مجله به زراعی کشاورزی
سال بیست و پنجم شماره 1 (بهار 1402)

In order to investigate the effect of seed priming (pretreatment) and coating on seedling characteristics, root morphology and phenological stages of rice, a two-year experiment has been conducted in the Rice Research Institute of Iran (Rasht) between 2020 and 2021. The experiment is performed as a factorial in a randomized complete block design with three replications. Experimental factors include two rice cultivars (Hashemi and Gohar) and the seed pretreatment of rice cultivars in seven levels, including (1) priming with calcium chloride (-1.25 MPa in 24 hours), (2) priming with potassium chloride (1.25 MPa in 24 hours), (3) priming with zinc sulfate (concentration of 0.5 mM in 12 hours), (4) hydro-priming (48 hours) + coating the seeds with calcium chloride, (5) hydro-priming (48 hours) + coating with potassium chloride, (6) hydro-priming (48 hours) + coating with zinc sulfate, and (7) hydro-priming (48 hours as control). The results show that the highest percentage and germination rate has been observed with 99.5% and 0.23 seeds per day under seed priming with potassium chloride in the Gohar cultivar, respectively. The lowest time required to achieve 90% emergence has belonged to Hasehmi and Gohar cultivars through priming with potassium chloride and calcium chloride. The highest root length (with 24.6 cm) has been observed in priming with potassium chloride in the Gohar cultivar. The highest root dry weight in Hashemi and the Gohar cultivars has been 2.14 and 4.9 g, respectively, in priming with potassium chloride. The results also show that the maximum root volume and area are obtained with 43 cm3 and 155.28 cm2 in priming with potassium chloride in Gohar cultivar, respectively. The least time required to achieve maximum tillering, 50% flowering, and physiological maturation takes place in priming treatment with calcium chloride and potassium chloride. Seed priming with potassium chloride and coating with calcium chloride have increased grain yield by 22% and 13%, respectively, compared to the control. The highest biological yield is observed in potassium chloride priming and coating with calcium chloride treatments with 5552 and 5414 kg. ha-1 in Gohar cultivar, respectively. In general, rice seed priming with calcium chloride and potassium chloride promoted plant yield by improving seedling characteristics, root system, and phenological stages.

In order to determine drought stress in the final stages of flowering up to 50% pods and pods until harvest tolerance in canola genotypes via yield-base stress tolerance indices, a split plot experiment has been conducted based on the randomized complete block design with three replications at the research farm of department of plant production and genetics, Agricultural Sciences and Natural Resources University of Khuzestan, Iran during 2020-2021. The main plots include three irrigation treatments: the control (without any interruption of irrigation), interruption of irrigation in the beginning of flowering stage (phenology code 60) to the formation of 50% pods (phenology code 75), and  interruption of irrigation in the stage of formation of pods until harvest (Phenology code 99) in the main plots. Also, the genotypes (Long pod, Aram, RGS 003, Jankom, Solar, Hayola 4815, Mahtab, Julius, Agamax, and Sala) are arranged in sub-plots with respect to irrigation treatments. They are reliable indices to identify drought tolerant rapeseed cultivars. Indices MP, GMP, and STI are the most suitable ones to evaluate drought stress tolerance in different treatments. The highest grain yield of control treatment belongs to Hayola 4815, Long pod, Solar genotypes (2093.8, 1791 and 1700 kg / ha), and the lowest to Jankum genotype (832.1 kg / ha), in flowering Stress up to 50% pods. The highest grain yield is observed in Hayola 4815 (1563.9 kg / ha) and Lon gpod (1150.9 kg / ha) and the lowest grain yield in Jankum and Mahtab genotype (540, 935.5 kg / ha).

Considering the importance and value of water and optimal use of nitrogen for maintaining production productivity and simultaneously reducing the negative environmental effects, two experiments have been conducted in 2017-2018 and 2018-2019 cropping seasons in the research farm of the Faculty of Agriculture, University of Kurdistan. The experiments are performed as a split plot in a randomized complete block design with four replications. Experimental treatments include the different levels of irrigation as the main plots (25% (W1), 50% (W2), 75% (W3), and 100% (W4) of crop water requirement) and different levels of nitrogen fertilizer as sub-plots (25% (N1), 50% (N2), 75% (N3), and 100% (N4) based on crop nitrogen requirement). Results show that all the studied traits with the exception of the time of reaching the maximum pod area index are affected by the main and interaction effects. The highest grain yield is obtained in W4N4 treatment (5069 kg.ha-1) and the lowest grain yield in W1N1 and W1N2 treatments at 880 and 899 kg.ha-1, respectively, which has been decreased by 82.6% and 82.2%, compared to the control, respectively. The grain and biological yield of W4N3 (4826 and 17589 kg.ha-1) and W3N4 (4712 and 17657 kg.ha-1) treatments, represent 25% reduction in nitrogen consumption and 25% reduction in water consumption, respectively compared to the control. W4N4 is recognized as the superior treatment in this study for improving productivity.

