic motivation subscale of Harter (1980) (p<0.05) and negative for divergent validity with the depression, anxiety and stress questionnaire (DASS-21) of Lovibond and Lovibond (1995) (p<0.05). The obtained correlation was positive for convergent validity (p<0.05) and negative for divergent validity (p<0.05). In addition, the result of the study shows a desirable suitability of parameters. (RMSEA = 0.08, CFI = 0.944, GFI = 0.906, CMIN/DF= 3.21). The results of the factor analysis showed that the three factor model including abilities, values and social relations of this measure had the best fit with a suitable factor load (at least 0.70). The reliability of this measure was calculated using Cronbach's alpha method, whose coefficients were reported as 0.93 for the whole Measure, 0.85 for the first factor, 0.82 for the second factor and 0.87 for the third factor.

The aims of this study was to investigate the radiation and nitrogen use efficiency at different irrigation regime and nitrogen rate in Ilam climatic condition.

The experiment was conducted as a split-plot based on randomized complete block design with three replications in Agronomy Research Farm of Ilam University. The experimental factors included 3 irrigation regime (100, 80, and 60 percent of field capacity) and nitrogen rate at three levels (0, 100 and 150 kg.ha-1).

The highest grain and biological yield were obtained with 5275 and 17209 kg/ha in I100 N150 treatment, respectively. Radiation use efficiency of Maize was affected by irrigation regime and nitrogen rate. Radiation use efficiency was in the range of 1.97 (I60N0 treatment) to 2.66 g/MJ (I100 N150 treatment). The highest and lowest of radiation absorbed were obtained in I100 N150 and I60N0 respectively. The highest of nitrogen use efficiency of agronomic (47.5 kg/kg) and uptake (1.6 kg/kg) were observed in I100N0 treatment and the highest of nitrogen use efficiency of physiologic was obtained I80N0. Nitrogen uptake in harvested biomass increased with additional N fertilizer application. The nitrogen uptake increased from ∼65 kg/ha at I60N0 treatment to ∼280 kg/ha for I100N150 treatments.

In this study, an inverse relationship was observed between radiation use efficiency and agronomic nitrogen use efficiency. The results of the experiment showed that the application of higher nitrogen rate was not the appropriate strategy for compensating for the reduced grain yield under low irrigation.

In order to study the effect of intercropping (additive and replacement series) on yield and radiation use efficiency of safflower and chickpea, a field experiment was conducted based on a randomized complete block design with three replications and nine treatments at the research farm, Faculty of Agriculture, Ilam University during the growing season in 2020. Experimental treatments were include: sole crops: safflower (S) (25 plants.m-2) and chickpea (Ch) (25 plants.m-2), intercropping of replacement series: (70% S, 30% Ch), (50% S, 50% Ch), (30% S, 70% Ch) and intercropping of additive series: (100% S+ 30% Ch), (100%S + 50% Ch), (100% Ch + 30% S) and (100% Ch + 50% S). The results showed that the highest grain yield (190 kg.ha-1) and biological yield (1070 kg.ha-1) of safflower were obtained in additive series 100% S+ 30% Ch. The highest (1.47) and the lowest (0.86) land equivalent ratio was obtained from additive series 30% S+ 100% Ch and replacement series of 30%S+ 70% Ch, respectively. The highest radiation use efficiency (RUE) of safflower and chickpea was obtained in the treatments of 100% S + 30% Ch and 50% S + 50%Ch, respectively. The highest radiation absorbed (603 MJ.m-2) was obtained in the treatments of 100% S+ 50% Ch. Intercropping patterns of chickpea and safflower improved the radiation absorption and radiation use efficiency and increased the total yield per unit area and LER.

