Iranian Journal of Field Crops Research
Year:2019 | Volume:17 | Issue:1|Papers Count:12

Introduction: Water stress is one of the most important abiotic factors that restrict the growth and production of plants in the world, especially in arid and semi-arid regions. In Iran, a majority of wheat are located in arid and semi-arid regions. In these regions, drought stress occurs due to the lack of water which causes a considerable decrease in the yield of wheat. A suitable strategy to achieve satisfactory production in these areas is to apply deficient irrigation systems with the aim of improving water use efficiency and acceptable yield. Weed competition is another factor which decreases the wheat yield. Wild oat, due to its high compatibility and different ecological conditions, is one of the most important weed in wheat in most areas of Iran. Therefore, it is necessary to understand their behavior in the field, if we plan to apply appropriate weed management methods. Because any management change in the field may change weed behavior, and since the drip irrigation is spreading and the merits of deficit irrigation is known, it is necessary to evaluate their behavior at these conditions. Thus, the aim of this study was to study the wheat response to the interference of wild oat under deficit irrigation conditions. Materials and Methods: An experiment as split plot in randomized complete block design was conducted to evaluate the effects of deficit irrigation in three levels (supply of 100, 80 and 60 percent of crop water requirement as main plot) and wild oat density in four levels (0, 20, 40 and 80 plant m-2) on wheat yield in Shahrood agricultural research center. Wild oat seed was collected from wheat field around Shahrood and was planted with wheat. Crop water requirements calculated by Penman-Monteith equation amended by FAO. Irrigation treatments was applied at the beginning of jointing stage and continued during the growing season. At the end of experiment, two square meters of each plot harvested to measure the grain yield and biological yield. At this time 0. 25 square meters of each plot harvested and yield components were measured. Data were analyzed in SAS software (version 9. 1). Slicing method was used for interaction mean comparison. Results and Discussion: The effects of irrigation regime and wild oat density were significant on the number of spikes, the number of grains at spike, infertile tiller ratio, spike length, plant height, biological yield, grain yield, harvest index and water productivity. Decreasing the water usage to 60% of the water requirement decreased the grain yield and biological yield of wheat by 38. 59 and 11. 64%, respectively at the density of 80 bushes m2. Increasing the wild oat density up to 20 plants per m2 had no significant effect on the grain and biological yield of wheat, while increasing it up to 80 plants in the deficient irrigation regime with 60% of water requirement, decreased the grain and biological yield of wheat to 52. 3 and 26. 2%, respectively, compared with the control (100% of the water requirement) and zero density of wild oat treatment. Spike numbers per unit area showed a significant and positive correlation (r=0. 97**) with yield. Moreover, the results showed that deficient irrigation regime with supplying 80% of the water requirement reduced the grain yield and water usage by 9 and 12%, respectively and it improved the water productivity by 4. 6% compared with the optimum water conditions. Whereas, reducing the amount of irrigation water to 60% of the required water, decreased the water productivity by 13. 6% compared with the optimum water conditions. Conclusions: Results showed that the deficit irrigation decreases the yield and yield components. Reducing water usage to 80% of water requirement reduced the water usage to 12%, consequently, although the water productivity increased, the yield decreased by 9%. Thus, it could be a suitable approach for regions with low water reservoirs. In the other words, in low water regions, the best choice to manage optimum irrigation to achieve constant production and increasing usable water is “ the lower water-the higher productivity” strategy. Increasing wild oat density up to 20 plants m-2 had no significant effect on the grain and biological yield of wheat. However, increasing wild oat density up to 80 plants m2 decreased these properties under all irrigation regimes. The insensitivity of wheat to wild oat competition in lower densities is due to the growth characteristics and competitive ability of Alvand variety.

Introduction: To realize global food demand by 2050 world cereal production should be increased up to 49% compared to 2006. This level of production could be achieved by annual yield increment of 1. 16%. However, the current rates are much lower. At the same time, there is a very restricted area to increase cultivated lands because of resource limitation, provided that increase in crop yields is the main option to sustain food security. Potential yield (YP) could be achieved when limiting and reducing factors are completely absent during crop growth. YP is an indicator for the yielding capacity of a given environment and management system and estimating the difference between YP and actual yield, known as yield gap, is crucial for improvement of crop production systems at regional or national scale. In this study yield gap and its temporal trend for sugar beet, irrigated and rainfed wheat are estimated over Khorasan Razavi province based on the method developed by Global Yield Gap Atlas. Materials and Methods: Following the protocol provided by Global Yield Gap Atlas, Khorasan province was clustered into agroclimatic zones using the proposed indices (cumulative degree days above 0 º C, aridity index and temperature seasonality) based on 10 years (1384-1393) weather data. YP of sugar beet and irrigated wheat for the study period in the climatic regions was first estimated for selected cities within each region using LINTUL model and finally the simulation results were up scaled from cities to region and from regions to the whole province. The model was cross-validated against measured data using leave-one-out (LOO) method to increase accuracy of predictions. Potential yield of rainfed wheat (YW) was estimated from frontier production function which was fitted to yield data over a wide range of annual precipitation. Yield gap (YG) of the studied crops was estimated as the difference between potential (YP) and actual yields (YA) for each region and over the 10-year period. In addition exploitable gap (YG85%=85%YP-YA) was also calculated. Results and Discussion: The accuracy of LINTUL model for simulation of sugar beet and irrigated wheat yields was considerably increased after cross validation and the prediction error was reduced by 6. 5-7. 8%. Mean YP of irrigated wheat in the climatic region 1 (temperate, semi-dry), 2 (hot, dry) and 3 (temperate, dry) was respectively, 7248, 6478 and 7852 and for the whole province 6936 kg ha-1. Time trend of YP for irrigated wheat was not significant in 3 climatic regions however, high annual variation of YP was found over the studied period. Results indicated that up to 74% of this variation was accounted for by changes in the effective grain filling period in response to temperature. YG85% of irrigated wheat in all climatic regions was increased up to 4 t ha-1 during 1384-1388 but decreased later on so that relative gap was 0. 48-0. 50 of YP in 1993. Average YW of rainfed wheat in the climatic regions of the province was estimated as 2000-2800 kg ha-1 with a negative trend due to decreased precipitation, the highest negative slope in YW (59 kg ha-1 y-1) was found in the hot dry region. Rainfed wheat showed an extremely high yield gap in all climatic regions and mean relative yield gap (YG/YW) was estimated as 0. 75-0. 80 over the province. Mean YP of sugar beet in different climatic regions of the province was estimated from 78 to 88 t ha-1 with the lowest potential in hot-dry region. However, declining trend was found in the yield gap of sugar beet in all studied regions with the highest gap filling rate of 1. 44 t ha-1 y-1 in temperate-dry region. Conclusions: Simulated YP of sugar beet and irrigated wheat were higher in temperate-semi arid regions of the province and lower in hot-dry regions. However, cold-semi arid regions had the highest YW of rainfed wheat. When up-scaled over the province, YG85% was about 50% of YP for irrigated wheat and sugar beet and 25% for rainfed wheat. It was concluded that closing yield gap of sugar beet and irrigated wheat would be possible mainly by improving management practices however, for rainfed wheat breeding strategies should be considered as the first priority.

