جستجوی مقالات مرتبط با کلیدواژه « sesame » در نشریات گروه « زراعت »

Sesame (Sesamum indicum L.) is an annual plant belonging to the Pedaliaceae family with a long agricultural history, which is mostly grown as an oil crop in tropical regions and is resistant to drought stress. This Crop is grown in Iran on an area of about 42,000 hectares with an average yield of 690 kg per hectare. The knowledge of the relationship between crop traits and performance is of great importance in agronomic research. Selecting the desired cultivars and determining the cause and effect relationships between traits allows the breeder to select the most appropriate plant traits to increase yield.

In this experiment, 12 sesame genotypes including commercial, local cultivars and line were evaluated. The experiment was conducted in the research farm of the Faculty of Agriculture of Persian Gulf University, Bushehr, located eight kilometers southeast of Barazjan city. The agricultural climate of the region has very hot, dry and long summers. The experiment was conducted in a randomized block design with three replications. Principal Components Analysis and Factors Analysis were used for reduction of data dimensions and better and easier interpretation of data and determination of hidden factors affecting performance.

All studied traits were statistically different. The highest amount of 1000 seed weight belongs to Behbahan (3.4 gr), Abadan (3.36 gr) and Dashtestan 2 (3.3 gr) landraces. The highest number of seeds per capsule, Plant height, number of branches and number of fertile branches were observed in Abadan, Dashtestan 5, Dashtestan 2 and (Barazjan and Abadan) genotypes, respectively. Abpakhsh, Ardakan Yazd, Barazjan and Dashtestan 5 landraces had a number of days to maturity than the others. This trait had high heritability and low genetic advances. In order to reduce the dimensions of the data, better and easier interpretation of them and to determine the hidden factors, Factor Analysis was done with varimax rotation. Three factors were extracted. According to the amount of influential traits in each factor, the first, and second factors were named yield potential and morphologic, phenology factors, respectively. In general, it can be concluded from the results that the yield and phonological traits can be important indicators for the evaluation and selection of sesame cultivars. According the Principal Components Analysis based on the correlation matrix ,76% of the total variations were estimated by three main components. As a result, it can be said that the selection based on the first component will lead to the genotypes with high yield, and the selection based on the second component will lead to the genotypes with late maturity characteristics. In order to determine the grouping of genotypes, cluster analysis was used and based on the three indices RMSSTD, False T2 and False F, four distinct groups were recognized. The results of cluster analysis did not show any relationship between the geographic and genetic distribution of genotypes.

The results showed that the studied genotypes were different according the studied traits. Because selection of genotypes with high yield is considered important in plant breeding programs, genetic parameters were calculated. The high level of genetic improvement and heritability for the traits number of capsules per plant, number of seeds per capsule, seed yield, number of fertile branches and harvest index indicate the possibility of selection with an intensity of 5% in the next generation of selection. The results of Factor Analysis indicated the importance of yield and phenology traits in the selection of desirable genotypes in sesame.

Since there is no information available regarding crop management, including proper planting arrangement and optimal planting density, of the imported shattering tolerant sesame genotypes, field experiments were carried out in research fields of Seed and Plant Improvement Institute, Karaj, and Khorasan Razavi Agricultural and Natural Resources Research Center, Mashhad, Iran, in 2019 and 2020. The effect of experimental factors including; 30, 45 and 60 cm inter row spacing, and 5, 8, 11 and 14 cm intra row spacing were evaluated as split blocks (strips) arrangements in randomized complete block design with three replications. The results showed that there was reduction in number of sub-branches in both locations due to reduction in inter row spacing and intra row spacing. On the other hand, the reduction in plant density m-2 increased the number of capsules plant-1 and seed number capsule-1. The highest seed yield (1342 and 604 kg ha-1 in Karaj and Mashhad, respectively) obtained from the 45 × 8 and 45 × 11 planting arrangement in Karaj and Mashhad, respectively. Generally, the results indicated that there is an optimal planting arrangement and planting density for each location. Therefore, due to increased competition between plants in high plant density and lack of proper utilization of resources in low plant density, it would not be possible to attain the highest yield potential of shattering tolerant sesame genotype in high and low plant density.

One of the methods that has been used in recent years to deal with dehydration and drought stress in many plants is the use of root symbiotic fungi (mycorrhiza). Ecological and physiological studies have shown that mycorrhizal symbiosis often results in better absorption of water and nutrients from the soil. Due to the importance of oilseeds and especially sesame, the study of commercial cultivars in terms of genetic variation, phenotypic components and heritability of traits is important. Sesame due to its high oil content (52-42 Percentage) and its proper quality (low cholesterol and the presence of some antioxidants) play an important role in human health and on the other hand the plant tolerates dehydration and drought stress. Currently, water stress is the most important and common factor in reducing yield in arid and semi-arid regions. High heritability for a trait indicates that the major part of phenotypic variance is due to genetic variance, while in low heritability, genetic factors have a smaller share in phototypic diversity. The aim of this study was to estimate the variance components and heritability of grain yield and related traits in 8 commercial sesame cultivars under different irrigation conditions.

