mohsen jahan

Introduction: 

Pre-cultivated plants are types of plants that, after harvesting the economic part, the plant residuals are returned to the soil to increase the organic matter and to improve the next plant’s productivity. The use of plant residues can improve biological health by reducing the chemical inputs used in agriculture. Due to the fact that in dry areas such as North Khuzestan, the role of pre-cultivated plants and the effect of their residues on growth and performance have been studied less, this research can be done in different humidity conditions before planting the main plant, and the effects of plant residues and their role on the qualitative characteristics and organic matter of the soil and the performance of plants such as corn are promising and help farmers and researchers.

 This experiment was conducted in two neighboring farms. In each year, two experiments were conducted in a randomized complete block design with four replications in two years and two locations. Before planting corn in two fields, cultivation treatments and mixing residues of four plant species, including rice, cowpea, dill, eggplant, and fallow, were used as experimental treatments. After harvesting the pre-cultivation plant, investigate the effect of plant residues on some soil characteristics over time. In order to determine the amount of moisture stored in the soil, in two stages before planting and in the middle of the corn growing season, the percentage of soil moisture by weight was calculated. To determine the organic carbon content in the soil before planting and during the mid-growth stage of the corn plant, organic carbon was oxidized using potassium dichromate in the presence of concentrated sulfuric acid, followed by titration with semi-normal ammonium ferrous sulfate in the presence of the ortho phenanthroline reagent (Walkley, 1934). Additionally, soil nitrogen was measured in the laboratory using the Kjeldahl method (Pag et al., 1982).

In both farms, the stability of the soil grains in the second year was higher than in the first year, which is due to the placement of organic materials of plant residues in the structure of the soil grains (Koocheki et al., 2020). Soil stability increased in both farms in the second year, with the difference that the soil stability increased by 64% in WET Planting and 50% in dry Planting. In the first and second years, respectively, there was a 35 and 29% increase in soil moisture compared to the control. The results of this research showed that the positive effect of plant residues in improving the organic matter of the soil after corn cultivation in wet Planting was much higher than that of dry Planting. The rice residues increased the soil organic matter by 51 and 47% in wet Planting and dry Planting. The results of the measurement data before corn cultivation showed a significant increase in the amount of nitrogen in the soil in the second year, and this increase was 55% higher in the field with the method of wet Planting cultivation. The results of the measured data after corn cultivation in the second year showed that the amount of nitrogen in the soil increased, and the intensity of the increase in the field using the wet Planting method was 44% more than the field using the dry method.

 The results of this experiment showed that the apparent specific weight of the soil in the second year, influenced by the use of plant residues, decreased over time. The preservation of plant residues has caused an increase in the amount of nitrogen in the soil, and in wet planting conditions, the intensity of its increase has been 44% more than in DRY Planting conditions. Also, by using plant residues of dill and beans, the amount of phosphorus in the soil increased.

Among the approaches that have received attention in recent years to sustain agroecosystems is the identification and employment of traditional/indigenous/local knowledge and strategies of smallholder farmers around the world to solve the basic challenges of these ecosystems regarding food production. In this regard, the role and function of biodiversity as the main component of indigenous knowledge is of particular importance. At the same time, with the expansion of new agricultural solutions, the use of these farmers' approaches has decreased over time and, in some cases, has completely disappeared. Therefore, this study was conducted with the aim of identifying the indigenous methods used in the agricultural ecosystems of the Sabzevar region and their role in increasing biodiversity. Biodiversity loss has been a major concern to humans, especially during the last quarter of the previous century. Nowadays, various efforts to protect agricultural biodiversity are emerging that seem not enough. Biodiversity in agricultural ecosystems causes effective control of weeds, pests and diseases and greater resistance to changing environmental conditions and leads to better management of agricultural systems and increased food security. Additionally, biodiversity is carefully managed and nurtured to interface with hydrological and nutrient cycling to provide for ecosystem resilience, food security and diversity, and risk minimization. Although potentially less important in the short term, biodiversity, encompassing variation from within species to across landscapes, may be crucial for the longer-term resilience of ecosystem functions and the services that they underpin. Accordingly, in this research, the methods employed by local farmers to increase biodiversity were investigated.
In order to evaluate the usefulness of indigenous knowledge for assessing trends in biodiversity, a case study was undertaken in two counties, Sheshtamad and Sabzevar, in Razavi Khorasan province. This involved the use of participatory rural appraisal (PRA) techniques, including semi-structured interviews and transect walks. To study local methods employed by farmers, 453 farmers were interviewed and questions were asked to the farmers about the number of crop species and the amount of use of methods to increase biodiversity such as rotation, fallow, mixed cropping, etc.
The results showed that agricultural systems in these areas have shifted from livelihood systems to market-based systems. Local farmers in these areas used a variety of methods such as using different crops from different families, intercropping, rotation, fallow, seed exchange, integration of livestock with cropping and horticulture to increase diversity in their farms. The main common products in these two cities were plants such as wheat, barley, cotton, alfalfa and pistachios. Most of the plants used in the cultivation pattern of farmers in these cities were related to plant families such as Poaceae, Fabaceae, Malvaceae, Asteraceae, Cucurbitaceae, Amaranthaceae and Rosaceae, which had a different contribution in the cultivation pattern of the studied villages. There was a significant difference between the villages, districts and two counties in terms of the plant species and plant families used. In all the studied villages, farmers employed more than one method to increase the diversity of their farms. The fosterage of livestock and horticulture plus to cropping in these agroecosystems led to greater economic security for farmers, in particular in adverse weather conditions. In general, the results showed that rural development has led to a reduction in the use of traditional knowledge/local methods only in limited cases, and the employing of local methods in some cases has increased the net income of farmers from wheat farming systems.
The results approved that the farmers in these areas used different crops from different families and groups and also used methods such as intercropping, rotation, integration of livestock with cropping, fallow and seed exchange to increase the biodiversity in the three levels of species, function and ecosystem in the agroecosystems of these regions. Increasing biodiversity in agroecosystems is very important and significant issue, especially in arid and semiarid areas, because improved biodiversity in these areas can increase food and economic security to some extent. Diversification could become an essential tool for sustaining production and ecosystem services in croplands, rangelands and production forests.

Climate change is rapidly degrading the conditions of crop production. For instance, increasing salinization and aridity is forecasted to increase in the most parts of the world. This research was conducted in two regions of Yazd province with 10 separate experiments in the form of a randomized complete block design with three replications. Experimental factors included 5 promising modified lines in Yazd Salinity Research Center with Titicaca cultivar.The results of calibration and validation of CROPGRO model with DSSAT software were evaluated as favorable for quinoa and the 30-year seasonal analysis of the model for the city of Yazd showed that the optimal planting dates for lines 3, 4, 5 and 6 are the first of August, the end of July, and the middle of It is August and the end of July because it is the shortest period of growth. Considering that this model can integrate the complex interactions of soil properties, climatic conditions, management practices and genetic characteristics of the product, it leads to a better understanding of the complex interactions between factors affecting the growth and development of this plant, so it can be used to develop studies on the aspect Different types of quinoa ecophysiology should be used in research departments.

The length of the growth period is the key to crop adaptation to new environments. It is strongly affected by the environment in such a way that it is possible to predict the length of the growing period based on some correlations with environmental factors. Simple models that quantify intraspecific variability in flowering responses to temperature and photoperiod can be useful for characterizing lines. Quinoa (Chenopodium quinoa) shows considerable resistance to a wide range of abiotic stresses. Cardinal temperatures and day length at each development stage are necessary to find an appropriate model for predicting plant growth and development.

Ten separate experiments (10 planting dates included: 29 March, 29 April, 28 May, 28 June, 26 July, 23 August, 6 September, 20 September, 29 January, and 29 February) were conducted as randomized complete block design with three replications. The experimental factor consisted of five quinoa lines plus one cultivar (Titikaka). Five promising lines were modified at Yazd Salinity Research Center. Four lines belong to the middle maturing group, one to the late maturing group, and the Titikaka cultivar belongs to early maturing group. The time of beginning and end of each developmental stage, including germination, pollination, and seed maturity, was recorded. The response of developmental stages to temperature and photoperiod was used to determine the cardinal temperature and day length of the main developmental stages (emergence, flowering, and seed maturity).

