مجله به زراعی کشاورزی
سال بیست و چهارم شماره 4 (زمستان 1401)

A field experiment has been carried out to study the competition between soybean and sesame in different planting ratios of intercropping based on replacement method. It is based on a randomized complete block design with four replications at Sari Agricultural Science and Natural Resources University during 2019. The planting ratios are 0:100, 25:75, 50:50, 75:25, and 100:0 (Soybean: Sesame respectively), using replacement method. Results show that intercropping has had a significant effect on the percentage of N derived from the atmosphere and light use efficiency. Among the different planting ratios, the maximum amount of biological nitrogen fixation is related to the 90-days after planting, and the 75:25 and 25:75 planting ratios have had the highest (75.95%) and lowest activity rates (42.67%), respectively. In addition, the highest light use efficiency in intercropping is related to the 120-days after planting. At this stage, the light use efficiency in 75:25 and 50:50 ratios are 2.03 and 1.92 g.MJ.-1, respectively. The highest land equivalent ratio is 50:50, with an average of 1.12. Finally, increasing the light use efficiency in planting ratios of 75:25 and 50:50 prove to be essential in increasing soybean's biological nitrogen fixation and increasing the efficiency of intercropping cultivation.

In order to evaluate the ability of forage sorghum (Sorghum bicolor L.) to remediate the heavy metal cadmium with biochar and Pseudomonas putida, a factorial experiment has been conducted based on completely randomized design accomplished in greenhouse conditions with four replications at Sari Agricultural Sciences and Natural Resources University, in the summer of 2019. Results show that the presence of cadmium in the medium of sorghum reduce the dry weight of root and shoot. However, adding biochar and bacterial inoculation significantly increase the mentioned traits. Bioconcentration factor and bioaccumulation factor have increased from 25 to 100 mg of cadmium, when the highest shoot bioaccumulation factor (2.31) is observed at a concentration of 100 mg Cd per kg soil and in the simultaneous application of Biochar and Pseudomonas putida, which is a significant increase of 28.33% compared to the control. The lowest translocation factor of sorghum (1.000) is related to non-application of biochar, non-inoculation of Pseudomonas putida and without cadmium contamination, itslef reduced by 20% compared to the control, while the highest translocation factor (1.94) is observed at a concentration of 25 mg of cadmium per kg of soil and treatment of non-application of biochar and non-inoculation of Pseudomonas putida. Plant tolerance index has decreased by increasing cadmium concentration, while the use of biochar and inoculation of Pseudomonas putida has increased this index when the highest tolerance index (1.22) is related to the treatment of combined use of biochar and bacteria with no cadmium, increased by 22% compared to non-application of biochar and non-inoculation bacteria. As the tolerance index of forage sorghum in all concentrations of cadmium is more than 0.60, this plant can be classified in the highly-tolerant group to the heavy metal cadmium stress and sorghum could be used for cadmium phytoremediation.

Water plays a very important role in the rice plant. In order to investigate the effects of irrigation methods and foliar application of nutrients on growth, yield, yield components, and quality of rice, an experiment has been conducted as split plots layouts based on a randomized complete block design with three replications and two factors including three irrigation methods (flooding, alternate wetting, drying, and Saturating) in the main plots as well as foliar spray in six levels (normal water, nitrogen, nitrogen+ potassium, nitrogen+ potassium+ zinc, nitrogen+ potassium+ zinc+ boron and nitrogen+ potassium+ zinc+ boron+ molybdenum) in the sub plots during 2018, in rice research institute, the deputy of Mazandaran (Amol), executed on a national cultivar. Results show that among irrigation method, fertilizer, and their interaction, paddy yield and percentage of amylose have been significantly at (p<0.01) percent with other qualitative traits being significant at (p<0.01) percent. The highest number of floret per panicle (198.73) and full grain (167.15), and percentage of amylose (21.67%) are obtained in saturated irrigation. The highest yield of paddy with an average of 6643.07 kg.ha-1 occurs in saturated irrigation under normal water foliar application and drought and moisture. Irrigation under nitrogen + potassium + zinc foliar irrigation with an average of 6163.13 kg.ha-1 compared to the control is obtained as the superior treatment in similar conditions were selected for this study.

