حمیدرضا اصغری

In this study, to investigate the phytochemical changes of essential oil and growth performance of Thymus daenensis Celak. affected by light and salicylic acid, an experiment was conducted as a split plot in a completely randomized block design with three replications. The tested factors included salicylic acid foliar spraying at three levels (0-0.2 M) and two light levels (50-100%). Special nets were used to create 50% shading. The amount of light reduction compared to the control treatment was measured by a lux meter. Foliar spraying was done before flowering. Plant essential oil was obtained from flowering aerial branches by Clevenger apparatus and analyzed by GC-MS. The highest yield of flowering branches and height were from 0.1 M salicylic acid (33.35 kg/ha and 24.33 cm, respectively) and full light treatments (32.50 kg/ha and 22.47cm respectively). The highest amount of chlorophyll a (5.2 mg/g), chlorophyll b (1.98 mg/g) and the number of lateral branches (180/35) due to the application of 0.1 M salicylic acid × 50% light treatment significantly increased compared to the control treatment. The amount of essential oil decreased with increasing light intensity and the use of salicylic acid improved this attribute. So that with full light intensity it reached the lowest level of 1.95% and the application of 0.1 M salicylic acid increased the percentage of essential oil (3.1) compared to the control treatment. The most components of thyme essential oil with the use of 0.1 M salicylic acid× 50% light treatment include carvacrol (4.4%), paracetamol (14.6%), beta-caryophylline (5.95%). Also, the highest amount of thymol was related to 0.1 M salicylic acid treatment (59.66%) and full light (57.8%). In general, the results showed that the use of salicylic acid has a positive effect on improving the qualitative and quantitative characteristics of the essential oil components of thyme. (5.95%). Also, the highest amount of thymol was related to 0.1 M salicylic acid (59.66%) and full light (57.8%). In general, the results showed that the application of salicylic acid had a positive effect on improving the qualitative and quantitative characteristics of the essential oil components of thyme.

The use of biological fertilizers can be effective and beneficial in abiotic environmental stresses specially in drought stress, arid and semi-arid regions of the world.

An experiment was conducted to investigate the effect of deficit irrigation stress and Pseudomonas bacteria on some morpho-physiological traits of two potato cultivars at the research farm of Shahroud University of Technology located in Bastam region in 2010. Treatments included irrigation cycles as the main factor at three levels (7, 10, and 14-days), Pseudomonas bacteria (inoculation and non-inoculation) and cultivar at two levels (Savalan and Agria) as the sub-factor with three replications.

The results showed that the highest dry matter accumulation in the aerial part was observed in the 7-day irrigation cycle and inoculation with Pseudomonas bacteria. The number of tubers was increased about 12.66% because of inoculation with Pseudomonas fluorescens per square meter. Savalan cultivar interaction and 7-day irrigation cycle also obtained the highest number of tubers with an average of 166.39 per square meter. The application of inoculation with Pseudomonas fluorescens increased chlorophyll A by 9.3%. It compared with non-bacterial inoculation. Chlorophyll B had the highest chlorophyll content in the main treatments of the 7-day irrigation cycle and Agria cultivar. The highest amount of potassium content was obtained at the rate of 2.06% at the highest irrigation cycle (14-day). The application of inoculation and non-inoculation with Pseudomonas caused the highest amount of proline at 14-day irrigation cycle. Inoculation with Pseudomonas bacteria increased the final tuber yield about 22.85%. Furthermore, Savalan cultivar increased the final tuber yield about 110.09% in the 7-day irrigation cycle compared to the 14-day. Finally, the 7-day irrigation cycle was the best irrigation cycle to increase the morpho-physiological traits, chlorophyll, number of tubers, and the final tuber yield. Inoculation with Pseudomonas bacteria increased the effectiveness of these traits. Also, the production of compatible osmolytes (proline and potassium) improved drought stress tolerance in 14-day irrigation cycle. Growth-promoting bacteria improves seed germination, root propagation, shoot and root weight, leaf area, chlorophyll content, hydraulic conductivity, protein, nutrient absorption and plant yield (Batool et al., 2020). Growth-promoting bacteria of polysaccharides increases biomass production under drought stress conditions (Daffonchio et al., 2015). Potassium is one of the most important osmolytes under drought stress conditions and adverse conditions (Anschütz et al. 2014). Cellular and physiological responses are carried out through organic salts as proline to reduce cellular damage during drought stress. It is an osmotic regulator (Merwad et al., 2018)

The 7-day irrigation cycle was the best irrigation cycle to increase the morpho-physiological traits, chlorophyll, number of tubers, and the final tuber yield. Inoculation with Pseudomonas bacteria increased the effectiveness of these traits. Also, the production of compatible osmolytes (proline and potassium) improved drought stress tolerance in 14-day irrigation cycle.

This research was carried out in a factorial split plot experiment based on a randomized complete block design with four replications in Semnan Agriculture Research Center, Bastam, central Iran, in 2019. Experimental treatments included irrigation as the main factor at three levels of 100, 75 and 50% of water requirement and sub-factors including cultivar at three levels (Titicaca, Q26 and Q29) and priming at two levels (no priming and hydropriming) as sub-factors. The percentage of water requirement of the plant was calculated using the CROPWAT program and applied from the 6-leaf stage of the plant. The results showed that drought stress reduced leaf area index, 1000-seed weight and grain yield in all three cultivars. Percentage of protein, malondialdehyde, proline, activity of antioxidant enzymes including catalase and ascorbate peroxidase increased in plants under drought stress. Hydropriming increased leaf area index and grain yield. Among the three cultivars tested, hydroprimed plants of Q26 genotype had the highest leaf area index, 1000-seed weight and grain yield compared to the other cultivars. Cultivar Q26 had the highest grain yield when supplied with 75 and 100% of water requirement and Titicaca cultivar had the highest grain yield (1067 kg/ha) in the presence of severe drought stress (i.e. 50% water requirement). In conclusion, Titicaca cultivar was more resistant to drought than other cultivars and cultivation of this cultivar is recommended in Bastam region. In the scope of the research, the application of hydropriming can be suggested to improve the physiological traits of quinoa under drought stress.

The cultivation of quinoa (Chenopodium quinoa Willd), an annual plant with high nutritional and economic significance, is expanding throughout the world. Quinoa is a traditional Andean seed crop highly tolerant to abiotic stresses. Since most seed crop cultivars are sensitive to drought stress, quinoa is regarded as a valuable candidate for the plant's exposure to harsh environmental conditions. Due to the importance of quinoa in arid regions, the effects of seed priming on yield and certain morphological and physiological traits were investigated in this study.

A factorial split-plot experiment based on a randomized complete block was designed with four replications was conducted in 2019 at Damghan Research Farm Station. The experimental treatments included drought stress based on the plant's water requirement at three levels (100% (control), 75%, and 50%) as the main factor, and sub-factors included three cultivars (Titicaca, Q26, and Q29) as well as priming at two levels (no priming and hydropriming) as a factorial experiment into sub-levels. To perform water requirement (WR) treatment, WR were calculated using the CROPWAT program and then applied to the 6-leaf stage plants.