In order to investigate the genetic diversity and the heritability of grain yield and yield components in sesame, 8 commercial cultivars were studied in three separate experiments using factorial split plot based on randomized block complete design with three replications in research field of Agricultural Research Center, West-Azerbaijan in 2015-2016 and 2016-2017 cropping seasons. The main plots (factor A and B) consisted of three different levels of irrigations (normal irrigation: irrigation after 70 mm evapotraspiration of crop or ETc, moderate drought stress: irrigation after 90 mm ETc and severe drought stress: irrigation after 110 mm ETc) and factor B included three levels: two species of mycorrhiza fungi Glomus mosseae, Glomus intraradices and non-inoculated (control). Sub plots (factor C) consisted of eight commercial cultivars of sesame.

The results of analysis of variance showed that the effect of environment, genotype and the interaction of environment × genotype on most of the studied traits were significant. In optimal irrigation regimes, moderate and severe drought stress under inoculation and non-inoculation conditions with mycorrhiza, the highest genetic variance was observed in biological yield, number of seeds per square meter and seed yield, respectively. The highest heritability in optimum irrigation conditions without mycorrhiza inoculation of traits (seed yield and number of grains per capsule), in optimum irrigation conditions and inoculation with mycorrhiza (both two species) (seed yield and 1000 seed weight), in moderate drought stress conditions and no inoculation with mycorrhiza (seed yield, 1000 seed weight and number of seeds per capsule), under moderate drought stress and inoculation with mycorrhiza G. mosseae (1000 seed weight and number of grains per capsule), under moderate stress conditions and inoculation with mycorrhiza G. intradices (seed yield, 1000 seed weight and number of grains per capsule), under severe drought stress conditions and without inoculation with mycorrhiza (stem diameter and 1000 seed weight), under severe drought stress conditions and inoculation with mycorrhiza G. mosseae (stem diameter, number of seeds per capsule and number of seeds per square meter) and in conditions of severe drought stress and inoculation with mycorrhiza G. intraradices (stem diameter, number of seeds per square meter and 1000 seed weight) were observed. Seed yield, biological yield and seed yield components had high genetic gain and genetic advance in all three different irrigation conditions. Among the components of grain yield, considering that the heritability of number of seeds per capsule and 1000 seed weight in all three different irrigation conditions is higher compared to the number of capsules per plant, so selection through number of seeds per capsule and 1000 seed weight to increase seed yield will be more efficient.

Therefore, commercial sesame cultivars that have more seeds per capsule and a 1000 seed weight can be used in breeding programs to produce cultivars with high seed yield. According to the information of this study, only general heritability can be calculated, but since many studies on commercial sesame cultivars in interaction with different conditions of irrigation and inoculation and non-inoculation with mycorrhiza have not been done, so this study can useful for researchers.

Sesame is an important oilseed in which contains rich source of oil, protein, phosphorus and calcium. Drought is considered as the most obvious environmental factors in reducing the growth and yield of sesame in arid and semi-arid areas. Due to high economic importance of sesame from one hand, and high efficiency of priming and its cheapness to alleviate adverse effect of drought stress from other hand, the aim of present study was to evaluate drought stress and various priming methods on yield component and physiological features of three different sesames.

The study was conducted for two years in spilt plot factorial design with three replications in the farm of research center of Bushehr city. The main factor consisted drought stress in three levels of drought stress included irrigation after drainage of 45% FC (control or without stress), irrigation after drainage of 65% FC (mild stress) and irrigation after drainage of 85% FC (severe stress), five priming treatments included control (without priming), hydropriming, zinc sulphate, potassium sulphate and salicylic acid (SA) in three sesame verities (Oltan, Dararb 14, Karaj) were evaluated. Various yield and physiologic parameters such as chlorophyll content, soluble sugar and some antioxidant enzymes activities were investigated.

According to the results, with increasing stress level, 1000 seed weight, harvest index, seed yield, capsule number, total chlorophyll, leaf area index, relative water content have shown decreasing while proline and soluble sugar have increased. Furthermore, it was found that priming had a significant impact on yield and physiological traits. The highest yield, harvest index and 1000 seed weight were respectively found in priming with SA 1153, 25.7 and 2.66 kilogram per hectare while the least were respectively reported in control treatment (without priming) 968, 23.8 and 2.51. Also Karaj and Oltan, respectively have shown the highest and the least seed yield 1269 and 889 kilogram per hectare. The highest proline content (1.29 mg/g FW) in Karaj variety and the lowest amount (1.17 mg/g FW) in Oltan veriety were shown. However, the highest soluble content (1.03 mg/g FW) in Oltan genotype and the least one (0.97 mg/g FW) in Karaj were reported. Also, the highest and lowest amount of relative water content and total chlorophyll were in Karaj and Oltan verities, respectively. Moreover, the investigated cultivars had shown different responses in physiological traits. In most yield traits, cultivar Karaj and Oltan showed the highest and least yield features.