In order to investigate the light absorption and radiation use efficiency and grain yield of maize varieties in irrigation different levels, split plots experiment in randomized complete block design were conducted with three replications at Ilam University Research Field. Irrigation at three levels was assigned to the main plots (irrigation after 70, 105 and 140 mm evaporation from evaporation pan Class A) and four single cross corn hybrid varieties (524, 666, 677 and 704) were sub plots. Irrigation levels were significantly different in grain and biologic yields and harvest index. Grain yield decreased by 19% and 42% at I105 and I140 irrigation levels, respectively. Harvest index decreased by 0.8% at I140 Irrigation level. Results showed that maximum grain and biologic yields were observed in SC704, SC677 varieties, respectively. The effect of irrigation levels was significant on radiation use efficiency. The highest radiation use efficiency was observed in the studied varieties at I70 irrigation level (with an average of 2.43 g/mJ). Water deficit at I140 Irrigation level, radiation use efficiency was reduced by 25.11% relative to optimum moisture conditions. Based on the results, although all maize varieties showed reduced radiation use efficiency under drought stress, SC677 variety had the highest radiation use efficiency under stress and optimum irrigation conditions, compared to other varieties and cultivation of this variety is recommended, especially under stress conditions.

It is a strategic need to find drought-resistant tree species with the aim of reviving Zagros forests. There are no enough researches about the effect of nano particls on the woody plants especially on their physiological features, while most of recordes have focused on crops. Therefore, in the current research, we investigated the effect of Nano Sio2 on Wild Pistachio (Pistacia atlantica subsp. mutica) seedlings in order to finding a resistant plant for rehabilitation of Zagros forest.

The experiment was based on a completely randomized design with 126 seedlings, six treatments of Nano Sio2 (control, 100, 300, 700, 1500, and 3000 mg. l-1) for 30 days and three replicates at three levels of drought stresses (control, every other day of irrigation; moderate, every four days of irrigation; and severe drought, with no irrigation). At the end, the physiological characteristics such as chlorophyll a, b, total, caratoneid, carbohydrate, proline content, enzyme peroxidase of guaiacol and catalase were analysed in treated leaves seedlings.

The results showed that levels of drought stress decreased the chlorophyll, caratoneid contents and increased the soluble carbohydrates, proline, and antioxidant enzymes. In the other words, the seedlings reacted differently to nano Sio2 treatments that the highest amount of carbohydrates and catalase were observed in 700 mg.l-1; chlorophyll a, b, total and caratoneid in 3000 mg.l-1, and proline and peroxidase in 300 mg.l-1. Furthermore, the different levels of drought stresses made a reduction in the types of chlorophylls and caratoneid; increase in carbohydrates, proline, and antioxidant enzymes.

It can be concluded that the most physiological traits were increased under drought stress and the Sio2 nanoparticles mitigated some traits like types of chlorophyll and carotenoids. Concentrations of 300, 700 and 3000 mg. l-1 had a better effect on many of the physiological traits than the others. Reducing the types of chlorophyll and carotenoids and increasing carbohydrate, proline and antioxidant enzymes are occurred in plants to tolerate the drought stress. Due to the lack of basic information about the resistant mechanism in the endemic tree species from Zagros forest in response to nanoparticles, this study will be a great assistance to develop nano technology in wooden plants. It is suggested to study the effect of Sio2 nano particles for longer periods or on some more species that could be a considerable way to find reliable results. These results may lead into economical production of drought resistant seedlings in large scales. Keywords: Drought resistant; leaf physiological features; Sio2 Nano-particles; Chlorophyll; Pistachio.

Diversification of agriculture is considered an important strategy to overcome the challenges faced by many developing countries due to the opportunities it offers to face heterogeneous production conditions, increase income generation through entry into new markets, and risk management. Conservation of biodiversity is one of the sustainable development concepts in agriculture. Excessive attention to the number of products and the extreme use of off-farm inputs, regardless of other ecological functions of these systems, has led to the reduction of biodiversity at all levels. In this context, a comprehensive plan for monitoring crop diversity and identification of factors influencing diversification is necessary. Accordingly, this study was conducted to evaluate the temporal and spatial changes in the biodiversity of agricultural systems in the Ilam province during 2004 and 2016.

Data were gathered from statistical yearbooks and reports from the Plan and Budget Organization and Organization of Jihad Agriculture. Stepwise regression analysis was used to identify the factors influencing regional crop diversity fluctuation over time (Also, stepwise recursive regression analysis was used to evaluate the determinant factors in the changes of diversity in agricultural systems.). In order to evaluate the spatial variation of crop diversity in irrigated agroecosystems and its determinants factors, the Shannon-Weiner diversity index was calculated. Based on the assumptions of the study, the influencing factors on the spatial variation of crop diversity were classified into geographical factors, climate and ecological factors, sociocultural factors, economic factors, and management factors. Then, insignificant factors on crop diversity were excluded from the model and finally, the most important determinant on variations between different regions of the province remained in the model.