The results demonstrated that drought stress (50% WR) reduced  relative leaf water content (13.1%), leaf membrane stability index (21.2%), chlorophyll content (38.7%), 1000-seed weight (18.2%), number of panicles per plant (27.5%), number of seeds per panicle (7.71%), and seed yield (40.4%). The use of hydropriming increased the membrane stability index, leaf chlorophyll content, 1000-seed weight, and the number of panicles per plant. Under 50% WR, the activity of antioxidant enzymes such as catalase and leaf ascorbate peroxidase increased by 139.58 and 42.55 percent, respectively, compared to the control. Additionally, drought stress increased quinoa seed protein content and decreased seed yield.. The percentage of seed yield reduction in drought stress was 50% and 75% of WR and was lower in Titicaca than the other two cultivars.  The comparison of the mean of irrigation interactions in the cultivars revealed that 100% WR produced the maximum quantities of Chl a, Chl b, and carotenoids in all three cultivars. Additionally, seed priming boosted the Chl a, and Chl b concentrations in Titicaca and Q26. Furthermore, the highest biological yield in the Damghan region was achieved in Q26 with 100% WR. Under normal irrigation conditions, Q26 cultivar had the highest seed yield, whereas under drought stress conditions, the seed yield of all cultivars decreased significantly. Nevertheless, this decline in the Titicaca cultivar was 12% less than in Q26 and Q29. The findings of the mean comparison revealed that priming improved seed yield in all three cultivars, with the Q29 cultivar producing the maximum seed yield at 1,452.03 kg/ha.

In general, Titicaca cultivar was more resistant to drought stress than other cultivars, hence its cultivation is encouraged in the Damghan region. Within the scope of this study, the use of hydropriming to improve quinoa's physiological features in conditions of drought stress is suggested. In conclusion, the results demonstrated that seed priming significantly increased seed yield, biological yield, leaf area index, and chlorophyll content in drought-stressed quinoa cultivars. These results indicated that seed priming can play a significant role in enhancing quinoa's drought resistance under low irrigation conditions. This study could contribute to the understanding of seed priming effects, which could be applied as an effective strategy to mitigate the negative effects of drought stress on quinoa cultivars.

Drought as the most important problem of agricultural development in Iran is one of the main obstacles in the production of agricultural products. Because the global approach to the production of medicinal plants is effective in improving the quantity and quality of the substance, today the use of salicylic acid as one of the plant hormones in increasing plant resistance to stresses such as drought has increased. In this study, the effect of foliar application of salicylic acid on the growth and phytochemical characteristics of Thymus daenensis Celak in low irrigation conditions was studied. The experiments were performed as a split plot in the form of a randomized complete block design with 3 replications in research field of Jihad University Medicinal Plants Research Institute located in Heljard, Karaj in 2017. The results showed that low irrigation stress significantly reduced plant height, number of lateral branches, yield of flowering branches, chlorophyll a and chlorophyll b, percentage of essential oil and essential oil constituents including thymol, carvacrol, paracetamol and beta-caryophylline. On the other hand, the use of salicylic acid reduced the negative effects of poor irrigation conditions. Also, the highest growth and phytochemical indices were observed in plants treated with salicylic acid, which indicates the role of elastores in stress relief. The results showed that salicylic acid by inducing stress tolerance moderated the damage caused by under irrigation stress in thyme and increased the growth rate of stressed plants. The findings of this study can be used to reduce plant damage in low water areas.

In order to investigate the effect of biological fertilizers and application of metribuzin herbicide on growth and yield of tomato (Lycopersicon esculentum Mill.) and weed population, a field experiment was conducted as randomized complete block design with three replications at the research field of Shahrood University of Technology. The experimental treatments included; weed free and weed infest all season, inoculation of root of tomato transplant with Pseudomonas fluorescens and Azotobacter crococum separately, soil application of metribuzin herbicide 500, 1000 and 1500 g.ha-1 and the mentioned dosage of herbicide (500, 1000 and 1500 g.ha-1) along with inoculation of P. fluorescens and A. crococum. Results showed that A. crococum and P. fluorescens in combination with low doses of herbicide (500 g.ha-1) increased bacterial colonization by 57.89 and 52.63 percent compared to the control (weedy) treatment respectively. High doses of herbicide (1500 g.ha-1) alone or in combination with bio-fertilizers decreased bacterial colonization in soil and growth and yield of tomato. Also, A. crococum and P. fluorescens in combination with low doses of herbicide increased the number of ripe fruit of tomato by 26.4 and 24.8 percent in comparison to weed free treatment respectively. Based on the results of this experiment, application of bio-fertilizers (A. crococum and P. fluorescens) together with 500 g.ha-1 metribuzin herbicide while improving the growth and yield of tomato and optimal weed control can be an important step towards achieving sustainable agricultural

Biostimulants originate from natural and biological sources and in addition to improving plant growth and soil yield, they can protect plants from environmental stresses and stimulate the synthesis of secondary metabolites involved in plant defense mechanism. In this study, to study the effect of foliar application of various amino acids on the biochemical responses of Physalis alkekengi L. an experiment in the form of randomized complete block design with 3 replications in the farm of research Institute of Medicinal Plants of jahad University in Karaj was conducted in the cropping year of 2018-19.Treatments at five levels of amino acid foliar application including {control (A0), tryptophan (1 mg/L) (A1), glycine (1 mg/L) (A2), tyrosine (1 mg/L) (A3) and arginine (1 mg/L) (A4) were administered. Measured variables included: carotenoids, anthocyanins, proline, phenol, beta-carotene, lycopene, ascorbic acid, and alkaloids. The dimensions of the plots were 3×3 m, the distance between each plot was considered to be one meter. Planting operations were done manually in May 2017. The distance between the plants on the culture lines was 25 cm and the distance between the culture lines was 60 cm. Foliar spraying on plants began before flowering. At the time of sampling, three replicates were taken from each treatment and three samples were taken from each replication. Chlorophyll and carotenoids by Lichtenthaler method, anthocyanin by Mita method, proline by Bates method, phenol by Meda method, beta-carotene by Amarowicz method, lycopene by Montesano method, ascorbic acid by titration method, and alkaloid by Iranian Herbal Pharmacopeia method, were measured. The results showed that foliar application of amino acids had a significant effect (p ≤ 0.01) on all evaluated traits and the highest amounts of carotenoids (12.83 mg/gfw), beta-carotene (0.035 mg/gfw), and lycopene (0.017 mg/gfw) from arginine foliar application, highest ascorbic acid (24.2 mg/gfw) and alkaloids (42.25%) from tryptophan foliar application, highest proline (1.4 mg/gfw) Glycine and the highest levels of anthocyanin (12.25 mg/gdw) and phenol (32.44 mg/gfw) were obtained from the control treatment (no foliar application). In general, the results showed that foliar application of amino acids as a biological stimulant had a positive effect on improving the quality characteristics of the Physalis alkekengi L and increased the production of biochemical compounds of the plant.