Determining the appropriate planting arrangement and plant density leads to better productivity of resources and increased yield per unit area. In this regard, an experiment was conducted in the Ardabil agricultural and natural resources research and education center (Moghan) during the 2021 crop year. This experiment uses a strip plot design based on randomized complete blocks with four replications. Its main factor is the effect of planting rows at a spacing of 30, 45, and 60 cm with planting spacing of 5, 8, 11, and 14 cm serving as the subfactor. According to the results, by increasing the distance between plants on the planting row, the maximum days to flowering initiation (47.25 days), growth period (122.25 days), stem diameter (8.33 mm), number of branches (2.97), and capsule length (24.20 mm) of sesame can be observed at a planting distance of 14 cm between the plants. Row spacing of 45 to 30 cm increases the number of capsules per plant, the number of seeds per capsule, and 1000-seed weight of sesame by 33%, 18.50%, and 16%, respectively. The highest seed yield, fresh and dry weight belong to 1455.40, 5021.80, and 1280.73 kg/ha, respectively, at 45 cm distance between planting rows. The results from this experiment show that planting arrangement with a distance between plants of 14 cm and a distance between planting rows of 45 cm, with optimal use of environmental resources is suitable for cultivation in Moghan plain and recommended for local farmers.

In order to evaluate the quantity and quality of safflower cultivars forage in three forage harvesting times based on plant phenological stages, the present study has been conducted in a randomized complete block design with split-plot in time arrangements with three replications at the Seed and Plant Improvement Institute (SPII), Karaj, Iran, during 2018-2019 and 2019-2020 cropping seasons. The main factor includes three safflower cultivars (Goldasht, Golmehr, and Parnian), with three forage harvesting time (namely stem elongation, branching, and flowering stages) considered as the sub-factor. The effect of year only on plant height and water-soluble carbohydrates (WSC) has been significant (P≤0.05). The results show that the interaction effect of cultivar × harvesting time on the fresh forage yield, plant height, WSC, and neutral detergent fiber (NDF) has been significant (P≤0.01). The highest fresh forage yield (52103 kg ha-1) is obtained by harvesting the Golmehr cultivar at the beginning of flowering; however, the highest dry matter yield is observed in Golmehr and Parnian cultivars. The highest dry matter yield has been observed in the branching stage (11900 kg ha-1), with the crude protein content in this stage being 14.57%. In contrast, the maximum crude protein content is observed in the flowering stage (19.22%), even though the mean dry matter yield at this stage has been 9937 kg ha-1. The maximum and minimum RFV (130.3% and 92.3%) are recorded in the forage of Goldasht and Golmehr cultivars, respectively. Therefore, among the studied cultivars, Parnian, and among the growth stages, forage harvesting at the branching stage is introduced as the superior treatment to achieve maximum yield and quality of safflower forage.

Drought, being the most common abiotic stress, is a major factor in crop yields as it limits crop production on a global basis. To evaluate the effects of foliar application with potassium (K) and zinc (Zn) in the pollination stage on morphological and physiological characteristics of wheat under water stress conditions, a split-factorial layout based on a randomized complete block design (RCBD) with three replicates have been carried out at the experimental farm of the Research, Education and Extension Center of Agriculture and Natural Resources of Hamadan during 2017-2018. The main plot includes irrigation levels (normal and water stress) and the subplot, two factors of foliar application of potassium (K) and zinc (Zn) fertilizers. Potassium fertilizer from K2O source (40%) includes 2 liters per ha at three levels; I) without fertilizer (the control), II) leaf spray at the beginning of booting, and III) leaf spray after pollination. Also, zinc fertilizer from water-soluble zinc source (10%) includes four liters per ha in three levels: I) without fertilizer (the control), II) leaf spray at the beginning of booting, and III) the use of leaf spray after pollination. The results of the analysis of variance show a significant difference between treatments in all studied traits. Significant differences in all of the traits are observed under stress and normal irrigation. Co-application of potassium (K) and zinc (Zn) fertilizers, compared to the control, has increased evaluated morphological indices of HI (21%), grain yield (52%), total yield (29%), and TKW (25%) under stress conditions. Therefore, according to the results, the use of K and Zn fertilizers as a foliar application at the beginning of booting reduces the harmful effects of drought stress on the plant, increasing the yield and morphological characteristics of wheat.