Drought stress caused less sesame yield, but different genotypes reaction to stress were not the same. Although, desirable effects of seed priming with Salicylic acid, ZnSO4 and K2SO4, that by maintaining chlorophyll content and finally aid to photosynthesis process, was remarkable. In present research, Karaj verity was more resistant to drought stress. According to SA and zinc roles on photosynthesis, osmolytes synthesis in alleviating adverse effects of drought stress and on the other hand, desirable effect of priming on sesame growth and yield, using SA, zinc sulphate and potassium sulphate for increasing yield in region facing with drought stress are recommended.

Among oilseeds, sesame (Sesamum indicum L.) is known as the queen of oilseeds due to its significant amount of antioxidant compounds, essential amino acids and unsaturated fatty acids. Among the necessary managements to achieve maximum crop production, the selection of cultivar, density and planting pattern could be mentioned. Different sesame cultivars have various growth characteristics (for example, branching) and each of them is suitable for a planting method with a certain density. The aim of this study was to evaluate the planting pattern and suitable density for two sesame cultivars.

In this study, the effect of planting pattern (single or double row(s) on ridges), plant density (20, 30 and 40 plants m-2) and sesame cultivars (Oltan and Naz Tak Shakheh) based on factorial experiment in a randomized complete blocks design were evaluated in three replications during 2019 and 2020 in Karaj region. Plant height, grain yield and yield components, dry matter yield, harvest index and oil percentage and yield were evaluated. Statistical analyzes were performed using SAS software and LSD test was used to compare the main means and slicing was used to compare the means of interactions.

Analysis of variance showed that effect of planting pattern factor on plant height and dry matter yield, plant density factor on all traits (except 1000-seed weight) and cultivar factor on all traits (except harvest index) were significant. Comparison of means showed that the mean of plant height in planting pattern of double rows on ridges (126 cm) was significantly higher. Among the yield components, the number of capsules per plant at densities of 30 and 40 plants m-2 (57 and 60, respectively) were the highest, which were statistically significant compared to the density of 20 plants m-2 (50). The number of seeds per capsule at the density of 20 plants m-2 was the highest (58) which showed a statistically significant difference compared to the other two densities. Among the studied densities, the highest grain yield (993 kg ha-1) was obtained from the density of 40 plants m-2 and the lowest grain yield (798 kg ha-2) was obtained from the density of 20 plants m-2. Among the two studied cultivars, Oltan cultivar had the highest yield and grain yield components which showed a statistically significant difference compared to Naz Tak Shakheh. The highest oil yield was produced by Oltan cultivar in each of the densities of 30 and 40 plants m-2, which statistically did not show a significant difference in planting pattern of single or double row(s) on ridges.

This study showed that Oltan cultivar is recommended in planting pattern of single row on ridges and in density of 30 plants m-2 for Karaj region.

Sesame is an oilseed crop with high resistance to dehydration. This plant with the minimum moisture requirements has a good performance compared to the other crops in the summer. Recognition of high-yielding genotypes under these conditions is one of the priorities of sesame breeding programs. In the current study, 10 promising sesame lines derived from segregating generations that were superiors in the preliminary evaluations were evaluated along with 6 local genotypes in the form of RCBD with 3 replications in the Sistan region during two cropping seasons. Different quantitative and phenological traits were evaluated during the growing periods. ANOVA results indicated significant differences among genotypes for their grain yield, biological yield, plant height and thousand seed weight. Using Duncan's mean comparison method, genotypes 3, 13, 5 and 7 were identified as superior genotypes. The correlation study of the studied traits showed a positive and significant relationship between grain yield and 1000-seed weight. Also, biplot diagram of genotypes distribution on the first two components showed that genotypes 3, 5 and 13 are different from other genotypes in the term of quantitative traits and were considered as the best ones. Cluster analysis for all traits using Ward method also distinguished genotypes 3 and 13 from other genotypes. Additionally, genotypes ranking based on the selection index of ideal genotype (SSIG) revealed genotypes 3 and 13 as high ranking genotypes. Therefore, using different multivariate analysis methods, genotypes 3, 13 and 5 are introduced as desirable yielded genotypes with high compatibility in the Sistan region.

Weed suppression and increased production are objectives of intercropping systems. This study was carried out to investigate the effect of mixed culture on weed suppression, yield and its components of sesame and cowpea. The experiment was arranged in a split plot based on a randomized complete block design with four replications at the research farm of Agriculture and Natural Resources Campus, University of Tehran, during 2019. The main plots included pure sesame culture, pure cowpea culture, 50% sesame: 50% cowpea, 65% sesame: 65% cowpea and 80% sesame: 80% cowpea and sub plots included weed control and no weed control treatments. Results showed that pure sesame culture had the highest weed density and dry weight and there was no significant difference in weed density and dry weight between mixed and pure cowpea cultivars. In the most studied traits, there was a significant difference between weed control and no weed control treatments. Land equivalent ratio (LER) was higher than one in all treatments and was higher in without weeding rather than weeding treatments. The intercropping of 50% sesame: 50% cowpea had the highest LER, in terms of weed control and non-control (1.15 and 1.72, respectively). In general, it is concluded that sesame and cowpea mixture increased the land use efficiency while avoiding weeds, especially compared to pure sesame cultivation.