Drought is one of the most important factors limiting corn production in the world. On the other hand, the use of renewable resources and inputs such as vermicompost is one of the principles of sustainable agriculture. Therefore, in order to investigate the effect of deficit irrigation, chemical fertilizers and vermicompost an experiment has been performed in the form of split split plots in a randomized complete block design with 3 replications for two years (2017 and 2018) in Kermanshah Agricultural Research and Training Center. Irrigation treatment include optimum, 80% and 60% of water requirement. Chemical fertilizer include 100% and 50% recommended and vermicompost include 0, 2, 4,and 6 ton ha-1 arranged as main plots, sub plots, and sub sub plots, respectively. Results show that leaf area index is decreased from 4.51 to 1.6 from normal irrigation to intense drought stress. The highest yield of fresh forage (82.5 ton ha-1) is obtained in optimal irrigation treatment and combined use of 100% chemical fertilizer and 6 ton ha-1 of vermicompost and the lowest rate (30.1 ton ha-1) is related to 60% water requirement and no use of vermicompost chemical fertilizers. At all irrigation tratments, the percentages of forage protein increase with the use of fertilizers and vermicompost, and the highest percentage of forage protein (10.2%) is obtained in complete irrigation treatment and 100% fertilizer application and 6 ton ha-1 vermicompost. Based on the results in irrigation treatment by 60% of water requirement and application of 50% of chemical fertilizer, application of vermicompost at the rate of six tons per hectare, compared to no application, increases fresh forage by 26.26% and protein by 6.9%.

In order to determine the phenological differences of some improved rice cultivars in Iran for applying in crop simulation models, an experiment has been conducted in the research farm of the Rice Research Institute of Iran (Rasht) in 2020 as a randomized complete block with three replications. The experimental treatment consist of six rice cultivars (Rash, Anam, Gohar, SA1, SA6 and M7). Results show that the highest development rate can be observed in development rate in juvenile phase and grain filling phase in Anam cultivar. The minimum and maximum time required to start emergence with 3 and 6 days are in Anam and Gohar cultivars, respectively. The maximum time required to achieve maximum flowering and physiological maturity is obtained with 71 and 103 days in Gohar cultivar. The highest flowering period with 19 and 20 days is obtained in late maturing Rash and Gohar cultivars, respectively. The highest growth degree days (GDD) in beginning of grain filling to maturity stage is observed with 401 GDD for M7 cultivar. The highest growth-day for pre-flowering with 1208 GDD belongs to Gohar cultivar. The highest harvest index is obtained with 50.91% in Gohar cultivar. The results also show that the single grain weight under ideal growing conditions with 0.030 g is observed in Gohar and M7 cultivars. The highest plant height belongs to cultivar M7 with 150 cm and the highest total nitrogen uptake is observed in the plant at maturity of Anam cultivar. Overall, the estimated genetic coefficients in different models differ between cultivars and the coefficients vary in the range defined in the model for different groups of maturity. To accurately calculate the genetic coefficients, it is suggested that this experiment should be repeated over several years and in different ecosystems under rice cultivation.

Nowadays, the use of stress modulators as a useful and low-cost solution to reduce the effects of environmental stress has been considered by researchers. In order to investigate the effects of stress modulator’s foliar application in different planting dates on yield and yield components of cotton, an experiment has been conducted as split-plot factorial in a randomized complete block design with three replications in Sabzevar Islamic Azad University in 2017 and 2018. Factors include planting date (early and late) as the main plot and type of stress modulator (control, salicylic acid (SA) 2 and 4 mM, glycine betaine (GB) 50 and 100 mM and sodium nitroprusside (SNP) 100 and 200 μM) as the sub-plots. Foliar application of 2 mM SA in the first year and 4mM SA in the second year produce the highest number of bolls per plant (10.1 and 7.58, respectively). In contrast, 4 mM SA spraying in early planting date increases seed cotton yield (45.6%), but in late planting date, seed cotton yield does not respond to the stress modulator application. In the first year, 100 μM SNP foliar application has the highest lint yield in both early and late planting dates, but in the second year, 2 mM SA foliar application produce higher lint yields. Overall, the results of this experiment show that the highest yield of cotton in saline conditions are obtained in sowing at the appropriate date and foliar application of 4 mM salicylic acid.