Borage officinalis L. is an annual herbaceous plant that is distributed in temperate and subtropical regions, especially in the Mediterranean. Nowadays, foliar application of salicylic acid (SA) as one of the growth regulator for improving plant stresses tolerance such as drought stresses. Biochar is a carbon-rich product in the stable form that benefits from organic fertilizers and is used soil fertility. Considering the importance of medical plant cultivation especially in the drought region, investigation the effects of water deficit on Borage officinalis L has particular importance and according to previous studies on the positive effect of salicylic acid and biochar on mitigation of adverse effects of drought as well as improving water relations in soil, therefore this study aimed to investigate the effects of biochar and salicylic acid (SA) on some characteristics of Borage officinalis L under different irrigation intervals

These experiments were performed in a four replicated-split plot factorial arranged in CRBD with three factors irrigation intervals (5, 10, and 15 day) in the main plots and biochar application (0, 5 and 10 tons per hector) and foliar application of salicylic acid (0,0.5Mm) in sub plots. This study was carried out in research field of Shahrood university of technology, Shahrood, Iran during 2017-2018.

the results indicate that with increasing irrigation intervals in all biochar levels, leaf relative water content (RWC) significantly decreased and biochar application had no significant effect on drought stress. Salicylic acid increased leaf relative water content (RWC) in both irrigation intervals of 10 and 15 days compared to non-treated treatments but it had no positive effect on stress reduction due to increases irrigation intervals. As the irrigation intervals increased, flavonoid levels also declined significantly, salicylic acid partially moderating its use, but biochar application had different effects on flavonoid depending on irrigation intervals. Increasing irrigation intervals up to 10 days increased the level of anthocyanin, but with increasing irrigation intervals to 15 days, it decreased significantly. Biochare application had no significant effect on anthocyanin content (both under and without salicylic acid application) but with increasing irrigation intervals to 10 days, biochar application alone without salicylic acid caused anthocyanin content increased. Nitrogen percentage of borago officinalis.L leaf increased significantly with 5 tons/ha biochar for 5 days irrigation intervals and 10 tons/ha biochar for 15 days irrigation intervals, compared to control (non-biochar). The results also show that the application of biochar 10 tons/ha at 10 and 15 days' irrigation interval moderated the stress caused by increased irrigation interval for leaf nitrogen. Increasing irrigation intervals also reduced the number of flowering shoots, which improved by biochar and salicylic acid application.

biochar had a positive effect on the improvement of some physiological and qualitative indices of borago officinalis. L under drought stress condition, but there were no significant differences between different levels of biochar in terms of positive effects in reducing the effects of irrigation intervals on some traits, Besides, the simultaneous application of biochar and salicylic acid in most traits increased their efficiency in reducing drought stress effects.

Salinity is one of the environmental abiotic stresses and most important factors limiting the growth and production of plants around the world, which dramatically affect various aspects of plant growth and development through anatomical, morphological and physiological changes (Siringam et al., 2011). Saline environments decrease the growth and yield characteristics of plants and increase some physiological properties such as proline content and electrolyte leakage (Noreen et al, 2010). On the other hand, in the recent years, the role of symbiotic fungi and polyamines in plants tolerance to environmental stress such as saline conditions are pronounced. Morever, due to the importance of medicinal plants, many researches of plant sciences have focused on the various aspects of the application of these plants (Vafadar et al., 2018). Therefore, the present study was conducted to investigate the growth and physiological response of stevia (Stevia rebaudiana Bertoni) medicinal plant to inoculation with endophytic fungi and foliar application of spermidine polyamine under salt stress conditions.

This experiment was conducted at research greenhouse of Genetics and Agricultural Biotechnology Institute of Tabarestan (GABIT) at Sari Agricultural Sciences and Natural Resources University using factorial arrangement based completely randomized design with three replicates in spring and summer of 2016. The treatment consisted of salinity in three levels (0, 6 and 12 dS/m), fungal symbiosis treatments including four levels [non-inoculated (control), inoculation with Piriformospora indica (Pi), inoculated with Trichoderma virens (Trich) and co-inoculation of two fungi (Pi+Trich)] and foliar application of spermidine in three levels (0, 0.75 and 1.5 mM). Seedlings of stevia after inoculation with fungi transfered to adaptation chamber for 40 days and then moved to the greenhouse. Plants were irrigated with tap water until the end of vegetative stage and then irrigated with saline water treatments containing mixture of distilled and Caspian sea water. The Spermidine was foliar applied one week before salinity stress. Two weeks after salinity stress, leaf samples were prepared to measure leaf relative water content (RWC), electrolyte leakage (EL), proline content and soluble sugars. Finally, the plants were removed from the pots and the growth and yield traits were measured.

The result showed that in saline conditions, endophytic symbiosis, especially Pi+Trich, increased the stem dry weight (40-64%) and leaf dry weight (44-50%), relative water content (5-30%) and proline content (40-64%), and reduced EL (11-20%). Also spraying 0.75 mM spermidine signiticantly increased both leaf dry weight and plant height. Fungal symbiosis, especially Pi+Trich, and spermidine 0.75 mM resulted in an increase in the RWC. Also, spraying with polyamine spermidine at both concentrations of 0.75 and 1.5 mM increased soluble sugars and inoculated with endophytic fungi, particularly co-inoculation of two fungi, led to a reduction in the content of sugar (17%) in the stevia leaf. At the most levels of salinity and fungal treatments, spermidine, especially at the rate of 0.75 mM, led to increase in stem diameter (10-35%) and leaf area (35-46%).

In general, the results of the present study indicated a negative effect of salinity on the growth and physiological characteristics of the stevia plants. However, inoculation of endophytic fungi, particularly co-inoculation of Pi and Trich, improved the growth and physiological parameters and ameliorated adverse effects of salinity in stevia plants. Morever, the spermidine (especially 0.75 mM) induced salt stress tolerance in stevia plants and showed a synergetic effects with endophytic fungi in terms of the mentioned parameters.

Seed pre-treatment with ultrasound wave is a bio-physical method of seed priming, seed imbibition with water is also a way to improve germination, so in order to investigate the effect of ultrasound pretreatment and 4 imbibition hours' time (0, 3, 6 and 9 hour) on germination and biochemical feature of Echinacea purpureaL., A completely randomized design experiment with 8 treatment and 3 replications was conducted. Treatments including 4 imbibition time (I) and ultra-sonic wave (W) with this arrangement (I0W0, IW, I3W0, I3W, I6W0, I6W, I9W0 and I9W). The results of analyses of variance showed that the effect of imbibition times and ultrasonic wave on total characteristics was significant. Ultra-sonic wave and imbibition times in most treatment increased germination percentage then to control. The highest and lowest amount of germination percentage respectively in I6W and control (I0W0) with means of 97.3 and 84% observed. The highest amount of solution protein in treatments I6W and I9W with average of 43.2 mgg-1 FW and the lowest amount of it in control with average of 27 mgg-1 FW was observed. Ultra-sonic wave and imbibition times in total treatment could show higher amount of total sugar then to control. The highest amount of starch in control and I0W treatment with average of 5.8 mgg-1 FW and the lowest amount of it in treatment IW6 with average of 3.02 mgg-1 FW observed, and the end imbibition with ultra-sonic wave could improve germination percent and germination rate in Echinacea purpurea seeds.