This study was conducted during summer and winter of 2018- 2019 in the agricultural research field of Shahid Chamran University. Experimental design was split- plot based on RCBD with three replications. The main plot was the type of agricultural system in three levels including conventional (Conv), organic (Org) and sustainable (Sust) (integrated between Conv and Org) and sup- plot was the type of pre- cultivated crop in sequence with wheat including cultivation of mung bean (M- W), corn (C- W), sesame (S- W) and fallow (F- W). Yield quantity (yield and its component) and quality (grain protein), an estimate of photosynthesis matter transfer index of wheat and soil organic carbon (SOC) after one double-cropping were measured. The result showed that the highest (545.04 g/m2) and the lowest (409.28 g/m2) seed yields were obtained in Conv and Org respectively. In contract, with the changing type of system from Conv to Org, grain protein was increased significantly (from 8.3 to 9.6 %). In addition, the highest (535.47 g/m2) yield of wheat was obtained from M- W double cropping. On the other hands the highest remobilization and current photosynthesis matter were obtained in the organic agricultural system with M- W and conventional with M- W double cropping. The situation of SOC showed that the highest (33.18 mg/g) SOC was obtained in the organic agricultural system with C- W double cropping. The reason for improving SOC in the organic and sustainable agricultural system was application of organic matter (compost and vermicompost) and crop residue management. Totally, from the crop ecology point of view, sustainable agricultural method with a sequence of M- W was the most desirable system.

To estimate general combining ability (GCA), specific combining ability (SCA) and genes action in sesame, a 7×7 diallel cross was conducted using randomized complete block design with three replications under non-stress and stress conditions in 2005 and 2006 in research field of faculty of agriculture of Birjand university. Analysis of variance showed significant differences between genotypes. Griffing analysis showed that significant GCA for all traits in non-stress and stress conditions. SCA was significant for all traits, except plant height, height to first capsule and number of capsule, in non-stress conditions. In stress conditions, SCA was also significant for all traits, except plant height, auxiliary branch number and number of capsule plant-1. Hayman analysis of variance showed that additive genetic variance was significant for all traits in both conditions. The dominant genetic variance was significant for all traits, except plant height and height to first capsule, in non-stress conditions. It was also significant for all traits, except plant height, in stress conditions. Inheritance of yield and related traits was relatively high in both conditions. Broad sense heritability varied from 0.51 (plant height) to 0.99 (several traits), and narrow sense heritability varied from 0.27 (harvest index) to 0.99 (number of capsule) in both conditions. The highest (29.2%) and lowest (-9.47%) heterosis relative to mid-parent observed for grain yield in non-stress and harvest index in stress conditions, respectively. The estimated heterosis relative to superior parent was positive (0.03%) only for capsule length in non-stress conditions.

Identification of genotypes adapted to a particular region is of special interest to breeders and plant geneticists. In order to identify adapted genotypes in sesame lines based on multi-trait selection, an experiment was conducted in a completely randomized block design with four replications at Moghan Agricultural Research Station of Ardabil Agricultural and Natural Resources Research and Education Center during the years 2017 and 2018. The genetic materials evaluated in this study were consisted of 14 superior lines from preliminary yield trails of the three different regions evaluated in 2016 (Derived from the management of segregated generations in a pedigree way) and Oltan cultivar as a check. Combined analysis of variance showed that the genotype and genotype × year interaction effects were significant for all of the studied traits. Biplot analysis of sesame genotypes showed that the first two components explained the 55.3% of the total variations of traits. Which-won-where/what polygon pattern based on different traits of sesame genotypes showed that G3 and G8 had the highest yield and yield components such as plant height, number of capsules per plant and oil content, respectively. Based on comparing of genotypes with ideal genotypes biplot, Shukla stability index, superiority index and heat map analysis, genotypes G3, G8 and G9 were better than Oltan cultivar, thus identified as the best genotypes. These genotypes have the potential to be used in research-extension trials for introduction as a new cultivar for cultivation in Moghan region.

Sesame is one of the oldest crops. Ethiopia is commonly accepted as the origin of domestic sesame. Sesame is a diploid (2n = 26) plant that grows as a bush. Sesame has a special place among oil plants due to its high oil content and quality as well as its high oil durability. Drought stress is a condition that cells and tissues are in a state where their inflammation is incomplete. In other words, dehydration occurs when the amount of transpiration exceeds the amount of water absorbed. Drought is one of the most important causes of declining agricultural productivity worldwide. Drought has destructive and detrimental effects on different stages of plant growth and reduces yield and yield components in sesame genotypes. Due to the serious problem of limited water resources and drought and its effect on yield reduction, this study to evaluate drought tolerance of sesame genotypes based on tolerance indices to identify and group sensitive, tolerant and resistant genotypes and select resistant genotypes and identify correlations of related traits. Drought tolerance was performed through field studies.