The present study has been conducted to compare new sugar beet cultivars for quantitative and qualitative traits in autumn sown condition as randomized complete block design at Safiabad agricultural and natural resources research and education center in 2017-2018. It has included 22 new sugar beet cultivar, investigated in three replications. Measured traits included number of leaf in plant, root yield, sugar content, white sugar content, white sugar yield, extraction coefficient of sugar, sodium, potassium, α-amino nitrogen, molasses sugar, and alkaloid ratio. The results show that all the measured traits in the cultivars have differed significantly. Highest root yield and white sugar yield are obtained from Callas and Honey cultivars with 125 and 113 ton/ha root yield and 13.5 and 13.6 ton/ha white sugar yield, respectively. Highest sugar and white sugar content with 15.75% and 13.63% are obtained from Sporta. Highest and lowest extraction coefficient of sugar are related to Sporta (86.5%) and Sharif (72.6%), respectively. The range of sodium, potassium, and α-amino nitrogen content has been from 1.54 to 4.26, 2.25 to 3.95, and 1.78 to 3.22 mEq, respectively. In total, to achieve maximum income for the farmer it is recommended that Callas and Honey cultivars or other cultivars that are in the same group with these cultivars should be used to obtain maximum root and sugar yield.

An experiment has been conducted in the form of split plots in a randomized complete block design with three replications at the Agricultural and Natural Resources Research Institute in Zahak to evaluate the effect of drought stress and potassium application on yield and morphophysiological traits of safflower (Goldasht cultivar) under saline irrigation conditions (EC 6 dS.m-1) in 2018-2019. Drought stress irrigation regimes have been tested at three levels (irrigation after 45% (control), 65%, and 85% of admissible moisture depletion) as the main factor, and potassium fertilizer at four levels (0, 75, 150, and 225 kg.ha-1) as the sub factor. According to the findings, drought stress has reduced plant height, number of heads per plant, number of seeds per head, seed and biological yield, and relative water content. The use of potassium, on the other hand, has increased the above traits greatly. Irrigation after 45% moisture depletion increases seed yield by 42.32%, compared to irrigation after 85% moisture depletion. Interaction of drought stress and potassium has had a significant effect on number of branches per plant, 1000-seed weight, leaf chlorophyll index, soluble carbohydrate content, and seed oil percentage, with the highest amount observed after 45% water drainage and application of 225 kg K ha-1.

Application of Azotobacter as a substitute or suitable companion of nitrogen chemical fertilizer with higher efficiency of inputs in safflower plant as a plant adapted to different climates is one of the sustainable agricultural strategies. Therefore, in order to study the effects of Azotobacter chroococcum and nitrogen fertilizer on nitrogen uptake, grain nitrogen and straw, nitrogen efficiency indices and grain yield of six safflower genotypes under rainfed conditions, a factorial experiment has been conducted based on a randomized complete block design with three replications in during growing season of 2015-2016 and 2016-2017 at the Agricultural Research Station Sarableh in Ilam Province. Experimental factors inoculate a combination of seed inoculation with Azotobacter chroococcum with urea chemical fertilizer application at four levels (non-inoculated with Azotobacter chroococcum and urea as control, seed inoculation with Azotobacter, inoculation with Azotobacter chroococcum + 50 Percent N from urea, and inoculation with Azotobacter chroococcum + 100% N from Urea) and six genotypes of safflower. The combined analysis of variance for two years show that the main effects of nitrogen source and genotype and also year× nitrogen source have had significant effect on all of the measured traits and nitrogen efficiency indices. The results from comparison of means show that inoculation treatment with Azotobacter chroococcum + 50% nitrogen fertilizer had higher Nitrogen use efficiencythan 100% nitrogen fertilizer use, with no significant difference in grain yield between the two treatments. Sina genotype with the highest grain yield and nitrogen use efficiency, compared to other genotypes, is more desirable for cultivation in rainfed conditions of the region.