Based on the coefficient of determination (R2) it seems that the quadratic model is suitable for estimating the cardinal temperatures of germination, flowering, and ripening of quinoa seeds. Using both quadratic and segmented models to estimate the length of special days resulted to satisfactory robustness. The results showed that on days with a length of lesser than 12 hours and temperatures lesser than 30°C, the flowering rate increased with a simultaneous increase of temperature and day length. As the day length increased to 14 hours, the rate of flowering development changed more significantly when temperatures were between 19 and 25°C than at temperatures below 19°C. For all lines, increasing the day length or temperature resulting in an increased plant maturation rate (from flowering to seed maturity) at a constant temperature or day length. The optimal temperature range for all developmental stages of quinoa lines was between 20 and 25°C. There was a significant difference in the base temperatures of the developmental stages. The base temperature for germination of quinoa lines was above 0°C, the base temperature for flowering was between -2 and +2°C, and the base temperature for seed maturity was below 0°C. The maximum temperature of all quinoa developmental stages was above 40°C (42-51°C). At low temperatures, the flowering stage was more sensitive than the seed ripening stage. The critical day length for flowering and seed ripening of quinoa lines was between 11.5 to 12 hours.

The optimum temperature range for germination was obtained by 25-34°C, for flowering by 28-21°C, and for seed ripening by15-32°C. The optimum temperature of all developmental stages of quinoa lines was between 20 and 25°C. The optimum day length range for flowering is estimated at 11.37-34.12 hours and for seed ripening by 10.58-12.3 hours. Using the segmented and quadratic models to estimate quinoa cardinal temperature and photoperiod response resulted in the same estimations, although in most values, the quadratic model showed a higher coefficient of determination. In general, the results indicated that the temperature and day length have a compensatory effect on the flowering rate and seed ripening stages of the studied lines.

Water stress is one of the most important factors in reducing the yield of agricultural products worldwide. If the stress is intensive and continuous, plant growth and productivity are severely diminished. Water superabsorbent polymer can absorb and retain extremely large amounts of a liquid relative to its own mass. They have a wide range of applications because of their high water absorbing capacity, biodegradability and low cost.Humic acid is an organic compound that is derived from the decomposition of organic matter and contains carbon, hydrogen, oxygen and nitrogen. This acid plays a key role in increasing the fertility of the soil and feeding the plant when added to the plant, in helps to increase its growth through its effect to photosynthesis, respiration, increase the plants resistance to harsh environmental conditions and stimulates many of the vital interactions within the plant.Salicylic acid, a naturally occurring plant hormone, acts as an important signaling molecule and enhances tolerance of treated plants against biotic stresses. Salicylic acid also has a vital role in plant growth, ion uptake, and nutrient transport within the plant.Factor analysis is a technique that is used to reduce a large number of variables into fewer numbers of factors. This technique extracts maximum common variance from all variables and puts them into a common score.

In order to evaluate the effects of different irrigation levels and nutritional treatments and determining factors affecting water use efficiency of maize (Zea mays L.), a split plots experiment based on RCBD design with three replications was conducted during 2015-16 growing season, at Research Field of Ferdowsi University of Mashhad, Iran. Irrigation levels in two levels (50 and 100% of water requirement) and nutritional treatments in five levels (1- Nitrogen+Superabsorbent, 2- Superabsorbent+Humic acid+Salicylic acid, 3- Humic acid+Salicylic acid+Nitrogen, 4- Humic acid+ Salicylic acid+Nitrogen+Superabsorbent and 5- Control) assigned to main and sub plots, respectively.

The results showed that all of the nutritional treatments affected water use efficiency, but in both conditions of 50 and 100% of water requirement, the highest water use efficiency were obtained in treatment of Humic acid+Salicylic acid+Nitrogen+Superabsorbent. The highest seed yield (17542 kg.ha-1) observed in treatment of nitrogen+superabsorbent+humic acid+Salicylic acid and supply 100% of water requirement and the lowest seed yield (12515 kg.ha-1) obtained in treatment of control and supply 50% of water requirement. Factor analysis results showed that variables analyzed to two factors. First factor included 51% of variables variance, respectively. First factor included variables of seed yield, biological yield, plant height, leaf area index, crop growth rate and soil nitrogen, phosphorous and pH and variables of seed weight per plant, soil EC and water use efficiency were in second factor. In first factor, important variables such as soil nitrogen, phosphorous were included, so this factor describe soil conditions and second factor which had the highest impact on water use efficiency was called as water use efficiency factor. In a research reported that application of water superabsorbent increased seed yield of maize compared to control. In another research, the highest seed yield of maize obtained in treatment of simultaneous application of 120 kg.ha-1 water superabsorbent and 8 kg.ha-1 humic acid. Application of salicylic acid and humic acid enhanced seed yield of maize 24.5 and 24.2% compared to control, respectively.

In general, based on results of this research, it seems simultaneous application of nitrogen and ecological inputs can improve yield, growth characteristics and water use efficiency. Factor analysis and high correlation among variables in same group showed that with change of variables that are in same group of water use efficiency, can increased water use efficiency and decreased damages of drought stress.

Common bean (Phaseolus vulgaris L.) is the world’s most important food legume crop. This staple considered as a nearly perfect food mainly because of its high protein content (about 25 percent) and abundant fiber, complex carbohydrates (about 60 percent), and other daily food needs such as vitamins (folate) and minerals (Cu, Ca, Fe, Mg, Mn, and Zn). Water use in agricultural production as one of the most important environmental factors affecting plant growth and development, especially in arid and semi-arid climatic conditions of Iran. 

In order to study the effect of plant growth promoting Rhizobacteria and nitrogen chemical fertilizer on some characteristics of root and growth indices of bean (Phaseolus vulgaris L.) under water stress conditions, a split-plot design based on RCBD with three replications was conducted during growing season of 2015-16 at Agricultural Research station, College of Agriculture, Ferdowsi University of Mashhad, Iran. Three levels of irrigation (100%, 75%, 50% water requirement) assigned to main plots and different types of biofertilizers (Nitroxin®, containing Azotobacter sp. and Azospirillum sp., Biophosphor®. containing Phosphate-solubilizing bacteria Bacillus sp. and Pseudomonas sp.), Nitrogen fertilizer) urea form, and Control (no fertilizer) were assigned to sub plots. Destructive sampling was performed to calculate the growth indices (such as TDW (total dry weight), LAI (leaf area index), CGR (crop growth rate), RGR (relative growth rate) and NAR (net assimilation rate)) randomly from competing plants regarding the marginal effects from 1 real completed leaf stage to the end of the growing season from 5 m2 surface (every 7 days; 12 steps). The growth indices of LAI, CGR, RGR and NAR were calculated using equations (1-4). At the end of the growing season SRL (specific root length) was determined by Tenant Modified Method. Leaf area calculated by Leaf Area Meter device (Delta T, UK). Data analysis of variance and figures preparation were done by Minitab Ver. 16, Slide Write Ver. 2, and Excel 2010 softwares. At the end, Means comparing did by Duncan's test at probability 5%.
 
Equation 1:LAI= (1/GA)[(LA2+LA1)/2]                                                                           
Equation 2:CGR= (1/GA)[(W2–W1)/(t2–t1)]                                                                                
Equation 3:RGR= (lnW2–lnW1)/(t2–t1)                                                                            
Equation 4:NAR= [(W2–W1)/(t2–t1)] [(lnLA2–lnLA1)/(LA2–LA1)]                                 
where GA is ground area (m2), LA is leaf area (m2), W is shoot dry weigh (g) and t is time (day).

