جستجوی مقالات مرتبط با کلیدواژه « Oil percentage » در نشریات گروه « زراعت »

AbstractIn order to investigate the effect of different levels of zeolite and defficit irrigation on some physiological traits, oil and protein yield of lineeed crop, in a split plot experiment were conducted in based on a randomized complete blocks design with three replications  in Shahrekord University in 2016. Defficit irrigation as the main factor in four levels, including 50 (control), 80, 130 and 180 mm of evaporation from the class A evaporation pan, and the use of zeolite as a secondary factor in three levels, including non-use (control) and the use of 5 and 10 tons/hectares were considered. The results of the experiment showed that the application of zeolite at a probability level of 1% had a significant effect on the content of chlorophyll a, chlorophyll b, total chlorophyll and carotenoids of leaves, oil yield, nitrogen percentage, protein percentage and seed protein yield, allthogh, the oil percentage was not affected by this treatment. Also, different levels of irrigation were significant on all the mentioned traits at the level of 1%. The interaction of the simple effect of the treatments on protein percentage, nitrogen percentage, chlorophyll a and total chlorophyll was significant at the 1% probability level and on oil yield and chlorophyll b at the 5% probability level, and showed non-significance on the oil percentage, protein yield and carotenoid . The highest amount of the above traits was obtained from the control treatment (normal irrigation) and the application of 10 tons zeolite /hectare, and the lowest amount of the traits was obtained from the treatment of 180 mm of evaporation from the evaporation pan and no application of zeolite. The results showed that the application of zeolite has significantly improved the performance of the lineeed crop in non-stress conditions to moderate drought stress conditions.IntroductionOilseeds are big sources of energy and protein. Linseed (Linum usitatissimum) is an oilseed crop with a history of several thousand years of cultivation, which seeds contain 30 to 50% edible oil. Linseed is a one-year herbaceous plant belonging to the Linaceae family, which is believed to have originated in the western Mediterranean (Omidbeighi, 2014). The protein content of linseed seeds is between 29-44%. It has been reported (Iran-Nejad, 2014). Water defficit is one of the significant and important stresses affecting the growth, development and functions crops. Water stress in plants may lead to physiological disorders such as reduction of photosynthetic pigments, reduction of assimilates. and reduce growth (Petropoulos et al., 2008). water stress reduces the absorption of nutrients through the roots due to the reduction of soil water and the reduction of the distribution of nutrients in the soil tissue; it also reduces the transfer of nutrients from the roots to When plants are under stress, their chlorophyll content decreases and as a result, photosynthetic activity also decreases in plants under stress.Materials and MethodsThe field experiment has been conducted as a split plot based on a randomized complete block design with three replications at the research farm of Shahrekord University on linseed crop in 2016. The main factor water stress included four levels of 50 (control), 80, 130, the lowest irrigation level and 180 mm of evaporation from the evaporation pan, and the secondary factor of zeolite consumption in three levels, including control (without zeolite), 5 and 10 tons of zeolite per hectare. The traits of chlorophyll concentration (a, b and total), yield and yield components, thousand seed weight, oil percentage, seed oil yield, seed nitrogen percentage, protein percentage and seed protein yield were measured.Results and DiscussionThe experiment results showed that the application of zeolite on chlorophyll a, chlorophyll b, total chlorophyll and carotenoid, oil yield, nitrogen percentage, protein percentage and seed protein yield was significant at the probability level of 1% and it was not significant on oil percentage. Also, different irrigation levels were significant on all the mentioned traits at the level of 1%. The interaction effect of treatments on protein percentage, nitrogen percentage, chlorophyll a and total chlorophyll was significant at one percent probability level, and on oil yield and chlorophyll b at five percent probability level. It was not significant on oil percentage, protein yield, and carotenoid. The results showed that deficit irrigation reduced all investigated traits. So that the maximum amount of the above traits were obtained from the control treatment (normal irrigation) and the application of 10 tons of zeolite per hectare, and the lowest amount of traits was obtained from of 180 mm evaporation from the evaporation pan and the absence of zeolite application. The results showed that the use of zeolite, has significantly increased the yield of linseed crop under non-stress conditions to moderate drought stress conditions, but under severe stress conditions, the limiting effects of drought stress have significantly reduced the studied traits.ConclusionThe results showed that the use of zeolite, due to its property of absorbing water, maintaining and increasing the availability of moisture, reduces the intensity of drought stress and moderates the destructive effects of drought stress on the content of chlorophyll, carotenoid, and protein in plants. In this research, it was found that the use of 10 tons of zeolite per hectare had a favorable effect on reducing the damage caused by drought stress in linseed crops, and considering the abundance of zeolite in different parts of the country and its reasonable economic price, as well as, the problem of drought stress in Iran, the use of Zeolite can improve plant access to soil water and increase yield and quality of oil and protein of linseed under water deficit conditions.