This experiment works on the physiological, growth, and yield responses of sesame to the application of potassium nano-fertilizers, chitosan, and fulvic acid under drought stress in Semnan Agricultural and Natural Resources Research Center as a factorial split-plot based on randomized complete block design with three replications in 2019. The experimental treatments include drought as the main plot (normal irrigation, irrigation cut offin 70 and 60 BBCH as moderate, and severe stress, respectively) and potassium nano-fertilizer (0, 1.5, and 2.5 per thousand) and foliar application (control, chitosan, fulvic acid, and 50% of chitosan+ fulvic acid) as sub-plots.Application of potassium nano-fertilizer under normal and stress conditions significantly cuts chlorophyll b and total, leaf area index, number of capsules, 1000-seed weight, and oil percentage.The highest grain yield belongs to the application of 1.5 and 2.5 per thousand nano fertilizers, using fulvic acid alone or in combination with 50% chitosan (2516, 2277.5, 2506.6, and 2313.2 kg/ha, respectively). The highest oil content has been in 1.5 and 2.5 per thousand nano fertilizer application under normal irrigation, which has increased 13.2% and 15.4%, respectively. Foliar application of fulvic acid with nano potassium fertilizer (1.5 per thousand) under severe drought stress show the highest activity of antioxidant enzymes catalase, peroxidase, ascorbate peroxidase, and superoxide dismutase. In general, the results show that the application of 1.5 per thousand nano potassium fertilizer and combined foliar application of chitosan and fulvic acid under severe drought by improving physiological traits, manage to modify the adverse effects of drought, increasing growth, yield, and quality indices of sesame.

In order to develop winter cultivation and improve crop rotation in the region, an experiment has been conducted to evaluate the effects of sowing date on sunflower cultivars seed yield. It is a split-plot based on completed randomized blocks design with four replications in Safiabad Agricultural and Natural Resources Research and Education Center of Dezful and has taken place during two years (2015-2016). The main plots are consisted of four sowing date levels (23rd Jan, 6th Feb, 20th Feb, and 6th Mar), while the sub plots include nine levels of cultivars (Azargol, Armavirski, Barzegar, Progress, Record, Shams, Farokh, Ghasem, and Gabor). Delay in the sowing date has decreased growth period length and plant height, with the greatest number of seeds per capitulum (684.17) belonging to record cultivar on the first sowing date in the first year and the maximum one (767.47) occurring again to this cultivar on the third sowing date in the second year. The maximum seed yield in the first (3850 kg.ha-1) and second (4088 kg.ha-1) year belong to the first sowing date (23rd Jan) and Azargol cultivar. Based on the results, Azargol cultivar have had the lowest rank, being considered as the cultivar with the highest seed yield on all sowing dates, followed by Record and Armavirski, in the second and third placed, respectively. In terms of stability, considering that Farrokh cultivar also has had the lowest standard deviation, it has been selected as the most stable cultivar.

In order to study the effects of water limitation, biofertilizers and nanosilicon on compatible osmolytes and biochemical traits of triticale, an experiment as factorial was conducted based on randomized complete block design with three replications in research greenhouse faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabil during 2020. The experimental factors were included irrigation at three levels (full irrigation as control; irrigation withholding at 50% of heading as moderate water limitation and irrigation withholding at 50% of booting stages as severe water imitation), application of bio fertilizers (no application of bio fertilizers as control, application of vermicompost, Mycorrhiza, both application vermicompost and Mycorrhiza), foliar application of nano silicon (foliar application with water as control and foliar application of 2 g.L-1 nano silicon). The results showed that both application of vermicompost, Mycorrhiza and foliar application nano silicon under irrigation withholding in booting stage, increased the activity of catalase, polyphenol oxidase enzymes, proline and soluble sugar content (49.17, 50.64, 44.92 and 52.22% respectively) compared to no application of bio fertilizers and nano silicon under normal irrigation condition. Also, both application of vermicompost, Mycorrhiza and foliar application of nano silicon in normal irrigation condition decreased hydrogen peroxide and malondialdehyde content (55.34 and 53.64% respectively) and grain yield increased 59.52% compared to no application of bio fertilizers and nano silicon under irrigation withholding in booting stage condition. It seems that the application of biofertilizers and nano silicon can increase grain yield triticale under water limitation due to improving the biochemical traits.

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 different biochar and chemical fertilizers on growth and nutrient concentrations of sugarcane, a factorial layout has been conducted based on a randomized complete block design with three replications in the greenhouse of Imam Khomeini Agro-Industrial Company in Khuzestan during 2020. The experimental factors include biochar types (sugarcane bagasse, rice husk, rice straw, wheat straw and wood chips) and Chemical fertilizers ((control), (Nitrogen, Phosphorus and Potassium), (Nitrogen and Phosphorus), (Nitrogen and Potassium), (Phosphorus and Potassium), (Nitrogen), (Phosphorus), (Potassium)). The effect of interaction between biochar and chemical fertilizer treatments on the concentration of silicon, phosphorus and potassium of the plant has been significant at one percent and on the concentration of plant nitrogen at five percent. Also, the effect of interaction between biochar and chemical fertilizer treatments on fresh and dry weight of the plant has been significant at one percent and on plant height at five percent. The highest concentration of Si has been gained from the treatments of mixture of rice straw biochar and nitrogen, phosphorus and potassium fertilizer, mixture of rice straw biochar and nitrogen and phosphorus fertilizer. Compared to the control, the treatments of mixture of rice straw biochar and nitrogen, phosphorus, and potassium fertilizer have had the highest concentration of nitrogen and phosphorus in the plant, increasing the concentration of nitrogen and phosphorus by 49% and 36%, respectively. The highest height and fresh weight of the plant are related to the treatments of mixture of rice straw biochar and nitrogen, phosphorus and potassium fertilizer. According to the results, the application of biochar and chemical fertilizers mixture is recommended to increase the growth and nutrient concentrations of sugarcane.