According to the result, the effect of biological fertilizers especially Nitroxin significantly increased maximum values of bean`s growth indices included total dry matter (TDM max), leaf area index (LAI max), crop growth rate (CGR max), relative growth rate (RGR max) and net assimilation rate (NAR max) compared to control and even nitrogen fertilizer. So that the highest and the lowest total dry matter (TDM max) at 91 days after planting were observed in Nitroxin (370 g.m-2) and control (342 g.m-2) traits (p≤0.01), respectively. The highest and the lowest leaf area index (LAI max) at 91 days after planting were observed in Nitroxin (2.0) and control (1.7) traits (p≤0.01), respectively. The highest and the lowest crop growth rate (CGR max) at 77 days after planting was observed in Nitroxin 11.04 g.m-2.day-1 and control 8.81 g.m-2.day-1 traits (p≤0.05), respectively. The highest and the lowest relative growth rate (RGR max) at 21 days after planting was observed in Nitroxin 0.23 g.g-1.day-1 and control 0.20 g.g-1.day-1 traits (p≤0.01), respectively, and then decreased gradually. Similar to RGR, the highest and the lowest net assimilation rate (NAR max) at 21 day after planting was observed in Nitroxin 35.5 g.m-2.day-1 and control 28.4 g.m-2.day-1 traits (p≤0.05), respectively. All attributes, showed highest values at 100% water requirement treatment. Also, the effect of fertilizers (p≤0.05) and water requirement (p≤0.01) were significant on grain yield. The main and interaction effects of fertilizer and irrigation were significant (p≤0.05) on specific root length (SRL). So that, the highest specific root length (30.15 m.25cm-3 soil) were obtained from Nitroxin and 100% water requirement. 

In total, the results showed that it could be possible to produce the healthy production of bean, moreover, attain the optimum yield as equal as to conventional systems.

An experiment based on CRD design with three replications was conducted in 2014 year, in Ferdowsi University of Mashhad, Iran. The experimental treatments included 7 types of eco-friendly inputs: Humic acid, Fulvic acid, Nitroxin (contains Azotobacter spp. And Azospirillum spp. Bacterias), Biophosphorous (contains Bacillus sp. And Pseudomonas sp. bacterias), Biosulfur (contains Thiobacillus spp. Bacteria), Glomus mosseae, Glomus intraradices, and control. The results showed that organic acids of humic and fulvic increased germination percentage 25 and 20% and germination rate 58 and 33% compared to control, respectively. Germination percentage was 20, 25, and 24% more in biofertilizers of nitroxin, biophosphorous and biosulfur compared to control, respectively and germination rate under application of this fertilizers added 59, 24, and 50% compared to control, respectively. Humic acid, fulvic acid, nitroxin, biophosphorous, biosulfur, Glomus mosseae and Glomus intraradices reduced mean germination time 33, 35, 38, 19, 36, 36, and 16% compared to control, respectively. The highest radicle and plumule length obtained in treatment of humic acid and the highest radicle to plumule length observed in treatment of biosulfur. Fulvic acid increased radicle and plumule dry weight 51 and 38% compared to control, respectively. The highest and the lowest radicle to plumule dry weight obtained in treatments of Glomus intraradices (0.199) and control (0.124), respectively.

The use of cultivated plants in the consecutive of cropping systems is one of the most important alternative and sustainable methods to eliminate or reduce the use of herbicides. To investigate the effect of crop residues on weed control and corn yield of NS640 cultivar, an experiment was conducted in 2015-2016 and 2016-2017 cropping years. This experiment was performed in two years and two places in a randomized complete block design with four replications. Two farms with clay- loamy and sandy-loam soil as a place and cultivation of four pre-corn crops including bean-branch (Vicia faba L.), wheat-Chamran (Triticum aestivum L.), rapeseed-Hayula 401 (Brassica napus L.), cabbage - Steady hybrids (Brassica oleraceae L.) and fallow were the treatments. Combined analysis of the results showed that the comparison of weed density and dry weight in different treatments of pre-cultivated plants with fallow (without pre-cultivated plants) showed the potential of pre-cultivated plant residues in reducing and controlling weeds. The reduction in the number of weeds in clay-loam field in the residues of bean, wheat, rapeseed and cabbage pre-cultivation plants compared to fallow were 22, 9, 10 and 29%, respectively, and in sandy-loam field 40, 48, 42 and 46%, respectively. Weed dry weight was significantly affected by crop residues. Bean, wheat, canola and cabbage residues reduced weed dry weight by 54, 55, 43 and 65% compared to fallow, respectively. The use of bean residues as a growing crop in clay-loamy and sandy-loam soils increased corn seed yield by 40 and 55%, respectively. The use of crop residues by higher decomposition of crop residues in the second year and creating a state of soil damage and a negative effect on weed dynamics indices can play an effective role in improving corn growth and increasing the productivity of the cultivation system.

In order to evaluate effect of water superabsorbent application on yield and some physiological characteristics and water productivity of common bean (Phaseolus vulgaris L.), sesame (Sesamum indicum L.) and maize (Zea mays L.) in water stress conditions, a split plots experiment based on RCBD design with three replications was conducted during 2015-2016 growing season, in Research Farm of Ferdowsi University of Mashhad, Iran. Irrigation levels (50 and 100 percent of water requirement) and application (80 kg.ha-1) and non-application of water superabsorbent assigned to main and sub plots, respectively. The results showed that in bean, the highest seed yield (2191kg.ha-1), dry matter yield (4588 kg.ha-1), weight seed per plant (10.89 g), height plant (97 cm), LAI (9.39), CGR (8.35 g.m-2.day-1), soil nitrogen (0.163%), phosphorous (0.0082%) and pH (9.68) obtained in treatment of 100 percent of water requirement and application of water superabsorbent. In sesame, application of water superabsorbent in drought stress conditions (50 percent of water requirement) increased seed weight per plant (22.17 g), plant height (91 cm), LAI (9.70), CGR (6.58 g.m-2.day-1) and soil nitrogen (0.101%), phosphorous (0.0063%) and pH (9.32) by 24, 30, 32, 59, 20, 44 and 17 percent compared to control, respectively. In maize, the highest seed yield (22522 kg.ha-1), dry matter yield (39502 kg.ha-1), seed weight per plant (332 g), plant height (194 cm), LAI (8.10), CGR (9.43 g.m-2.day-1) and soil nitrogen (0.095%) and pH (9.70) observed in treatment of 100 percent of water requirement and application of water superabsorbent.

The nitrogen budget or balance is often evaluated by comparing various nitrogen inputs and outputs in soil–crop systems. Research on nitrogen balance can provide more detailed information on the nitrogen cycle and its losses by integrating soil nitrogen processes with the total nitrogen budgets. There are restricted researches for evaluation of nitrogen balances in the cropping systems. It is clear that accurate measuring of each component of nitrogen budgets in relation to soil processes is difficult. Wheat (Triticum aestivum L.) is the main cereal crop cultivated in Iran. According to published data the average nitrogen application rates in wheat cropping systems of Iran is 120 kg.ha-1 but, the excessive use of fertilizer nitrogen is very common in wheat fields. It is estimated that in Iran, about 2.2 million ha of wheat production areas are under irrigation. Alike, there are limited studies on nitrogen dynamics, budgets and its losses pathways in wheat production systems of Iran. Such studies are essential to understand the nitrogen behavior and balance in wheat cropping systems. This research was carried out with the aim of evaluating nitrogen balance of wheat cropping systems with different climatic conditions over the country by using CENTURY model.

We used CENTURY model (Parton et al., 1994) to evaluate nitrogen dynamics and nitrogen balance in wheat cropping systems. For this purpose 14 wheat cropping system located in diverse climates were selected. Soil data was collected from Soil and Water Research Institute and weather data from 2000 to 2014 were obtained from Iran Meteorological Organization for 14 selected stations. The CENTURY model simulates the long-term dynamics of Carbon (C) and Nitrogen (N), for different Plant-Soil Systems. The model can simulate the dynamics of agricultural crop systems. The crop system of CENTURY have different plant production sub-models which are linked to a common soil organic matter sub-model .The soil organic matter sub-model simulates the flow of C, N through plant litter and the different inorganic and organic pools in the soil. CENTURY model runs in monthly time step with monthly precipitation (cm), monthly mean minimum and maximum temperature (°C), site latitude and longitude, sand, silt and clay (%), soil bulk density (g.cm-3), rooting depth (cm), C and N content of the top 20 cm of soil and management information such as planting date, first and last month of wheat growth, number and amounts of applied fertilizers, amount of irrigation water and its schedules are required. For model validation we used two statistical measures including Normalized Root Mean Squared Error (nRMSE), Willmott (1982) index of agreement (d value) and linear regression coefficients between actual and predicted values.