Salinity is one of the major abiotic stresses and the most limiting factor in agricultural production worldwide, affecting the growth, development, and final yields of crops. Rapeseed is one of the most important sources of oilseeds in the world, and its seeds contain more than 40% of oil. Moreover, the meal obtained from oil extraction has more than 35% protein, hence it currently ranks third among oil crops in the world after soybean and oil palm, making it necessary to identify the genotypes that tolerate salinity stress. The development and improvement of rapeseed cultivars with salinity tolerance and acclimation offer promising prospects for improving sustainable production in this area. Therefore, the current study aimed to investigate the responses of rapeseed genotypes to salinity stress through analyses of agronomic and biochemical traits.

The genetic diversity between rapeseed lines in terms of agronomic, morphological, and physiological traits in saline soils was investigated in an experiment based on a randomized complete block design with 17 autumn rapeseed genotypes with three replicates in the research farm of East-Azarbaijan Agricultural and Natural Resources Research and Education Center. The measured traits were plant height, the number of fertile pods, number of seeds per pod, pod length, pod area, plant growth rate, 1000-seed weight (TSW), seed yield, oil content, and oil yield. The relationships between yield, yield components, and morphological traits were explored using the analysis of variance (ANOVA), comparison of averages, correlation analysis, cluster analysis, and biplot to understand the relative importance of traits affecting the yield of the studied genotypes.

The studied genotypes were significantly different from each other in pod length, pod area, number of fertile pods, number of seeds per pod, plant growth rate, seed oil percentage, plant height, TSW, grain yield, and oil yield. However, there were no significant differences between the studied genotypes in terms of harvest index and number of actual pods to potential pods. According to the mean comparisons, genotypes 5, 11, and 15 can be introduced as salinity-tolerant lines, and genotypes 2, 4, 6, 9, and 12 can be considered salinity-sensitive lines. According to the other traits, genotype 11 produced a high pod length, number of fertile pods, oil percentage, and oil yield, genotype 5 had a high growth rate and oil percentage, and genotype 15 presented a high height and number of fertile pods. According to the cluster analysis, the second and third groups contained tolerant and susceptible genotypes, respectively. The genotypes in the second group had the highest percentage of positive deviation from the overall mean for grain yield, plant height, harvest index, seed oil percentage, pod length, pod area, and number of fertile pods. Based on the biplot analysis, Karaj 8 and 14 genotypes had a strong relationship with the number of  fertile pods, number of seeds per pod, pod length, pod area, and plant growth rate. Based on the obtained results, the plant height, TSW, seed yield, and oil content traits were closely correlated with Karaj 5, 7, 11, 10, and 15 genotypes. Based on the results of correlation analysis, the correlation coefficient of seed yield was positive and significant for three traits, i.e., plant height, oil percentage, and number of fertile pods, and the highest correlation coefficient (r = 0.879) was obtained for seed yield with seed oil percentage. Positive and significant correlations were measured for the number of seeds in pods with pod length (r = 0.699), pod area (r = 0.555), number of fertile pods (r = 0.678), and number of actual pods. Therefore, genotypes characterized by longer and more abundant pods play a crucial role in improving seed quantity, a key component of grain yield in saline environments. Consequently, the size and number of pods per plant serve as indicators of high-yield potential under such conditions. Based on the results of the principal component analysis (PCA), the first and second components had the highest relative variances, accounting for 44.66% and 31.22% of the total variance, respectively. Together, these two components accounted for 75.88% of the total variance. Factor loadings showed that traits such as number of fertile pods, seed yield, oil yield, and seed oil content had the highest factor loadings in the first component. Similarly, the plant growth rate had the highest factor load in the second component among all the studied traits. Cluster analysis divided the genotypes into four groups, and its dendrogram showed that all the studied genotypes were divided into four separate groups based on all the measured traits. The first group comprised three Karaj 1, 13, and 16 genotypes, the fourth group (like the first group) contained three Karaj 5, 11, and 15 genotypes, and the third group had five genotypes, namely Karaj 3, 7, 8, 10, and 14. The remaining genotypes were assigned to the second group.

The results of the present study demonstrate acceptable genetic diversity among rapeseed genotypes in terms of the evaluated traits in saline lands. This shows the importance and the possibility of using these genetic resources to achieve promising and superior genotypes in breeding programs.

Study of the promising plant Niger seed with the goal of oil production in Pakdasht

This research was carried out in the form of a split-split plot in the form of a randomized complete block design with three replications in the year 2021 in the Aburihan campus research farm located in Pakdasht. In this study, irrigation cycle in three levels (once every 7 days, once every 10 days and once every 13 days) as the main factor, planting date in two levels (5 June and 22 June) as a secondary factor and fertilizing with bio-fertilizers In four-level including control (without biofertilizer), Shift biofertilizer, Chris biofertilizer and the combination of Shift and Chris biofertilizers as sub-factors were considered.

