فهرست مطالب محسن موحدی دهنوی

Excessive reliance on the use of chemical fertilizers to produce agricultural products today has led to major environmental problems. Therefore, in order to reduce the soil pollution and the cost of producing chemical fertilizers, it is necessary to use bio-fertilizers. This research was done to aim of determining the appropriate amount of phosphorus chemical fertilizer in combination with bio-fertilizers for soybean. The experiment was conducted as a factorial base of a randomized complete block design with 3 replications. The first factor included the application of phosphorus chemical fertilizer (zero, 60, 120 and 180 kg/ha triple superphosphate) and the second factor included the application of phosphorus bio-fertilizer (control, Behroshd bio-fertilizer, mycorrhiza and Behroshd bio-fertilizer + mycorrhiza) The increase of phosphorus chemical fertilizer from zero to 180 kg/ha increased chlorophyll index (17%), plant height (8.5%) percentage of absorbed light (1.6%), biological yield (24%) and yield components of soybean significantly. The use of biological fertilizers also caused a significant increase in the mentioned traits. The interaction effect of chemical and biological phosphorus fertilizers was significant on the leaf area index and soybean yield, so that at each level of chemical fertilizer use, the highest of these traits was related to the application of Behroshd bio-fertilizer + mycorrhizal. Increasing of phosphorus chemical fertilizer, reduce the bio-fertilizers application efficiency in soybeans yield improving. Therefore, in order to achieve sustainable soybean production, the combination of biological fertilizers and lower amounts of chemical fertilizers should be used.

St. John's wort (Hypericum perforatum L.) is a medicinal plant that is more than 2000 years old. Drought stress is one of the most limiting environmental factors in the growth and production of plants. Plant symbiosis with mycorrhiza fungi and foliar spraying of essential elements can be one of the most effective solutions to deal with drought stress. This research also aims to evaluate the effect of mycorrhizal fungus and zinc sulfate foliar spraying on some biochemical traits and economic yield in St. John's wort under different irrigation regimes in a split factorial experiment with a basic randomized complete block design in three repetitions carried out during the three cropping years of 2018, 2019 and 2020. The main factor is irrigation regimes at three levels (100, 75 and 50% of irrigation needs); sub-factors were ZnSO4 foliar spraying at three levels (0, 3 and 6 per thousand) and inoculation with an AMF (Funneliformis mosseae) at two levels (inoculated and uninoculated). The results showed that the triple interaction of irrigation regimes + foliar spraying + mycorrhiza in all three years had a significant effect on chlorophyll content, proline, soluble sugars, malondialdehyde and economic yield. Increasing irrigation stress had a reducing effect on chlorophyll content, economic yield, and the relative water content of leaves, but on proline, soluble sugars and malondialdehyde had an increasing effect. At each stress level, the highest economic yield was obtained in the treatment of 6 per thousand foliar spraying + inoculation with mycorrhizal fungi. Generally, foliar spraying of zinc sulfate + mycorrhiza increased the content of chlorophyll, sugar solvents and the relative water content of the leaf, caused the adjustment of the stress conditions and increased the resistance of the plant against drought, and by improving the quantitative and qualitative biochemical traits, it increased the economic yield of the St. John's wort plant.

Legumes are considered the second source of human food after cereals and have significant nutritional and agricultural values. Because of the drought resistance of lentils cultivars, dryland production of spring types could be important in the suitable regions with the proper temperature and rainfall, such as temperate regions of Yasouj county, Iran. To achieve the optimum yield of lentil using the most suitable cultivar (s) in the most proper sowing date is substantial. Mehraban (2018) reported that the highest grain yield in rainfed conditions belonged to Bilehsawar variety, which may be due to the higher weight of 1000 seeds in this variety. Also, in this research, it was found that the delay in planting by reducing the growth period and drought and heat stress in the seed filling stage causes a decrease in vegetative growth (a decrease in the branches in the plants and also a decrease in biological yield) and also a decrease in yield components such as the number of seeds. To mitigate end season drought stress in dryland lentil cultivation mycorrhizae symbiosis can be a proper practice. In a study by Piade Koohsar (2017), it was reported that the effect of mycorrhizal inoculation on grain yield in lentil plant was significant. He also reported that the highest seed yield from inoculation with mycorrhizal fungus in the Kimia variety was 1939 kg.ha-1, and the lowest seed yield was observed in the control treatment (no inoculation) in the Kalpoosh native stand at 1339 kg.ha-1. The objective of this experiment was to evaluate the effect of sowing date and mycorrhiza symbiosys on physiological and yield traits of lentil cultivars in dry land conditions in Dashtroom, Yasouj, I.R.Iran.
 
Materials and Methods 
This research was carried out in 2020-2021 cropping season in the Deshtrum region, located 10 kilometers from the center of Boyar Ahmad county of Kohgiluyeh and Boyar Ahmad provinces, with average rainfall of 726 mm. The experiment performed as a split factorial based on a randomized complete block design with 3 replications. The main factor was three planting dates (January 28, February 12, and February 27) and the sub-factor was interaction of two factors including three lentil varieties (Sena, Bilehsawar, and Local accession) and mycorrhiza (Funneliformis moseae) (with and without). Leaf proline, chlorophyll, and soluble sugars content, as well as, seed nitrogen and phosphorus were measured. Plant height, grain and biological yield were measured. The data were analyzed using SAS software after performing the normality test and mean comparisons were made using the LSD test, and in the case of interaction being significant slicing was done and means compared by L.S.Means procedure.
 

