جستجوی مقالات مرتبط با کلیدواژه « درصد روغن » 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.

Aram is a new oilseed rape cultivar, extracted from the R308 (earlness line) and RGS003 (high-yield cultivar) cross population through pedigree method in three years. To reach high-yielding and compatible lines and cultivars, preliminary and advanced investigations were carried out in Gorgan and Sari (2014-2015) and Zabol, Gorgan, Sari and Borazjan (2016-2017). The line SRL-93-12 (Aram cultivar) with a yield of 2955 kgha-1 and 2774 kgha-1 was the first in the above-mentioned tests, respectively, and the SRL-93-12 line was also recognized as the most stable genotype based on the lowest Lins and Binns superiority index and highest seed yield. Extension research project results on farmers' farms in Behbahan, Moghan, and Gorgan regions showed that the new line with 594 kgha-1 higher yield than the check cultivar was in the first rank. According to the results as well as desirable agronomic traits such as good tolerance to dormancy and uniformity in maturity, this line was released with the name Aram.

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.

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.

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.

In order to investigate the effect of planting densities and different amounts of nitrogen on leaf greenness index and leaf area index, seed yield and oil yield, irrigation water productivity and nitrogen use efficiency in sunflower, an experiment was conducted as a split plot in the form of randomized complete blocks design with three replications in the research farm of Agriculture Institute in Semnan province in the spring of 2019. Plant density in four levels (4, 6, 8 and 10 plants per m2) as a main plot and the amount of nitrogen levels (0. 50, 100, 150 and 200 kg urea ha-1) as sub plot was considered. Leaf greenness index, plant height, 100-seed weight, seed nitrogen content and seed oil content were significantly affected by the simple effect of planting density, which decreased with increasing density of the above traits. Also, the nitrogen levels significantly affected the studied traits, so that with increasing the amount of nitrogen consumption, from control (0 kg urea ha-1) to 200 kg urea ha-1, the leaf greenness index increased by 15.3%. The highest amount of plant height, 100-seed weight and grain nitrogen were obtained in the treatment of 150 kg urea ha-1 and 14.13, 9.07 and 24.3% more than no application, respectively. Mean comparing the results of water use efficiency showed that at a density of four plants per m2 and an increase in nitrogen levels, along with increasing height and leaf area index, water use efficiency also increased, but higher levels of density led to smaller plant yield, less plant biomass and water efficiency were reduced. The highest nitrogen use efficiency was obtained in the density of 8 plants per m2 and no application of nitrogen fertilizer. Finally, maximum grain yield (4016 kg.ha-1) and oil yield (1827 kg.ha-1) were obtained by consuming 150 kg urea per ha-1 and density of 8 plants per m2.

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.

The south warm climate of Iran is one of the regions with the ability to grow spring oilseed rape cultivars. Cultivation of oilseed rape in this climate faces the problem of environmental stress such as terminal drought and heat stress. Therefore, in addition to yield, earliness is one of the important priorities to introducing spring oilseed rape cultivars in these areas. Asa (promising line SRL-93-4) is an early-maturing and relatively high-yielding cultivar that resulted from hybridization between R308 early-maturing spring line and Modena as a high-yielding winter cultivar. The segregated generations were conducted by pedigree method. Preliminary and adaptation trails showed that SRL-93-4 line was superior compared to check cultivars in the regions under study. In the adaptation trail, the SRL-93-4 line (with 2581 kgha-1 seed yield) showed a significant superiority over the control cultivar RGS003 (with 2155 kgha-1 seed yield). Also, it was found that the SRL-93-4 line was matured 11 days earlier than the check variety RGS003 on the average. The results of stability methods revealed that SRL-93-4 line was the high stable genotype. A field trial for Blackleg disease showed that the SRL-93-4 line had a relative tolerance to the Blackleg. Analysis of the fatty acids profile showed that SRL-93-4 seed oil had a level of erucic acid close to zero, and in terms of the composition of fatty acids, it was within the standard range, but with more oleic acid and less linolenic acid compared to the RGS003 variety. Also, the amount of glucosinolate of the meal was less than standard level. The results of the on-farm trails in Zahak and Zabol regions of the Sistan and Baluchestan province showed that SRL-93-4 line (with 2200 kgha-1 seed yield) had a non-significant difference seed yield with Dalgan check cultivar (with 2361 kgha-1 seed yield); But it was eight days earlier than the check variety. Therefore, due to the desirable characteristics such as early maturity, relative tolerance to Blackleg disease and good performance, the new promising line SRL-93-4 which released as Asa variety is recommended for cultivation in the south warm regions of the country.