In order to evaluate the genetic diversity of different sesame genotypes under non-stress and drought stress conditions, an Augmented design was conducted in three blocks on 32 genotypes in the southeastern fields of Bojnourd in 2018. Genotypes used were obtained from Karaj Seed and Plant Breeding Research Institute in the amount of 1.5 grams per sample. In this experiment, one plot of land was allocated to the drought stress environment and the other to the stress-free environment. The distance between these two environments was considered to be five meters so that the humidity of the two adjacent environments did not affect each other. With the onset of stress flowering on the target medium, application and irrigation of the dry stress plot based on 200 mm and the non-stress plot based on 100 mm evaporation from the pan was performed. Cumulative evaporation from the pan determined the arrival time of irrigation in each of the environments. SAS PLUS software for calculating variance analysis, principal component analysis and mean comparison, S-PLUS software for drawing 3D and bipod diagrams, SPSS software for calculating the correlation of traits and correlation of tolerance indices and cluster tolerance analysis, respectively, from EXCEL Action was taken.

The studied genotypes showed a significant difference at the level of 1% probability in terms of traits measured under non-stress and drought stress conditions, which indicated genetic diversity and the possibility of selecting drought tolerant genotypes. Darab 14 genotype with 2344 kg.ha-1 had the highest grain yield and the Markazi genotype with 1148 kg.ha-1 had the lowest grain yield in non-stress conditions. Under drought stress conditions, Darab 14 genotype with 1360 kg.ha-1 had the highest grain yield which showed a 58% decrease compared to non-stress conditions. Also, the lowest grain yield was observed in Pakistani genotype with 624 kg.ha-1, which was 53% less than non-stress conditions. Based on the results, Darab 14 genotype showed the highest values of MP, GMP, TOL and STI tolerance indices and the correlation analysis between yield under stress and non stress conditions with drought tolerance indices also showed that STI, GMP, MP and TOL indices the most suitable indices are for screening sesame genotype. Using three-dimensional diagrams of YS, YP and STI, the genotypes were divided into two groups A and C under drought stress conditions. In order to investigate the correlation between different agronomic traits in comparing the grain yield of genotypes and determine their relationships, a simple correlation was calculated in both non-stress and drought stress environments, which showed a positive and significant correlation between yield and yield components in both conditions.

This study showed that comparison genotypes significant differences in terms of measurable traits in non-stress and drought stress conditions. Using MP, GMP, TOL, SSI and STI indices, genotypes can be separated to a large extent based on stress tolerance. Based on these indices and considering the performance in two environmental conditions Darab 14, Shaban and Yekehsaud is were identified as the most tolerant.

In order to evaluate the yield, agronomic characteristics and response of sesame promising lines to wilting disease using multivariate methods, an experiment was conducted in a randomized complete block design with three replications in 2019. The genetic plant materials evaluated in this study included the superior 20 selected lines along with Oltan as the control cultivar. During the growing season, different traits such as germination percentage, days to flowering, days to maturity, plant height, branching height, first capsule height, number of capsules per plant, capsule length, stem diameter, number of seeds per capsule, number of branches, leaf chlorophyll content, 1000-seed weight and seed yield per hectare were measured. The response of genotypes to fusarium wilt disease was also scored. The results showed that line 20 with 1604 kg/ha had the highest seed yield among the compared genotypes. Evaluation of lines showed that lines 1, 4, 19 and 20 were the most tolerant genotypes to fusarium wilt disease. The most positive and significant correlation was observed between seed yield and number of capsules per plant, leaf chlorophyll content, number of seeds per capsule, plant height, 1000-seed weight, capsule length and germination percentage, but with the number of days to flowering, days to maturity and first capsule height, it was negatively significant. The results of stepwise regression and path analysis of seed yield as a dependent variable and other agronomic traits as independent variables showed that the three traits including number of capsules per plant, number of seed per capsule and stem diameter had the most positive and significant direct effect on yield, respectively. The most indirect effect on seed yield was by the number of seeds per capsule through the number of capsules per plant. Cluster analysis grouped the genotypes into three distinct groups. The first group, including lines 1, 4, 13 and 20, were among the desirable genotypes in most agronomic traits and were well-distinguished from other genotypes by cluster analysis. In general, the results of this study showed that lines 20, 4 and 1 with the highest seed yield per hectare and superior in terms of important agronomic characteristics and tolerant to plant wilting disease, compared to the control cultivar Oltan, were recommended as promising lines in Moghan region.

 of this experiment was to evaluate the response of purple coneflower (Echinacea purpurea Moench) medicinal plant intercropped with sesame (Sesamum indicum L.) to Mazandaran microclimate differences. The experiment was carried out in a randomized complete block design with three replicates in Simorgh and Savadkooh regions of Mazandaran province during growing season of 2015. The treatments consisted of sole cropping of purple coneflower (Pc), 75% Pc+25%sesame (Se), 50% Pc+50% Se, 25% Pc+75% Se and sole cropping of Se. Some indices such as land equivalent ratio (LER) and monetary advantage (MAI) of intercropping and actual yield loss or increases (AYL) and aggressivitty (A) of two plant species were evaluated based on sesame seed yield and purple coneflower biomass. The statistical analysis of experiment data was performed by using SAS software and mean comparison of evaluated traits was done by Duncan multiple rang test at 5% level of probability.