The results showed significant effect of the triple interaction of sowing date, mycorrhiza, and cultivar on grain nitrogen percentage, total chlorophyll, leaf soluble sugars content, and biological yield. Also, the results showed that the interaction of cultivar and mycorrhiza on the plant height, grain phosphorus, total chlorophyll, the content of leaf soluble sugars, and biological yield were significant. The interaction of sowing date and variety for all studied traits except plant height were significant. Under the January 28 sowing date and mycorrhiza application, Sanna variety obtained the highest percentage of grain nitrogen (4.59%), total chlorophyll content (0.45 mg.g-1 leaf fresh weight), leaf soluble sugar content (about 120 mg.g-1 leaf fresh weight) and biological yield (3243.23 kg.ha-1) in. Also, the highest seed phosphorus percentage (1.67%), leaf proline content (13.16 µmol.g-1 leaf fresh weight), and seed yield (1152.90 kg.ha-1) related to the planting date of January 28 and Sanna variety. Application of mycorrhiza in nearly all of the traits had better performance compared with non mycorrhiza application. We saw that all cultivars had the best nutrient absorption, physiological characteristics and yield under mycorrhizal inoculation.
 

The use of mycorrhizal fungi increased all the measured traits. Also, in all three sowing dates, the variety Sanna had the highest performance in terms of the studied traits. However, the grain yield and biological yield of the January 28 sowing date were higher than other sowing dates; therefore, it can be said that the early planting (28 January) of lentil cultivars in the Dashtrum region helps the plant to achieve the maximum benefit from the growing season. On the other hand, the best result was obtained from the use of mycorrhizal fungi. According to the above conditions, the variety of Sanna along with the use of mycorrhizal fungi is the best variety for early planting in dryland conditions in the Dashtrom region.

The experiment was performed to investigate the effect of different sources of nitrogen fertilizer on yield and yield components of linseed Norman variety.

The experiment was conducted in the form of a randomized complete block design with 13 treatments in 3 replications in April 2012 in farm of Yasouj university. Experimental treatments during : T1-control (without fertilizer application), T2- application of 90 kg.ha-1 urea, T3- application of 10 tons.ha-1 of vermicompost, T4- application of 5 tons.ha-1 of vermicompost, T5- application of Barvar1 biofertilizer (containing sAzotobacter (100 g.ha-1) T6- application of biofertilizer nanoparticles of zinc, copper, iron and nitrogen-fixing bacteria (1 kg.ha-1), T7- application of 45 kg.ha-1 urea + 5 tons.ha-1 of vermicompost, T8- application of 45 kg.ha-1 of urea + Barvar1 biofertilizer, T9- application of 45 kg.ha-1 of urea + nano biofertilizer, T10- application of 5 tons.ha-1 of vermicompost + nano biofertilizer, T11- application of 5 tons.ha-1 of vermicompost + Barvar1 biofertilizer, T12- application of 45 kg.ha-1 of urea + 5 tons.ha-1 of vermicompost + biofertilizer Barvar1, T13- application of 45 kg.ha-1 of urea + 5 Tons.ha-1 of vermicompost + nano biofertilizer.

The results showed that different fertilizer treatments caused a significant increase in morphological traits, yield and yield components, biological yield, oil yield and protein percentage of linseed compared to the control.

Seedling germination and establishment are one of the most sensitive stages of plant life that play a role in plant production, proper plant establishment, plant density, and uniformity and management goals. Osmotic stress has a significant effect on germination percentage and rate. Salicornia persica is an annual halophyte plant that can grow in saline environments. According to the studies and the importance of determining the tolerances of salinity and drought tolerance in germination and plant establishment, this study aimed to investigate the effect of osmotic potentials of polyethylene glycol and sodium chloride on germination and fit of time-moisture and time-salinity models of Salicornia seeds.

In order to investigate the effect of osmotic potentials caused by polyethylene glycol and sodium chloride on germination and fit of Hydrotime and Halotime models of Salicornia seeds, two experiments were conducted based on a completely randomized design at Yasouj University in 2020. The first experimental in drought stress treatments included 13 levels of osmotic potential (zero, -0.3, -0.6, -0.9, -1.2, -1.5, -1.8, -21, -2.4, -2.7, -3, 3.3 and -3.6 MPa) which were made of polyethylene glycol 6000 and second in salinity stress included 13 levels of sodium chloride concentration that was iso-osmotic with first experiment (Zero, 62, 122, 187, 249, 311, 368, 435, 498, 560, 622, 684 and 745 mM). After the end of the germination period, the characteristics of germination rate and percentage were calculated and the hydrotime model was used to describe the relationship between germination and water potential, and the halotime model was used to describe the relationship between germination and salinity. To select the best model among the osmotic potentials, root mean square parameters and R2 were used.

The results of mean comparison of effect of osmotic potentials on the percentage of germination showed that in PEG and NaCl treatment, it was almost 100% up to the level of -1.2 and -1.5 MPa, respectively, and after that, a decreasing trend was observed, so that at the level of -3.3 MP showed a decrease of about 90 and 85%, respectively. The output results of the models showed that the coefficient of the hydrotime and halotime models were 96.8 MPa.h and 16181.87 mM.h, respectively, and the drought and salinity tolerance thresholds were -3.28 MPa and 714.62 mM, respectively. The halotime model quantified the germination of Salicornia seeds better than the hydrotime model. Drought stress limits the absorption of water by seeds and affects germination by reducing the movement and transfer of seed reserves or by directly affecting the structure and synthesis of protein in the embryo. Salinity increases the osmotic pressure of the solution and reduces water absorption through the seeds. On the other hand, high salinity causes toxicity and disturbs the ionic balance and reduces seed germination by affecting the vital interactions of the seed.