In order to investigate the effects of reduced row spacing from usual 75 cm to 25 cm (UNR), an experiment has been conducted in two locations: Davarabad agricultural research station (Semnan Province) and Varamin Central Agricultural Research Station. The experimental design is RCBD laid out in split plots with three replications. The main plots are the planting dates (May 22 and Jun 5, 2020) and five cultivars, i.e. Khorshid, Kashmar, Sajedi, Hekmat, and Khordad serve as the sub plots. The results show that location effect on vegetative and reproductive attributes has been significant. UNR boosts the yield in Aradan, but in Varamin region, this planting method, not only has failed to increase the yield, but has reduced it significantly. This is due to reducing the boll number as a result of rank growth of plants in UNR system. Reduction of row spaces from 75 to 25 cm enhances the number of monopodials, sympodials, and plant height. In Varamin, plant height of all cultivars are higher than 119 cm. the highest yield in this region obtained from Khordad as Control (3886 kg seed ha -1). The highest yield in Aradan, obtained from Khorshid (5702.5 kg seed ha -1) in UNR system. This shows that the UNR planting of zero type varieties is more adabtable for Garmsar condition than that of Varamin.

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.

Water deficit is one of the most important limiting factors of production in crops. The present study was conducted in 2019 to investigate the effect of different irrigation times and foliar application of humic acid on morphophysiological traits and yield of black beans as a split plot in a randomized complete block design with three replications at Zahak Agricultural Research Station in Sistan and Baluchestan Province. The main factor involves three irrigation treatments, including irrigation from planting to harvest, irrigation from planting to flowering, and irrigation from flowering to harvest, and the secondary factor includes foliar application at four levels of humic acid (0, 1, 2, and 3 per thousand). By increasing drought stress levels, plant height and width, fresh and dry forage yield, leaf area (in both stem and flowering stages), photosynthetic pigments, nitrogen, phosphorus (3.39%), potassium (20.6%), calcium of leaf, grain yield (11.27%), and biological yield (60.22%) has decreased, whereas proline content (31.88%) has increased, compared to the control. Also, by increasing humic acid levels, the values ​​of all studied traits has increased. Humic acid has had a positive effect on black bean plant traits under drought stress conditions, so that its concentration of three per thousand reduces the adverse effects of drought stress, increasing the tolerance of black bean crop. In general, complete irrigation and application of three per thousand humic acids for the production of black beans seems appropriate. It is suggested that in future research, soil application of humic acid consumption should be investigated to compare the efficiency of the methods used.

In order to study the effects of nitrogen starter, putrescine, and nano silicon on yield and some physiological and biochemical traits of rainfed chickpea (Cicer arietinum L.), an experiment was carried out as factorial based on randomized complete block design with three replications in a farm near Ardabil in 2021. The experiment factors include nitrogen starter (no-nitrogen starter, application of 20 and 40 kg.ha-1 by urea), putrescine foliar aplication (foliar application with water, application of 0.5 and 1 mM putrescine), and nano silicon (foliar application with water, application of 25 and 50 mg.L-1). Means comparision show that the highest level of nano silicon, putrescine, and nitrogen starter have increased chlorophyll a, chlorophyll b, total chlorophyll, and proline content (139%, 137%, 138%, and 80%, respectively), compared to no application of nano silicon, putrescine, and starter nitrogen. The highest level nano silicon and putrescine has increased the activity of catalase, peroxidase enzymes and grain yield (40%, 16.3%, and 16.6%, respectively), compared to no application of nano silicon and putrescine. Maximum quantum yield of photosystem II (7.4%, 8%, and 15.5%, respectively) and the activity of polyphenol oxidase enzyme (17%, 9%, and 21%, respectively) are obtained at the highest level starter nitrogen, putrescine, and nano silicon. It seems that the application of nano silicon, putrescine, and starter nitrogen can increase grain yield of chickpea under rainfed condition as it improves physiological and biochemical traits.