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.

The castor bean (Ricinus communis L.), is an oilseed of relevant economic and social importance. From its seeds is extracted an oil of excellent properties, having wide use as industrial input and several applications. It is cultivated since the times of the ancient civilizations, the castor bean is a rustic plant, resistant to drought, belonging to the family of Euphorbiaceae, Drought stress, in addition to the negative effect on yield, causes or exacerbates other stresses, especially the stress of nutrient deficiencies for the plant. The purpose of this investigation was study effect of irrigation levels and Superabsorbents and biofertilizers on the agronomic properties of castor oil.

This experiment was conducted in West Azarbaijan Agricultural Research and Education Center, Orumieh- Iran at 2018-2021 crop season. Field experiment was carried out by a split plot design based on completely randomized block design with three replications. The first factor included Four levels (70, 100, 130 and 160 mm of evaporation pan),in the main plot and Sub-factor includes application of biofertilizer combination in four levels (Azospirillium, Citrobacter, combination of application of Azospirillium in Citrobacter and control without fertilizer) and superabsorbent in two levels (superabsorbent consumption and non-superabsorbent consumption) as factorial were placed in sub-plots. In this study, plant height, main length cluster, capsules number per plant, seeds number per plant, thousand kernel weight, biological yield, grain yield harvest index, oil percent and oil yield were measured. Also Traits were analyzed by using SAS 9.2 software and means comparison was tested by least significant difference (LSD).

The results of analysis of variance showed the effect of irrigation, biofertilizer and superabsorbent treatments at the level of 1% probability on plant height, number of seeds per plant, main cluster length, number of capsules per plant, 1000-seed weight, biological yield, grain yield, harvest index Oil percentage, oil yield, castor oil were significant. Also, the interaction effect of biosorbent and superabsorbent on plant height, number of seeds per plant, main cluster length and oil yield at the level of 5% probability and on grain yield, harvest index at the level of 1% probability was significant. The results showed that irrigation treatment after 160 mm of evaporation pan reduced plant height, number of seeds per plant, length of main cluster, number of capsules per plant, 1000-kernal weight, biological yield, grain yield, harvest index, oil percentage and oil yield in comparison with irrigation treatment after 70 mm by 7.62, 5.26, 12.19, 5.25, 5.86, 3.38, 9.50, 6.10, 2.38 and 11.83 percent, respectively. Among the biofertilizer treatments, seed inoculation with Citrobacter was able to increase the number of capsules, 1000-seed weight, biological yield and oil percentage compared to the control treatment by 5.5, 17.28, 2.74 and 8.50%, respectively. Among the interaction treatments, the highest plant height (165.21 cm), main cluster length (23.55 cm), grain yield (1137.61 kg ha-1), harvest index (20.72%) and oil yield (597.91 kg ha-1) was allocated to superabsorbent treatment and inoculation with Citrobacter.

In this study, by exacerbation of water stress, all agronomic traits were reduced. It can be concluded that water deficit stress reduces the amount of photo assimilate and transfer of these substances by disrupting the photosynthesis process, and thus grain yield and yield components as well as oil percentage and oil yield are affected, Therefore, in order to achieve maximum economic yield in castor, irrigation should be done with a regular plan and the plant should not face long periods of drought as much as possible. In this study, the use of biological fertilizers, especially citrobacter, both individually and in combination with supergene had a positive effect on increasing grain yield and grain yield components, oil content and oil yield. Therefore, the use of these materials to improve the economic performance of castor oil is recommended.