The rate of decrease in germination rate and percentage in drought stress was higher than salinity stress. Based on the results of this study, using the halotime model in biological studies of halophyte plants under osmotic stress, the tolerance threshold and the time required for germination at different salt concentrations can be well determined.

One of the most important factors in reducing vigor of seed is the occurrence of water stress during seed development on mother plant. Also, the use of growth regulators in environmental stresses leads to the production of seeds with better germination ability. In order to study the effect of methyl jasmonate on germination indices and vigor of two bread wheat cultivars under different irrigation regimes, an experiment was conducted as a split factorial in a RCBD design in two growing seasons (2015 and 2017). In this experiment, different irrigation regimes including normal irrigation (control), irrigation cut off from bolting stage and irrigation cut off from the grain milking stage were investigated as the main factor, and two wheat cultivars Sirvan and Pishtaz and 0, 50, 100, and 150 μm of methyl as sub plots. The results showed that in both cultivars, germination indices decreased by stress, but application of 100 μM methyl jasmonate increased the germination percentage, germination rate, length and weight vigor, gluten and seed starch content in both years compared to the control. On average, at different levels of irrigation cut off and full irrigation, Sirvan cultivar showed higher germination percentage and rate than Pishtaz cultivar. Also, irrigation cut off from bolting stage had the greatest negative effect on the seed formed in the mother plant in different wheat cultivars. Overall, the results showed that among the treatments, the best methyl jasmonate application with a concentration of 100 mM was able to moderate the effects of drought stress and improve germination and qualitative traits of seed under stress and non-stress conditions and Sirvan had higher seed quality.

Heavy metals, including nickel, are among the most important pollutants. Ni as a micronutrient is essential for plants, however, with increasing concentrations of nickel in the environment, excess of the element accumulated in plants and causing toxicity. Phytoremediation is a biotechnology, using the plant to remove or reduce environmental pollutants. In this study, to evaluate the nickel phytoremediation potential and accumulation, the effects of different levels of nickel on some growth and development characteristics of Mentha longifolia L., were studied. Various concentrations of nickel (0, 10, 50, 100 and 300 mg/l) were treated in hydroponic culture, and in this condition, the plant potential for nickel tolerance and nickel effects on some physiological and morphological characteristics of M. longifolia were evaluated. Experiments were conducted in a completely randomized design. Results analysis showed that characteristics: shoot and root length, leaf area, shoot and root dry weight, total chlorophyll, carotenoid, anthocyanins and soluble carbohydrates content of the plant were reduced by increasing the concentration of nickel in nutrient solution but total protein and shoot and root nickel content were increased. Overally, based on evaluating of the effects of nickel on vegetative and physiological characters of M. longifolia, in this study, it can be acknowledged that the plant is not resistance to nickel stress, and is not suitable for phytoremediation and removing excess amounts of nickel in the environment. Also, due to the sensitivity of the plant to nickel stress, it can be counted as an indicator of environmental nickel pollution.

Canola (Brassica napus L.) is one of the important oil plants in temperate regions, which has great value for humans and livestock as a producer of oil and meal. Phosphorus plays an important role in improving the quality and quantity of oilseeds, including rapeseed. Sufficient sources of phosphate are needed by the plant for earlier development and rooting and more foliage production in a short period of time. Considering the stabilization of phosphorus in the soil, the increase in the price of chemical fertilizers and environmental pollution, the use of biological fertilizers, especially the types of phosphorus-dissolving bacteria, play an important role in solving these problems. Therefore, the objective of this research was to investigate the role of phosphorus biofertilizer containing Pseudomonas fluorescens bacteria in improving the quantitative and qualitative yield of canola under the influence of chemical phosphorus fertilizer management.

A factorial field experiment was conducted based on a randomized complete block design with three replications at the research station of the Faculty of Agriculture of Yasouj University located in Deshtrum region in 2019. The first factor was triple superphosphate fertilizer at 6 levels (zero, 25, 50, 75, 100 and 125 kg/ha of pure phosphorus) and the second factor included phosphorus biological fertilizer containing Pseudomonas fluorescens bacteria at two levels (application and non-application). The traits of yield components, seed and biological yield, and seed oil and protein were evaluated. The traits of yield components, seed and biological yield, and seed oil and protein were evaluated. Yield components, seed and biological yield, and seed oil and protein were evaluated.

The results showed that phosphorus and bacteria chemical fertilizers had a significant effect on all investigated traits. The interaction of phosphorus chemical fertilizer and bacteria was also significant on all investigated traits except harvest index. The highest plant height (124.93 cm), number of lateral branches (4), leaf chlorophyll index (74.20), seed yield (5887 kg/ha) and biological yield (19411.4 kg/ha) were obtained in the treatment of 125 kg/ha of phosphorus and bacterial application. Also, with the consumption of 125 kg/ha of phosphorus fertilizer and the use of bacteria, the highest percentage and oil yield was obtained. Also, the results showed that there is no significant difference between the treatment of application of 50 kg of phosphorus fertilizer + bacteria and the treatments of application of higher levels of phosphorus fertilizer (75, 100 and 125 kg) alone.