Introduction: Application of chemical fertilizers since green revolution, make the crop production doubled or even tripled in some crops. However, long-term overuse of these fertilizers decreased soil quality. Thus to obtain the same yield, the rate of inorganic fertilizer application steadily increases from year to year. Recent studies revealed that in order to increase the chemical fertilizer efficiency, it needed to integrate organic resources with chemical fertilizers to soil. However, using organic manure in the soil will be decomposed very rapidly. Biochar is a source of high organic carbon which highly resistant to decomposition. It has a porous quality and large surface area which reduces leaching of nutrients. Biochar addition to soils can change microbial biomass, adsorb toxic compounds and improved soil water and pH status. The internal porosity of biochars may help soil microorganisms avoid grazers. Globally demands for plant-based medicines are growing. Black seed (Nigella sativa L. ) is annual plant to Ranunculaceae family, is grown in arid and semi-arid regions of the world. Black seed considered as a spice, medicinal plant and used as seasoning in cooking and foodstuffs. Recently, there has been an increasing interest in integrated approaches in improving crop production to resist conditions of nutrient-poor soil, drought, and salinization. Since, a few attempt has been made to investigate the effects of biochar amendment on medicinal plants in semi-arid agricultural systems, the present study was initiated in agro ecological condition of Mashhad. Materials and Methods: A field experiment was conducted as split plots factorial layout based on a randomized complete block design with three factors and three replications at the Research Station, Faculty of Agriculture, Ferdowsi University of Mashhad, Iran during growing season of 2016. Three levels of irrigation (100, 70, and 40 percent of water irrigation requirement) were assigned as main plots and the combination of three levels of biochar (0, 10, and 20 ton ha-1) and two levels of chemical fertilizers (without and with chemical fertilizer) were allocated as sub plots. Recommended dose for nitrogen, phosphorus, and potassium was 150 kg ha-1, 75 kg ha-1 and 100 kg ha-1, respectively. The size of each experimental unit was 3×2 m2. Black seed thinning was performed after emergence to get a plant population density of 200 plants m-2. Post experimental soil which was amended with biochar and fertilizer were analyzed for total nitrogen, available phosphorus, potassium, soil organic matter, and microbial biomass carbon. Plant criteria which studied were such as grain yield (kg ha-1), straw yield (kg. ha-1) and water use efficiency (base of grain yield). Analysis of Variance (ANOVA) and Duncan multiple range test were used to compare the recoded data. Results and Discussion: Soil N, K, SOM, and Microbial biomass carbon were significantly affected by biochar application. Phosphorus was not affected by biochar. The highest biochar effect on soil characteristics was found under 20 ton ha-1 biochar application treatment. The results showed that application of 10 and 20 ton ha-1 of biochar improved soil nitrogen compared with control treatment. Soil organic matter was increased by 1. 56% compared with 1. 33% in control when 20 ton ha-1 biochar was used. It has been reported that the biochar may increase the organic matter of the poor soils. The soil microbial biomass carbon was increased by biochar and fertilizer application. It seems that the reason for increasing soil microbial biomass by adding biochar to the soil is enhancing available soil nutrients, adsorption of toxic compounds and improved soil water and pH status. The internal porosity of biochars may help soil microorganisms avoid grazers. Combine use of fertilizer and biochar were more affected on plants growth than biochar or fertilizer alone. The interaction between biochar, chemical fertilizer and water requirements significantly affected the seed and straw yield. The significant increase of grain yield, straw yield observed in I2B2F2 (70% water requirement+10 ton ha-1 biochar+ with chemical fertilizer) and I2B3F2 (70% water requirement+20 t. ha-1 biochar+ with chemical fertilizer) treatments. Biochar significantly increased water use efficiency which shows that under water deficiency, biochar can increase the uptake of water and nutrients. As a result, plants tolerance against water deficiency increase and more yields will be produced for a specific value of water. This means the water use efficiency can increase and the use of water will decrease. Conclusions: This study confirmed that biochar application can help in increasing of black seed production through the improving some physical and chemical properties of the soil such as soil pH, soil nutrient availability, soil nutrient holding capacity, and soil microorganism conditions. Although the application of 20 ton ha-1 biochar improved soil properties compared with 10 ton ha-1, the difference was not significant. Application of biochar with chemical fertilizers had better effects on seed and straw yield, compared with solely application of biochar and chemical fertilizers. It may belong to the biochar ability to decrease nitrate and other elements leaching due to its high porosity and high water retention capacity which increased water use efficiency in the plant. This is important in particular, in arid and semi-arid areas, where reduces the amount of water consumed and increases water yields for plants that are under water stress. The seed production of black seed was not affected by reducing water requirements up to 70 % of its total water requirements when biochar was applied. This means that, by using the biochar in soil, only 70% water irrigation required. These results may use for water saving in agriculture in arid and semi-arid conditions.