The findings of this study revealed that over the 12-years period, the general trend in the changes of production systems was a decreasing one; so the agricultural systems’ diversity in all counties, except for Ilam and Dehloran, had decreased, of which the highest value of the Shannon-Weiner diversity index was calculated 1.90 in 2016. The main reason for this increase in diversity was the increase in the number of vegetable crops and reducing the area under cultivation of dominant crops (wheat and barley) during the studied period. Furthermore, the main determinant factors of diversity in the agricultural systems of Ilam Province were the number of villages with inhabitants, average annual net income of a rural household, number of cooperatives, number of dusty days, agricultural land areas, number of production units, age of the beneficiary, minority percentage, amount of urea fertilizer, number of family members, and literacy rate, respectively.

Studying the critical points in the agricultural systems of Ilam Province indicated that the top-priority actions to improve sustainability and increase the diversity of these systems are educating farmers, helping them reach economic stability and improving production management and water resources management

stresses are considered as the most important limiting factors in agricultural production in the world. About two-thirds of Iran's agricultural lands are located in arid and semi-arid regions and face drought stress. After drying, salinity is one of the most important environmental stresses in the world and in Iran. Environmental stresses have a negative effect on the growth and development of reproductive organs and decrease the economic and biological yeild of the plant. These stresses also affect many physiological processes of the plant and cause changes in plant physiological traits. Studies have shown that the absorption of the most of nutrients in plants under salt and drought stress is reduced. Nitrogen is the first food ingredient that is lacking in saline areas and is an essential nutritious element of the plant. Considering the major contribution of maize in providing human food, livestock and industrial uses, as well as soil conditions of the country, organic matter shortages and climate change, the comprehensive study of the mutual relations of consumption and non-use of fertilizers is essential in the presence and absence of water stresses and salinity, according to optimal management of water and soil resources and fertilizers and finally the achievement of optimal yields. The experiment was conducted as split- split plot design in a randomized complete block design with three replications at the Research Farm of the Faculty of Agricultural, University of Ilam in 2017. The treatments consisted of four levels of salinity (S1 =fresh water, S2 = 2, S3 = 4 and S4 = 6 ds / m) from salt rock source as the main factor, three levels of irrigation (I1 = 100, I2 = 80 and I3 = 60 percentage of water requirement of the plant) as a sub factor and three levels of nitrogen fertilizer from urea source (N1 = 0, N2 = 100 and N3 = 150 kg/ha) were considered as the sub- sub factor. Treatments were applied, in the 5_6 leaf stage. Sampling was performed to measure physiological traits at flowering time and yield and yield components at harvest time. Data analysis was performed by SAS.9.2 software and the mean comparison test was performed by LSD test. Charts is drawn by Excel. Based on the results, the highest yield was obtained in non stress conditions and application of 150 kg ha-1 nitrogen. Interaction of stresses among functional traits had the most negative effect in grain yield with a 69% reduction, also, among three physiological traits, electrolyte leakage showed a three-fold increase in the effect of interaction treatments with increasing tensions. The number of seeds per ear, number of rows per ear, number of seeds per row, biological yield and harvest index were decreased by 59%, 40.6%, 40%, 65% and 46%, respectively. Application of nitrogen at all levels of stress also reduced the effects of stresses and increased yield. The relative water content of leaf, chlorophyll a, chlorophyll b, total chlorophyll and carotenoid were also significantly reduced by the dual effects of treatments. It was also observed that all examined traits at the highest level of stress had an almost identical response to N2 and N3 treatments. Therefore, it seems that application of 100 kg ha-1 of nitrogen in maize under stress is appropriate for increasing the plant resistance and reaching maximum yields. The results indicated that salinity and irrigation stress in all studied traits were significant. Increasing stresses increased ion leakage and decreased other traits. Nitrogen consumption under stress condition improved all traits. There was no significant difference between treatments for consumption of 100 and 150 kg ha-1 nitrogen except for biological yield. As a result, under severe stresses, consumption of 100 kg ha-1 of nitrogen seems to be more optimal.