Considering the superiority of 125 kg of phosphorus fertilizer along with bacteria in terms of grain yield, oil percentage and oil yield, it seems that these amounts of phosphorus fertilizer as well as the use of bacteria can be used to achieve proper yield in the experimental and also similar areas. Also, the results show that using bacteria can reduce the consumption of phosphorus chemical fertilizers.

Beans are one of the most important food sources in many parts of the world due to their high protein content. According to geographical conditions, drought stress in Iran is one of the most important threats to agricultural products. Disruption of photosynthesis, destruction of cell structures, reduction of stomatal conductance and plant growth are among the effects of drought stress. Today, the use of biofertilizers based on soil microorganisms is one of the main goals of sustainable agriculture to improve plant condition. In addition to improving soil structure, biofertilizers improve plant growth and yield under stress conditions by increasing root morphology, increasing nutrient uptake and increasing antioxidant power. Due to the negative effect of drought stress on crop yield, an experiment was conducted to investigate the effect of biofertilizers on physiological characteristics and grain yield of red beans in different irrigation regimes.

  This experiment was performed as a split plot base on randomized complete block design with three replications in the research farm of Yasouj University in 2016. Experimental treatments include irrigation at three levels (normal irrigation, irrigation cut-off at the beginning of flowering to the beginning of podding and irrigation cut-off at the beginning of podding to maturity) and biofertilizer at four levels (control (no application) Biofertilizer (application of mycorrhiza fungus, phosphorus solubilizing bacteria and combined application of mycorrhizal fungus and phosphorus solubilizing bacteria). The red bean seed (phaseolus vulgaris) used in this experiment was a Derakhshan cultivar and the mycorrhizal fungus used was Funneliformis mosseae. Phosphorus solubilizing bacteria (Phosphate barvar2) base on Pseudomonas putida Strain P13 and Pantoea agglomerans Strain P5 were used as seed inoculation at planting time. Sampling was done randomly at the beginning of podding stage and in the middle of grain filling with respect to the marginal effect in each block in order to measure percentage of electrolyte leakage, leaf relative water content (RWC), content of photosynthetic pigments, soluble sugars, proline and malondialdehyde (MDA).

  The results showed that different levels of irrigation were significant for traits such as RWC, electrolyte leakage percentage, MDA content, leaf proline content, leaf protein, soluble sugar concentration, total chlorophyll content and carotenoids. The effect of biofertilizer was significant on all traits except the RWC. It should be noted that the interaction of irrigation and biofertilizer was not significant on any of the studied physiological traits except for MDA. Irrigation levels and application of biofertilizers also had a significant effect on grain yield, the combination of both biofertilizers was very effective on grain yield, especially in stress conditions. The grain yield was more than control in the case of irrigation cut-off in the flowering stage and in the case of irrigation cut-off in the stage of podding to maturity by 45 and 38%, respectively.

The results of this experiment showed that drought stress in the form of irrigation cut-off reduced the concentration of photosynthetic pigments, increased the levels of physiological degradation and thus reduced the grain yield of red beans. In conditions of drought stress application of mycorrhiza biofertilizers and phosphorus solubilizing bacteria, by reducing the damage caused by drought stress, prevented the reduction of bean yield. Also, the application of biofertilizers in normal conditions significantly increased the yield of red beans.

In order to investigate the effect of chemical and biological nitrogen fertilizer on canola, a field experiment was conducted as a split plot based on a randomized complete block design with three replications at the research station of the Faculty of Agriculture, Yasouj University, located in Deshtrum region, in 2019. The main factor consisted of nitrogen fertilizer (zero, 25, 50, 75, 100 and 125 kg/ha of pure nitrogen from urea source) and the secondary factor consisted of nitroxin biofertilizer contained Azotobacter and Azospirillium bacteria (use and non-use). The results showed that nitrogen fertilizer and nitroxin had a significant effect on all investigated traits. Nitrogen fertilizer significantly increased plant height, number of lateral branches, chlorophyll index and oil yield. The highest grain (8790.60 kg/ha) and biological (23910.93 kg/ha) yield were obtained in 125 kg/ha of nitrogen and the use of nitroxin. With the consumption of 125 kg/ha of nitrogen and nitroxin, the lowest percentage of seed oil, and contrastingly the highest percentage of seed protein (36.65%) was obtained. In general, combined application of biofertilizer with chemical nitrogen increased grain, biological and oil yield. Nitroxin bio-fertilizer could reduce the consumption of chemical nitrogen fertilizer. The results showed that there was no significant difference between the application of 50 kg/ha of nitrogen + bacteria and the application of higher levels of nitrogen (75, 100 and 125 kg/ha) alone in most of the investigated traits.