Introduction: Canola (Brassica napus L. ) is one of the most important oil crops in the world. It has placed in third rank after soybean and palm and has the fastest of growth rate among oil seed in recent decades too. Canola yield was 1592 and 1567 kg. ha-1 in Iran and the world in 2003, respectively, however it has increased to 2125 and 2043 kg. ha-1 in Iran and the world in 2014, respectively. Crop physiologist should investigate the important physiological parameters which in the past have increased yield and can help to increase the quality and quantity of crop yield in the future. Therefore, the current study was carried out to evaluate the physiological traits associated with canola (Brassica napus L. ) genotypes yield improvement. Materials and Methods: Experiment was conducted as randomized complete block design with four replications at Higher Education Complex of Shirvan during growing seasons 2014-2015 and 2015-2016. Treatments were included 20 cultivars and lines of rapeseed. The record of phonological stages was done based on Sylvester-Bradley (1984)’ s method. Before the plants showed elongation. Aboveground biomass and leaf area index (LAI) were measured from destructive sampling and it has been continuing at intervals of 6 to 10 d until physiological maturity. The ratio intercepted photosynthetic active radiation (PAR) was obtained by measuring of radiation at the top and bottom of the canopy with a Ceptometer (ACCUPAR model LP-80). Light was measured just before each destructive sampling between the hours of 12 to 14 on clear days. To calculate the daily cumulative solar active radiation we used RLY-calc program (Soltani, 2011). In order to investigation of growth indices, we have divided the varieties to three group based on cluster analysis and is select a variety as group representative. The groups are included high yield (Bilbao), medium yield (Karaje 3) and low yield (Sarigol). Results and Discussion: Results indicated that there were significant differences among studied varieties in terms of phenological traits. So that Sarigol, Talayee, Shirali, Zafar and Zarfam were achieved earlier than others to physiological maturity. Positive and significant correlation of flowering duration with yield and the number of pod plant-1 has showed its importance in determination of yield. Positive and significant correlation among flowering duration with yield (r=0. 66**) and the number of pod per plant (r=0. 88**) showed its importance in determination of yield. Also, the most important of stage at making yield was affected by environmental conditions such as temperature, radiation and rainfall. LAI for Bilbao was higher than Sarigol and Karaje 3. Also, Sarigol was achieved maximum LAI earlier than two other varieties. There was strong correlation between yield and maximum dry matter accumulation (r=0. 81**). The synchronization of maximum LAI with more solar radiation was much more important to achieve maximum yield. In the first year of experiment, crop growth rate (CGR) and relative growth rate (RGR) were higher than second. There was more solar radiation in first year that it was increased growth indices. The average extinction coefficient of light (KPAR) is estimated 0. 70 and 0. 72 in the first and second year of experiment respectively. In the first year of experiment, KPAR was varied between 0. 65 (Shirali) to 0. 76 (Modena and GKH-2005). In the second year, the highest and lowest extinction coefficient was belonged to the varieties Zafar (0. 80) and Karaje 3 (0. 63) respectively. The average of radiation use efficiency (RUE) is estimated between 3. 8 and 3. 6g MJ. m-2 in the first and second year respectively. Reducing light use efficiency in the second year can be probably because of obvious difference of weather between two years especially decreased of radiation. In other words, more scattered radiation in the second year than first year can be a major reason for this difference. In general, grain yield in the first was more than the second year of the experiment. The average yield of cultivars in the first and second year was 453. 8 g. m-2 and 401. 8 g. m-2 respectively. The highest yield in the first year belonged for Bilbao, Kodiak, SW102, GKH-305 and Traviata with the mean 495. 5 g. m-2 and the lowest yield related to Zarfam, Sarigol, Talaei, Shiraly and Modena with the average amount of 370. 5 g. m-2. The highest yield in the second year belonged to Bilbao, GKH-305, Slm046, L72, SW102, Kodiak and Traviata with the average amount of 450. 3 g. m-2 and the lowest yield belonged to cultivars Talayeh, Opera, Karaj 3, Okapi, Modena, GKH-2005 and Karaj 1 with an average yield of 349. 7 g. m-2. In general, cultivars with a higher LAI, as well as whose their maximum LAI coincided with higher radiation input had higher yield. Conclusions: It can be concluded the importance of the synchronization maximum leaf area index with more solar radiation. For canola if the maximum LAI is less than four can say that growth and yield will be limited due to lack of leaf area because LAI about four is sufficient to obtain about 90 % of solar radiation. Therefore in spite of second year, in the first year LAI was not limiting factor to achieve maximum biomass. Since maximum LAI of canola occurs in flowering stage, so higher leaf area index at this time was caused the cultivars use more solar radiation. In addition to maximum LAI, the coincidence maximum LAI with higher radiation input was important factor to achieve a higher yield as a result more dry matter accumulation.