Results revealed that the highest nitrogen input in wheat cropping systems (9.5 - 12.5 g.m-2) was observed in Northwest, West and Southwest and the lowest (7.3 - 9.4 g.m-2) were in East and Southeast areas of the country. Also, nitrogen output plan in wheat cropping systems was similar to nitrogen input. In addition, stepwise regression analysis indicated that fertilizer application rate with partial coefficient of 97.33% and grain nitrogen with partial coefficient of 92.79%, respectively, were the most important variables in relation to nitrogen input and output in wheat cropping systems of Iran.

According to the results, it seems that in relation to nitrogen input, the role of agronomic management such as fertilizer application, coincidence of fertilizer application time with plant requirement and increasing nitrogen use efficiency (NUE) which is mostly dependent on agricultural management are important issues. But in the case of nitrogen outputs from wheat cropping systems, in addition to agronomic managements, use of improved cultivars with higher nitrogen uptake efficiency is more important.

Today, more than a third of the worlds land is located in arid and semi-arid areas that are subject to water constrains. Drought stress causes different physiological changes in the plant, such as increasing shading temperature, increasing concentration of proline amino acid, decreasing leaf relative humidity, increasing soluble sugars concentration, increasing stomatal resistance and increasing concentration of antioxidant compounds of plant. Considering the destructive effects of drought stress, in recent years, many efforts have been made to increase water use efficiency. The use of superabsorbents and spraying of humic acid and salicylic acid are considered as essential solutions for saving and optimizing water use. Regarding insufficient water availability in the country and the importance of using ecofriendly inputs in increasing water productivity and conducting few studies on the use of statistical techniques to identify the factors affecting water use efficiency, this research in order to investigate the effect of water superabsorbent, humic acid and salicylic acid on water use efficiency and some morphological characteristics and yield and tolerance indicators of bean (Phaseolous vulgaris L.) under drought stress was done.

In order to determine factors affecting water use efficiencis of common bean (Derakhshan cultivar) affected by different inputs in conditions of drought stress, a split plot experiment based on RCBD design with three replications was used during 2015-16 growing season, at Research Farm of Ferdowsi University of Mashhad, Iran. Irrigation levels (50 and 100% of water requirement) and nutritional treatments (75 kg.ha-1 Nitrogen+80 kg.ha-1 Superabsorbent, 80 kg.ha-1 Superabsorbent+6 kg.ha-1 Humic acid+1 Mm Salicylic acid, 6 kg.ha-1 Humic acid+1 Mm Salicylic acid+75 kg.ha-1 Nitrogen, 6 kg.ha-1 Humic acid+1 Mm Salicylic acid+75 kg.ha-1 Nitrogen+80 kg.ha-1 Superabsorbent and Control) assigned to the main and sub plots, respectively. In this research, traits shuch as seed yield, dry matter yield, harvest index, weight seed per plant, height plant, LAI, CGR, soil nitrogen, phosphorous, EC and pH was estimated.

The result showed that all of the nutritional treatments had significantly effects on water use efficiency, but in both conditions of 50 and 100% of water requirement, the highest water use efficiency were obtained in Humic acid+Salicylic acid+Nitrogen+Superabsorbent, so that this treatment increased water use efficiency 63 and 55% compared to control in 50 and 100% of water requirement, respectively. All of the nutritional treatments decreased damages caused by drought stress, but in this conditions (50% of water requirement), the highest LAI (7.24), CGR (6.47 g.m-2.day-1), soil nitrogen (0.32%) and phosphorous (0.0183%) observed in treatment of nitrogen+superabsorbent+humic acid+salicylic acid. Application of nitrogen+superabsorbent, superabsorbent+humic acid+salicylic acid, nitrogen+humic acid+salicylic acid and nitrogen+superabsorbent+humic acid+salicylic acid increased mean productivity (MP) 19, 54 and 47 and 59%, geometric mean productivity (GMP) 18, 55 and 48 and 59% and harmonic mean (HM) 17, 55 and 48 and 60% compared to control, respectively. Effect of nutritional treatments on stress susceptibility (SSI) and stress tolerance index (STI) was significant and the lowest SSI (0.59) and the highest STI (1.51) obtained in treatment of nitrogen+superabsorbent+humic acid+salicylic acid.

In general, the results showed that although all nutritional treatments were effective in reducing drought stress damages, but the highest seed yield, dry matter yield, harvest index, weight seed per plant, leaf area index, crop growth rate, soil nitrogen and water use efficiency observed in treatment of nitrogen+superabsorbent+humic acid+salicylic acid. MP, GMP and HM in all nutritional treatments was more than control, significantly. Application of superabsorbent+humic acid and salicylic acid, nitrogen+humic acid+salicylic acid, nitrogen+superabsorbent+humic acid+salicylic acid decrease SSI compared to control and the highest STI obtained in treatment of nitrogen+superabsorbent+humic acid+salicylic acid.

Due to the importance of Iranian Ox-Tongue (Echium amoenum) as one of the most important pharmaceutical products used in many pharmaceutical, cosmetic and health industries, this study was done for simultaneous evaluation the effect of planting date and method and different biological and chemical fertilizers on some phytochemical characteristics of Iranian Ox-Tongue in Mashhad conditions.  

A split split plots experiment based on RCBD design with three replications was conducted in 2011-2013 growing seasons, in Ferdowsi University of Mashhad, Iran. Two different planting dates (10 March 2011 and 4 April 2011), three different types of biofertilizers and chemical fertilizers, as mycorrhiza (Glomus mosseae), biosulfur, chemical fertilizer and control and two different types of planting methods (direct seeding and transplanting) assigned to main plots, sub plots and sub-sub plots, respectively.  

The results showed that the highest dry flower yield obtained in conditions of mycorrhiza application in March planting date and direct seeding. Application of mycorrhiza, biosulfur and chemical fertilizer in conditions of transplanting and March planting date increased seed yield 45, 42 and 35%, respectively. In April planting date antioxidant activity in direct seeding was more than transplanting. Application of mycorrhiza and biosulfur increased antioxidant activity 18 and 35% in direct seeding and 20 and 18% in transplanting compared to control, respectively. Mycorrhiza in April planting date increased total anthocyanin 28 and 27% in direct seeding and transplanting compared to control, respectively.  

In general, according to the results of this research, the planting method of direct seeding in March and application of ecological inputs of mycorrhiza and biosulfur is recommended to improve the yield and qualitative characteristics of Iranian Ox-Tongue.

In order to evaluate effect of deficit irrigation and application of water superabsorbent and determining principal components in water use efficiency of common bean, sesame and maize a split plots experiment based on RCBD design with three replications was conducted during 2015-2016 growing season, in Ferdowsi University of Mashhad, Iran. Irrigation levels (50 and 100% of water requirement) and application and non-application of water superabsorbent assigned to main and sub plots, respectively. Principal components analysis for three plant species resulted in two principle components with the most considerable variances. The first component explained 73, 60 and 80% of variables variance in bean, sesame and corn, respectively. In bean, variables of seed yield, biological yield, seed weight, plant height, crop growth rate and soil nitrogen, phosphorous content and pH were assigned to the first component and leaf area index, EC and water use efficiency were assigned to the second component. In sesame, variables of seed yield, biological yield, seed weight, plant height, crop growth rate and soil phosphorous and pH had the highest load on the first component and variables of leaf area index, soil nitrogen content, EC and water use efficiency had the highest load on the second component. In corn, variables of seed yield, biological yield, seed weight, plant height, leaf area index, crop growth rate and soil nitrogen and pH were in the first component and variables of soil phosphorous and EC and water use efficiency in the second component had the highest load.

To investigate the effects of the residues of pre-cultivated plants on the physical and chemical properties of two types of soils and maize yield in the north of Khuzestan, an experiment was carried out at experimental farm of Shuster Faculty of Agriculture during2014-15and2014-15.Two field experiments were performed in two years and two locations in a randomized complete block design data were subjected to combined analysis. The maize was cultivated in fields with these crop residues for two years, and then, soil properties, growth and yield characteristics of maize were studied. Measured values for such traits in sandy Loam soil were greater than clay Loam soil. The residues of pre-cultivated plants including beans, wheat, rapeseed and cabbage caused pH of soil by2%,3%,2% and 2% showed significant reduce compared to, respectively. Using residue of per-cultivated plants resulted in increased aggregate stability, organic matter, soil moisture, organic carbon, total amounts of nitrogen, potassium and phosphorus by50%,49%,40%,33%,22%,24% and70%, respectively, and this increase was remarkable in sandy Loam soil. The results of this study clearly indicated that the use of the crop residues of pre-cultivated plants in field increased growth, yield and yield components, and in this regard, the bean residues were more useful than other plants.