Germination and seedling establishment are sensitive and important stages in the life cycle of plants that are affected by abiotic stresses, especially drought and salinity stresses. This study was conducted to investigate the effects of osmotic potential (due to sodium chloride and polyethylene glycol) on germination and biochemical indices of Salicornia sinus-persica Akhani spec. nov.Akhani seeds in 2020 in the Agriculture Laboratory of Yasouj University of Agriculture in a completely randomized design with three replications of 50 seeds. A separate experiment was performed in which the first experiment consisted of 13 levels of osmotic potential (zero, -0.3, -0.6, -0.9, -1.2, -1.5, -1.8, -1.2, -2.4, -2.7, -3, -3.3 and -3.6 MPa) which were made of polyethylene glycol and the second experiment included 13 salinity stress levels with osmosis similar to the first experiment (zero, 62, 122, 187, 249, 311, 368, 435, 498, 560, 622, 684 and 746  mM) were used to make sodium chloride. The results showed that the trend of salicornia seed germination indices in salinity and drought stresses had a constant trend up to the level of about -1.2 (249 mM) and -0.6 MPa, respectively, and then with a decrease in the osmotic potential of germination percentage, root and stem length, root and shoot dry weight and seedling vigor length and weight index showed a decreasing trend so that the slope of this decreasing trend was higher in drought stress compared with salinity stress. From osmotic potential of 1.2 MPa onwards, in salinity thirst, seed biochemical parameters such as proline content, malondialdehyde content and sodium element increased whereas potassium element decreased and in drought stress, proline and malondialdehyde content showed an increasing trend. In general, Salicornia seeds were more sensitive to drought stress than salinity stress.

In order to investigate some characteristics of German chamomile (Matricaria chamomilla) under water stress and application of  mycorrhizal, an experiment was performed in factorial arrangement within a completely randomized design with four replications in research greenhouse of the Faculty of Agriculture at Yasouj University. The first factor was osmotic potential at three levels (zero, -4 and -8 bar), the second factor was the application of arbuscular mycorrhizal fungus Funneliformis mosseae at two levels (with and without the use of fungi) and the third factor was cultivars at two levels (Bodegold and Soroksari). The studied traits included: (relative water content, soluble sugars, proline content, total chlorophyll, plant height, number of flowers per plant, Shoot dry weight, dry weight of flowers and harvest index). The results showed that osmotic potential at -4 and -8 bar caused a significant reduction in traits such as total chlorophyll, relative water content, plant height, number of flowers per plant, dry weight of shoot, dry weight of flowers and index harvested, but the amount of soluble sugars in the leaves and the content of proline increased. Mycorrhizal application increased the amount of these traits. Also, inoculation of mycorrhiza plants under drought stress conditions significantly increased proline content and soluble sugars of both cultivars. The results showed that the key trait of flower yield and yield components under drought stress and application of mycorrhiza in Soroxari cultivar showed more increase than Budgold cultivar. In general, application of mycorrhiza in both cultivars increased drought stress resistance in German chamomile.

Saffron is propagated exclusively by corm because of sterility. Therefore, choosing the suitable corm for cultivation is one of the important factors in saffron production and the final yield depends on the size of the corm. The research was conducted to investigate the effects of benzyl aminopurine hormone priming, application of bio-fertilizers and maternal corm weight on the germination indices of saffron cormlets. Experimental treatments consisted of large (7.1-10 g) and small (4-7 g) corms, priming with benzyl aminopurine at concentrations of 0, 250, and 500 mg/l and biofertilizer levels (no fertilizer, Mycorrhiza (Funneliformis mossea) and fertilizer, Phosphate Barvar2). The results showed that maternal corms with 7.1 to 10 g compared to 4 to 7 g increased seedling emergence rate by 14% and the seedling vigor length index by 6.3%. Hormonal priming of maternal corms with a concentration of 500 mg/l increased dry weight leaf of main and lateral shoots (34%), dry weight of the main and total shoots (37% ), and also improved emergence rate (56%) and the number of the contractile root of cormlet (77%) with biofertilizer application. The interaction of hormonal priming (250 mg/l) and the use of maternal corms with 7.1 to 10 g increased the weight index of seedling vigor by 72%. Biofertilizer treatment increased 25% of the total dry weight of the shoots. In general, the application of larger corms and the application of biofertilizer and hormonal priming improved cormlet and saffron seedling vigor.

Schrophularia striata is one of the medicinal plants of the Scrophulariaceae family and contains phenolic compounds. Locals have traditionally used this herbal medicine to treat infections caused by wounds, gastrointestinal diseases, and eye diseases. Due to excessive consumption by indigenous people and climate change, especially increasing temperature, the cold required to eliminate seed dormancy is not presently available and its germination and growth has decreased. Therefore, this plant is at the risk of extinction. Since this plant is propagated in natural habitats through seed and due to deep seed dormancy, evaluation of different seed dormancy methods is necessary for conservation and domestication of this species. In this study, suitable methods to eliminate seed dormancy of this plant using chilling and gibberellic acid treatments were studied on the seeds collected from different habitats of Ilam province.

To investigate the effect of using chilling and gibberellic acid on Schrophularia striata dormancy, a split plot factorial experiment based on completely randomized design with four replications was conducted at the seed laboratory of Yasouj University in 2018. The first factor included the duration of moist chilling period (0, 4, 8, 12 and 16 weeks), the second factor included gibberellic acid (0, 300 and 600 mg/L) and the third factor included five habitats (Ilam, Ivan, Mehran, Abadan and Dehloran).

The results showed that the 16-week Chilling and zero gibberellic acid treatments had the highest germination percentage in all habitats, as the percentage of germination in Mehran, Ivan, Ilam, Abadan and Dehloran habitats was 66, 50, 36, 30 and 25%, respectively. Also, the highest germination rate was observed in all habitats at 16 weeks chilling and zero mg/L gibberellic acid concentration. The highest germination uniformity was obtained at 16 and 12 weeks of chilling.