Introduction: Chickpea is the most important field crop among food legumes in Iran. According to the published statistic by agricultural ministry of Iran, cultivation area of chickpea varies between 550– 900 thousand hectares that more than of 90% them cultivated under dryland condition. More than 63% of country has cold and higher cold climates and more than 60% of drylands in Iran located in cold and highlands where temperature declines to-25° C in some years, with continues cold duration (more than 100 days per year). Reports show that the yield of chickpea is low in cold areas (about 500 kg. ha-1) because of the spring planting and lack cold tolerant cultivars suitable for autumn planting. In cold regions that absolute minimum temperature in winter reaches under-6° C till-12° C, studies showed that it may be complete damage occurrence if chickpea planted in autumn. Studies showed that planting of cold tolerance varieties increased the yield of chickpea almost twice. Hence, screening chickpea germplasms for cold tolerance will help to release new cold tolerant cultivars. The literature review suggests that most studies related to the evaluation and screening of chickpea cold tolerance were done under natural conditions (field), but the spatial and temporal variation in the weather under such circumstances may lead to different results. Researchers reported that using from controlled condition for screening cold tolerance genotypes in chickpea germplasm would prevent seasonal restrictions, saving time and increasing the accuracy of studies while eliminating unwanted factors. Materials and Methods: In order to study on cold tolerance of 33 Kabuli chickpea genotypes along with three controls (Saral, ILC 533 and Jam), this study carried out in square lattice design (6×6) with two replications under controlled condition (cold room) at Maragheh Dryland Agricultural Research Station, during growing season 2014-2015. Ten seeds of each genotype after surface sterilized with fungicide (Benomile with 0. 015%) planted in five cm depth in planting boxes (100×80×25 cm) at early autumn (29 September). In order to simulation of natural growth condition in autumn and acclimation of seedlings, planted boxes incubated outside of green house. Number of germinated seeds was recorded and seedling of genotypes at six-week stage, incubated in cold room. The temperature of cold room decreased two degrees in each hour up to minus 15° C and seedlings remained for one hour at this temperature. A thin layer of ice nucleation active bacteria sprayed on the surface of seedlings at-2° C in order to establish ice nucleation and prevent ultra-freezing of seedlings. Then temperature increased up to 4° C for three days and boxes transferred to green house for two weeks under 20± 3° C. Frost resistance ratios (FRR) of genotypes calculated and analyzed. According to other studies and reports the genotypes with 0. 91-1 and 0. 81-0. 90 FRR classified in highly resistance and resistance groups, respectively. Results and Discussion: Results showed that there was significant (p ≤ 0. 01) differences in frost resistance ratio (FRR) among the investigated genotypes. Lines 14 (Flip98-138C* SEL99TER85074)*Sel. 99th. 15039, 28 (FLIP 00-84 C) and Saral cultivar had the highest FRR (100, 98 and 89 survived percentage, respectively) among the genotypes. Also Kaka cultivar and line 12 (Flip 98-28C*Flip 98-22C)* ICCV2 had the lowest frost tolerance among the studied genotypes. About 30% of genotypes could tolerate the frost damage, for example, genotypes 14 and 28 had between 0. 9-1. 0 ratio, whereas, the FRR of susceptible check (ILC533) was 0. 13. Conclusions: The existence of wide range of diversity for frost resistance among the studied germplasm would be useful to introduce new tolerant chickpea cultivars with autumn-sown potential. Moreover, the tolerance of Saral cultivar to frost stress, its cultivation under cold dryland regions could be recommended as the first frost tolerant variety in the country.

Introduction: Current estimates indicate that 25% of the world agricultural lands are affected by water stress. Iran, with an annual 228 mm of rainfall, is classified as a dry region in the word. Wheat is one of the main cereal crops, cultivated for human feeding. In order to increase crop yield per unit area, largely chemical fertilizers are used. The result of these activities in recent years has been the crisis of environmental pollution, especially water and soil pollution that threatens human society. Phosphorus is one of the limiting elements for crop production. It is essential for energy transfer, photosynthesis and other biochemical and genetic activities of plant. Biofertilizers have been used as source to improve plant nutrients in sustainable agriculture. Phosphorus Solubilizing Bacteria (PSB) plays an important role in phosphorus nutrition by enhancing its availability to plants through release from inorganic and organic soils phosphorus pools by solubilizing and mineralization. Mycorrhizal crops often have greater tolerance to drought than nonmycorrhizal crops. The use of arbuscular mycorrhizal fungi capable of forming symbiotic associations with most agricultural crops and has potential under such systems due to its higher binding capabilities and mineral nutrition. Therefore, the main of this study was to study the effect of phosphate solubilizing bacteria and mycorrhizal fungi on root characteristics and grain yield in dryland wheat cultivars. Materials and Methods: This experiment was carried out as factorial arrangement based on a randomized complete block design with three replications at the Agricultural Research Station of Ilam University (46*28' N, 33*37 E; elevation 1174 m) and Sarableh Agricultural Research, Recources Center (34*46 N, 33*45 E; elevation 975 m) during growing season 2013-2014. Experiment factors consisted of two dry land cultivars (Keras Sablan and Saji) and fertilizer sources including of 1: without application of phosphorious chemical fertilizer, 2: 50 kg. ha-1 phosphorous chemical fertilizer, 3: pseudomonas putida (PSB), 4: Glomus mosseae (GM), 5: PSB+GM, 6: PSB+GM+25 kg. ha-1phosphorous chemical fertilizer, 7: PSB+ 25 kg. ha-1 phosphorous chemical fertilizer and 8: GM+25 kg. ha-1phosphorous chemical fertilizer. At flowering stage root traits such as root volume, root area, root diameter, root length density and root surface area density were studied and measured. At full maturity, agronomic traits such as spikes. m-2, grains. spike-1, 1000-grain weight, grain yield and biomass yield were recorded using a sample of ten random guarded plants from the middle ridges of each plot. The data were analyzed statistically by SAS program and the data means were compared by Duncan's multiple range test (DMRT). Results and Discussion: Results indicated that interaction effect between cultivar× fertilizer sources had significant effect on root length total, root volume, root area, root diameter, root length density, root surface area density, spike. m-2, grains. spike-1, 1000-grain weight, grain yield and biomass yield. Using fertilizer sources had positive and significant effect on root traits and grain yield in two dryland wheat under dry land condition, so that Saji cultivar ×GM+25 kg. ha-1 had the highest root volume (4. 