Mung bean is a warm seasonal annual legume, grown mostly as a rotational crop with cereals like wheat. The crop’s main advantages are that, as a legume and that it has a short growth cycle (75-90 days), requires little water and fits easily into crop rotations with cereals. It grows well under most adverse arid and semiarid conditions. Plants in nature are continuously exposed to several biotic and abiotic stresses. Among these stresses, drought stress is one of the most adverse factors of plant growth and productivity and considered a severe threat for sustainable crop production in the conditions on changing climate. Drought stress disrupts photosynthetic pigments and reduces the gas exchange leading to a reduction in plant growth and productivity. Salicylic acid (SA) is a naturally occurring plant hormone, influences various physiological and biochemical functions in plants. It can act as an important signaling molecule and has diverse effects on tolerance to biotic and abiotic stresses. Salicylic acid plays a key role in providing tolerance to the plants, exposed to water stress. The exogenous SA application also enhanced the growth and photosynthetic rate in crops under water stress. The aim of this study was to investigate the effect of salicylic acid (include two method of seed priming and foliar application) on two cultivars of mung bean, under drought stress. In order to study the effect of exogenous application of salicylic acid on yield an physiological characteristic of two mung bean cultivars under drought stress an experiment was conducted as a split- split plots based on randomized complete block design with three replications in agricultural research farm of karezan of Ilam province in 2017. Treatments were 2 levels of irrigations (irrigation after 60 and 110mm evaporation from the evaporation pan) as main plots and 2 mung bean cultivars (Gohar and Mehr) as first sub plots and 3 levels of salicylic application (control, seed priming and foliar application) as second sub plots. Salicylic acid was sprayed in two steps: 1- Two weeks after emergence and five days before applying the stress, 2- Early flowering stage. Physiological characteristic were measured at flowering stage. Yield and yield components measured for each treatment separately in the physiological maturity time. Analyze of variance showed that the effect of interaction of cultivar, drought stress and salicylic application on the grain yield, biological yield, number of pod in plant and number of seed in plant were significant. The highest value of grain yield (1894 kg.ha-1) and biological yield (4997 kg.ha-1) were obtained in Gohar cultivar under without stress and foliar application of salisylic acid. Also, the application of salicylic acid, especially in drought stress conditions, increased the content of chlorophyll a, chlorophyll b and carotenoid. The highest (96%) and lowest (71%) relative water content were observed in non-stress treatment with salicylic acid application and stress treatment without salicylic acid, respectively. Exogenous application of salicylic acid improved the drought tolerance of mung bean by enhancing photosynthetic pigments, carotenoid and relative water content which ultimately increased the yield of mung bean. Under drought stress and non-stress conditions, the yield of Gouhar cultivar was higher than that of Mehr cultivar. But the difference between control treatment and application of salicylic acid treatment was higher, under drought stress condition. Application of salicylic acid was raised 70 percent of Mehr cultivar yield under drought stress condition