Application of organic fertilizers such as biochar is one of the most effective techniques to avoid immobilization of P chemical fertilizers in soils. In order to evaluate the effect of rice bran biochar (produced at 550º C) alone, biochar mixed with P, and that enriched with P on some chemical properties of soil and yield of corn plant, a field experiment was conducted based on a completely randomized design with 7 treatments and 3 replications. The treatments included a control, triple superphosphate (350 kg ha-1 TSP), biochar at 2 levels (2 and 4 t.ha-1), biochar enriched with TSP (2 and 4 t.ha-1 biochar enriched with, respectively, 350 and 700 kg TSP), and 2 ton ha-1 biochar mixed with 350 kg TSP. To determine the chemical properties of soil and yield of corn, soil sampling was done three times during the growing season while plants were sampled 120 days after sowing. The results revealed that pH value decrease and soluble and available phosphorus increased in almost all treatments including biochar. The biochar with TSP was the best treatment (soluble and available P increased by 190% and 105%, respectively, compared to the control).  Grain yield was the lowest in the control (9.1 t.ha-1) and the highest in 4 t.ha-1 biochar enriched with TSP (15.9 t.ha-1). The treatment including 4 t.ha-1 biochar showed the highest P concentration in corn root (0.47%) and grain (0.79%). It is concluded that although TSP alone was able to increase available P in the soil, but its effects will decrease in longer times. Application of biochar mixed with TSP had the best effect on the P availability and its uptake by the plant. In general, for soils with low content of  P and organic matter, treatment of 4 t.ha-1 biochar enriched with 700 kg TSP is recommended to obtain the highest grain yield. However, environmental issues caused by the overuse of phosphorus fertilizers and the costs imposed on farmers must be considered.

These experiments were performed in a three replicated-split plot factorial arranged in CRBD with three drought stress levels ((I0) (no-stress) I1 (moderate stress) I2 (severe stress)) in the main plots and foliar application of different amino acids (Tyrosin, Argenin, Tryptophan, Glycine and without foliar application as control treatments) in subplots. This study was carried out in the research field of the Iranian institute of medical plant, Karaj, Iran during 2017-2018. This study stimulated plant height, number of fruit, total dry matter, SPAD, chlorophyll a(CHLa), chlorophyll b (CHLb), total chlorophyll (CHLt), and caretonied. The results indicated that drought stress had significantly affect (p ≤ 0.01) on all traits except SPAP, and also foliar application of amino acids was significant in all traits. Interaction effects CHLb, CHLt, and caretonied was significant. The highest amount of plant height, number of fruits, fruit dry weight, total dry matter, and SPAD obtained from control (no drought stress) and the highest amount of CHLa, CHLb, and CHLt, shown in moderate stress and finally, Severe drought had the Lowest amount of all treatments. Besides, the most number of fruit, fruit dry matter, and CHLA, CHLB, CHLT was in the foliar application of Arginine and plant height and carotenoids and total dry matter and SPAD were in glycerin and Tyrosin respectively. Fruit dry matter is the main index of assessment and increased by argenin application by 39.8 percent than control. Furthermore, nonfoliar application(control) had the lowest amount in all traits. in general, Biostimulants application improved the vegetative and morphophysiological characteristics and caused a reduction in chemical fertilizer consumption and sustainable agriculture progress.

Understanding the spatial relationship of weed populations and crop growth and yield within fields is increasingly important as methods are being developed for the site-specific management of weeds. Knowledge of spatial variability helps to improve weeds and crop management efficiency. It is well known that weed populations have a patchy distribution and a weed patch is considered stable if is consistent with density and location over time. Most of the spatial variability studies about weed populations have provided very precise information for site-specific recommendations and they are referred to as density data. The knowledge of spatial patterns within a field is critical not only to farmers for potential variable rate applications, but also to select homogenous zones within the field to run crop models with site-specific input to better understand and predict the impact of weeds, soil and landscape characteristics on spatial and temporal patterns of crop yields to enhance resource use efficiency at field level. Remote sensing and geostatistic methods have been widely explored as a tool for detection and mapping of weeds distribution in agricultural crops. Remote sensing is the science and art of obtaining information about an object, area, or phenomenon through the analysis of data acquired by a device that is not in contact with the object, area, or phenomenon under investigation. Thus, on the basis of different types of platforms carrying specific sensors, agricultural remote sensing could generally be categorized into satellite, aerial, and handheld or tractor mounted remote sensing. The cross-semivariogram analysis is one of geostatistical methods to describe the joint spatial dependence, or continuity between two variables such as crop yield and density of weeds and other pairs of variables that are influenced by the same local conditions or spatial processes. The objective of this study was to describe the spatial relationship between winter wheat and weeds using geostatistic and remote sensing.

Geostatistic and remote sensing techniques were used to describe spatial relationship between weeds distribution and wheat biological and grain yield on a winter wheat fields located in Faculty of Agriculture, Shahrood University of Technology in growing season 2017-2018. Wheat traits such as biological and grain yield, weed density, and biomass were measured at 110 points of field based on an 8×8 m grid. Also, in order to investigation of biological and grain yield of wheat using remote sensing, an aerial image was taken by a quadcopter from the height of 120 m and then numerical values of aerial image pixels extracted and analyzed using geostatistics methods. Before subjecting data to spatial statistical analysis, they were log-transformed and detrended by a median polishing procedure as described previously. To describe the co-continuity of two variables (wheat yield and weeds populations) cross-semivariance was used. Semivariograms and cross-semivariograms were calculated both using GS+ and Variowin (Software for spatial data analysis in 2D, Spring Verlag, New York, USA) softwares, respectively.

Semivariogram analysis showed that total weed density and biomass had patchy patterns on the field. Cross-semivariograms showed weed density and biomass had negative spatial correlation of 75.89 to 62.50% with wheat biological yield and negative spatial correlation of 91.9 and 56.25 with grain yield of wheat, respectively. Remote sensing data showed a strong correlation of 88.23 and 78.12% with biological and grain yield of wheat, respectively. High spatial dependence was observed between the maps of biological and grain yield of wheat. Also, weed density and biomass patterns on the maps of weeds were similar to patterns of wheat biological and grain yield on the maps. Competition for resources among plants has long been considered to generate stress for plants and to be important for determining the distribution of species, as well as their evolution. Weeds reduce crop yields primarily by competing with the crop for limited resources (light, water, nutrients, etc.). Knowledge of the distribution of weeds across the field creates an opportunity for site-specific weed management. One potential way to utilize this information is through variable-rate herbicide application (VRA). While mapping weeds via field scouting or remote sensing for precisely varying application can be expensive, photographs taken from an airplane at times when weed-crop discrimination is good may be a more affordable method of roughly mapping weed patches to allow for some reduction in herbicide use.