6 cm3), root area (70. 9 cm-2), root length density (0. 158 cm root length. cm-3 soil), root surface area density (84. 3 cm2. cm-3), spike. m-2 (257. 5 spikes), grains. spike-1 (42. 7 grains), 1000-grain weight (39. 7 g), grain yield (3571. 6 kg. ha-1) and biomass yield (7840. 6 kg. ha-1) and the lowest root traits and grain yield belonged to Keras Sabalan×check treatment. There was significant different between cultivars to response of Using of phosphate solubilizing bacteria and mycorrhizal fungi, so that Saji cultivars had the best response to mycorrhizal fungi. Therefore with regard to cultivation of wheat is facing to drought and heat stress indicated that Saji cultivar and using of mycorrhizal fungi can be the best result under dry land conditions. Conclusions: The results indicated phosphate solubilizing bacteria (PSB) and mycorrhizal fungi (GM) had positive effect on root system and grain yield, so that root traits and grain yield had the better status in presence of inoculation with GM. In fact PSB and GM could alleviate the partial of grain yield in presence of dry land farming. Recent studies indicated that symbiosis bio-fertilizers also improved soil physical and chemical traits and increaced organic matters content, root system and P available to coexistent plant.

Introduction: Sesame (Sesamum indicum L. ) is considered as the queen of oilseeds for its high oil quality. Sesame oil is rich in micronutrients, antioxidants and essential amino acids as well as polyunsaturated fatty acids. Proper understanding of the relationship between grain yield and its components can significantly improve the performance of the breeding program through the proper use of selection indicators. Materials and Methods: In order to determine the relationship between the seed yield and oil percentage with some important agronomic traits, and to find the direct and indirect effects of important agronomic traits on both seed yield and oil percentage and also select best genotypes in terms of different traits, 91 sesame genotypes (received from botanical gene banks of Germany, Canada and Australia) were studied based on an augmented design with 3 checks (Oltan, Yellow white, Naz tak shakheh) at seed and plant improvement institute, Karaj, Iran in 2016. 17 agronomic traits including flowering date, maturity date, first capsule height from surface of earth, height of plant, number of branches, number of capsule per branches, number of capsule per main stem, number of total capsule per plant, seed number per capsule, seed weight per capsule, 100-seed weight, capsule weight, capsule diameter, capsule length, oil percentage, biological yield and seed yield were studied. Results and Discussion: The results of simple correlation indicated that seed yield per plant had a high correlation with total number of capsules per plant, number of capsules in branches, biological yield, number of capsules per main stem and plant height. Also 100 seed weight, seed yield per plant, number of capsules per main stem, number of capsules per plant and seeds weight per capsules were in a high correlation with oil percentage. The result of path analysis showed that the number of capsules per plant, number of capsules per branch, biological yield and capsule length exerted the greatest positive effects on seed yield and therefore suggest that they can used as selection criteria in seed yield improvement. Also seeds weight per capsule, capsule length, seed yield and number of capsules per main stem exerted the greatest positive effects on oil percentage. The results of principal component analysis showed that 6 components comprised 82. 77 % of the total variations in genotypes. In the first components of this study biological yield, seed yield, capsule weight, number of capsules in the branches and number of capsules per plant had high positive coefficients. The number of seeds per capsule, the seed weight of a capsule and the weight of a capsule had the highest coefficients in the second component. In the third component, the traits of the day to the beginning of flowering and the day to the beginning of the maturity had the highest positive coefficients and the height of the plant had a high negative coefficient. In the fourth component, the weight of 100 seeds, oil percent and seed weight per capsule had the highest positive coefficients and the height of the first capsule from the ground surface had the highest negative coefficient. The fifth component, including oil percent, capsule length and height of the first capsule from the ground had positive coefficients and the numbers of capsules in the main branch were negative. Finally, the sixth component included the number of seeds per capsule and the number of capsules in the main branch with positive and 100-seed weight and the height of the first capsule from the surface with negative coefficients. Lao hong zhi ma and Black c-2-c, Dulce 101/87 and Bukbak had the highest yield in component 1 and 2 biplot. The genotype number 79, with the name of White c323-2, had a good relative yield and also a good relative seed oil content. In addition, genotypes number 79 and 51, with the names of White c323-2 and Local 123, have a good relative yield and also relatively early. Finally, genotype number 49, with the name of Lao hong zhi ma, had the highest relative yield and seed number per capsule. Conclusions: For improvement of each component, we must pay attention to the related traits because gene or genes which control number of capsules per plant, probability control biological yield, capsule weight and other significant traits in this component too, and the component or gene which control this traits is similar gene or factor. By identifying these phenological and morphological patterns that effective in the structure of sesame and determining the relationships between them, breeders can use them in future programs.