In this current experiment, the purple coneflower sole cropping in the Savadkooh region had the highest economical yield (3631 kg ha-1) with around 17% increases as compared to the Simorgh region. Also, the 75% purple coneflower+25%sesame intercropping had the same economical yield in two regions and the minimum economical yield was belonged to sesame sole cropping in the Savadkooh region (1716 kg ha-1). According to competitive indices of two species, purple coneflower (Apc) and sesame (Ase) at the range of Apc=0.02-0.16 and Ase=0.10-0.26 were the dominant species in the Savadkooh and Simorgh regions, respectively. Regarding to temperature and relative moisture severity decreases in the Savadkooh as compared to the Simorgh region during growth season, purple coneflower had a higher aggressivitty and dry matter accumulation because of the optimum environmental conditions. Furthermore, the highest purple coneflower actual yield index was belonged to 50% Pc+50% Se in the Savadkooh region (AYLpc=0.23) while actual yield loss was observed in 25% Pc+75% Se planting pattern in the Simorgh region (AYLpc=-0.14). Also, the most sesame actual yield index (AYLse=0.26) was belonged to 25% Se +75% Pc intercropping. The results indicated that different intercropping were grouped in the same statistical category and showed up to 7% increases in land equivalent ratio as compared to sole cropping. Also, the 25% Se +75% Pc planting pattern had the highest monetary advantage index (MAI=1823).

In conclusion, results indicated that the intercropping influenced by two regions microclimate differences. Accordingly, sesame and purple coneflower in 25 and 50 proportion in the intercropping had the best competitive potential in the Simorgh and Savadkooh regions, respectively.

Sustainable agriculture, with respecting ecological principles, can increase the efficiency of resources use and provide a longer-term benefit to humans, while providing a balance in the environment. The application of organic fertilizers with a view of replacing or significantly reducing the use of chemical fertilizers increases the quality and quantity of plants yield. Sesame is one of the most important oily and pharmaceutic seeds in agricultural areas, which is due to its high oil and protein content and antioxidant content in food, food supplements, medicine and industry. Therefore, this study was conducted to evaluate the various organic and biological nutrient systems on yield and yield components of sesame under competition and non-competition with weeds.

This experiment was conducted as a split plot in a randomized complete block design in three replications in Sari Agricultural Sciences and Natural Resources University in 2015. The treatments consisted of: competition between plants and weeds (weedy and weed free) as a main factor, and sub factor was fertilizer sources include sheep manure, pigeon manure, vermicompost fertilizer, bio-fertilizer (Nytrukara), sheep manure + biofertilizers, pigeon manure + biofertilizers, vermicompost + biofertilizer, urea fertilizer and control (no fertilizer). Dominant weeds were identified in the field as velvetleaf (Abutilon theophrassti L.), barnyardgrass (Echinochloa crusgalli L.), bermuda grass (Cynodon dactylon) and wild melon (Cucumis melo var. Agrestis).The studied traits included yield and yield components of sesame, weed density and weed biomass and competitive indices.

The results showed that the highest yield per unit area (2992 kg ha-1) was observed in the integrated treatment of sheep manure and Nytrvkara and the maximum harvest index (44 percent) was in integrated treatment of vermicompost and Nytrvkara in weed free condition, while, the lowest ones was at control in weed infestation. Also, nitrogen sources showed significant differences in weed density and biomass compared to control. In examining the ability to withstand competition (AWC), the results showed that the ability to compete with weeds tolerant, pigeon manure treatment had the highest ability to compete with weeds, while, after a pigeon manure, integrated managements enhance performance, as well as increased competitiveness.

Finally, based on the results of this study, it can be concluded that the combined use of fertilizers, with increasing sesame growth and no environmental side effect, reduces dry weight of weeds, reduces weed damage and also reduces the use of herbicides. So, it is a suitable method for the healthy and sustainable production of these products.