Insufficient access to water in arid and semi-arid areas has considered water use efficiency as one of the main pillars of sustainable agriculture in these areas. Therefore, in recent years, many efforts have been done to increase water use efficiency, in this regard, the use of superabsorbents and spraying of ecological inputs such as humic acid and salicylic acid are considered as fundamental solutions for saving and optimizing water usage, therefore, this research was conducted with the aim of using factor analysis to determine the affecting factors on water use efficiency of sesame in the conditions of simultaneous application of nitrogen and ecofriendly inputs.

In order to evaluate the effects of different irrigation levels and nutritional treatments and determining factors affecting water use efficiencis of common bean (Phaseolus vulgaris L.), sesame (Sesamum indicum L.) and maize (Zea mays L.) a split plots experiment based on RCBD design with three replications was conducted during 2015-16 growing season, at Research Farm of Ferdowsi University of Mashhad, Iran. Irrigation levels (50 and 100% of water requirement) and nutritional treatments (1- 75 kg.ha-1 Nitrogen+80 kg.ha-1 Superabsorbent, 2- 80 kg.ha-1 Superabsorbent+6 kg.ha-1 Humic acid+1 Mm Salicylic acid, 3- 6 kg.ha-1 Humic acid+1 Mm Salicylic acid+75 kg.ha-1 Nitrogen, 4- 6 kg.ha-1 Humic acid+1 Mm Salicylic acid+75 kg.ha-1 Nitrogen+80 kg.ha-1 Superabsorbent and 5- Control) assigned to main and sub plots, respectively.

The results showed that the highest seed yield (1672 kg.ha-1) obtained in 100% of water requirement and application of nitrogen+superabsorbent+humic acid+salicylic acid. The role of humic acid and salicylic acid in improving most of the studied traits was significant, so that seed yield, leaf area index, crop growth rate and water use efficiency were 22, 31, 30 and 21% more than treatments without the two inputs, respectively. Factor analysis results showed that variables analyzed to two factors. First factor 59 of variables variance, respectively. First factor included variables of seed yield, seed weight per ,plant, crop growth rate, soil nitrogen and phosphorous and water use efficiency and variables of dry matter yield, plant height, leaf erea index and soil pH were assigned in second factor.

In general, the results of this research showed that treatments of nitrogen+superabsorbent, superabsorbent+humic acid+salicylic acid, nitrogen+humic acid+salicylic acid and nitrogen+superabsorbent+humic acid+salicylic acid increased water use efficiency 15, 27, 32 and 40% compared to control, respectively. According to the results of factor analysis and variables belonging to each factor, it seems that the first factor is the index of yield and the second factor reflects the inherent characteristics of the spatial arrangement of the plant (high load of plant height and leaf area index on this factor). In general, it seems simultaneous application of nitrogen and ecological inputs can improve yield, growth characteristics and water use efficiency. Factor analysis and high correlation between variables in same group showed that with change of variables that are in same group of water use efficiency, can increased water use efficiency and decreased damages of drought stress.

In recent years, by minimizing the use of chemical fertilizers and replacing them with biological fertilizers has become important as one of the key principles of sustainable agriculture. Common bean (Phaseolus vulgaris L.) is the world’s most important food legume. This staple considered as a nearly perfect food mainly because of its high protein content and abundant fiber, complex carbohydrates, and other daily food needs such as vitamins (folate) and minerals (Cu, Ca, Fe, Mg, Mn, and Zn). Water used in agricultural production as one of the most important environmental factors affecting plant growth and development, especially in arid and semi-arid climatic conditions of Iran is of special importance. Since biological facility for production increase in agriculture is use of terrestrial useful living tiny, that cause is becoming plant yield and growth increase.

In order to study the effect of plant growth promoting Rhizobacteria and nitrogen chemical fertilizer on yield and yield component of bean (Phaseolus vulgaris L.) under water stress conditions, a split-plot design based on RCBD with three replications was conducted at Agricultural Research Station, College of Agriculture, Ferdowsi University of Mashhad, Iran in 2015. Three levels of irrigation (to supply of 100, 75, and 50 percent water requirement) were assigned to main plots and different types of biofertilizers (1- Nitroxin, containing Azotobacter sp. & Azospirillum sp. as inoculation seed, 2- Biophosphor, containing Phosphate-solubilizing bacteria Bacillus sp. & Pseudomonas sp.) as inoculation seed, 3- Nitrogen chemical fertilizer (100 kg.ha-1 urea form), and 4- Control (no fertilizer) were assigned to sub plots. Irrigation levels according to irrigation requirements in each irrigation period were carried out by water meter device. The growth index of LAI (leaf area index) was determined randomly from 5 competing plants regarding the marginal effects from 1 real completed leaf stage to the end of the growing season (every 7 days; 12 steps). LAI index was calculated using equation (1). Leaf area was calculated by Leaf Area Meter device (Delta T, UK). At the end of growing season, yield and yield component were determined regarding the marginal effects from 5 m2 surfaces. Data analysis of variance and draw charts were done by Minitab Ver. 16, Slide Write Ver. 2, and Excel 2010 softwares. At the end, Means comparing did by Duncan's test at probability 5 percent.LAI= (1/GA) [(LA2+LA1)/2] (Equation 1)Where GA is ground area (m2), LA is leaf area (m2).

According to the result, the effect of fertilizers was significant (P≤0.05) on grain yield, and number of pod per plant, and was very significant (P≤0.01) on number of seeds per pod, and 100 seed weight. Among these fertilizers, Nitroxin fertilizer had the highest effect on traits and was increased these compare to control 92.4, 101.7, 47.3 and 38.7 percent, respectively. Also the effect of irrigation levels on all of traits was very significant (P≤0.01). So that the lowest of traits were observed in 50 percent water requirement of bean and compare to 100 percent water requirement were decreased 68.1, 35.8, 56.3 and 38.1 percent, respectively. Interaction of fertilizer and irrigation was significant (P≤0.05) only on dry matter yield of bean, so that the highest and the lowest of dry matter yield were obtained from Nitroxin+100% water requirement (7741 kg.ha-1) and Control+50% water requirement (880 kg.ha-1), respectively. In general, the results of this experiment declared that there was no significant difference between using of Biophosphor and nitrogen chemical fertilizer concerning the effect on bean traits including: seed yield, pod no. per plant, seed no. per pod, 100 seeds weight.

The results showed that could be possible to produce the healthy production of bean, moreover, attain the optimum yield as equal as to conventional systems.

Bitter apple (Citrullus colocynthis) is one of the most important medicinal plant that grow in semi-arid and desert condition which have been used in traditional medicine. In order to evaluate the effect of drought stress and manure application rates on yield, yield components and water use efficiency of Bitter apple, a field experiment was conducted in split plot layout based on complete randomized block design with three replications in two growing seasons (2012-2014) at Sabzevar, Iran. Drought stress were three levels of evaporation from evaporation pan (50, 75 and 100 mm) which was given as main plots and four levels of cow manure (0, 20, 40 and 60 t.ha-1) which was assigned as subplots. The results showed that increasing irrigation intervals reduced the number of fruits per square meter(49%), the dry weight of the single fruit(14%) and consequently reduced yield of fruits(38%) and seeds(40%). Number of seeds per fruit and 100 seed weight was not affected by drought stress. Increased amounts of manure application caused significant increase in yield and yield components (except 100 seed weight) of Bitter apple. The lowest fruit and seed yield and yield components were observed in control treatment and the highest of them were observed as a result of application of 60 t.ha-1 cow manure. Overall, the result of this experiment showed that the highest fruit and seed yield was obtained from application of 60 t.ha-1 cow manure and irrigation after 50 mm evaporation from evaporation pan produced the highest fruit yield.