The results showed that the plants cultivated on June 22 were superior to the plants cultivated on June 5 in all investigated traits (including yield components, seed yield, and biological yield) and all three tested irrigation levels. Also with increasing levels of drought stress, the seed yield has significantly decreased in both planting dates under investigation. However, the ratio of seed yield reduction under drought stress was significantly lower in plants cultivated on June 22nd compared to those cultivated on June 5th.

The cultivation of seed Niger plant with the application of Chris biofertilizer in the same weather conditions on June 22nd, is recommended as a promising plant that has an acceptable yield from an agricultural point of view and its product has a high oil content.

After being sprayed, nano-particles easily enter the leaves through the plant's stomatal system due to their small dimensions. Moreover, the significant increase in the molecular surface area of nano materials enhances their reactivity, consequently improving the plant's ability to utilize these compounds.

The present study was designed as a factorial experiment in a randomized complete block design (RCBD) at the research farm of the Central Station of the Agricultural Research and Education Center of Tehran Province. The study aimed to investigate the effects of foliar application in the form of seven treatments on the quantitative and qualitative performance and yield of the Goldasht safflower cultivar. The seven treatments included no spraying (control), spraying with normal and nano zinc, spraying with normal and nano iron, spraying with normal and nano manganese, and seed priming at three levels of non-priming (control), osmo-priming, and hydro-priming.

The results showed that osmo-priming, followed by spraying with nano zinc and then with nano iron, had the most significant effect on increasing all the investigated traits, including yield components, seed yield, and oil percentage in safflower. Additionally, hydro-priming with nano zinc spraying could increase the thousand-seed weight to the highest statistical level.

The study suggests that seed priming of safflower with foliar application of micronutrients, especially nano zinc, and iron, can be recommended as a promising method for enhancing the quantitative and qualitative performance and yield of safflower seed and oil in similar weather conditions.

Rapeseed is the second most important plant for oil production in the country due to having more than 40% of oil in the seed, resistance to some environmental stresses, and suitable combination of fatty acids. Water deficit in the stage of reproductive growth severely affects the rapeseed yield because the number of seeds and the weight of seeds decrease. Water shortage in the flowering stage also reduces the seed oil percentage and oil yield of rapeseed. In some areas of Khuzestan province, rapeseed is mainly cultivated as a beak crop. This issue causes the growth period of rapeseed to coincide with the growth of some other crops. In this situation, some irrigation turns are necessarily allocated to other plants (including wheat, which is in the pollination stage, and okra, which is in the germination stage), which causes rapeseed to face water shortage, even in the flowering stage. Therefore, it is necessary to apply appropriate management methods to reduce the effects of drought stress on rapeseed during the flowering stage. Among these methods is the use of vermicompost fertilizer and changing the planting date. The present study aimed to address the following inquiries: What impact does vermicompost fertilizer, planting date, and drought stress during the flowering stage have on rapeseed seed and oil production? Can the utilization of vermicompost fertilizer and adjustments to planting dates mitigate the adverse effects of water deficit stress on rapeseed yield?

A field experiment was conducted at the research farm of Shadegan Payam Noor University, Khuzestan, Iran in 2022-23 growing season. The experiment was carried out as a three-factor factorial 2x3x2 with three repetitions. The experimental factors included planting date (November 25 and December 25), vermicompost fertilizer (0.0, 10, and 20 ton ha-1), and irrigation (full irrigation and interruption of irrigation during the flowering stage). In each irrigation stage, the volume of irrigation water was measured and to calculate the efficiency of water consumption, the yield (seed and oil) was divided by the amount of evapotranspiration. At the maturity stage, the seed yield and its related traits included the number of pods per plant, the number of seeds per pod, the weight of 1000 seeds, biological yield, harvest index, oil and protein percentage of seed were calculated.

Rapeseed had the highest seed yield (2667 kg ha-1) on the planting date of November 25 with full irrigation, while delay in planting (planting date of November 25) and interruption of irrigation during the flowering stage resulted in the lowest seed yield (1247 kg ha-1) which means a decrease of more than 50% in seed yield. However, if rapeseed is planted on December 25 and fully irrigated, it has a higher seed yield (about 15%) than planting on November 25, along with stopping irrigation during the flowering stage. A similar trend was observed in seed oil percentage and oil yield, so the highest and lowest percentage and yield of rapeseed oil were obtained on the planting date of November 25 with full irrigation and the planting date of December 25 and stopping irrigation at the flowering stage, respectively. The delay in planting and drought stress in the flowering stage reduced the percentage of rapeseed oil by 6% and the yield of oil by about 60%. On the planting date of November 25, rapeseed was superior to the planting date of December 25 in terms of the number of seeds, 1000-seed weight, biological yield, and water efficiency by 35, 25, 23, 18, and 38%, respectively.

Vermicompost fertilizer helped to improve rapeseed seed yield by providing important nutrients. Stopping irrigation during the flowering stage and delaying planting caused a decrease in seed yield and rapeseed oil production. Therefore, to obtain the maximum yield of seed and oil, it is recommended to plant on the 25th of November and full irrigation. It is better to modify the planting pattern in the region to prevent the flowering stages of rapeseed from encountering water shortage.