Chilling period duration was effective on germination percentage and rate and with increasing chilling period, germination percentage and rate increased. This indicates that the seeds studied had some degree of physiological dormancy, and the seed of higher altitude habitats required longer chilling periods than those of the lower ones for germination. Also, according to the results of this experiment, chilling periods above 16 weeks should be used to increase germination percentage.

Climate change may contribute to drought stress and limit crop production. The oilseed rape (Brassica napus L.) cultivation area has declined due to drought stress. Identification of high-yielding and tolerant varieties could be regarded as a solution to this problem. Twelve oilseed rape genotypes were planted under drought stress and normal conditions in Lishtar, Gachsaran, Iran, using a randomized complete block design with three replications in 2017. A considerable decline in the pods per plant (76%), pod length (20%), grain yield (80%), biomass (73%), harvest index (37%), plant height (34%), seeds per pod (41%) and branches per plant (41%) of genotypes was observed in the evaluated genotypes of the oilseed rape as the consequence of drought stress. In general, grain yield, biomass, and pods per plant had a very high sensitivity to moisture reduction. The significant direct effect of the pod number and 1000-seed weight on the grain yield showed that these characteristics can be used to select the promising genotypes to increase the grain yield of oilseed rape under normal conditions. Under drought stress conditions, branch number per plant, pod length, and seeds per pod had a significant direct effect on grain yield. Increasing these traits and reducing the plant height and shortening the growth period may improve the grain yield of the oilseed rape. Hyola401, RGS003, and Hyola308, showed the highest grain yield under both drought stress and normal conditions among the evaluated oilseed rape genotypes. They may be regarded as the promising varieties to be planted in the conditions of the experimental site or similar areas.

In order to investigate the effect of biofertilizer on physiological characteristics and nutrient concentration in linseed under irrigation withholding at different growth stages, a farm experiment conducted as split plot base on randomized complete block design with three replication at research field of Yasouj University in 2017. Irrigation regimes (full irrigation, irrigation withholding at beginning of flowering until beginning of podding, irrigation withholding at beginning of podding to end of maturity) and bio-fertilizer application at four levels (mycorrhiza fungi, Phosphate Barvar2, mycorrhiza arbuscular fungi + Phosphate Barvar2 and non-application of bio-fertilizer) were considered as the main and the sub plots, respectively. The results showed that the highest concentration of phosphorus (8.27 g.kg-1) and potassium (4.20 g.kg-1) in the leaf was observed in the treatment of mycorrhiza bio-fertilizer. In both stages of flowering and seed filling, irrigation withholding compared to full irrigation increased the soluble sugars, malondialdehyde, but reduced the relative water content and soluble protein of leaf.  The highest leaf prolin cintent (11.63 µmol.g-1) was observed in both biofertilizer combination treatments in condition of Irrigation withholding at beginning of podding to end of maturity. Application of both type of biofertilizer increased soluble sugar concentration, soluble protein and reduced malondialdehyde levels. The highest grain yield was observed from application of mycorrhiza+ phosphate Barvar2.The results indicate that linseed is sensitive to drought stress in the encapsulation to ripening stage (58% reduction). This damage modified by application of biofertilizer trough improving the absorption of nutrients and changing the concentration of osmolites.

Iran, is classified as arid and semi-arid regions of the world. Therefore, it is important to identify and planting of drought tolerant plants such as quinoa (Chenopodium quinoa Willd.). Zinc is involved in vital processes of the plant therefore; the supply of this element to the plant has a major impact on the quantity and quality of production. This study was conducted as a pot experiment to investigate the effect of zinc sulfate on quinoa under drought stress in a factorial randomized complete design with three replications. Drought stress was prepared with PEG 6000 at four levels (0, -3, -6 and -9 bar) and zinc element from zinc sulfate source with four levels (2 (control), 4, 6, and 8 μM) and in the four-leaf stage, the treatments were applied simultaneously to Hoglandchr('39')s nutrient solution for two weeks. According to the results, an increase in drought stress caused a 68% increase in catalase compared to the control. Maximum leaf soluble protein at -6 bar level with 8 μM zinc sulfate level, highest total soluble sugars and leaf proline at the highest level of drought and 6 μM zinc sulfate were observed. With increasing drought, chlorophyll a (34%), chlorophyll b (187%) and leaf carotenoid increased two-fold but decreased shoot dry weight (38%) and leaf area (37%) compared to control. In general, the use of zinc reduced the damage caused by drought stress by improving the level of osmolytics, and to alleviate the effect of drought stress, the use of 6 μM zinc sulfate in nutrient solutions is recommended.

The goals of study were to evaluate the competitive and economic indices of Kochia, Sesbania and Guar intercropping to select the best cultivation system in conditions of salinity stress.

This experiment was performed at the National Salinity Research Center (NSRC) Yazd-Iran in 2016 and 2017. Three replicates of this split-plot experiment was done using randomized complete block design. The main factor was salinity stress at three levels (irrigation with 4, 9 and 14 dS/m electrical conductivity) and sub-factor, cultivation systems (three sole cropping of Kochia, Sesbania and Guar and their two and three species intercropping.