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.

A field experiment was carried out at the research field of Payame Noor university of Shadegan, Khuzestan province during 2021-2022 growing season to evaluate the grain and oil production of sesame under deficit irrigation in response to vermicompost application. The experiment was conducted as split-plot in three replications, where irrigation treatments (I1: full root zone irrigation and I2: partial root zone irrigation) were allocated to main plots and vermicompost (0.0, 5.0, 10.0, 15.0 and 20.0 t ha-1) were assigned as sub plots. Results indicated that oil percentage, grain and oil yield of sesame were reduced 3.0%, 17.7% and 23.9% under partial root zone irrigation, respectively. Significant reduction (P≤0.01) of grain number and grain weight under partial root zone irrigation (30% and 11.2%, respectively) showed that grain yield of sesame was affected by both components of grain yield. However, grain number was more sensitive to water shortage compared with grain weight. Water consumption in the limited irrigation treatment was reduced by 49.2%, and this caused the water productivity for seed and oil production to increase by 61.7% and 49%, respectively, compared to the full irrigation of the root system. The use of vermicompost fertilizer led to the improvement of sesame grain and oil yield and their related traits, so that with the consumption of 20 t ha-1 of fertilizer, the grain and oil yield increased from 791 to 1248 kg ha-1 (57.8% increase) and 374 to 657 kg ha-1 (75.7% increase), respectively. Therefore, the use of vermicompost fertilizer can help to improve the yield of sesame seeds and oil under limited irrigation conditions.

Study of adaptability and performance are important steps in the introduction of new olive cultivars for target regions. In this research, pomological characteristics, fruit and oil yield of 55 foreign and native olive cultivars were evaluated at Tarom olive research station from 2015 to 2017. The results showed that the effect of year, cultivar and their interaction effect on fruit yield were significant (P≤ 0.01). Cv. Toffahi with an average fruit weight of 11.36 grams had the largest fruit followed by cv. Jlot, cv. Chalkidiki and cv. Voliotiki with average fruit weight of more than 10 grams. Cv. Jlot had the highest fruit flesh (93%) and cv. Khodeiri had the highest (69.53%) dry matter oil content. Cv. Chalkidiki, cv. Nebali, cv. Arbequina, cv. Agromanaki, cv. Megaron, cv. Koroneiki with 66.28-55.67 percent dry matter oil content were among the cultivars with high oil content. The highest fruit yield per tree (80.16 kg tree-1) obtained from cv. Caridolia. Cv. Abusatl, cv. Moussaabi, cv. Arbequina, cv. Koroneiki, cv. Caridolia and cv. Conservolia were also high yielding with high yield stability cultivars, respectively. The highest oil yield belonged to cv. Caridolia, cv. Koroneiki and cv. Conservolia with 2974, 3412 and 2782 kg ha-1, respectively. Cv. Picual, cv. Chalkidiki and cv. Abusatl also produced more than two tons of oil per hectare.

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.

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.

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

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 investigate the effect of humic acid on some of physiological characteristics and agronomic traits of rapeseed (Brassica napus L.) cultivars under drought stress conditions, the present experiment was carried out as Split-split plot design randomized complete blocks design with 4 replications in Kaleybar city in 2019. The main plot, sub plot and Sub-sub plot included irrigation after 60, 90 and 120 mm water evaporation from class A evaporation pan, bean cultivars divided into 4 categories of Hayola 420, Sarigol, Traper and RJS003, and humic acid application on 5 levels (0, 100, 200, 300 and 400 mg.Lit), respectively. The results showed that the simple effects of drought stress, humic acid and cultivars traits measured at a probability level of 1%. The interaction between water stress and humic acid on chlorophyll content, plant height, number of pods per plant, grain yield and oil yield were significant. The effect of dual interaction (drought stress × humic acid and drought stress × cultivars) on chlorophyll index, plant height, number of pods per plant, grain yield and oil yield were significant. With increasing drought stress, the relative moisture content (20.54%), number of grains per pod (25.32%), 1000-grain weight (16.58%) and oil content (6.75%) decreased; While increasing the proline concentration (35.13%). The highest oil yield and grain yield were allocated to 60 mm of evaporation and 400 mg/l of humic acid and the lowest amount of oil and grain yield was assigned to 120 mm of evaporation and no use of humic acid. Humic acid increased the relative moisture content, number of seeds per pod, 1000-seed weight and oil percentage and decreased the amount of proline (26.31%). As a result, spraying 400 mg/l humic acid at different levels of drought stress improved physiological characteristics and increased production components compared to the control (no spraying). In the four cultivars evaluated, Hayola 420 cultivar had the highest grain yield and yield components. According to the results, humic acid reduces damages caused by drought stress.