In order to investigate the effect of ellagic acid on the growth indices and leaf aging process in soybean, an experiment was conducted during the two years of 2018 and 2019 in the research farm of Shahrood University of Technology's Faculty of Agriculture. The experiment was carried out factorial in the form of a randomized complete block design in three replications. The experimental treatments include the initial seed quality at two levels (normal seeds and aged seeds) and the application of ellagic acid at four levels (control, priming, foliar spraying and combined application of priming and foliar spraying with a concentration of 50 mg/L). The results showed that accelerated aging decreased the amount of chlorophyll, carotenoid, plant height, leaf and stem dry weight, oil percentage and seed yield compared to the control. The use of ellagic acid in the form of priming, foliar spraying and their combination in this study increased the percentage of oil by 0.23, 0.24 and 0.29%, respectively, compared to the control. Priming, foliar spraying and the combined application of priming and foliar spraying with ellagic acid improved the grain yield by 23.59, 23.23 and 55.48%, respectively. The use of ellagic acid as seed priming and foliar spraying better than other levels. Finally, it is recommended to use this material as a priming to increase the percentage of oil and yield of soybean.

In order to evaluate the grain yield and the quality characteristics of sunflower grain oil in response to deficit irrigation (DI), a split plot experiment based on randomized complete block design with three replications and two factors was carried out at experimental farm of Safiabad agricultural and natural resources research and education center in 2019–2020 growing seasons. The factors were DI as the main factor (including control, moderate DI, and severe DI- based on the discharge of 50, 70, and 90% of field capacity) and cultivar as sub-factor (including Oscar, Felix, Shakira, Savana, Labad, and Monaliza). The results showed that deficit irrigation caused a significant difference in grain yield, grain number per head, grain weight per head, oil quality characteristics compared to the control. Deficit irrigation caused a significant reduction in grain yield, grain number per head, and oil yield by 49.94, 49.94, and 26.67%, respectively, compared to control. In addition, deficit irrigation increased iodine index, peroxide value, phosphorus, chlorophyll content, carotenoid content, and oil acidity; hence, impurity in oil and oil corruption was increased. In conclusion, Felix and Labad cultivars are recommend for cultivation in Dezful and similar regions due to having high grain yield and maintaining yield under deficit irrigation conditions.

Climate change and global warming which are the consequences of rising temperatures, can affect agriculture in various ways. Heat stress is a serious threat to crop production in the world. Higher mean temperatures generally result in increased heat stress. This abiotic stress can adversely affect crop productivity and quality and weaken global food security. With current increased average temperatures, the occurrence of heat stress could become more intense. Terminal heat stress is the most widespread heat stress, limiting crop yields. Terminal heat stress during the reproductive stages will have a negative influence on grain yield and oil quality traits of oil seed crops. Sunflower is an annual oilseed crop with adaptation to dry land or irrigated cropping systems. It is suited to both spring and summer planting in most regions and it will be exposed to major climate change and potentially impacted by high mean temperatures. Therefore, climate change and heat stress is a major production constraint for sunflower worldwide and it may be severely damaged when exposed to stresses above its tolerance threshold.

In order to study of agronomic and physiological traits of sunflower cultivars under terminal heat stress, a field experiment was carried out during 2017-2018 growing season in Ahvaz conditions in a split plot arrangement in randomized complete blocks design with three replications. Main plots consisted of three sowing date including; 11th Nov, 11th Dec and 11th Jan, and sub plots consisted of five sunflower cultivars including; Qasem, Fantasia, Shams, Lakomka and Progress. Sowing date with desired temperature was considered as control, delayed and late sowing dates were considered as heat stress so that the flowering and grain filling periods of cultivars exposed to normal condition, moderate and severe terminal heat stress, respectively. Sunflower cultivars were evaluated under the optimum temperature (sown in the 11 November) and terminal heat stress condition (sown in 11 December and 11 January to expose the sunflower to higher temperatures than the optimum at the grain filling stage).

Terminal heat stress in delayed and late sowing date caused a decrease in biological yield, grain yield, number of seeds per head, 1000-seed weight, head weight, oil yield, chlorophyll index, relative water content, chlorophyll content and stomatal conductance. There was a significant difference between cultivars in terms of all traits. Lakomka and Progress had the highest values of grain and oil yield under control conditions, respectively. Late sowing date was led to a significant reduction in grain yield of Qasem, Fantasia, Progress, Lakomka and Shams cultivars by 69, 38, 6, 31 and 14%, respectively, compared to control. It was equal to 2.2, 1.2, 0.2, 1.1 and 0.4% for each day of sowing delay, respectively.

Lakomka cultivar showed higher oil yield in all three sowing date compared to other cultivars. In delayed sowing date, Progress cultivar showed higher oil yield due to higher grain yield and oil percentage. Due to the reduction of grain and oil yield in delayed sowing date, the perspective of sunflower cultivation in Khuzestan is probably related to its potential adaptation to climate change.