Eight sesame genotypes along with Oltan and Darab1 cultivars were evaluated for seed yield and oil biochemical traits using randomized complete block design with there replications under normal and drought stress conditions in Karaj, Iran, in 2014 and 2015. Drought reduced seed yield by 45.1 %, oil content by 2.5%, palmitoleic fatty acid by 24.0%, and increased the antioxidant power of oil by 99.4%, total lignin of oil by 18.9 and seed crude protein by 15.6%. In fact, drought stress had a beneficial effect on seed oil quality. Genotype KC50662 had reasonable yield under two conditions. In addition, its seed oil content was 5.3% higher than cv. Oltan. This genotype had the lowest amount of harmful palmitic fatty acid (8.5%) second next to Oltan cultivar (8.2%). This genotype had more beneficial oleic (47.1%) and palmitoleic (0.09%) fatty acids compared to cv. Oltan (43.1% and 0.07%, respectively). This genotype also had lower level of stearic acid (4.7%), higher level of linoleic acid (42.0%), higher level of lignans (4237 mg kg-1), and lower level of antioxidants power (23.5 µmol L-1) compared to cv. Oltan (5.4%, 38.7%, 3541mg kg-1, and 33.9 µmol L-1, respectively). Tolerance and susceptibility indices could identify genotype KC 50662 as high yielding, and KC 50658, KC 50687 and KC 50983 as tolerant genotypes. In conclusion, genotype KC50662 was identified as superior genotype with high seed yield, in both normal and stress conditions, and oil quality properties.

Salinity has considerable adverse impacts on productivity of agricultural plants. Soil salinity, resulting from natural processes or from crop irrigation with saline water, occurs in many arid and semi-arid regions of the world like Iran. Sesame (Sesamum indicum L.) is one of the pedalitic families (Pedaliaceae) and one of the long-standing cultivated plants. Cultivation areas of sesame in Iran and the world is about 6500 and 42 thousand hectares, respectively. Since our country is located in the dry and semi-arid region of the world, soil salinity and irrigation water are the major problems in the country's agriculture. Another factor limiting the production of the product in warm and dry areas is the warming of the air which is a global phenomenon that results from prolonged greenhouse gas emissions, such as carbon dioxide gas, and the consequence of rising fossil fuels, the destruction of forests and some of the activities that lead to the development of human life. Considering the increasing greenhouse gas emissions and the importance of planting sesame in stressful conditions, this experiment was conducted to evaluate the tolerance of sesame plants under salinity conditions and increase of carbon dioxide. In order to evaluate the effect of different Co2 concentration and salinity on growth and yield of sesame, a trial was arranged as factorial experiment with four replicates based on complete randomized design at Agrotron growth chamber in agronomy and plant breeding Dept. of Vali-e-Asr University of Rafsanjan. The growth media was the soil with the amount of 2 Kg per pot. Treatments were included Co2 concentration at two levels as ambient (380ppm) and elevated (700 ppm) and salinity stress including 0, 4 and 8 ds/m. Results indicated that leaf proline content and soluble sugar content significantly affected by Co2 concentration which is decreased from 0.28 Mmol/gr FW to 0.08 Mmol/gr FW with elevated Co2 concentration from 380 to 700 ppm. The peroxidase, polyphenol oxidase and phenylalanine ammonialaze enzymes were also affected by the interaction of salinity and carbon dioxide. Sodium content significantly decreased in 700 ppm Co2 concentration compare with 380 ppm. In both of Co2 concentrations, K shoot content significantly increased with increased salinity level. The results showed that increasing of carbon dioxide under salinity stress caused a significant decrease in root Na content. The proline and soluble sugar content significantly decreased higher Co2 concentration. Although increased salinity stress showed increased activity of peroxidase and phenylalanine ammonilase, high salinity reduced the shoot potassium content of in the shoot. In general, the results of this study indicate that sesame plant reacts to different levels of carbon dioxide and that these parameters and relationships can be obtained to predict experiments at higher Carbon monoxide concentration.

Crops cannot be sustainably produced by the exclusive use of chemical fertilizers nor can higher crop yield be obtained by using organic manure alone. Sustainable crop production is possible through some approaches such as suitable crop sequence and also the integrated use of organic manure and chemical fertilizers. Therefore, the mail goal of this study is evaluation the effect of crop sequence as double cropping system and integrated chemical and biological fertilizer on quantity and quality yield of wheat and also its soil chemical nutrients. This experiment was conducted at 2015 – 2016 in research field of Shahid Chamran University of Ahvaz. Experimental design was split plot based on RCB with three replications. Main plot was 5 double cropping systems including 1: sunflower- wheat, 2: millet – wheat, 3: maize – wheat, 4: sesame – wheat, 5: mung bean – wheat. Also, sub-plot was 3 fertilizer managements including 1: full chemical fertilizer, 2: full biological fertilizer, 3: integrated biological and chemical fertilizer. Grain yield and yield components of wheat was measured. The SAS software was used to analyses the results and Duncan methods for comparison of means. Both parameters of main ear weight (1/96 gr) and number of grain in ear (31/7) were obtained in planting mung bean before wheat. But, planting of sesame before wheat had lowest main ear weight (1/63 gr). Also, planting millet before wheat had lowest number of ear /m2 (443/6 ear/m2). In addition, characters that basically formed at early growth stage of wheat (e.g. number of ear per m2) had mostly affected by type of crop in rotation in compared than characters which formed at middle of growth stage (e.g. number of grain in ear). Present of mung bean as a legume crop caused a highest main ear weight due to highest grain per ear (31/7 grain/ear). Highest and lowest of all yield components (exception for number of ear per m2) were obtained in full chemical and full biological fertilizer management, respectively, which showed that relaying on full biological fertilizer management will not enough for obtaining the maximum crop yield. In most cases, straw yield had not affected by type of crop which planted before wheat. However, millet – wheat double cropping system had a lowest straw yield (6/22 t/ha). Also, the highest (7/57 t/ha) and lowest (6/61 t/ha) straw yield was belonged to full chemical and biological fertilizer management, respectively. In addition, the highest (0/1 %) and lowest (0/073 %) soil nitrogen was belonged to sequence of sunflower – wheat and sesame – wheat which treated by integrated fertilizer management. Also, present of sunflower, millet, maize and mung bean crops before wheat, caused by higher soil phosphorus in full biological fertilizer management than other fertilizer systems. Both treatments including type of crops before wheat and Fertilizer management had significant effect on wheat grain yield and yield components. Effect of previous crop in double cropping system had changed with change in fertilizer management from chemical to biological form. But, in short period, effect of fertilizer management was more effective than crop rotation. Highest wheat grain yield was obtained in mung bean – wheat double cropping system with and without integrated fertilizer management (i.e. 7/1 and 5/9 t/ha). Also, millet – wheat double cropping system had a lowest (0/051 %) soil nitrogen. Therefore, we concluded that in rotation with legume crops, integrated fertilizer management will better than both full chemical and full biological fertilizer managements.