Crop rotations are practiced to eliminate the effect of monoculture, but the succeeding crop may be influenced by the phytotoxins released by the preceding crop. Among plants, Brassica species contain allelochemical compounds as glucosinolate that is, under special conditions, released to environment and affects seed germination and plant growth. Wild mustard (Sinapis arvensis L.) as a weed of 30 crops in 52 countries which has a series of allelopathic effects that prevent germination of other plants. Products of glucosinolate- like ionic thiocyanate (SCN-) inhibited the root or shoot growth of many crop species. Also volatile compounds like isoprenoid and benzenoid released from Brassica tissue degradation may suppress many crops growth. It was also found in many studies that allelochemicals, which inhibited the growth of some species at certain concentrations, might stimulate the growth of same or different species at lower concentrations. The present research was conducted to evaluate the effects of aqueous extract concentration of various mustard parts on barley seed germination and seedling growth. In order to evaluate the allelopathic effect of mustard in agro ecosystems, a factorial experiment based on completely randomized design with three replications was carried out in botany laboratory of agriculture faculty, Illam University in 2014. Experimental treatments included five concentrations of mustards foliage and root aqueous extract (0, 10, 30, 50, and 70 percent) that were studied at germination and early growth stage of barley (cv. Abidar) in two separate experiments. In the seed germination section, the effects of aqueous extract of mustard on germination rate and germination percentage of barley seed were measured. In the study of the effect of aqueous extract of mustard on barley seedlings, weight and length of root and shoot, leaf chlorophyll content, proline and soluble sugars content were measured. Results showed that the highest amount of barley seed germination percentage and germination rate (100 and 19.5, respectively) were observed in control and the lowest amount (40 and 9.5, respectively) belonged to mustard root aqueous treatment with 70 percent concentration. The most decrease in barley seedlings length and weight were observed at the highest concentration of aqueous extract. The amount of chlorophyll a decreased from 2.39 in control to 1.66 mg per fresh weight in 70 percent concentration of aqueous extract treatment. The highest amount of proline (66.8 μM per fresh weight) in barley foliage was observed in 70 percent aqueous extract treatment. The results from this study showed that mustard allelopathic effect may be a possible mechanism controlling the barley germination and early growth stage in agro ecosystems. Generally, we were able to demonstrate short term auto toxicity and possible short-term allelopathy due to mustard has harmful effects on barley including reduced seed germination and emergence of barley seedling. Depending on the concentrations of Mustard extract, allelopathic activity will vary Mustard. Further investigations are also needed to determine the influence of cultivar variations, and to identify the active compounds involved in mustard auto toxicity and Allelopathy.    Highlights: 1-Mustards aqueous extract reduced seed germination percentage and plant growth in barley. 2-Mustards aqueous extract increased proline and soluble sugars in barley, but it reduced amount of chlorophyll in this plant.

Investigating whether agricultural ecosystems are performing as carbon source or sink due to either natural influences or management approaches plays a critical role in studies aimed at mitigating and adaptating to climatic variation. A sustained study of the application of agricultural ecosystems is the only achievable way to develop an accurate vision on gas exchange between the atmosphere and terrestrial ecosystems (Beziat et al., 2009). Estimating carbon budget in agricultural ecosystems is an effective way to find out whether a given ecosystem is a source or a sink of carbon dioxide (Twine and Kucharik, 2009). The goal of this investigation was to study the effects of maintaining crop residues on CO2 flux and carbon balance in an agricultural system.
This study was conducted to investigate the effects of increased residue rate on the CO2 emission rate and determine the soil carbon budget in the presence or absence of residue in the soil surface. A randomized block design experiment including five treatments and three replications was carried out on a research farm of the University of Ferdowsi in 2011-12. Treatments include 0, 2, 4, 8 and 16 t ha-1 of wheat (Triticum aestivum L.) straw. The carbon budget was estimated in both years using a static closed chamber method according to analysis by gas chromatography (Shimizu et al., 2009).
Results showed that in spring and summer, soil temperature was higher than air temperature. In winter and autumn, air temperature was usually higher than bare soil temperature. In both the experimental years, the temperature of residue-containing soil was lower than that of the air in spring. The treatment with the highest residue rate (16 ton ha-1) had the lowest temperature in all measurements, however, the difference between various residue treatments was slight and the difference between 8 and 16 tons ha-1 was not significant in any measurement. Duiker and Lal (2000) showed that soil temperature under application of residue was 14˚c lower than bare soil. The daily CO2 emission rate ranged from 0.1 to 4.3 megagrams C ha-1year-1. The CO2 emission rate increased in line with increases in residue kept at the soil surface. The highest annual CO2 flux rate was obtained for 16 ton ha-1 residue as 3.7 in 2011 and 3.6 in 2012 and the lowest annual CO2 flux rate was gained in bare soil in the two experimental years as 0.7 and 0.9 tons ha-1. Based on this equation, annual CO2 flux was calculated. An exponential relationship between soil temperature and respiration has been also reported by other authors (Brar et al., 2013).
Residue application had a significant impact on soil temperature. The difference was large between unmulched and mulched treatments. Our results indicated a high correlation (> 85%) between soil temperature and CO2 flux which was positive and exponential. Although the total calculated CO2 flux from the bare soil treatment was lower than the other treatments, this treatment had a carbon budget more negative than the other treatments, which is an ecologically negative factor.