The results showed that salinity decreased the height of Sesbania and Guar and the mixed cultivation maintained the height of Guar and reduced leaf temperature. The highest percentage of green cover was at 4 and 9 dS/m in three Species, but at 14 dS/m in Kochia sole cropping which had no significant difference with three species. By increasing the salinity from 4 to 14 dS/m, the leaf chlorophyll index of the Guar decreased 21.9% and Sesbania 11.4%, respectively. Intercropping of the three species increased the leaf chlorophyll concentration. The use of mixed cultivation increased the yield of Guar and Sesbania.

Due to the four advantage indices and Relative Value Total at the three salinity levels (1.16, 1.08 and 1.01), it is recommended to replace Kochia sole cropping by three species intercropping.

To investigate physiological responses of black cumin to calcium silicate under salinity and drought stress condition with iso-osmotic potentials, a factorial experiment carried out based on the completely randomized design with three replications in research greenhouse of Faculty of Agriculture, Yasouj University, Iran in 2018. The first factor consisted of seven levels (salinity and drought stresses with iso-osmotic potentials of -2.4, -4.9 and -7.4 bar and control treatment) applied in Hoaglandchr('39')s solution. Salinity was applied with sodium chloride (NaCl) and drought with polyethylene glycol 6000 (PEG 6000). The results showed that at calcium silicate levels, salinity and drought stresses increased catalase and peroxidase activity, proline soluble sugars and malondialdehyde and also decreased leaf relative water content and leaf chlorophyll content. Silicate application mitigated the stress effects so that increased catalase and peroxidase activity, chlorophyll, proline and soluble sugars and decreased malondialdehyde content. In iso-osmotic potentials of drought compared with salinity, relative water content decreased but proline content, soluble sugars content, malondialdehyde content and catalase activity increased, indicating that black cumin sensitivity to drought is more than salinity based on physiological traits.

Saffron is one of the most important crops and medicinal plants in Iran. The research was accomplished in order to investigate the effects of Benzyl aminopurine hormone treatment, application of bio-fertilizers (Phosphate Barvar2 and mycorrhiza) and maternal corm weight on the quantitative indices of saffron cormlets and flowers yield as a factorial based on randomized complete block design with three replications was conducted in Yasouj region. Experimental treatments consisted of large (7.1-10 g) and small (4-7 g) corms, priming with benzyl aminopurine at concentrations of 0, 250 and 500 mg/l and biofertilizer levels (no fertilizer, Mycorrhiza (Glomus mossea) and fertilizer, Phosphate Barvar2) were used. The results showed that all quantitative traits of saffron corm were significantly affected by hormonal priming and maternal corm weight (except for corm weight); But biofertilizer had only significant effect on corm number and flower dry weight. The Hormonal priming at a concentration of 250 mg/l increased the number and weight of corms by 30 and 27%, respectively, and the dry weight of stigma and filament by 26% compared to control. Also, all flower components and number of corms were significantly increased by using larger maternal corms than small corms. The use of bio-fertilizers as compared to no fertilizer increased 13 and 59% corm number and weight, respectively. Phosphorus and zinc content in corms increased only under the influence of mycorrhiza fertilizer application. Whereas, with the use of benzyl aminopurine and mycorrhiza fertilizer, the iron content increased twice as much as the control. Generally 250 mg/l application of benzyl aminopurine, bio-fertilizers and larger corms (7.1-10 g) it had a positive effect on most of the measured traits

It is important to determine the optimum nitrogen and plant density to increase linseed quantitative and qualitative yields, nutrients uptake and nitrogen use efficiency. Therefore, this experiment was conducted to achieve the best nitrogen and plant density combination in linseed. The experiment was conducted in Yasouj University, Iran, as a split plot based on a randomized complete block design with three replications in 2016. Treatments were nitrogen as main factor in five levels (0, 25, 50, 75 and 100 kg N ha -1) and density as sub factor in three levels (50, 100 and 150 plant m-2). Maximum seed oil yield (982 Kg ha-1), seed yield (2525 Kg ha-1), grain protein (33.5 %),  seed mucilage (7.4%), seed phosphorus (0.41% ) and potassium (2.85%) were obtained from 100 kg N ha-1 at the density of 100 plants m-2. Maximum nitrogen use efficiency (79.5 kg kg-1) was obtained in 25 kg N ha-1 and 150 plants m-2 treatment, however the minimum (20.4 kg kg-1) obtained from minimum plant density and maximum nitrogen. Generally it is suggested the 100 plant m-2 density and 100 Kg ha-1 nitrogen to produce high linseed yield quantity and also quality in Yasouj region.

Melatonin (N-acetyl-5- methoxytryptamine) as a plant growth regulator, natural compound that is in a large variety of plant species in roots, leaves, fruits and seeds have been identified. In order to investigate the effect of melatonin on some physiological characteristics of chickpea seed and seedling (Arman cultivar) under salinity stress, a factorial experiment was conducted based on a completely randomized design with four replications in 2017 at the Yasouj University. The factors included melatonin at concentrations of without-prim, 0, 25, 50, 75, 100 and 125 μM as the first factor, and different levels of salinity include 0, 25, 50, 75 and 100 mM sodium chloride, as the second factor. The results showed that in salinity levels of 100 and 50 mM, melatonin with concentration of 100 μM increased the seedling proline. In non stress conditions, priming with 25, 75 and 100 μM melatonin increased seedling potassium content. Also, in 100 mM salinity stress, priming with 50 and 75 μM melatonin increased potassium content in the seedling. Priming reduced the sodium content of seedling at salinity levels of 100 and 75 mM by 25 and 75 μM melatonin concentrations respectively. Overall, the results of this study showed that chickpea tolerate salinity stress at germination stage up to 100 mM, and the use of melatonin at these stage due to salinity tolerance has not a significant effect on the physiological indices of the seeds, and only hydropriming in this condition compared to non-primed by helping to absorb water by the plant has had a positive effect on the physiological process during germination.