This experiment was conducted at the Research Farm of Isfahan University of Technology, Najafabad, Iran in 2014 and 2015 to evaluate drought tolerance indices of some sesame (Sesamum indicum L.) genotypes. In this study, 21 sesame genotypes isolated from different local populations along with seven exotic cultivars were evaluated at two irrigation regimes, using a randomized complete block design with two and three replications in the first and second years, respectively. The normal and water deficit irrigation regimes were determined based upon the depletion of 60% and 90% of soil moisture content, respectively. The results showed that the effect of irrigation regimes was significant (p<0.01) on seed yield. Averaged over two-years, mean of seed yield was 2186 kg ha-1 and 1231 kg ha-1 in normal and water deficit irrigation conditions, respectively. Based upon the data of two years, the genotype Shiraz 5 had the highest seed yield in normal irrigation conditions, however, genotypes Markazi 1 and Shiraz 5 had higher seed yield in water deficit condition. Investigation of different indices of tolerance and sensitivity to drought stress (TOL, SSI, STI, MP, GMP, HARM, DRI, SNPI, SSPI and ATI) showed that STI, MP, GMP, HARM and SNPI were more suitable indices to recognize drought tolerant sesame genotypes. Based upon these indices obtained from the data of two years, genotype Shiraz 5 had the highest tolerance and more productivity and genotype China had the highest sensitivity to drought stress with less potential of productivity.

To investigate the effects of summer cultivation of crops on weeds densities and biomass as well as yield and performance of following planted wheat, field studies were carried out in Shavoor Research Station (Ahvaz, Khuzestan) over 3 years (2013-2016) using 5 treatments in a randomized complete block design. Treatments included rice-wheat, corn-wheat, sesame-wheat, mung bean-wheat and fallow-wheat rotations. The crops and weed densities and types had been observed during the year before the experiment, and no herbicides were used in all experiments to understand the pure effects of treatments. The main crop (wheat) was planted after autumn harvesting of above-mentioned crops. Densities and types of weeds were recorded 15 and 30 days after wheat primary tillering stage, and weed dry weights and grain yield were measured at the end of experiment. Results of this study indicated that considering the indices of weeds number and biomass (55-90%) as well as wheat yield (80-220%), wheat might not require to any herbicides after rice cultivation. Moreover, in the grain or forage corn planted fields, herbicide application is declined significantly, due to several and irrigations and frequent tillage. The whole three-years outcome of the experiments demonstrated that summer cultivation of crops might lead to sharp decline in the seed banks of important weeds such as wild oat (Avena ludoviciana), wild barley (Hordeum spantaneum) and some main broad leaf weed.

In order to study the effect of priming on germination and seedling growth of sesame under salinity stress, a factorial experiment was conducted in a completely randomized design in Seed Technology Laboratory of Shahed University in 2016. Factors included priming in three levels (GA3 250 ppm, GA3 500 ppm and potassium nitrate 0.4%) and five levels of salinity (0, 3, 6, 9 and 12 dS/m) in three replicates. Measurement traits included percentage and germination rate, mean germination time, root and shoot length, seedling fresh and dry weight and relative water content. The results showed that priming treatments, salinity stress and their interaction effect on the studied traits had a significant effect. The results of mean interactions showed that the highest percentage and rate of germination were observed in 500 ppm gibberellic acid pretreatment with no salt stress. Salinity stress reduced seed germination traits, growth parameters and relative water content of sesame seed. Application of gibberellic acid and potassium nitrate pre-treatments improved germination and seedling growth of sesame seeds exposure to salinity stress.