In the modernization of crop production, most methods used by growers to achieve better yields have largely been explored. Most of these methods involve increasing the efficiency of the utilization of natural resources. A rise in radiation use efficiency is one of the major criteria for obtaining a yield advantage. Plant dry matter accumulation has a linear relationship with accumulative Photosynthetically Active Radiation (PAR). Intercropping could be a strategy for increasing light absorption in agronomic systems and may improve radiation use efficiency (RUE): The additional solar energy used by the intercrop canopy leads to improved crop production and, thus, greater economic yield. Over the past three decades, there has been much study on the uses of radiation in intercropping and alley cropping systems for a wide range of crop combinations (Zhang et al., 2008; Sinclair and Muchow, 1999). However, the association of sesame and chickpea had not been analysed until now.
This study was conducted in order to evaluate radiation absorption and use efficiency in replacement series intercropping of chickpea and sesame. The treatments were arranged in split plots based on a randomized complete block design with three replications. The treatments consisted of two planting methods, namely row planting and mixed planting (as main plot) and five planting ratios including chickpea monoculture, sesame monoculture, 10% chickpea흍% sesame, 20% chickpea흍% sesame, 30% chickpea흍% sesame as sub plot.
Results showed that sesame RUE was higher than chickpea RUE in all the treatments. The amount of sesame RUE varied from 1.49 to 1.76 g MJ-1 PAR and from 1 to 1.27 g MJ-1 PAR in row planting and mixed planting, respectively. The amount of chickpea RUE, also varied from 1.02 to 1.1 g MJ-1 PAR and from 0.71 to 0.94 g MJ-1 PAR in row planting and mixed planting, respectively. The results also showed that sesame RUE in intercropping treatments was higher than in monocropping treatments, but chickpea RUE in intercropping treatments was higher than in simply monocropping in row planting. In general, the amount of RUE of both crops in row planting was higher than in mixed planting, either in intercropping or monocropping treatments. Based on these results the best recommendable treatment for intercropping is 100% sesame% chickpea based on row planting. The chickpea RUE for treatment of 100% sesame% chickpea based on row planting was the highest level (1.1 g MJ-1) among the other treatments and the sesame RUE of this treatment was higher than the sesame monocrop RUE (1.7 g MJ-1 vs. 1.49 g MJ-1 in monocrop). The main findings in this study were as follows: Firstly, the intercrop intercepted more PAR than sesame and chickpea alone. Secondly, sesame/chickpea intercropping utilized radiant energy more efficiency than the monocrop, and sesame alone had greater RUE than chickpea alone. The higher ratio of diffuse to direct radiation surrounding the intercrop peanut would help to improve its e value (Sinclair et al., 1999). The shading effect offered by the taller plant might be partially offset by its higher photosynthetic rates per unit PAR at low intensity (Sinclair et al., 1989, Tsubo et al., 2001).
The results showed that chickpea plants can tolerate the shade produced by sesame plants when grown as a row intercrop but not under mixed intercrop. The higher yields obtained in intercropping systems are probably due to greater radiation-use efficiencies. Chickpea RUE decreased under mixed cropping, for the reason that raised sesame produced shading on chickpea.

The aim of the present study is to determine the relationship of parent and peer attachment with positive and negative perfectionism and academic perform ance. The method of the present study is correlational method. The statistical population of this research was all first-year high school students enrolled in Elam in 1388-1387. The sample of this study is 360 first grade، male and high schools students in Ilam. Those students are chosen by means of a stage random sampling method. Participants completed Inventory of Parent and Peer Attachment (IPPA)، Inventory of Perfectionism at School، and Ahwaz Perfectionism Scale (APS). The statistical methods were used in this research، simple correlation and multivariate regression analysis method. The results showed significant relationship between studied variables. The results showed that attachment to mother is the best predictor of positive and negative perfectionism and academic performance، whereas attachment to father is the best predictor of academic performance. Also، the significance level of 0/01and 0/05 is considered.