The conventional agricultural ecosystems (agroecosystems) are the complex systems which in order to produce the higher amount of food, fiber, feed and fuel have been significantly manipulated. Rapid growth of world population and demand for agricultural products resulted in higher pressure on agroecosystems. In recent decades achieving to maximum production was the main goal of conventional agriculture. In order to increase yield on production usually these agroecosystems need to external inputs such as chemical fertilizers and pesticides which have the negative effects on human health and also environment.  Sustainable and healthy agroecosystems are based on profitable farms that use fewer external inputs, integrate animal and plant production where appropriate, maintain a higher biotic diversity, emphasize eco friendly technologies that are appropriate to the scale of production, and efficiently use the renewable forms of energy. For example diversifying the farm with several crops or using appropriate rotation helps to reduce the risk of biotic and abiotic stresses. The complex nature of agroecosystem implies that any evaluation of agroecosystem health must consider the dynamics of multiple components. The current paper presents an applied method to evaluate agroecosystem health using a number of main indicators.

In order to study the agroecosystem health in four eastern provinces of Iran (i.e. Sistan and Baluchestan, South khorasan, Razavi Khorasan and North Khorasan) during 2002-2011 the current survey was conducted. The required data and information obtained from statistical database and also questionnaires. For each year the total value of agroecosystem health calculated using 29 different indexes. Different indexes calculated based on their scientific definitions. For example property distribution index calculated by dividing the total area of agricultural lands on number of farmer in each city. Because of different nature of selected indexes and also wide range of them, in order to facilitate comparison all of the calculated indexes normalized using the equation (1), in this equation Xnorm is the normalized value of each index, Xmax and Xmin are the highest and lowest value of X, respectively.Equation (1):

Based on results the highest value of structural health was calculated for Sistan and Baluchestan province and the lowest value was for Razavi KhorasanIt seems that in Sistan and Baluchestan the higher values for some of the indexes such as area under cultivation of forage and perennial crops, appropriate use of agricultural machinery and also plant diversity improved the structural health. The similar results also observed for organizational health. Lower use of pesticides and chemical fertilizers are the main reason for better conditions of organizational health in Sistan and Baluchestan province. The result for functional health was different and the best condition of functional health observed in Razavi Khorasan whereas the worst condition observed in South Khorasan. The higher value of functional health of agroecosystem in Razavi Khorasan province mainly is because of good conditions of soil structure and higher yield of different crops such as forage, vegetables, industrial crops and cereals. Considering the total agroecosystem health the highest value observed in Razavi Khorasan followed by Sistan and Baluchestan, North Khorasan and South Khorasan. Based on our classification total agroecosystem health in South Khorasan province was very poor and in other provinces was poor. The main reasons for the low value of agroecosystem health in all of the studied provinces are: soil compaction, low rainfall, using traditional methods of irrigation, insufficient cultivation of forage and perennial crops and also nitrogen fixing legumes. The fertilizer use efficiency in all of the provinces is low and these conditions could be harmful either for human and environment health.

Based on results the total agroecosystem health in South Khorasan province was very poor whereas in other three provinces total agroecosystem health was poor. The main reasons for bad condition of agroecosystem health in these provinces are: soil compaction because of unsuitable use of agricultural machinery, the low amount of precipitations, nitrogen use efficiency and area under cultivation of perennial, forage and nitrogen fixing crops. It seems that solving these problem using different methods such as increasing agrochemical use efficiency, applying good rotation and increasing water use efficiency could improve the total agroecosystem health in the eastern provinces of Iran.

The authors acknowledge the financial support of the project by Vice President for Research and Technology, Ferdowsi University of Mashhad, Iran.

Oilseed rape is the most important breeding species in Brazil, and drought stress can affect its quality and yield. Water deficit is one of the most important factors limiting the growth and production of plants, and there is currently no practical way to increase the precipitations during the dry periods. Therefore, it seems that the best way to deal with drought is to use appropriate agronomic operations and to use cultivars with more tolerance to drought. In order to evaluate the qualitative characteristics of selected varieties of rapeseed, a factorial split plot experiment was conducted in a randomized complete block design with three replications for two years (1963-1953) in Karaj. In this research, the growing season was carried out in two dates (autumn and winter) and irrigation at three levels (normal irrigation or control, irrigation from later flowering stage and irrigation from the eating stage to the next) as a factorial as main plots and spring varieties Rapeseed consisted of Jerry, Julius, Zafar, Ridge S 003, Hayola 4815 and Zabul 10 as sub plots. Statistical analysis of SAS Ver 9 was used for analysis of variance. The Duncan multi-domain test was used to compare the averages. The results showed that palmitic acid in the second year had an increase of 8% compared to the first year. Among the seedlings, the highest average seedling planting season was allocated to 18.5%. Irrigation interruptions from post-harvest phases and discontinuation of irrigation from flowering stage resulted in 12 and 25% reduction of palmitic acid respectively. The results showed that the highest content of linolenic acid in the control treatments and RGS003 cultivars, irrigation cut off stage and Julius cultivar, and discontinuation of irrigation from flowering stage to Zafar cultivar, 6 and 76.7 percent respectively. The results showed that the highest mean linoleic acid was observed in control treatments, irrigation cut off from the jollowing stage and Julius cultivar, and irrigation cut from flowering stage to Heilah cultivar 4815, respectively, with mean 21.77, 19.66 and 17.68% respectively. . The results showed that in the control and irrigation intervals, the cultivar Julius with the levels of 66.29 and 64.16 percent showed the highest amount of oleic acid in the irrigation and after irrigation period, from the flowering stage to the Hyola 4815 cultivar with an average of 26.62%, the highest average. Effect of year, planting season, irrigation, year×irrigation, year×Planting season×irrigation, planting season×irrigation, cultivar, planting season×cultivar, irrigation×cultivar and planting season×irrigation×cultivar at 1% level and season effect×season Planting was also significant at 5% level on grain yield. Effect of year, planting season, irrigation, year×irrigation, year×Planting season×irrigation, planting season×irrigation, cultivar, planting season×cultivar, irrigation×cultivar and planting season×irrigation×cultivar at 1% level and season effect×season Planting at level of 5% and year effect and irrigation at 1% level were significant on seed yield. The results of the evaluation of traits during the two years of the experiment showed that Jolvie and Hayola 4815 had the highest grain yield under irrigation conditions, and also the Hyola 4815 cultivar had a good adaptation to drought stress conditions. Therefore, the cultivars could be obtained due to grain yield and higher oil yield under both drought stress conditions and without stress; for planting in regions of the same experimental region (Karaj), the probability of occurrence of moisture stress in the late stages of growth, Recommended. Also, the planting date of autumn increased the quantitative values of rapeseed quality indices.

The most fundamental agricultural obstacle particularly in arid and semi-arid regions is water shortage. To mitigate this problem, application of some soil amendments such as water super absorbent polymers (SAP) for increasing water-holding capacity in the soil has been under attention at commercial level in recent years.
Despite numerous studies in Iran and the apparent positive and various functions have been mentioned for SAP and their advantageous in agriculture, there has not been a precise conclusion about these studies. On the other hand, variations in consumption rate, conditions and experimental treatments, makes an impossibility or hardiness to receive a conclusive result for the researchers studying one or few numbers of relevant articles.Meta-analysis is the statistical procedure for combining data from multiple studies. When the treatment effect (or effect size) is consistent from one study to the next, meta-analysis can be used to identify this common effect. When the effect varies from one study to the next, meta-analysis may be used to identify the reason for the variation. Decisions about the utility of an intervention or the validity of a hypothesis cannot be based on the results of a single study, because results typically vary from one study to the next. Rather, a mechanism is needed to synthesize data across studies (Rosenthal, 2001). Narrative reviews had been used for this purpose, but the narrative review is largely subjective (different experts can come to different conclusions) and becomes impossibly difficult when there are more than a few studies involved. Meta-analysis, by contrast, applies objective formulas (much as one would apply statistics to data within a single study), and can be used with any number of studies.
Therefore, this study was conducted with the aim of doing meta-analysis on the results of conducted researches in Iran and to answer a general question that whether the application of SAP has been successful or not, and if yes, how much of SAP is recommended. To conduct this research, articles were published during 2006-2016 with the subject of the effect of different rates of SAP on yield and yield components of crops (including cereals, legumes, medicinal and rangeland plants) were investigated. Amongst 32 articles were checked, 13 articles have enough data to conduct the meta-analysis for seed yield, dry matter yield and harvest index. The result of meta-analysis showed that the mean consumption rate of SAP for cereals, legumes, medicinal and rangeland plants were 83, 322, 1031 and 210 kg ha-1, respectively, and with this consumption rate of SAP, the mean seed yield in cereals, medicinal plants and legumes increased by 13.2, 11.2 and 27.5% (equal to 1059, 345 and 452 kg ha-1), respectively, compared with control.
Generally, the results showed that the effect of SAP on seed yield and dry matter was significant but was not significant for harvest index. The effect size of the application of different SAP rates on dry matter yield and at the whole levels was greater than its effect size on seed yield. The most effect size on seed yield was considered for the application of 100 kg ha-1 SAP and the application rates greater than 200 kg ha-1, unlike the dry matter yield, had no significant effect on seed yield. According to the results, it seems that application of 100 kg ha-1 SAP is the most appropriate rate on seed yield and dry matter increment and economical aspects. Design and implementation of the researches focused on estimation and comparison of economic benefits about water consumption as the result of SAP application can justify the relatively high cost of this ecological input and provide the necessary ground for its widespread use by farmers and producers involved in agronomy and horticultural sections.