Base on this experiment results, weed density and biomass had a patchy distribution and so they can, depending on their impact degree, affect the growth and yield patterns of wheat in a non-uniform manner. Also geostatistical and remote sensing data has great potential for study of plant distribution and their relationships on the fields.

Canola oil seed species currently hold the third position among oil seed crops and has lowest saturated fatty acids content (Ashraf and Mcneilly 2014). When commercial production was first considered in Iran, site location and planting date were thought to be the two most important cultural decisions. A long term drought stress effects on plant metabolic reactions associates with, plant growth stage, water storage capacity of the soil and physiological aspects of plant. Generally, the number of seed per plant, number of seeds per pod and also seeds weight are considered the yield components of canola (Angadi et al., 2003). A study by Kajdi and Pocsai (1993) on the effects of irrigation on 21 rapeseed cultivars showed that, as irrigation frequency increased, the seed yield increased as well. Indeed, they noticed the high seed yield only in the cultivars with high levels of erucic acid and glucosinolate. Moreover, it has been reported that drought or heat stress during flowering and seed filling stages could stop the flowering and caused decrease of seed formation, oil percentage and the seed yield to decrease (Johnston et al., 2002). If cultivars could be selected in a way that produce an acceptable economic yield in less watering condition and are more stress tolerant under the stress intensity conditions, they would be practically very useful for developing rapeseed cultivation in such regions.

In order to study the effect of delayed planting and drought stress on grain yield grain component, saturated and unsaturated fatty acids, oil content and glucosinolate of seeds and proline content of rapeseed, a field experiment was conducted as split-plot arrenged in a Randomized Complete Block Design (CRBD) with three replication in Seed and Plant Improvement Research Institute of karaj in 2014-2016. Experimental treatments were included sowing dates in two levels included: 20th of October (normal cultivation) and 5th of November (delayed cultivation), Irrigation in 2 levels includes: normal Irrigation (control) and drought stress (irrigation withholding in pod formation) as well as hybrids and hybrids Rapeseed autumn included: Neptune, Elvise, Okapi, Tassilo, GKH0224, GKH2624 and GKH3705.

The results of the experiment showed that planting date, irrigation and cultivar were significant on all traits Except for eicosenoic acid, Results showed that delaying the planting date decreased pod number per plant, 1000-grain weight yield, oil content, eicosenoic acid proline, whereas behenic acid and seed glucosinolate were increased. The highest oil content (45.59%) was in normal irrigation and normal cultivation, And the lowest (42.16%) was observed in irrigation withholding in pod formation stage and delayed cultivation. The highest content of proline (21.59 mg.g. Fw) was observed in normal cultivation and GKH3705 cultivar. The cultivar of GKH3705 was the most appropriate in terms of yield and its components, oil content, saturated and unsaturated fatty acids and glucosinolate of seeds. According to the results, it seems that normal cultivation and GKH3705 cultivar under without stress and drought stress can be recommended as the best treatment for the benefit of rapeseed production in the Karaj region.

According to the results of this experiment, the most suitable planting date for the studied cultivars of canola is 20th of October in Karaj area. Among the cultivars under study, GKH3705 also produced the highest grain yield in normal and delayed planting, as well as in normal irrigation and stress conditions. In terms of grain and oil production potential and the composition of unsaturated fatty acids are in the optimum level.

Drought is the major abiotic factor limiting crop production over the world. The present study aimed to evaluate the effects of brassinosteroid on yield and its components of seven wheat genotypes under water deficit conditions. A split-split plot design based on a randomized complete block design with three replications in the research filed of Seed and Plant Improvement Institute in Karaj at 2017-2018 and 2018-2019 cropping seasons. The main plots were two levels of water deficit (normal irrigation and irrigation cut off from flowering stage), subplots were four concentrations of brassinosteroid (0, 0.25, 0.625 and 1 mg.l-1) and sub-sub plots were allocated to six wheat genotypes (3737, 4228, 3506, 4056, 2853, Mehrgan and Parsi). The result revealed that irrigation cut off in flowering stage caused reduction in the mean values of the characters.  Also, results demonstrated that the brassinosteroid partially offset the adverse impacts of water deficit, which, application of 0.625 mg.l-1 was more effective than the other levels.  The highest grain yield (1.63 kg m-2) was obtained in 4228 genotype under normal conditions and application of 0.625 mg.l-1 of brassinosteroid, whereas the lowest (0.33 kg m-2) was observed in Parsi under water deficit and whiteout brassinosteroid.  Based on principal components analysis the three first components explained 92 of total variance among the genotypes.  According to the results of present study brassinosteroid partially offset the adverse impacts of water deficit and caused increasing in wheat yield.  Also, the results suggested that 4228 genotype can be a candidate for future wheat breeding programs to produce water deficit tolerant varieties with proper yield.

One of the biophysical methods of seed priming is seed pretreatment with ultrasonic wave. Continuous ultrasonic pulses increase the permeability of seeds shells, accelerate the absorption of water and increase the temperature of the tissues. Increase in turgescence rate and tissues temperature of the seeds treated with ultrasonic wave may be associated with accelerated changes in seed metabolism. Germination of Echinacea purpurea seeds is weak and irregular, which is caused by seed dormancy, so in order to investigation the effect of ultrasound waves on germination, some germination enzymes and biochemical treatiesof coneflower (Echinacea purpureaL.)seeds, in 2017, an experiment was conducted as completely randomized design with 5 treatments and 4 replications in Agriculture Faculty of Shahrood University of Technology. Experimental treatments consisted of ultrasound waves at 0, 10, 15, 20 and 25 minutes with ultrasonic device with a constant power of 50 watts at 25°C. The results of analysis of variance showed that ultrasound treatment showed a significant effect on measured traits. Ultrasound waves increased the activity of α-amylase, protease, alcohol dehydrogenase, glucose 6-phosphate dehydrogenase and increased total protein and soluble sugar concentrations in most treatments than control. By increasing alpha-amylase, protease, alcohol dehydrogenase, anginas and glucose 6-phosphate dehydrogenase activity increased germination percentage, germination rate and seedling dry weight. In most traits, the duration of 15 minutes of treatment with ultrasonic waves showed the highest enzymes activity and germination indexes, So 15 min ultrasonic wave at 25℃ and 50 watt power for improving germination and germination treats in coneflower seeds suggested

Water deficit has been the major contributor to the decline in plant yield. Soil amendment and certain hormonal agents are some strategies applied to mitigate the adverse effects of drought stress. The purpose of this study was to investigate the effects of one soil modifier and one growth regulator on some physiological and morphological characteristics of Borago officinalis L. under water deficit conditions. The experiment was implemented as a split-factorial in a randomized complete block design with four replications at the research farm of Agriculture Faculty of Shahroud University of Technology, Iran during 2017- 2018. The main plots consisted of three levels of irrigation (usual irrigation every five days, irrigation every 10 and 15 days) and sub-plots consisted of biochar at three levels (0, 5 and 10 t ha-1) and salicylic acid at two levels (0 and 0.5 mM). Based on the results, biochar, salicylic acid, and water deficit factors affected the number of flowering stems, number of stems, stem height, the amount of chlorophylls a and b, total chlorophyll, and carotenoids significantly. Interactions between salicylic acid and water deficit levels had the most effects on carotenoids and chlorophyll b. Triple interaction of factors also affected the total dry weight, number of flowering stems, the number of stems, stem height, and chlorophyll b. Generally, water deficit stress decreased the amount of photosynthetic pigments and leaf growth indices of European borage compared to control, and salicylic acid and biochar reduced the negative effects on the amount of photosynthetic pigments. Therefore, the use of biochar as a soil modifier and salicylic acid as a growth regulator seems to be useful in ameliorating some of the negative effects of water stress on Borago officinalis.