Quinoa (Chenopodium quinoa Willd.) is a plant from Amaranthaceae family that now considered an alternative to high-water plants, its high nutritional value and high adaptability to tolerate a wide range of biotic and abiotic stresses. Among the nutrients, nitrogen is the most important element that restricts plant growth and plays an important role in enhancing the quantitative and qualitative yield of crops. Selection of optimal crop density due to competition over water, food and light is one of the most important crop factors that has a significant impact on crop growth and yield. Due to the welcoming of farmers in Fars province for the development of cultivation of quinoa, this study was conducted to evaluate the interaction of nitrogen fertilizer and plant density on the growth and yield of quinoa in Mamassani city of Fars province.

The experiment was conducted as split plot based on randomized complete block design with three replications in September 2018 in Mamassani city of Fars province. The main factor was nitrogen fertilizer at four levels (0, 60, 120 and 180 kg ha-1 from urea source) and the sub-factor was planting density at three levels (60, 80 and 100 plants m-2). The harvesting operation was carried out on December 10. In this experiment, plant height, number of lateral branches and length of panicle were measured through 5 randomly sampled plots. For determination of biological yield and grain yield, two square meters of each unit were harvested with respect to marginal effect. In order to estimate growth indices, two middle rows from the middle of each plot were removed by liminating the marginal effect. The first sampling was performed 14 days after planting and subsequent sampling was performed at intervals once evry 14 days until the end of plant growth.

The results showed that nitrogen fertilizer had a significant effect on increasing plant height, number of lateral branches and panicle length. Increasing plant density decreased the number of lateral branches and the length of panicle. Increasing nitrogen and plant density increased plant height, grain yield, biological yield and 1000 grain weight. The highest leaf area index, crop growth rate and total dry matter accumulation were obtained at the highest level of fertilizer and plant density.

Due to the superiority of 180 kg of nitrogen level and density of 100 plants per square meter in terms of grain yield, harvest index, leaf area index and crop growth rate, it seems that these amounts of nitrogen fertilizer and planting density can be recommended for proper performance in the test area and similar areas.

In order to investigate the effects of different levels of supplementary irrigation and bio-fertilizers on some physiological traits, yield, and essential oil percentage of medicinal plant cumin (Cuminum cyminum L.), an experiment was conducted as split-plot in a randomized complete block design with three replications in the research field of Kohgiluyeh and Buyer-Ahmad Agricultural and Natural Resources Research and Training Center in 2017. The main plot included supplementary irrigation (complete rainfed conditions, supplementary irrigation at 50% flowering and at the start of seed formation) and the subplot included bio-fertilizer (no phosphorus bio-fertilizer, mycorrhiza Glomus mosseae, phosphorus bio-fertilizer, and combination of mycorrhiza and phosphorus bio-fertilizer). The application of supplementary irrigation with bio-fertilizer increased the total chlorophyll and carotenoid and decreased the proline content. Phosphorus bio-fertilizer also increased catalase enzyme activity in the plant. The effects of supplementary irrigation and phosphorus bio-fertilizer on the number of umbrella per plant, plant height, 1000-seed weight and the number of seeds per umbrella were significant. The highest amount of 1000-seed weight (2.55 g), seed yield (622.4 kg ha-1), biological yield (1252 kg ha-1), and essential oil percentage (54.86%) was obtained in the mycorrhiza treatment together with the phosphorus bio-fertilizer. In general, the results showed that using phosphorus bio-fertilizer, mycorrhiza, and supplementary irrigation can improve physiological traits, yield, and essential oil of cumin under rainfed conditions.

In order to evaluate the effect of different bio-fertilizer on agronomical traits and photosynthesis pigments of linseed under irrigation cut-off condition a farm experiment carried out as split plot base on randomized complete block design with three replication at research field of Yasouj university in 2017. Irrigation regimes at three levels, full irrigation, irrigation cut-off at beginning of flowering until beginning of podding, irrigation cut-off at beginning of podding to end of maturity and bio-fertilizer application at four levels as mycorrhiza arbuscular fungi, Phosphate Barvar2, mycorrhiza arbuscular fungi+Phosphate Barvar2 and non-application of bio-fertilizer were considered as the main and the sub plots, respectively. Results showed that the lowest grain and oil yield (93.7 and 32.9 g.m-2) and the lowest  capsule numbers per plant, seed numbers per capsule and 1000 seed weight and also the highest seed protein percent were achieved from irrigation cut-off at  beginning of podding to end of maturity. Application of mycorrhiza arbuscular fungi + Phosphate Barvar2 comparison with non-application of bio-fertilizer increased capsule numbers per plant, grain and oil yield, and protein percent by 25.5, 26.5, 33.1 and 17.4 percent respectively. Use of mycorrhiza arbuscular fungi + Phosphate Barvar2 under irrigation cut-off at beginning of podding to end of maturity increased leaf carotenoid content significantly in seed filling stage sampling. Also in full irrigation condition at beginning pooding stage sampling, Use of mycorrhiza arbuscular fungi + Phosphate Barvar2 increased leaf chlorophyll content significantly.