Medicinal plants are valuable sources in Iranian natural resources whose understanding and scientific cultivation can play an important role in people’s health, job creation and preventing genetic erosion of invaluable medicinal herbs due to their improper harvest from natural habitats and non-oil exports. Indigo (Indigofera tinctoria L.) belongs to the Fabaceae family which popularly known as Neeli in Tamil and found throughout India. The roots, stems, and leaves of indigo are bitter, thermogenic, laxative, tchronic bronchitis, asthma, ulcers, skin diseases, diuretic and are useful for promoting the growth of hair. It has been reported that appropriate planting date and plant density will improve crop yield and secondary metabolite component. Yield loss due to undesirable planting date and plant density has been reported in many plants. Amin Ghafouri (2014) reported that delaying in planting date (from October to March) caused a significant reduction in plant height, canopy diameter, inflorescence number per branch, dry weight of shoots, and seed yield of Ziziphora and as density increased from 6 to 10 plants.m-2 plant height, canopy diameter, inflorescence No. per branch, dry weight of shoots, and seed yield were enhanced. In another study, was examined planting date in Achillea millefolium L. yield was reported, higher plant height, total dry matter production, Biomass yield, were observed during January planting. Ghorbani et al. (2010) evaluated the effect of planting date on yield of Cuminum cyminum reported that earlier sowing date was followed by higher seed yield. They also reported that 1000-seed weight and harvest index were not affected by planting date. Koocheki et al. (2004) showed that plant density had a significant effect on plant height and dry weight of shoots of Thymus )Zataria multiflora L.  (and Hyssop) Hyssopus officinalis L.  (Nadjafi and Rezvani Moghadam (2002) and Rahimi et al. (2009) reported the increase in P. ovata seed yield with the increase in plant density. Therefore, the objective of the present study was to determine the quantitative yield of affected by planting date and plant density. An experiment was conducted as a split-plot based on a randomized complete block design (RCBD) with three replications at the Bam, Iran, during growing seasons of 2012-2013. Four sowing dates (4 April, 19 April, 4 May, and 19 May) and four plant densities (15, 25, 35 and 45 plants.m-2) were allocated to main and subplots, respectively. Plant height, canopy diameter, number of branches, dry weight of leaf, dry weight of shoots and total dry yield of above ground matter of indigo at the first and the second cuttings were measured and calculated accordingly. For statistical analysis, analysis of variance (ANOVA) and the least significant test (LSD) at 0.05 level, were performed using SAS ver 9.1. The results showed that the simple effects of sowing date and plant density were significant (p≤0.05) on plant height, canopy diameter, number of branches, dry weight of leaf, dry weight of shoots and fresh weight of flower of indigo at the first and second cuts. The highest dry weight of leaf and dry weight of shoots was observed at the first and second cuts in the 4 April (with 464.79 g.m-2, 463.54 g.m-2, and399.75 g.m-2 and 404.04 g.m-2, respectively). However, the dry yield of above ground matter at the first and the second cuts were decreased up to 32.76 and 78.57%, respectively with the delay in sowing date from 4 April to 19 May. Generally, early sowing date because of providing a longer growing period, optimum relative humidity and also cooler weather is suitable for indigo leaf production. Based on the results of this study it can be concluded that the planting date has a meaningful effect on vegetative and reproductive characteristics of indigo. Overall, Because of the benefits of longer growing season and more soil moisture content, early planting (early spring) and highest plant density (45 plants.m-2) were the best date and density for indigo production in the climatic conditions of Bam region

  Drought stress is the main factor which limits crops production across the world. Selection of crops that are adapted to the climate of each region, the selection of suitable and resistant to environmental stresses, and the use of high-yielding farming practices play an important role in increasing the efficiency of rare source of irrigation water. Morphological and physiological recognition of drought resistance is important for the improvement of problems caused by drought conditions. In order to evaluate the yield and the yield components of selected canola varieties under different temperature and humidity regimes, a factorial split plot experiment was conducted based on randomized complete block design with three replications for two years (2015-2016) in Karaj region. The study site was a field of the Seed and Plant Improvement Institute, Karaj, Iran (35° 59′ N, 50° 75′ E, at the altitude of 1313 m). The main plot factor was included the growing season in two levels (autumn and winter). Irrigation in three levels (normal irrigation or control, Interruption of irrigation from flowering stage and Interruption of irrigation from podding stage) and spring rapeseed cultivars included Jerry, Julius, Zafar, RGS 003, Hayola 4815 and Zabul 10 were assigned to sub plots. Some traits were studied including plant height, slique number and slique length, seed yield, biological yield, 1000seed weight, harvest index. Data were analyzed using the general linear model (GLM) procedure of the statistical analysis system, SAS. When analysis of variance showed significant treatment effects, Duncan’s multiple range tests was applied to compare the means at P < 0.05. According to analysis of variances, treatments and interaction between treatments had significant effect on studied traits at 5 or 1% statistically levels. According to means comparisons, The results showed that in autumn cultivation under control irrigation, the Julius and the Zabol 10 cultivars with dry matter yield of 5592 and 5536 kg/ha, and under interruption of irrigation from flowering stage condition, Julius cultivar with yield of 2511 kg/ha, and in the case of interruption of irrigation from the podding stage, Julius and Zabul 10 cultivars with yield of 4124 and 3959 kg/ha were superior cultivars. In winter cultivation under normal irrigation conditions, the Julius and the Hyola 4815 cultivars with dry matter yield of 3551 and 3307 kg/ha, and the Hyola 4815 and the Zabol 10 cultivars in interruption of irrigation from the flowering stage with dry matter yield of 1595 and 1542 kg ha-1 and in interruption of irrigation from podding stage with 2308 and 2173 kg ha-1 had the highest dry matter yield. Generally, Application of drought stress and winter planting date led to the reduction of yield in all varieties, the results of two years experiment showed that Jolius and Hyolla 4815 cultivars had the highest grain yield under different irrigation conditions. Hyola 4815 cultivar was also suitable for drought stress (interruption of irrigation in both stages). Therefore, these cultivars can be introduced as suitable cultivars in regions may be faced with drought and non-drought stress during the growth period.