Severe climate changes and rapid population growth have influenced global food security. Oilseeds are the second main source of human food after cereals. Increases in the demand for vegetable oil at global markets and thus increases in the price of these oils, an economic pressure has been imposed on the oil-importing countries. So, concerning population growth and increases in per capita food consumption, it is necessary to increase the area under oilseeds' cultivation and crop yield. Safflower is an oilseed crop of the family Asteraceae with favorable and unique characteristics that make it a valuable oilseed crop. Safflower due to having long roots and the high ability for absorbing water from deep soil layers, is considered as a low water-tolerant plant; but after the rosette stage, it becomes more sensitive to water stress such that since the first signs of inflorescence emergence up to the middle of the grain-filling period, it shows more sensitivity to this kind of stress.

This study was performed during the 2018-2019 cultivation year in a 400-ha farm located in the Seed and Plant Improvement Institute, Karaj, Iran. The geographical location of the study area is 35° 49' N, 51° 6' E, and its elevation is 1321 m AMSL. According to climate data and ambrothermic curve, this area, due to having 150- 180 dry days, is considered as hot and dry Mediterranean climate. Because of having cold and humid winters but hot and dry summers, it has a dry moisture regime. Based on the average of 30-years of climate data, the mean temperature is 13.5 °C, the soil temperature is 14.5 °C, and in terms of soil temperature regime classification, it is considered as thermic areas. Table 1 represents the mean monthly temperature and precipitation during 2018-2019 and 2019-2020 cultivation years in Karaj. The main factor of this experiment was drought stress in two levels, i.e. normal irrigation (control) and irrigation cut-off at flowering stage, and two sub-factors include safflower cultivars (Golmehr and Goldasht) and foliar application of auxin in two levels, i.e. zero-application and applying 4 gL-1 auxin.

Results of the present study illustrated that compared with Golmehr cultivar, Goldasht had higher number of grains per head, grain yield and biological yield. On the other hand, Golmehr cultivar had a higher plant height, percentages of oil, linolenic acid, and oleic acid, compared to Goldasht cultivar. Under drought stress, the activities of antioxidant enzymes and proline were not significantly different between the two cultivars; however, the Goldasht cultivar by accumulating the activities of catalase, peroxidase enzymes, and proline content showed higher resistance to drought condition than the Golmehr cultivar. Irrigation cut-off at flowering stage led to decreases in bush height, number of grains per head, number of plant heads, 1000-grain weight, grain yield, biological yield, harvest index, SPAD index, percentages of oil, palmitic acid, linoleic acid, oleic acid and increases in proline content, activities of antioxidant enzymes, i.e., catalase and peroxidase. In comparison with the no-auxin situation, applying auxin increased SPAD index, proline content and, activities of catalase and peroxidase so, it could alleviate the side effects of drought stress. Therefore, in addition to the reduction of production costs and saving water, especially in arid and semi-arid areas, which results from the foliar application of auxin and cutting of irrigation at flowering stage, also crop yield and oil percentage could be gained same as the ones gained under normal condition. Furthermore, concerning the evaluated characteristics and the reaction of studied cultivars to drought, Goldasht cultivar can be introduced as the preferable cultivar under drought stress conditions.