Sesame (Sesamum indicum. L) belongs to the Pedaliaceae family and is an annual and thermophilic plant known as the queen of oilseeds. Sesame is compatible with the climatic conditions of Iran, and due to its unique characteristics, it is possible to cultivate it second after wheat in arid and semi-arid regions. To utilize the maximum production capacity of sesame, implementing the proper agronomic practices such as plant density, optimal planting arrangement and selecting the appropriate genotype is inevitable.
 
To investigate the effect of planting arrangement and planting density on grain yield of two sesame genotypes, a factorial experiment based on a randomized complete block design with three replications was carried out in a hot and dry region situated in Behbahan (30° 36’ N; 50° 14’ E) in 2017 and 2018. The region is characterized as arid, and the average yearly precipitation (over a 30-yr period), which occurs mostly during the autumn and winter months, is 345 mm for the site. The annual mean temperature is 24 °C. The average temperature in 2017 was similar to the long-term meteorological data trend, while in 2017, the average temperature (22 °C) was lower. In this experiment, three factors included planting arrangement (cultivation of one and two rows on the ridge), planting density per unit area (including 20, 30 and 40 plants per square meter) and sesame genotypes Behbahan (local name) and Shavin cultivar were investigated. Data were subjected to ANOVA using SAS software (9.4 version). Because Bartlett’s test revealed homogeneity in the variance of all studied traits, data were presented as the mean values for both years. When an F-test showed statistical significance at, the protected LSD was used to separate the main effects, and the significant interaction effects were separated by the slicing method.
 
The results of grain yield, as the most important trait, indicated that in single-row cultivation, the maximum yield of the Behbahan genotype (1068 kg ha-1) was obtained at a density of 20 plants per square meter. An increase in planting density caused a significant reduction in grain yield when Behbahan genotype was sown as single-row arrangement. In two-row cultivation, the Behbahan genotype responded positively to an increase in plant density and an increase in planting density was associated with a significant increase in grain yield. However, the maximum grain yield obtained in two-row cultivation with a density of 40 plants per square meter (919 kg ha-1) was 16% lower compared to the superior treatment (single-row cultivation with a density of 20 plants per square meter). In the Shavin cultivar, the maximum grain yield was obtained in single-row (683 kg ha-1) and two-row (610 kg ha-1) arrangements at densities of 40 and 20 plants per square meter. The results showed that the average grain yield of the Behbahan genotype (851 kg ha-1) was significantly higher than the Shavin cultivar (561 kg ha-1).
 
Overall, in the Behbahan region and for the local genotype of Behbahan, as the superior genotype, a single-row arrangement and plant density of 20 plants per square meter is recommended.

Drought stress is one of the most important factors in reducing yield and seed quality of rapeseed. The present study chiefly tries to evaluate the effect of application of brassinosteroid on seed yield, oil content, oil yield, and fatty acids profile of rapeseed genotypes under late-season water deficit stresseen considered. A factorial split-plot test has been conducted in a randomized complete blocks design for two cultivation years (2017-2019) in Karaj, Iran. Experimental treatments include two levels of brassinosteroid (i.e., 0 (control) and 0.1μmol) and two levels of irrigation (full irrigation (control) and withholding irrigation from flowering stage) as factorial in the main plots, and rapeseed genotypes (Nafis, Ahmadi, Okapi, Nima, and Niloufar) as subplots. The levels of oleic acid and linoleic acid in the conditions of application of brassinosteroids have been 0.7% and 11% in full irrigation conditions and 1.1% and 6.4% in withholding irrigation conditions, respectively, compared to the control on the other hand, the use of brassinosteroids in withholding irrigation conditions reduce palmitic acid by 14% compared to the control. Okapi genotype has had the highest and lowest erucic acid and grain yield in irrigation conditions, respectively. Under drought stress conditions, the highest seed yield (3112.3 kg/ha) and the lowest amount of erucic acid (0.26%) belonged to Niloufar genotype. The use of brassinosteroids in both irrigation treatments improve the quality of fatty acids and Niloufar cultivar is recommended in both irrigation conditions

Combining organic and chemical fertilizers is one of the most important ways to achieve sustainable agriculture. In order to investigate the effect of organic fertilizers with chemical fertilizers on yield, yield components, and quality traits of sunflower, a factorial experiment was conducted in a randomized complete block design with three replications in spring 2018 at Gonbad Kavous University farm research. Cultivar factor included Haysan 25 and Oscar and combination of fertilizer factor included no fertilizer application, 100 kg N/ha, 50 kg N/ha, 50 kg N/ha + 1.5 kg humic acid/ha, 50 kg N/ha + 0.5 kg Vita free/ha, and 50 kg N/ha + 1.5 kg humic acid+ 0.5 kg Vita free/ha. The results showed that the effect of cultivar and fertilizer on most of the measured traits was significant. Oscar cultivar produced higher grain yield, biological yield and oil percent and oil yield than Haysan 25 cultivar. Grain yield, oil yield, biological yield and plant height in 100 kg N/ha treatment was higher than other fertilizer treatments though not significantly different from 50 kg N/ha + 1.5 kg humic acid/ha + 0.5 kg Vita free/ha treatment. Based on the results, in order to achieve the maximum seed and oil yield of sunflower and to prevent excessive use of chemical fertilizers, the combined use of Nitrogen fertilizer, humic acid and vita free is necessary.