Salicylic acid and jasmonates (chemical elicitors) are considered as key signaling compounds in induction process, which leads to accumulate of secondary metabolites. External uses of these compounds cause to induce pseudo stress in plants and excites defensive replies in plants, in response to induction of oxidative stress, the plant increases amount of antioxidant genes expression and increase enzymatic activity and non-enzymatic anti oxidants concentration (they often have a medicinal aspect).

The present study investigated the effects of jasmonic acid and salicylic acid on hydrogen peroxide content, electrical lockage, GPX, GST and PAL activity, total phenol, flavonoid and anthocyanin changing in Stevia rebaudiana bertoni under field conditions. The experiment arranged as a randomized complete block design with 12 treatments and three replications in 2015-2016 at Amol city in Mazandaran Province in Iran. Experimental treatments were spraying by different concentration of jasmonic acid, salicylic acid and components of jasmonic acid- salicylic acid. Foliar application started after plant establishment in vegetative phase. Each experimental plot was 2 m× 3 m consisting 10 rows with 30 cm row spaces and seedling transplanted on 15 May. At the end of foliar application, sampling was done for the measuring. Sampling for biochemical analyses from second fully developed leaf was done and freezed in liquid nitrogen, then quickly carried out to laboratory.

The analysis of variance showed that different concentration of jasmonic acid and salicylic acid and spraying both of them in 7-day intervals appeared to be effective (with 99% confidence) on studied traits (data not shown). Spraying with jasmonic and salicylic acid increased hydrogen peroxide content in 9 treatments compared to the control. The highest amount of hydrogen peroxide content in compounds treatment 20 ????M JA -1 mM SA with mean of 5.46 ????mol in fresh weight observed. Plant in response to jasmonic and salicylic acid spraying increased GPX activity in 10 treatments and GST activity in 7 treatments compared to the control and follow them electrical lockage in most treatments (10) was lower than control. The highest amount of GPX activity in treatments 5 ????MJA and 5 ????MJA with average of 0.11 ????molmin-1g-1 FW observed. The highest amount of GST activity was obtained from treatments of 0.5 mM SA -5 ????M JA and 1 mM SA with average of 0.35 ????molmin-1g-1 FW. The PAL enzyme activity (the first enzyme in phenyl proponed compounds biosynthesis pathway) in 10 treatment increased. The highest amount of PAL activity was in compounds treatment of 50 ????M JA -1 mM SA with average of 1140 ????mol cynamic acid mg-1 protein min-1. The PAL enzyme activity had correlation with hydrogen peroxide concentration and GST activity.  The PAL enzyme initiates a phenylpropanoid route that converts L-phenylalanine to trans-cyanamide acid deamination. The PAL enzyme can consider as an antioxidant enzyme because it has the role of depositing oxygen radicals through phenolic compounds. Spraying increased total phenol content in 8 treatments compared to the control. The highest amount of total phenol content was observed in compounds treatment of 20 ????M JA -1 mM SA with mean of 423.7 mgg-1 FW. Spraying with jasmonic acid and salicylic acid increased flavonoid concentration in 9 treatments compared to the control. The highest amount of flavonoid content was in treatment of 20 ????M JA -1 mM SA with mean of 110 mgg-1 FW. Spraying increased anthocyanin concentration in 6 treatments compared to the control. Anthocyanins are the most important group of natural pigments after chlorophyll that are involved in light protection. The noticeable point is that in most treatment PAL enzyme activity, total phenol, flavonoid and anthocyanin content in compound treatment increased.

The highest amount of total phenol and flavonoid content observed in compounds treatment of 20 ????M JA -1 mM SA and anthocyanin increased in total compounds treatment and using PAL enzyme activity had correlation and significant effect (data not shown). Stevia has anti–cancer effect, anti-blood glucose effect and anti-cardiovascular effect. This effects for the existence phenolic compounds in stevia such that had the ability to remove ROS, so increasing phenolic component by jasmonic acid and salicylic acid spraying in stevia was useful.

To investigate the effect of exogenous brassinosteroid application on grain yield, catalase, chlorophyll content, membrane mtability index and gene expression of some genes involving in brassinosteroid signaling pathway (BES1 and BRI1) under drought stress, a split-split plot on randomized complete block design with three replications was conducted at the experimental field of Seed and Plant Improvement Institute, Karaj, Iran in 2019. The main factor was two irrigation treatments (normal irrigation and water holding after 50% flowering stage), the subplots were four concentrations of brassinosteroid (0, 0.25, 0.625 and 1 mg/l) and seven genotypes (Mehregan, Paris, 2858, 3505, 3737, 4228 and 4056) were considered as sub-sub plots. Samples were taken at 30 days after 50% flowering stage (zadoks 89) from flag leaves. The results showed that drought stress significantly reduced grain yield, chlorophyll content, membrane stability index and increased catalase in all genotypes. Genotype 4228 was identified as the most tolerant genotype among unknown wheat genotypes based on grian yield, chlorophyll content, membrane stability index and catalase. Also, the result revealed that applied epibrassinolide could reduce the destructive effects of drought stress on wheat thus grain yield was enhanced under drought stress in all genotypes by increasing the aforementioned traits. Forethermore, grain yield was increased by rising the epibrasinolide concentration. Gene expression pattern of TaBES1 and TaBRI1 using real-time PCR showed that although brassinosteroid enhances drought tolerance in wheat but its signaling pathway is different from the BRI1 signaling pathway.

Food security in parallel with the preservation of environment and natural resources, has become a critical issue in the world. Wheat as the main food for human has allocated the high cultivation area each year in the world and in Iran as well. Agricultural systems due to the consumption of fossil fuels and chemical output has introduced as the biggest consumers of energy and natural resources, also it has contributed serious role in bio environment problems (Roy et al., 2005). The environment seeks a system to provide the necessities of current generation,   as well as prevention of resources s for the next generation.  To study the positive and negative effects of cropping systems, the researchers have introduced multiple methods to study bio environment effects. In this regard, one of the best method is the life cycle assessment (LCA). Management method plays critical role in bio environment effects of cropping systems. LCA study of wheat frequency has conducted in Iran and the world. This study compares two conventional and progressive cropping management systems of winter wheat in Mayamey farms in Shahrood city using the life cycle assessment method.