Global climate change is among the most important agricultural and food security challenges. This study tries to investigate the effect of climate change on potential yield and water productivity of forage maize (Zea mays L.) in Iran. Two scenarios of RCP4.5 and RCP8.5 are used to predict the future climate (2050s) and climate data of 2001-2015 have been used as the base period. Potential yield is estimated using SSM-iCrop2 model according to the GYGA protocol and the climate changes for both scenarios are applied in the model. The results show that the climate change will not have a considerable effect on forage maize yield compared to the current conditions (85.6 ton ha-1) and will only lead to an increase of 0.9% and 1.6% in on both scenarios, respectively. This may be attributed to maize being a C4 plant and thus non-effectiveness of CO2 increase on its growth. Also, the temperature will remain in optimum range for maize in most of the main regions for forage maize cultivation areas in Iran. Water productivity in both scenarios will increase by 0.4% and 1.6%, compared to current conditions (10.4 kg m-3), respectively, which may be due to increased CO2 concentration and more closure of stomata. Also, improved water productivity in forage maize may be attributed to increase yield potential due to the fact that no considerable changes are observed in terms of the required water, evapotranspiration and irrigation times.

seed polishing treatment on germination and seedling growth of different sugar beet cultivars, a experiment was conducted in a completely randomized design with three replications in the laboratory and greenhouse of the Faculty of Agriculture, Shahrekord University in 2020-2021. The first factor consisted of five monogerm cultivars of sugar beet (Shokofa, Arta, Aria, Sina and Octaban) and the second factor consisted of three levels of seed polishing (control, abrasion of 10% of seed husk weight and , abrasion of 30% of seed husk weight). The results of analysis of variance showed that the effect of cultivar and the interaction of cultivar and abrasion on all traits were significant. Comparison of mean interactions showed that Aria cultivar and 30% abrasion treatment had the highest germination percentage (83.5 percentage), germination rate (7.6 seed/day), and mean daily germination (5.96 seed/day) Meanwhile, the highest coefficient of seed length vigor index (10.18) were related to Ekbatan cultivar and 30% abrasion treatment. The highest fresh weight of plumule (0.25 g) and radicle (0.053 g) belonged to Shokofa cultivar without abrasion, the highest amount of chlorophyll b (2.77 mg/g fresh weight) and related to Arta cultivar and 30% abrasion, the highest amount of chlorophyll a (4.19 mg/g fresh weight ) was observed in Shokofa cultivar with 30% abrasion In general, it can be concluded from this study that polishing of 30% weight improves the germination and growth characteristics of sugar beet seeds and among the cultivars tested, Aria is more affected by abrasion than other cultivars

In order to evaluation of the spraying time and cobult nanoparticle fertilizer using chemical and green chemistry methods on morphophysiological indices of cowpea, this research was conducted in a factorial experiment in a the experiment was conducted Randomized Complete Block Design (RCBD) with three replications in Agricultural Research Institute University of Zabol in 2017.The experimental included 4 levels of treatments: (Cobult  nanoparticles of plant origin, chemical origin, plant and chemical composition and control), as the first factor and time of spraying in 2 levels (Step 4 leaf and Step 6 leaf as the second factor). The plant density of cowpea was 20 plants/m2 and irrigation was performed twice a week. The results of analysis of variance showed that the time of foliar application and application of nano particles of chemical and plant origin had a significant effect on all studied traits.  Based on the results of average comparison, the highest amount of chlorophyll a (13.25 μg/g leaf), chlorophyll b (7.50 μg/g leaf), carotenoids (3.63 μg/g leaf), as well as plant height (34.84 %), number of pods per plant (28.26%), biological yield (45.64%), economic yield (59.10) compared to control treatment, iron (0.26 ppm) and leaf protein ( (46/14 ppm) was obtained from the six-leaf stage and from the combined application of cobalt nanoparticles with chemical and plant origin. In terms of all the measured traits, it seems that the simultaneous application of cobalt nanoparticles chemically and vegetative, through improving the photosynthetic system, increasing leaf duration and photosynthesis, will lead to increased biological and economic yield.