In order to study the effect of brassinosteroids on yield and physiological characteristics of rapeseed genotypes under late-season drought stress, a factorial split-plot test is conducted in a randomized complete blocks design with three replicates for two cultivation years (2017-2019) in the research farm of Islamic Azad University, Karaj (Mahdasht). Experimental treatments include two levels of brassinosteroid (0 (the control) and 0.1 μmol) and two levels of irrigation (full irrigation (the control) and withholding irrigation from 50% flowering stage) as factorial in the main plots, with rapeseed genotypes (Nafis, Ahmadi, Okapi, Nima, and Niloofar) being considered as subplots. Foliar application of brassinosteroid under both full irrigation and withholding irrigation from the flowering stage increase seed yield, chlorophyll, and relative water content, compared to the control. The highest amount of soluble carbohydrates, leaf proline, and oil percentage have been obtained under drought stress and brassinosteroid application, i.e. 24.8%, 16.5%, and 2.5%, respectively, compared to the control conditions. However, Okapi genotype has had the highest stomatal resistance (24.59 s/cm), the lowest chlorophyll (1.49 μmolg-1FW), and seed yield (1960.5 kg/ha) in the conditions of withholding irrigation. Niloufar genotype has had the lowest stomatal resistance, the highest chlorophyll, oil percentage, and seed yield in both irrigation conditions. In general, in both irrigation treatments, the use of brassinosteroids improve physiological traits of rapeseed.

In order to study the changes of seed germination of soybean (Glycine max) and some biochemical characteristics, a factorial experiment as randomized complete block design was conducted at the Agricultural and Natural Resources Research Center of Ardabil Province (Maghan) in 2020-2021. Treatments included 2 spraying factors as iron and zinc sulfates besides three harvesting times: green pod, physiological maturity and dry mature pod. According to the results, interactions of spraying and harvesting time were significant on grain yield and protein percentage, and the highest amounts of both traits were obtained by applying zinc sulfate at dry mature pod. Seed oil content was affected by both treatments so that, the highest amount was obtained at the green pod at rate of 21.4% and zinc sulfate had the greatest effect on grain oil percentage at rate of 20.3%. Furthermore, interaction of spraying and harvesting time was significant on seed Fe and Zn contents and results showed that the highest amount of seed Fe (121.6 mg/kg) was achieved by iron sulfate and that of seed Zn (91.1 mg/kg) by zinc sulfate, both at the physiological maturity. Seed germination was also affected by interaction of spraying and harvesting time and the highest rate (96.6%) was observed at dry mature pod by applying zinc sulfate. In general, Zn consumption increased germination percentage, grain rate, seed oil percentage and grain yield, and iron consumption improved grain protein. The physiological maturity and dry mature pod harvestings improved the values of measured traits except the seed oil.

In order to study the effects of late-season drought stress and foliar application of zinc sulfate (ZnSO4) and manganese sulfate (MnSO4) on physiological characteristics and yield of rapeseed cultivars, a factorial split-plot test has been conducted in a randomized complete blocks design for two cultivation years (2017-2019) in Karaj, Iran. The experimental treatments include two levels of irrigation (full irrigation (control) and withholding irrigation from flowering stage) and four levels of foliar application (control, ZnSO4, and MnSO4, separately, as well as their combined application) as factorial in the main plots, with rapeseed genotypes (Nima, Niloofar, and KS7) considered as subplots. Combined foliar application of zinc and manganese sulfate under full irrigation conditions increase the content of seed oil and soluble carbohydrates by 3% and 11%, respectively, compared to the control. On the other hand, withholding irrigation from flowering stage increases the percentage of seed oil and leaf proline content, compared to the control by 9% and 5.2%, respectively. Niloofar genotype has had the highest seed yield (5261 kg/ha) under full irrigation conditions, i.e. 9% and 11.8% higher than KS7 and Nima genotypes, respectively. Nima genotype with 3371 kg/ha has had the highest yield in the conditions of withholding irrigation. In general, in both irrigation treatments, simultaneous foliar application of zinc sulfate and manganese has had the greatest impact on the physiological traits of the studied genotypes, thus Niloofar genotype is recommended for full irrigation and Nima genotype for interrupted irrigation.

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.