To evaluate nitrogen use efficiency in intercropping replacement ratios of maize and bean, an experiment was conducted during two successive cropping years of 2014-2015 and 2015-2016 at Agricultural Research Station, Ferdowsi University of Mashhad, Mashhad, Iran. Experimental factors were arranged as split plots in randomized complete block design with three replications. The main plots consisted of sole culture of maize and bean, row intercropping with ratios of 50%:50%, 67%:33% (2 rows of maize: 1 row of bean) and 33%: 67% (1 row of maize: 2 rows of bean). Application and no-application of nitrogen (N) fertilizer (55 kg.ha-1) were assigned to sub plots. The results showed that different ratios of maize and bean intercroppings and application of nitrogen fertilizer had significant effects on grain yield and biomass as well as nitrogen use efficiency indices (such as uptake, utilization and productivity). Maximum grain yield and biomass of bean (3462.1 and 10124.5 kg.ha-1 respectively) and maize (5974.1 and 18321 kg.ha-1, respectively) were obtained from sole cropping of bean and maize. In both crops, N utilization efficiency was higher in all treatments when nitrogen productivity was calculated using grain yield. In nitrogen application treatment, the row intercropping ratio of 50:50 of bean and maize had higher nitrogen uptake efficiency for both crops. Also, the ratio of planting 1 maize: 1 bean (50% maize: 50% bean) had the highest total land equivalent ratio (1.10) using grain yield, nitrogen uptake efficiency (2.30) and nitrogen productivity efficiency (using grain yield (1.98) and biological yield (2.02)). Therefore, it can be concluded that the use of maize and bean row intercropping is an environmental friendly cfrop management pratctice to reduce nitrogen losses and improve its uptake efficiency, and to prevent the excessive use of chemical fertilizers and improve the productivity of these inputs in agroecosystems.

The role of leaf area index (LAI) in terrestrial ecosystems is undeniable. LAI affects the amount of carbon, water and energy metabolism. Also, many agronomic, environmental and meteorological applications require information on the status of LAI. The time series of the spectral indices obtained from the remote sensing indicates its usefulness in detecting regional-scale LAI changes. So, the desire for the development of models for estimating LAI was increased with using satellite images. Vegetation Indices (VIs), especially the Normalized Difference Vegetation Index (NDVI) and Ratio Vegetation Index (RVI), are most widely used. According to the different sensitivity of VIs to the value of LAI and vegetation characteristics, in this study, we tried to determine an algorithm with a higher accuracy to estimate the LAI of wheat using more variables (VIs). In this study, regarding the wheat growth period in Astan Quds Razavi (AQR) farms, the Landsat 8 satellite images were used from November 22, 2014 to June 20, 2015. LAI was measured simultaneously with passing of Landsat 8 (16-day intervals) from AQR Fields of Mashhad (in five dates from 17 farms) during wheat growing season in 2014-2015.
After pre-processing of satellite images, VIs including the Difference Vegetation Index (DVI), NDVI, RVI, Transformed Difference Vegetation Index (TDVI), Soil Adjusted Vegetation Index (SAVI), Infrared Percentage Vegetation Index (IPVI), Greenness Index (G1 and G2) and Enhanced Vegetation Index (EVI1 and EVI2) were calculated. To select the best variables and the equation for estimating LAI, simple regression (linear, quadratic and exponential) and multiple linear regression (Backward and Forward) methods were used. Finally, to validate and assess the accuracy of the presented models, the mean square error (RMSE), Mean Absolute Error (MAE), Point accuracy based on a percentage of actual value (E%) and correlation coefficient (r) was used. The results of this study showed that simulation of LAI based on the existing equations in the references using the NDVI, EVI1 and EVI2 indices extracted from Landsat 8 satellite images has low accuracy (RMSE:2.71, 3.65 and 3.65). This confirms the necessity of examining and calibrating equations. The results indicate that the accuracy of the wheat LAI estimation by using the NDVI and SAVI index was increased by exponential functions (RMSE:1.18 and 1, respectively) compared to the linear model (RMSE:1.46 and 1.26, respectively). This increase was due to a more accurate estimation LAI lower than 4 and the fixed value of LAI simulated in a range of actual LAI higher than 6. The accuracy of LAI estimation was increased with combination of two VIs (NDVI and SAVI) compared to the linear model of each index separately. Also, the highest accuracy of LAI estimation from the combination of G2 with SAVI and EVI1 (RMSE: 1.03, 1.03, respectively) was observed due to the higher sensitivity of G2 to medium and high LAI compared to NDVI. In addition, the backward and forward regression model was improved the accuracy of wheat LAI estimation compared to other models, due to the greater sensitivity of this model to LAI higher than 6 (RMSE: 0.87 and 0.95, respectively). Although the accuracy of wheat LAI estimation by the forward regression model was higher than all models, but its calculation requires the use of many parameters. Since LAI is an important biophysical parameter in ecological modeling. Accurate and fast estimation of this parameter in large scale for ecological models such as yield and evapotranspiration, and carbon exchange is very important. Considering the results of this research and the opinions of other researchers, it can be stated that the accuracy of the exponential functions and multiple linear regression (Forward regression model) for estimating LAI was higher than simple linear regression.

In recent years, the effect of ecological inputs on soil properties and plant growth characteristics has received renewed attention. Although the utilization of mineral fertilizers could be viewed as the best solution in terms of plant productivity, this approach is often inefficient in the long-term in tropical ecosystems due to the limited ability of low-activity clay soils to retain nutrients. Biofertilizer is a substance which contains living microorganisms which, as applied to seed, plant surfaces, or soil, colonizes the rhizosphere or the interior of the plant and promotes growth by increasing the supply or availability of primary nutrients to the host plant. Biofertilizers add nutrients through the natural processes of nitrogen fixation, solubilizing phosphorous and stimulating plant growth through the synthesis of growth-promoting substances. Biofertilizers can be expected to reduce the use of chemical fertilizers and pesticides. Humic substances are a group of heterogeneous molecules that are bonded together by weak forces; therefore, they have a high chemical stability. This material included of 65 to 80 percent of total soil organic matter. Humic acid influences soil fertility through its effect on the water-holding capacity of the soil. Humic acids make important contributions to soil stability and soil fertility leading to exceptional plant growth and micronutrient uptake. Mycorrhiza arbuscular fungi are other coexist microorganisms that improves soil fertility, nutrients cycling and agroecosystem health. Mycorrhizal fungi are the most abundant organisms in agricultural soils. Many researchers have pointed to the positive roles of mycorrhizal fungi on plants growth characteristics. Echium amoenum is a wild perennial herb and known in Iran as Ox-Tongue. It is one of the important medicinal plants in Iranian traditional medicine. Petals of Iranian Ox-Tongue have been advocated for a variety of effects such as demulcent, anti-inflammatory and analgesic, especially for common cold, anxiolytic, sedative and other psychiatric symptoms including obsession in folk medicine of Iran. Despite of many researches on the effect of organic acids and biofertilizers on different crops, information on the effects of these factors for many medicinal plants is scarce, therefore, in this study effect of eco-friendly inputs in cultivation of Echium amoenum in conditions of Mashhad was studied. In order to evaluate organic acids, plant growth rhizobacteria and different species of mycorrhiza on yield and yield components of Iranian Ox-Tongue (Echium amoenum), a split plots experiment in time based on RCBD design with three replications was conducted in 2011-2014 growing seasons, in Ferdowsi University of Mashhad, Iran. Seven different types of soil amendments and biofertilizers concluded humic acid, fulvic acid, Nitroxin® (containing Azotobacter spp. And Azospirillum spp.), Biophosphorous® (containing Bacillus sp. and Pseudomonas sp.), Biosulfur® (containing Thiobacillus spp.), Mycorrhiza (Glomus mosseae), Mycorrhiza (Glomus intraradices), and no fertilizer as control and agronomic years (2 and 3 agronomic years) assigned to main and sub plots, respectively. The results showed that the highest dry flower yield obtained in humic acid treatment. Humic acid and fulvic acid increased seed weight per plant 38 and 25% and seed number per plant 19 and 17% compared to control, respectively. Fulvic acid, nitroxin, biophosphorous, biosulfur, mycorrhiza (Glomus mosseae) and mycorrhiza (Glomus intraradices) increased dry flower yield 27, 20, 4, 26, 30 and 28% compared to control, respectively. The highest flower and seed harvest index obtained in mycorrhiza (Glomus intraradices) and humic acid treatments, respectively. It seems that different species of mycorrhiza improved morphological characteristics and yield of Echium amoenum due to provide better conditions to absorption and transportation of nutrient to the plant. It has been reported that organic acids provided favorable conditions for plant growth and development through improvement of physical, chemical and biological properties of the soil, therefore, it can be concluded that improvement of most of studied traits in the present study were due to use of organic acids. In general, the findings of this research showed that application of ecological inputs, while increasing yield and yield components of Iranian Ox-Tongue, can reduce dependence on chemical inputs and their environmental risks and can be used to develop sustainable agriculture and protect the health of the environment.