The use of compounds that can improve plant tolerance to abiotic environmental stress, including salinity, is important. To evaluate the adjustment of salinity stress using humic acid (HA), a factorial layout is conducted based on a complete randomized design with three replications on the Hypericum perforatum L. as an Iranian medicinal plant are collected from Hamadan province in the tissue culture laboratory of the Faculty of Agriculture, Sayyed Jamaleddin Asadabadi University during 2019. Experimental treatments include NaCl as salinity at three levels (such as 0, 50, and 100 mmol.L-1) and HA at four levels (control, 25, 50, and 100 mg.L-1). Results indicate that the plants treated with 50 mg.L-1 HA without salinity have had the highest germination percentage (98.65), germination rate (38.94) and root length (34.21 mm). The highest plant height, fresh and dry weight of both shoots and roots and total chlorophyll are obtained under control conditions and HA with a concentration of 100 mg.L-1. On the contrary, the highest amount of phenol in the treatment is 50 mmol.L-1 salinity and HA with a concentration of 50 mg.L-1. In the treatment of 100 mmol.L-1 salinity and HA with a concentration of 50 mg.L-1, the highest amount of total antioxidants (99.77 mg/g FW) and total flavonoids (2.39 mg/Qe g FW) and the lowest amount of hydrogen peroxide (9.12 µg/g FW) are obtained. Results show that the mitigating effect, especially the application of HA of 50 mg.L-1 levels, can affect the physiological processes and morphological traits of the Hypericum perforatum L. under salinity stress.

Natural habitats of licorice have decreased dramatically while the demand for this plant rises. Licorice seeds exhibit a low germination rate due to secondary dormancy imposed by the hard seed coat. In this study, conducted in the spring of 2021 at Shahid Bahonar University of Kerman, Iran, the interaction effect of sulfuric acid (95-97%, 60 min) scarification with gibberellic acid (GA) concentrations (0, 100, 250, 500, and 1000 mgL-1) has been studied in a factorial experiment based on a completely randomized design with four replications. Results show that although there has been no difference in germination between GA levels for scarified seeds, GA at 250 mg L-1 improves germination by 36%, compared to the control in non-chemically scarified ones. In contrast, increasing in GA concentrations increased seedling length, plant height, number of leaves and compound leaves, leaf area, fresh and dry weight of shoot and root, while decreased chlorophyll index (SPAD). As a result, chemical scarification, application of GA at 1000 mg L-1, and germination at room temperature can effectively increase the germination rate and uniformity as well as early growth of licorice plant.

This study was carried out to assess yield, yield components and quality traits of dragon’s head (Lallemantia iberica L.) ecotypes’ seeds grown using some anti-transpirant agents in rainfed system in two regions of Iran including Karaj & Khorramabad in 2018. The experiment was performed based on a randomized complete block design (RCBD) with a 4×3 factorial arrangement consisting of three replications. The first factor consists of four different ecotypes of dragon’s head (Kurdistan, Takab, Nazarkahrizi and Kalibar) and the second factor including three anti-transpirant compounds (kaolin with a concentration of 5 Percent, chitosan with a concentration of 1 Percent and Ista with a concentration of 2 Percent) and no anti-transpirant (control). The results indicated that the triple interaction of ecotypes, anti-transpirant and location on most of the studied traits was significant. Among anti-transpirant, chitosan had the greatest effect on cultivated ecotype & increased grain, biomass, oil and mucilage yields by 20, 4, 11, and 18 Percent, respectively. Also, Nazarkahrizi, Kalibar, Kurdistan and Takab ecotypes cultivated in Karaj had the highest values in the studied traits under foliar application with anti-transpirant, respectively. According to the studies conducted in this study, the selection of a suitable ecotypes with the region and the use of antiperspirants improve the yield & yield components, quality traits of dragon’s head in rainfed cultivation conditions.