In order to investigate the effect of tillage systems and the combination of chemical fertilizer and livestock manure on some characteristics of sunflower, an experiment has been conducted as split plots in a randomized complete block design with three replications at the research farm of University of Zabol during 2019. The main factor has been tillage levels (1. moldboard plow and disc, 2. sweep and disc, and 3. disc). The sub-factor include fertilizer levels (no fertilizer application, 100 kg/ha of diammonium phosphate, 25 tons/ha of livestock manure+ 100 kg/ha of diamonium phosphate, 50 tons/ha of livestock manure + 100 kg/ha of diamonium phosphate, 25 tons/ha of livestock manure, and 50 tons/ha of livestock manure). Results show that the highest values belong to the 50 tons/ha of livestock manure in tillage with disk for grain yield (5072 kg/ha), and oil percentage (44.44%), 50 tons/ha of livestock manure in tillage with disc for oleic acid content (51.61%), and 50 tons/ha of livestock manure for linoleic acid content (31.1%). The highest amount of chlorophyll a, b and carotenoids (1.253, 0.45, and 1.04 mg/g, respectively) has been obtained from the application of 100 kg/ha of diamonium phosphate in tillage with disc. In general, in order to increase and improve the quantitative and qualitative characteristics of sunflower, the application of 50 tons/ha of livestock manure is suitable in disc tillage conditions.

Sunflower (Helianthus annus L.) is one of the five important oil plants of Iran. Water deficit stress is one of the most important limiting factors in sunflower cultivation. Methanol is used to deal with environmental stresses, especially dehydration. Preventing or reducing light respiration, delaying leaf senescence, increasing photosynthetic activation period and leaf area duration index and increasing Co2 fixation are among the roles of methanol application in plants. Therefore, this study was conducted to investigate the effect of methanol spraying on some morphophysiological characteristics, yield and yield components of sunflower under drought stress conditions.

This field experiment was conducted as a split plot based on randomized complete block design with three replications in Birjand, Iran, in 2017. The main plots included two levels irrigation (irrigation after 80 and 160 mm evaporation form class A pan). On the other hand, the sub- plots included five levels of methanol spraying; control (no spraying), 7, 14 and 21 v/v. Statistical analysis was performed using MSTATC software. Duncan's multiple range test at the 5% level of probability was used to compare the means.ResultsResults showed that deficit irrigation reduced stem diameter, number of seeds per head and kernel / husk weight ratio. Methanol spraying also increased the number of seeds per head. Also, methanol spraying improved most of the studied traits under two irrigation treatments. So that under drought stress conditions, foliar application with 28% volumetric methanol increased plant height (9.9%), stem diameter (5%) and leaf number per plant (14.7%). Compared to control, foliar application with 14% volumetric methanol increased chlorophyll content (8%) and foliar application with 21% volume methanol increased stomatal conductance (34.7%), 1000-grain weight (12%), grain yield (27.9%) and biological yield (23.4%). According to the results, under optimum irrigation conditions, maximum sunflower grain yield was obtained with 28% volumetric methanol spraying, but under drought stress conditions, spraying with 21% volume methanol was the best one.

The results showed that foliar application of methanol under optimum and also deficit irrigation conditions did not affect the percentage and yield of sunflower oil seed, but increased seed yield. Maximum grain yield under optimum irrigation was obtained with 28% volumetric spraying, which was 27% more than control. Also, the results showed that under arid and semi-arid conditions of Birjand, deficit irrigation with using methanol (21% volumetric) produces acceptable grain yield.Chlorophyll meter, Leaf temperature, Oil percentage, Stomatal conductance

Rapeseed (Brassica napus L.) has a special rank among oilseeds due to its outstanding agronomic characteristics. Planting date is an important factor that affects grain yield, oil content and fatty acid composition. Delay in rapeseed planting reduces vegetative growth period and produces plants with less biomass, and reduces yield components and grain yield due to the exposure of the reproductive stage to high temperatures. Proper nutrition of the plant is one of the important factors in improving the quantity and quality of the product. Silicon is not considered an essential element for excellent plants. However, silicon has an effect on improving plant growth, biomass, seed yield and quality, photosynthesis and resistance to biotic and abiotic stresses. Zinc also regulates plant growth and activates many enzymes. This element is necessary for the synthesis of chlorophyll and the formation of carbohydrates.

In order to conduct this research, a field experiment was conducted as a split-factorial in a randomized complete block design with three replications at Qhaemshahr Agricultural Research Station (Qarakheil) during 2017-18. Planting dates as the main plot at two levels (normal planting [7 October] and delayed planting [22 October]), silicon fertilizer sources at three levels (control [no consumption], calcium silicate, nano-Si) and zinc fertilizer sources at three levels (control [no consumption], zinc sulfate, nano-Zn) were considered as sub-plots. Calcium silicate and zinc sulfate (200 kg ha-1) were added to the soil before rapeseed planting. Silica and zinc nanoparticles (50 mg l-1) were sprayed in two stages of flowering and pod formation. The soil of the test site had clay loamy texture with pH 7.5, organic matter 3.2%, total nitrogen 0.16%, absorbable P 15.7 mg kg-1 and absorbable K 101 mg kg-1. The average annual rainfall at the test site was 745 mm. Data were analyzed by Mstat-C statistical software and the means were compared with LSD test at a probability level of 5%.