Life cycle assessment (LCA) was conducted using data of winter wheat fields in Mayamey, (Shahrood city) with two conventional and progressive management methods.  LCA includes four steps  (purpose definition, study practice area, assessment the effect of life cycle ,results integration and interpretation). At the first step,  the functional unit of one ton was determined,  then data was classified, normalized and weighted, finally the indices of global warming, eutrophication of agro ecology,  discharge potential for possible recyclable resources , poisoning and land use were analyzed .

The ecology index resulted from LCA method in progressive management is higher than conventional management.  The emission rate of effective greenhouse gases for global heating potential index in the studied cropping systems is 461.98, 309.48 units equal to CO2 kg for the conventional and progressive management of wheat fields respectively. Potential of acidification index in agroecosystems with different conventional and progressive managements are 4.43 and 3.13 units equal to SO2 kg per functional unit. Results shown that the bioenvironment effects of  eutrophication potential in  dry systems in winter wheat production was 33.35 in conventional agroecosystem and 23.75 for progressive agroecosystem per NOx kg dissemination . Results of discharge potential for possible recyclable resources shown the highest gas use is 2.54 m3.ha-1 in conventional agroecosystem and 1.53 m3.ha-1 in progressive agroecosystem respectively, while other non-renewable sources such as rock phosphate and potash were 6.75 and 3.39 in conventional afro ecology respectively and this amount was 5.25 for phosphate and 2.43 for potash in progressive agroecosystem. The study indicated that in conventional managed farm the poisoning effects of heavy metals cadmium for human and dry agroecosystem were 0.00033 and 1.40200, respectively, where it was 0.00030 and 1.28501 in agroecosystem for progressive management. The occupied land for each ton of wheat was computed as 1840 for progressive management and 1493.3 m3 for conventional management.

Results of LCA shown that phosphate resources depletion  for discharge potential index of renewable resources and eutrophication of dry agroecosystem has more bioenvironment effects than other  indices, also the results of both conventional and progressive management of winter wheat agroecosystem shown that  the bio environment effects of progressive management has been more than the conventional management, while it is shown higher yield and the higher use of inputs don't mean higher yield necessarily. Results may be important for farmers and agriculture managers in the region in case of a sustainable management procedure.

To evaluate the effects of endophyte symbiosis and spraying of spermidine on chlorophyll fluorescence and photosynthetic pigments of stevia (Stevia rebaudiana Bertoni) medicinal plant under salt stress conditions, a factorial experiment was conducted based on completely randomized design with three replicates. The treatments consisted of salinity in three levels (0, 6 and 12 dS.m-1), fungal symbiosis treatments including four levels: non-inoculated (control), inoculation with Piriformospora indica (Pi), at Trichoderma virens (Trich) and co-inoculation of two fungi (Pi+Trich) and spraying of spermidine in three levels (0, 0.75 and 1.5 mM). Seedlings of stevia after inoculation with fungi were irrigated with tap water until the end of vegetative stage and then irrigated with saline water treatments containing mixture of distilled and Caspian Sea water. The spermidine was foliarly sprayed one week before salinity stress. The results showed that the inoculation of endophyte fungi had a positive effect on Fm, Fv and Fv/Fm. The most increase of these parameters recorded when two fungi (Pi+Trich) were coinoculated. Also, fungi inoculation increased Y(II) while decreased Y(NPQ) and Y(NO) at different salinity levels. Fungal inoculation particularly Pi+Trich and spermidine application with 0.75 mM markedly increased Fm, Fv and Fv/Fm. Also, in all levels of salt stress inoculation with fungi as well as interaction of fungi and spermidine increased chlorophyll a content. In general, inoculation of endophytic fungi particularly co-inoculation of P. indica and T. virens, improved the chlorophyll fluorescence parameters and adjusted adverse effects of salinity. Also, the spermidine (especially at the rate of 0.75 mM) induced salt stress tolerance in stevia plant and showed synergetic effects with endophytic fungi in terms of the mentioned parameters.

Rapid, uniform and complete germination of seeds causes optimum seedling emergence and early growth. Early optimum growth results in more solar radiation interception and increases yield. The germination of purple coneflower is low and non-uniform. One of the reasons of low germination is low permeability of internal membranes. Seed priming is very simple procedures which can improve germination and seedling establishment. One of the biophysical ways of seed priming is pretreatment of seeds with ultrasound. Continuing wave-resulted beating increases the permeability and enhances water absorption and temperature. The increased imbibition rate accompanies with speedy changes in seed metabolism. Imbibition triggers hydrolytic enzymes activity for synthesis of main sugars, amino acids and fatty acids. These compounds are transferred to embryo axis and used for production of new materials. This experiment was aimed at studying the ultrasonic wave’s effect on germination, activity of alpha amylase, sugars, chlorophyll, hydrogen peroxide, and some antioxidant enzymes in germination and seedling stages of purple coneflower.

In 2016-2017, an experiment was conducted as completely randomized design with 5 treatments and 4 replications in Agriculture Faculty of Shahrood University of Technology. Treatments were irradiation durations of 0, 10, 15, 20 and 25 minutes by ultrasonication device. The measured traits were maximum germination, germination rate, seed reserve use efficiency, seedling dry weight, alpha amylase, total sugar, reducing sugars, non-reducing sugars, ratio of non-reducing to reducing sugars, electrical conductivity, hydrogen peroxide, catalase, guaiacol peroxidase, polyphenol oxidase, glutathione -S transferase, and chlorophyll a and b.

The analysis of variance results showed that pretreatment of seeds with ultrasonic waves affected significantly all studied traits. The highest amount of germination percent and seedling dry weight was obtained from seeds irradiated for 15 minutes. The maximum germination rate and seed reserve utilization was for irradiation durations of 15 and 25 minutes. All irradiation levels increased the activity of alpha amylase, total sugar, non-reducing sugars compared to control. The highest amount of non-reducing sugars was found for 25. Irradiation enhanced electrical conductivity and hydrogen peroxide in comparison with control. For most cases, all irradiation durations increased antioxidant enzymes and consequently enhanced amount of chlorophyll a and b in comparison with control.

The irradiation increased seed vigor. The best irradiation duration, by which both germination and seed biochemical properties were increased, was 15 minutes. Naturally, with increasing germination rate and germination percent in farms, the utilization of growth resources like water and nutrients gets improved. Generally, ultrasonic waves with promoting activity of germination enzymes, biochemical properties and germination indices can be used as stimulator of germination, accelerator of germination of low-germinating seeds.

Biochar which is producing by thermal decomposition of organic material under limited supply of oxygen and relatively low temperatures, produces with the intent to be applied as a technique for improving soil properties. Adding biochar to the soils boosts soil fertility and improves the porosity, moisture, cation exchange capacity, pH, and development and reproduction of microbes in the long term. Research indicated that biochar potentially enhanced soil water holding capacity. This infers that soil amendment with biochar may improve crop productivity by retaining more water from rainfall in arid regions and reduce the frequency/amount of irrigation water in irrigated regions. Currently there is no logical method to increase precipitation during drought periods, therefore using drought resistance cultivars and appropriate agricultural techniques are the best solution to deal with this problem. Using soil amendments like biochar to increase water retention has been considered for a long time to decrease the drought effects. This study aimed to assess the effect of biochar on growth and yield of fenugreek landraces under deficit irrigation.