An experiment was conducted to evaluate the effect of different levels of chitosan and salicylic acid on morphological traits of the medicinal plant Galega officinalis L. in field conditions in a completely randomized design with three replications in 2017 in the research farm of Islamic Azad University, Miyaneh Branch. The treatments included foliar application with four levels of salicylic acid (0.5, 1, 2, and 3 mM/l), foliar application with four levels of chitosan (0.2, 0.4, 0.6, and 0.8 g/l) and foliar application with distilled water (the control). The results showed that foliar application of biological stimulants had a significant impact on all evaluated traits, except plant height and leaf dry weight. By increasing the concentration of chitosan and salicylic acid, the fresh and dry weight of the stem have decreased so that the highest values in the two traits have belonged to the treatments of chitosan 0.4 and 0.2 g/l and 1 and 0.5 mM/l salicylic acid. Maximum number of internodes (with a numerical mean of 4.80), root length in chitosan treatment (0.4 g/l), and the highest number of leaf (at a concentration of 0.6 g/l chitosan) has been observed. In the study of leaf and root characteristics, chitosan with concentrations of 0.2 and 0.4 g/l and in inflorescence characteristics, salicylic acid with concentrations of 2 and 3 mM/l have been more effective. In general, the use of concentrations of 0.4 and 0.2 g/l chitosan have had a more optimal effect on the morphological traits of the medicinal plant Galega officinalis L., making it ultimately recommended thanks to its positive effect on most of the plant's growth characteristics due to its rapid absorption to achieve the desired yield in a sustainable agricultural path.

To investigate the effect of different levels of foliar applications of salicylic acid and jasmonic acid on biochemical characteristics and yield of Thymus vulgaris under drought stress conditions, a split factorial experiment has been performed based on randomized complete design with three replications during cropping seasons of 2019-2020 in Varamin region. The main factor include irrigation levels (60 (normal) and 110 mm of evaporation from the evaporation pan (drought stress)), with the sub factors being different levels of foliar application of salicylic acid (three level: control (zero), 25, and 50 mg l-1) and jasmonic acid (three level: control (zero), one, and two mg l-1). The effect of irrigation× foliar application treatments has been significant for all studied traits at 1%. The highest plant height (38.2 cm), wet and dry weights (7112.3 and 1778.7 kg h-1), percentage of secondary metabolites (essential oil 0.28 and thymol 60.9%), and concentrations of salicylic and jasmonic acid of leaves and the lowest activity of antioxidant enzymes (SOD, CAT and GPX) of thyme are observed in normal irrigation with 50 and 2 mg -1 salicylic and jasmonic acid treatment. Thus, external use of salicylic and jasmonic acid (50 and 2 mg -1) in drought stress conditions can be considered in improving related traits of yield and increasing the production of thyme.

In order to investigate the effects of integrated management of chemical and biological fertilizers on physiological traits, and grain yield of black cumin (Nigella sativa L.) under different irrigation levels, a split-plot experiment has been conducted based on a randomized complete block design with four replications at research farm University of Kurdistan in the spring of 2016. Two irrigation levels (irrigation at 100% and 70% of the plant water requirement) are randomized on the main plot. Five fertilizer levels (including 100% chemical fertilizers, 80% chemical fertilizers + biofertilizers, 60% chemical fertilizers + biofertilizers, 40% chemical fertilizers + biofertilizers, and non-fertilizer application) are randomized on a sub-plot. The results reveal that under irrigation at 70% of the plant water requirement conditions, proline concentration, soluble carbohydrates concentration, and lipid peroxidation have increased, while the values of other studied physiological parameters as well the grain yield have dropped. The combination of biological and chemical fertilizers positively affect the studied physiological traits and grain yield, such that the highest grain yield belongs to the combined treatment of 60% chemical fertilizers + biofertilizers (798.18 kg ha-1), showing an increase of 37.22% compared to the control (without fertilizer). Due to the positive effects of combining bio-chemical fertilizers on physiological parameters and grain yield, it is recommended to replace the combination of bio-chemical fertilizers instead of employing only chemical fertilizers.