Introduction: Wheat is important plant in the economy of the world. Between wheat cultivars, bread wheat (Triticum aestivum L. ) is the best cultivar for nutrition. Drought stress led to decrease production, therefore, it causes problems for nutrition and agriculture. Iran is located in dry belt of the earth and its annual rain average is 250 mm. In dry land, grain filling phase is faced with a warm season when the air temperature is high and soil water storage is reduced. For screen best drought tolerant genotypes must use from drought tolerance and susceptibility indices. The purpose of this research was to identify and determine drought tolerant and high yield lines for introduction in drought stress conditions during reproductive phase and to determine the indices with a desirable efficiency for evaluating reaction of genotypes to stress conditions. Materials and Methods: An experiment based on randomized complete bock design with three replications was conducted Torogh Mashhad Agricultural Research Stations, Iran, during 2014-2016 growing seasons. In this research eight genotypes of winter wheat with three control cultivars of Mihan, Orum, zare were compared under two conditions of full irrigation and water stress during reproductive phase. Statistical analysis was performed by using SAS and SPSS software. After harvesting, yield and indices drought tolerance indices including SSI (Stress Susceptibility Index), STI (Stress Tolerance Index), GMP (Geometric Mean Productivity), HARM (Harmonic Index), MP (Mean Productivity), YSI (Yield Stability Index), YI (Yield Index), DI (Drought Index), MSTI (Modified Stress Tolerance Index), ATI (Abiotic Tolerance Index), SSPI (Stress Susceptibility Percentage Index), RE% (Reduction Percentage), SNPI (Stress non-Stress Production Index), TOL (Tolerance). Results and Discussion: Results showed that the effect of year, genotype and irrigation and interaction effect between year and genotype were significant on all of studied traits. Drought stress decreased yield of genotypes about 32% and 30% in the first and second year, respectively. Other investigation showed that drought stress at the reproductive phase led to reduce current photosynthesis and high respiration. According to Fernandez, indices that have a significant correlation with grain yield in both stress and non-stress conditions are superior indices because they are able to distinguish high-yield genotypes in both conditions. In our research there was a significant and positive correlation between GMP, MSTI, HM, STI, MP with grain yield in both non-stress and stress conditions. In drought stress conditions genotype 8 and 9 ranked had the highest yield (5176 and 5079 kg ha-1), and were selected as the most tolerant genotype. Conclusions: This research showed that drought stress at the reproductive phase reduced grain yield. GMP, MSTI, HM, STI and MP showed significant and positive correlation with grain yield in both non-stress and stress conditions. Genotype 8 had the highest rank in all of the mentioned indices, it could be considered as tolerant genotype to the drought stress at the reproductive phase due to the proper grain yield in both stress and non-stress conditions.

Introduction: Intercropping is defined as the growing of two or more crops at the same time in the same piece of land. Intercropping of legume with non-legume compared with monoculture has many advantages such as reducing the risk of crop failure, making efficient use of available land, improving productivity and income, more efficient use of resources (water, nitrogen, and radiation) and increasing food security in vulnerable production systems. Biofertilizers are important not only for the reduction of quality of chemical fertilizers but also for getting better yield in sustainable agriculture. Application of biofertilizers and no use of chemical fertilizers are rapidly gaining favor. Arbuscular mycorrhizal fungi (AMF) has been well documented to be a bio-fertilizers that have a symbiotic relationship with many crops and by increasing the uptake of nutrients mainly phosphorus, and enhancing the water absorption and resistance to pathogens, improves growth and yield of host plants in sustainable agricultural systems. The main objective of the present study was to determine the effect of biofertilizers (nitrogen, phosphorus, potassium and sulfur solubilizing bacteria+ Arbuscular mycorrhizal fungi) and intercropping on seed yield and yield components of linseed and faba bean. Materials and Methods: This experiment was conducted as factorial layout based on randomized complete block design with three replications at the Research Farm of the Faculty of Agriculture, Urmia University, Iran, during growing season of 2017. The first factor was five intercropping patterns including 1 row linseed + 1 row faba bean, 2 row linseed + 2 row faba bean, 3 row linseed + 3 row faba bean, and monocropping of each crop and the second factor was included control (no fertilizer), and biofertilizers (nitrogen, phosphorus, potassium and sulfur supplier bacteria+ arbuscular mycorrhiza fungi). Before the sowing, the related biofertilizers were shaked completely to cover the whole seeds surface after which the seeds were shadow-dried and planted, irrigation was done immediately after seed sowing. No fertilizer was used during the growing season. In addition, the land equivalent ratio (LER) was calculated to determine the advantages of intercropping. The Analysis of variance was performed using SAS 9. 4 software; means were compared by using Duncan's multiple test at 0. 05 probability level. Results and Discussion: The results showed that the effect of cropping pattern on all measured traits was significant on height, number of lateral branch, number of capsule per plant, number of seed per capsule, 1000-seed weight, biological yield, seed yield, oil percentage of linseed and on height, number of lateral branch, number of pod per plant, number of seed per pod, 1000-seed weight, biological yield, seed yield of faba bean. The highest seed yield of faba bean (4. 280 t ha-1) and linseed (2. 230 t ha-1) were obtained in monocropping treatments, respectively. The higher production in linseed and faba bean monocropping may be due to the less disturbance in the habitat in homogeneous environment under monocropping systems. The results showed that biofertilizer had a significant effect on all traits, in linseed and faba bean. The highest yield and yield componenet of both plants were achieved in use of biofertilizers. In linseed, the highest oil percentage of all treatments was higher than solecropping. Also, total LER was more than 1 and the highest values were observed in all treatments. The maximum LER values (1. 50) were obtained for intercropping 2 row of linseed + 2 row of fababean with using biofertilizers. It seems that better utilize of the growth resource in the intercropping led to reach this result. Conclusions: In general, the results of this experiment showed that the faba bean and linseed yield were influenced by different intercropping patterns and biofertilizer. The highest seed yield for both plants (faba bean and linseed) were achieved in monocropping. In the present study, application of biofertilizers could improve the yield and some characteristics of faba bean and linseed. In addition, with application of biofertilizer the seed yield of linseed and faba bean about 38% and 31% compared with control (non-consumption), respectively. It seems that the use of biofertilizers in intercropping is one of the suitable strategies for achieving optimal yields with minimum inputs, which in the long run can reduce the need of crop systems to chemical inputs.