Plant height, number of pods per plant, number of seeds per pod, 1000-seed weight, grain yield, seed oil, grain silica and grain zinc were the studied traits that other than grain silica (non-significant) other traits decreased with delay in planting. The present study showed that for each day of delay in planting, 39.15 kg ha-1 of grain yield was reduced. With the delay of planting from 7 October to 22 October, the total grain yield decreased by 22.03% due to the decrease in the number of pods per plant, 1000-seed weight and number of seeds per pod. Seed oil also decreased by 3.3% with a delay in planting. Number of pods per plant (10.30 and 12.11%), grain yield (11.15 and 12.43%), and grain silica (9.63 and 11.57%) increased with the use of calcium silicate and nano-silica, respectively, compared to the control. The number of seeds in pods (14.85 and 13.01%) and grain zinc (21.47 and 26.57%) also increased with the use of zinc sulfate and nano-zinc, respectively, compared to the control. Nano-zinc increased the number of pods per plant, 1000-seed weight and grain yield compared to the control (18.66, 15.64 and 20.50%, respectively). The maximum number of seeds per pod was obtained in normal planting date with calcium silicate (49.8 seeds) and the maximum seed oil was obtained under the combined treatments of nano-silica and zinc sulfate (47.3%) and nano-silica and nano-zinc (47.5%).

In general, the results of the current study showed that the highest grain yield and grain silica concentration were obtained by application different sources of silica as well as nano-zinc foliar application. The maximum concentration of grain zinc was obtained by application different sources of zinc. The highest percentage of oil was recorded with the simultaneous application of nano-silica and different sources of zinc.

Sunflower is a semi-drought tolerant plant that due to its importance in oil production, the area under cultivation is expanding. But drought stress severely reduces the yield of grain and oil. Therefore, the production and introduction of hybrid cultivars can help increase performance. The first step in the production of hybrid is to identify parents based on their General and Specific combining ability and also to determine the type gene actions.

In order to investigate the combining ability of sunflowers inbred lines under normal conditions and drought stress, a study using 12 sunflower hybrids obtained from the cross of male sterile and tester lines with two controls, Qasem and Shams, in two separate experiments in the form of The design of randomized complete blocks with three replications was performed under two conditions of normal irrigation and drought stress.

The results of combined analysis of variance of the studied treatments under both normal and drought stress conditions showed that drought stress had a significant effect on all studied traits number of seeds per head. The effect of lines for plant height, oil percentage and head diameter and the effect of testers were significant for most traits except number of seeds per head, which shows a significant difference between the general combinability of lines and testers. Also, line 1 and tester 3 in both normal and stress conditions with a negative and significant combinability for the height of the parent plant is suitable to reduce this trait in the cross. In addition, line × tester interaction had a significant effect on most traits except 1000-seed weight and number of seeds. The Line 1 and Tester 1 with significant positive general combining ability (GCA) effects for grain yields were considered as suitable combiners for improving these traits. So that under normal conditions, hybrid No. 13 with grain yield of 5224 kg / ha had the highest grain yield and under stress conditions of hybrid No. 31 with an average of 3544.6 kg / ha had the highest grain yield.

The general results of this study show that the important traits of grain yield, oil percentage and oil yield are controlled by the dominance gene action, which can be improved by hybridization and best selection of parents in breeding programs.

The aim of this study was to investigate the effect of foliar application of polyamine compounds on seed and oil yields and fatty acids production in safflower under deficit irrigation stress. A split plot experiment based on randomized complete block design with four replications was conducted in the research farm of College of Agriculture, Shahed University in 2016-2017. Treatments were irrigation at two levels (normal irrigation and deficit irrigation (irrigation after 50 and 75% depletion of field capacity, respectively) as the main factor and foliar application of polyamine compounds at 10 levels (foliar application with water as control and foliar application with putrescine, spermidin and spermin at 0.05, 0.1 and 0.2 mM concentrations) as secondary factor. At each irrigation level, the putrescine foliar application significantly increased seed and oil yields, harvest index, water use efficiency and oleic acid. Increased levels of putrescine and spermin foliar application ranged from 0.05 to 0.2 mM under deficit irrigation stress conditions resulted in 40.4% and 38.3%, increase in the biological yield respectively, compared to control. Also, foliar application of the highest concentration of spermin (i.e. 0.2 mM) under water deficit stress significantly increased total yield of unsaturated fatty acids and reduced the percentage of palmitic acid. Spermidine foliar application significantly increased linoleic acid yield in safflower oil under water deficit conditions. It can be concluded that foliar application of polyamine compounds can increase seed and oil yields and water use efficiency and improve the quality of safflower oil in deficit irrigation conditions.