To assess the effect of biochar on growth and yield of fenugreek landraces under deficit irrigation, a field experiment was conducted in 2015 at the Agricultural Biotechnology Research Institute of Iran, Karaj, Iran. Six branched fenugreek landraces including Dezful, Shushtar, Ardestan, Rehnan, Yazd, and KhomeyniShahr were treated by biochar application and non-application under 2 different irrigation intervals. A split plot factorial experiment in a randomized complete block design with three replications was used. Each plot had the size of 4 m × 2.5 m with a plant density of 40 plant m-2. Biochar was derived from rice husk at 500°C in an oxygen depleted environment. Biochar application rate was calculated based on bulk density for the 30 cm layer of the soil (8:92 v/v) and added to the top layer of the soil. Increasing irrigation interval from 4 to 8 days applied from 50% of flowering stage. Seeds were sown on May 10th and mature plants were harvested on November 11th. Plant height, number of main and secondary branches, as well as yield and yield components were measured. Statistical analyses were done using SAS (9.2) software.

According to the results, assessed traits were not significantly affected by triple interaction effect of treatments and also double interaction effect of landrace and biochar. But biochar application increased the number of main and secondary branches, 100-seed weight, and seed yield on 4- days irrigation interval by 19.75, 18.13, 17.54, and 24.33%, respectively and on 8-days irrigation interval by 2.61, 19.52, 8.67, and 26.66%, respectively. Moreover, increasing irrigation interval decreased plant height by 22.42, 22.01, 27.23, 13.66, 27.13, 26.62%; the number of main branches by 6.18, 7.92, 31.84, 16.66, 24.22%, 32.97%; the number of secondary branches by 40.54, 39.09, 40.99, 39.83, 40.89, 40.88%; 100-seed weight by 20.43, 8.70, 17.22, 26.98, 26.44, 23.11%; and seed yield by 61.20, 47.55, 50.12, 44.71, 38.44, 46.24% in Dezful, Shushtar, Ardestan, Rehnan, Yazd, and KhomeyniShahr landraces, respectively. However, the number of pods plant-1 and seeds pod-1 were not significantly affected by interaction effects of treatments. Several studies showed the reduction of crop growth and production under water deficit. Baradaran et al. (2013) also indicated increase in irrigation intervals decreased plant height, the number of pods, the number of seeds pod-1, and thousand-seed weight in fenugreek. This results are due to increase in allocation of photosynthetic material to roots than shoot resulting in smaller plants with less leaf area as a key factor in receiving solar radiation, water and energy exchange, and biomass production. Several studies reported increased water holding capacity by biochar addition because of its high adsorption capacity and porous structure. Akhtar et al. (2014) also reported that addition of biochar increased the soil moisture content in deficit irrigation which consequently improved physiology, yield and quality of tomato compared with non-biochar control.

In conclusion, adding biochar at a concentration of 7-8% to a loamy soil reduced the effect of water deficit on fenugreek growth and seed yield. Biochar increase seed yield by increasing seed weight rather than the number of pods plant-1 and seeds pod-1.

Conventional tillage systems disturb the soil in the long term and obstruct farmland sustainability. Hence, adoption of conservation tillage systems, for example no tillage and reduced tillage has been widely accepted in the last two decades.
The use of chemical fertilizers has increased in intensive farming systems, but this brings with environmental problems. Nowadays, due to the problems of chemical fertilizers, the use of organic fertilizers such as manure and biochar has been more prevalent in agriculture. Biochar is the product of incomplete combustion of biomass in the absence of oxygen. Its presence in the soil is reported to improve physical and chemical properties and crop yield. In order to evaluate the effect of nutrition management on yield and yield components of corn (Zea mays L.) under different tillage systems, a field experiment was carried out at research farm of Shahrood University of Technology in 2015. The experiment was conducted as a split plot arranged in a randomized complete block design with three replications. The main plots were tillage systems (conventional tillage and reduced tillage) and subplots were control, chemical fertilizer (300 kg.ha-1 urea and 100 kg.ha-1 triple superphosphate), manure (20 t.ha-1), biochar (20 t.ha-1), chemical fertilizer + manure (150 kg.ha-1 urea and 50 kg.ha-1 triple superphosphate and 10 t.ha-1 of manure), chemical fertilizer + biochar (150 kg.ha-1 urea and 50 kg.ha-1 triple superphosphate and 20 t.ha-1 biochar) and manure + biochar (20 t.ha-1 biochar and 10 t.ha-1 of manure). After adding manure, biochar and triple superphosphate, corn was planted on 10 days and urea was used in stages three. At full maturity 10 plants were randomly selected and the biological yield, grain yield, 100-grain weight, ear weight, number of row per ear, number of grains per row, ear length, ear diameter, height and stem diameter were measured. The results showed that the effect of tillage systems and the interaction of tillage systems and nutrient management were not significant on any of the measured traits. Tillage systems affect yield mainly by altering water and nitrate content in soil. The water content and nitrate concentration in the soil had no significant difference between tillage systems (data not shown). As well as tillage systems are site-specific, so the degree of their success depends on soil, climate and management practices. The nutrition management had significant effect on grain nutrients, grain protein, ear characteristics, 100-grain weight, biological yield, grain yield and harvest index. The highest and lowest grain nitrogen, ear weight, biological yield and grain yield were obtained in chemical fertilizer and control, respectively. The chemical fertilizer + manure increased grain nitrogen, ear weight, biological yield and grain yield 13.89, 56.19, 47.04 and 60.41 percent compared to the control, respectively. As well as chemical fertilizer + biochar increased grain nitrogen, ear weight, biological yield and grain yield compared to control 14.81, 52.78, 42.69 and 56.32 percent, respectively. Crops respond to nitrogen fertilization mainly by increasing aboveground and root biomass production. As a result of increasing nitrogen doses, the photosynthetic activity, leaf area index (LAI) and leaf area density (LAD) increase. Providing organic matter and nutrients create better conditions for photosynthesis and plant growth. The increased maize yield in biochar amended soil could be attributed to increased nutrient availability and to improved soil physical properties indicated by decreased soil bulk density. Based on results, the effect of nutrition management was significant on height, stem diameter, grain nutrients, grain protein, ear characteristics, 100-grain weight, biological yield, grain yield and harvest index. Maximum and minimum of stem diameter, grain nitrogen, grain protein, ear characteristics, 100-grain weight, biological yield, grain yield and harvest index were obtained in chemical and control, respectively. Although using of chemical fertilizer had the highest amount of traits, it had no significant difference with chemical fertilizer + manure and chemical fertilizer + biochar. Also, there were no significant effect between conventional tillage and reduced tillage. Therefore, due to the excessive use of nitrogen fertilizer and also due to the negative effects of conventional tillage on the physical, chemical and biological properties of soil, it can be concluded that use of reduced tillage and chemical fertilizer + manure and chemical fertilizer + biochar for corn production is recommended for similar conditions with the study area to reduce both chemical fertilizer and environmental pollution.