Introduction: According to the present state of climate science, the increase in greenhouse gas concentrations will result in changes of the climate parameters; particularly, an increase of the global temperature and changes in precipitation are expected. These changes in climate, which are likely to occur during future decades, may have significant consequences (positive or negative) on the development, growth, and crops yield. Climate change and its impacts on water recourses is known as one of the most important challenges which human would be faced with it in future century. Future climate change in each region can be predicted through the models of the Globa Circulation Model (GCM). It is also possible to investigate the effect of climate change on the yield and the water requirement of plants using performance predictive models as Aquacrop model. The main objective of this study is to assess the effect of climate change on the future climate of Moghan plain and also, simulation three corn hybrids parameters such as grain yield, biomass yield and growth period of corn, under different irrigation treatments. Materials and Methods: In this study, AquaCrop model was used to simulate grain yield and biomass of different maize hybrids under the future climate in different irrigation treatments. For this purpose, rainfall data, minimum temperature, maximum temperature and sunshine model of the LARS-WG fine-scale model with using six general circulation models (ADCM3, HadCM3, IPCM4, GFCM2, NCCCSM INCM3), for which three scenarios the fourth report of the Climate Change Board (A1B, A2, and B1) was predicted and reviewed for the Moghan region during 1970-2010, 2011-2030 and 2046-2065. AquaCrop model was calibrated and validated by field data (2015 and 2016 year), corn plants collected in the area. Then, the grain and biomass yield values in the upcoming periods for different irrigation treatments (I1 = normal irrigation, I2 = irrigation cut off at vegetative growth stage, I3 = irrigation cut during flowering stage and I4 = irrigation cut off at the seed filling stage) different maize hybrids (C1 = SC704, C2 = SC703 and C3 = SC705). Results and Discussion: According to the results, in the statistical period of 2011-2030 compared base periods (1970-1999), the average monthly temperature was 1. 41, 1. 35, and 1. 66 ° C, respectively for scenarios A1B, A2, and B1. Also, the average monthly rainfall will be reduced to of 6, 11 and 15 mm, respectively, for scenarios A1B, A2 and B1, and during 2046-2065 periods, compared to period of 1979-2010. Furthermore, the monthly average of the temperature will be increased to 2. 9, 2. 69 and 2. 32 ° C respectively, for scenarios A1B, A2 and B1. During this period, the amount of rain reduction was estimated at 18, 15 and 14 millimeters, respectively, in scenarios A1B, A2, and B1. The results of simulation of grain yield and total biomass of maize cultivars under the influence of irrigation administrations using AquaCrop model showed that the root mean square variables of seed and dry matter yield errors in years 2015 and 2016 were 413 and 891 kg. ha-1. The root mean square mean of normalized error of seed and dry matter yield was 11 and 10%, respectively. Also, with using future meteorological data under different scenarios was observed that growth period, grain yield and biomass yield during 2011-2030 and 2046-2065 periods for three scenarios A2, B1 A1B were decreased. Among the cultivars studied, Hybrid SC704 corn had more growth and yield than other corn hybrids, and this figure could be recommended for future climate change for Moghan area. Conclusions: Future meteorological data under different scenarios of climate change will decrease growth period, grain yield and biomass yield during 2011-2030 for scenarios A1B, A2 and B1, respectively, 7 %, 16 % and 9%, and during period 2045-2065 for scenarios A1B, A2 and B1, respectively, 13 %, 14 % and 12 percent. Among the cultivars studied, the growth period of SC 704 hybrid was higher for all three scenarios than other hybrids and it has more growth and yield, therefore can recommended to change future climate for Moghan region.