Based on the nutrition importance of nut squash seed and its commercial value, an experiment has been conducted in randomized complete block design with 30 squash landraces collected from West Azerbaiejan, Golestan, and Isfahan Provinces with three replications at Minab Agricultural Research Station during 2018-2019 and 2019-2020. It tried to compare seed yield and yield components of different nut squash genotypes in autumn planting time of Hormozgan Province. The field was prepared in August and the seeds were sown in late September. The evaluated characteristics included plant length, the number of fruit in the plant, average fruit weight, fruit length and width, fruit yield, seed yield, the weight of 100 seeds, hollow seed percent, kernel percent (kernel/seed ratio), and seed bitterness percent. According to the results of the important traits such as seed yield, seed size, hollow seed percent as well as kernel percent, the genotypes Kh6, Kh5, CP7-A, Kh2 selected CP3, CP4-B self, CP7-B self, Isfahan Pumpkin, CP4-E, O6, CP2-B, and N2 have had more suitable status than others. By evaluating all examined parameters and based on the production costs and net profit, there is the possibility of nut squash planting in Minab region with some genotypes including the collected genotypes from Khoi region including Kh6, Kh5; the genotypes in Golestan province including CP7-A, CP7-B-Self, CP4-E, and CP2-B; Isfahan Pumpkin.

The present study tries to quantify germination response of Guar (Cyamopsis tetragonoloba) to temperature and water potential. Performed in Vali-e-Asr University laboratory in 2020, it is a completely randomized design in a factorial arrangement with four replications. It aims at quantifying the rate of Guar germination in response to temperature, and water potential. The seeds have been germinated at seven temperatures (5, 10, 15, 20, 25, 30, and 35°C) and six water potentials (0, -0.2, -0.4, -0.6, -0.8, and -1 MPa). The results reveal that the Beta function is suitable for describing the response of seed germination temperature, and water potential. Under different water potentials, base, optimum, and maximum temperatures have been 7.3-12°C, 22.1-25.8°C, and 32.2-36°C, respectively. The hydrothermal time parameters are 268.3 bar °C h, -1.103 MPa and, 8.36°C for ɵHT (hydrothermal time constant). The data obtained from these models can be used to establish and manage guar for cultivation in different areas.

Numerous studies have been performed on the effect of rootstock and cultivar on physicochemical traits of apple fruit with their results showing different effects of these two factors. In order to study three vegetative rootstocks on some quantitative and qualitative characteristics of apple cultivars "Golden Delicious" and "Red Delicious", an experiment was carried out in factorial design based on randomized complete blocks with four replications in orchard of Mashhad Agricultural Research Center in 2021. Fruit quantitative and qualitative characteristics, including weight, volume, density, length, diameter, firmness, pH, total soluble solids, phenol content, antioxidant properties and anthocyanin have been measured. The highest amount of total phenol (652.9 μg.g-1FW) and anthocyanin (35.9 mg.g-1FW) has been measured in "Red delicious" on M9 rootstock. The results of this study show that "Red delicious" has had the highest amount of diameter (78/64 mm) and weight (166/9 g). The highest amount of fruit firmness has been observed in M9 rootstock (5/64 kgcm-3). In general, the results of this study indicate a different effect of rootstock and cultivar interaction on the studied characteristics. Depending on the purpose of gardener, different grafting compounds can be recommended "Red delicious" on M9 and MM106  rootstock with highest amount of total phenol and anthocyanin is suggested as a valuable grafting compounds in terms of health benefits under Mashhad Climatic Conditions.

Pre-harvest citrus fruit splitting is a physiological disorder that causes significant damage to producers of susceptible cultivars by reducing the amount of crop available on the market. Proper management of tree nutrition and paying special attention to the three key elements of potassium, calcium, and boron, which are involved in the strength of cell walls and fruit peel flexibility, can be effective in reducing the fruit splitting severity. Therefore, an experiment has been carried out in the Ramsar (Citrus and Subtropical Fruits Research Center) during 2018 and 2019 to investigate the effects of foliar application of 1.0% potassium nitrate, 1.0% calcium nitrate, and 0.5% boric acid at the end of June drop on reducing the severity of splitting and some fruit traits of Page mandarin. This study is performed according to a combined analysis in time with two factors including years of experimentation and different treatments of foliar application of nutrients, based on randomized complete block design with three replications. The results show that the treatments especially 1.0% potassium nitrate have reduced pre-harvest fruit splitting, increased the yield, and improved the quantitative and qualitative fruit traits. However, they have had no significant effect on the activity of polygalacturonase enzyme, cell density of blossom-end, and navel diameter. Overall, foliar application of nutrients, especially 1.0% potassium nitrate, could be suggested as an effective approach to control pre-harvest fruit splitting and boost the quantity and quality of page mandarin fruit.