Introduction: Drought stress has osmotic and physiological effects on plants, resulting in reduced growth, metabolic disorders and oxidative stress in plants. Different plants use several strategies to cope with drought stress. External application of different compounds such as organic solvents and minerals is a solution to increase drought tolerance in plants. Salicylic acid is recognized as a plant hormone and its role in defense mechanisms against biological and non-biological stressors is well defined. The purpose of this experiment was to evaluate the effect of salicylic acid on reducing the effects of drought stress on yield, water use efficiency and some physiological characteristics of the barely. Materials and Methods: This experiment was carried out as factorial experiment based on randomized complete block design with three replications in the Kizor fields located in the city of Sabzevar in 2017. The altitude of this area is 1195 m above sea level and is 36° 5 N latitude and 44° 3' E longitude. The treatments included irrigation at two levels of cut-off irrigation (irrigation cut from booting to harvesting stage) (Z39) and non-cut-off irrigation and salicylic acid spraying treatment at four levels of zero (control), two, four and six mM at stage of shoots on barley. Data were analyzed with the SAS software ver 9. 1 and the means were compared with LSD test. Results and Discussion: The results showed that in both conditions of non-cut-off irrigation and cut-off irrigation, the highest number of spikes, number of seeds, seed yield and biological yield per m2 were obtained in two to six mM of salicylic acid, respectively, and the lowest was related to control treatment. The lowest water use efficiency (0. 38) was obtained under non-cut-off irrigation conditions without salicylic acid and with the consumption of salicylic acid up to six mM, water use efficiency increased. Also, salicylic acid spraying in cut-off irrigation conditions compared to non-cut-off irrigation led to increase water use efficiency. In both conditions, non-cut-off irrigation and cut-off irrigation, the highest and lowest grain yields were obtained from 6 mM salicylic acid and control treatments (without salicylic acid spraying), respectively. Under non-cut-off irrigation and cut-off irrigation, spraying with 6 mM of salicylic acid increased the grain yield by 44% and 48% compared to control (without salicylic acid spraying). It seems that the effect of salicylic acid spraying in cut-off irrigation conditions was more effective than non-cut-off irrigation conditions. The cause of higher water use efficiency in cut-off irrigation conditions in comparison with non-cut-off irrigation was high waste of water due to evapotranspiration and deep penetration in non-cut-off irrigation treatments. Spraying with salicylic acid by stimulating the growth of hair and sub-roots plays an effective role in increasing water use efficiency. In cut-off irrigation conditions, salicylic acid consumption has reduced the amount of electrolyte leakage so that the spray at a concentration of 6 mM of salicylic acid compared to the control (without salicylic acid spraying) decreased electrolyte leakage about 38 %. The reduction of membrane damage due to the use of salicylic acid is related to the production of antioxidants. Spraying with salicylic acid increases the stability of the membrane against oxidative stresses. Conclusions: Water deficit at first affecting the structure of the cell membrane, increased the permeability of the membrane relative to the ions and macromolecules and at second stage decreased the photosynthesis by decreasing the chlorophyll index, which finally reduced the yield and its components. Also, salicylic acid alleviate drought stress by reducing ion leakage, increasing proline concentration and chlorophyll index resulting to improved wheat grain yield under cut-off irrigation conditions compared to non-cut-off irrigation.

Introduction: Wheat production is an important component for national food security. Studying the impact of future climate change on crop production is crucial to manage crop productivity. Improving our understanding of potential responses of the wheat plant to these changes while taking into consideration agricultural management is required for identifying best adaptation strategies. In Khorasan Razavi province, over 12% of the total cultivated wheat area is belong to Torbat-e Jam region. The current study aimed to quantify the potential impacts of climate change on irrigated wheat yield in the next 30 years for this region. Materials and Methods: In this study, information on regional cropping systems and meteorological data to study the effects of climate change were collected and finally, the impact of climate change on irrigated wheat yield was studied using simulation approaches under different climatic scenarios. Long-term daily weather data for future was generated using MarkSim weather generator software and the past meteorological data was gathered from regional weather station. Daily weather data generated by four scenarios RCP2. 6, RCP4. 5, RCP6, and RCP8. 5 for a 30-year period. The generated and measured daily weather data was used for running CERES-Wheat model. Finally, crop model outputs were used to interpret climate change impacts on wheat growth and production. Results and Discussion: The average air temperature during the wheat growth period showed that temperature increased about 1. 6% in the last five years compared to the first five years of the baseline 30-years period. Furthermore, the average annual precipitation for the last 5 years was 51 mm less than the first 5 years of the baseline period. The air temperature will increase about 1. 1, 1. 6, 1. 2 and 1. 8 ° C during the wheat growth period for the near future (30 years) under the RCP2. 6, RCP4. 5, RCP6, and RCP8. 5 scenarios, respectively. The precipitation over the wheat growth period will reduce by 9 and 8% under RCP4. 5 and RCP8. 5 scenarios, respectively. Furthermore, the precipitation over the growth period would increase by 11 and 17% under RCP2. 6 and RCP6 scenarios, respectively. The simulated wheat yield by the CEREC-Wheat model showed that the grain yield increased by 5% in the first 5 years compared to the last 5 years of the baseline period (1998-2017). The biomass production and harvest index (HI) also increased by 2. 3 and 1%, respectively. The increased dry matter production and HI can be due to temperature increase during the cold seasons, and more amount of precipitation during the reproductive growth. The simulated wheat growth during the near future period (2018-2047) showed that wheat growth cycle will reduce from 5 to 7 days under different emission scenarios. In the different soil textures, wheat yield under RCP2. 6, RCP4. 5, RCP6, and RCP8. 5 scenarios will increase by 24. 4, 19. 9, 24. 9 and 25. 2%, respectively. Furthermore, the highest and the lowest yield were obtained from clay and sandy clay loam soils, respectively. Under the different emission scenarios, the mean incident light and light use efficiency during the growth period would be increased by 20. 8-24. 6% and 5. 5-8. 3%, respectively, in projected climate change as compare to baseline period. Reducing irrigation water as amount of 300 m3 ha-1 and simultaneous increase in irrigation water use efficiency are possible incident scenarios for the near future. Based on these scenarios, simulations showed that grain yield increased 26. 3, 19. 6, 27. 2 and 25. 6 % under RCP2. 6, RCP4. 5, RCP6, and RCP8. 5 emission scenarios, respectively. Conclusions: The increased temperature and atmospheric CO2 concentration during the next 30 years will decrease wheat growth cycle, but increase the potential biomass and grain wheat yield under the different emission scenarios. The results showed that the increased yield production will occur under climate change conditions, even if the available irrigation water would decrease by 300 m3 ha-1.