This field experiment is arranged in a split-split plot based on a randomized complete block design replicated three times during the growing season of 2019 at Shahid Bahonar University of Kerman, Iran. Nitrogen fertilizer rates (no-application, 50%, and 100%; 0, 75, and 150 kg urea per hectare) serve as the main factor, inoculation with growth-promoting bacteria (non-inoculation and inoculation with Pantoea agglomerans) as sub factor, and different fenugreek and black cumin cropping systems (100:0, 75:25, 50:50, 25:75, and 0:100) as sub-sub factor. Biomass, yield, nitrogen use efficiency (NUE), agronomy efficiency of fertilizer (AEF), and land equivalent ratio (LER) are determined. The results show that the highest biomass and NUE of studied plants are obtained from 100% fertilization and bacteria inoculation in monoculture. The total LER is also significantly improved by fertilization (between 28-51%) and bacteria inoculation (23%), showing a higher advantageous in 25:75 and 50:50 cropping patterns with LER values of 1.732 and 1.688, respectively. In contrast, reducing 50% of fertilization under bacterial inoculation increases the AEF, especially in fenugreek monoculture. Fertilization increasing the total NUE and bacteria inoculation results in the highest NUE, particularly at increased ratios of fenugreek. Fenugreek:black cumin cropping ratio of 25:75 under 100% N fertilization and bacteria inoculation with LER ≈ 2 has been the best treatment combination for gaining maximum overall productivity. Fertilization with 50% N inoculated with bacteria in the same cropping pattern can be recommended when fertilizer application is restricted. The present research suggests that the integrated application of bacteria and fertilization can enhance the overall efficiency of intercropping.

In order to evaluate the biochemical properties of dragon’s head (Lallemantia iberica L.) ecotypes’ using some anti-perspirants in rainfed conditions in the crop year 2018, an experiment has been conducted in Karaj and Khorramabad regions. The experiment is based on a randomized complete block design (RCBD) with a factorial arrangement, consisted of three replications. The first factor involves four different ecotypes of dragon’s head (Kurdistan, Takab, Nazarkahrizi, and Kalibar) and the second factor includes three anti-transpirant compounds (kaolin with a concentration of 5%, chitosan with a concentration of 1%, and Ista with a concentration of 2%) as well as no anti-transpirant (control). The results show that using anti-transpirants has increased the amount of the activity of catalase and peroxidase enzymes. Ista anti-transpirant has had a greater effect on enzyme activity than kaolin and chitosan. The highest amount of peroxidase and catalase (0.51-0.39 unit mg/protein) are obtained from the ecotypes of Kurdistan treated with Ista and Karaj cultivation, respectively. In addition, the highest grain yield and biomass yield are obtained from treatment with chitosan, which has increased by 4% to 20%, compared to the control, respectively. Based on the results, using anti-transpirants in dryland cultivation conditions improves most of the studied yield traits and biochemical traits compared to the control.

Indian meal moth Plodia interpunctella Hübner (Pyralidae) is one of the most important pests of storage products in Iran, which is controlled by chemical fumigants. The use of plant essential oils and their compounds can be a suitable alternative to conventional fumigants due to their low risks to mammals. The present study invesrigates the mortality, inhibition of alpha-amylase enzyme, and the total protein content of Indian meal moth larvae (Plodia interpunctella (Hübner)) affected by saffron petal extract with high concentration of anthocyanin under experimental conditions. The concentrations have been 500, 690, 1000, 1380, and 2000 ppm, used against the fifth-instar ‎larvae of the pest in four replications within 24 and 48 h. The lethal concentration to kill fifty percentage of larvae (LC50) by saffron petal extract after 24 and 48 hours is estimated to be 2244.950 and 1434.828 ppm, respectively. Alpha-amylase enzyme activity in the fifth instar larvae of Indian meal moth, treated by saffron petal extract, has been significantly different from the control. The highest activity of the alpha-amylase enzyme in pest larvae treated by saffron petal extract has been recorded with 83.1%, and the inhibitory rate of this enzyme has been 21.8%, which is significantly different from control. Also, the amount of protein in the larvae affected by this extract significantly differs from the control groups. Therefore, due to its fumigant toxicity and the alpha-amylase inhibitory activity of Indian meal moth larvae, saffron petal extract can be considered for additional researches on managing this pest based on an ecological principle.

In order to evaluate some morphological and chemical characteristics of quinoa, a split plot experiment has been conducted in a randomized complete block design with three replications during 2019-2020 cropping season, at the Agricultural Research Station of University of Zabol, Iran. Vermicompost at three levels (0, 5 and 10 ton/ha) has been considered the main factor and chemical fertilizer at four levels (25, 50, 75 and 100%), the sub-factor. The main effect of vermicompost is significant on morphological traits such as plant height, 1000-seed weight, biological yield, grain yield, and harvest index. Interaction of vermicompost and chemical fertilizer is significant on chemical properties, including proteins and photosynthetic pigments. Application of 10 tons of vermicompost per hectare leads to the maximum level of plant height, 1000-seed weight, biological yield, grain yield, and harvest index. Also, the highest amount of photosynthetic proteins and pigments are achieved from combined application of 10 tons/ha of vermicompost and 50% chemical fertilizer (25 kg/ha Urea+ 50 kg/ha triple superphosphate + 50 kg/ha potassium sulfate). Totally, results show the positive effects of vermicompost on the morphological and chemical properties of quinoa. It can be concluded that the combined use of chemical fertilizers and vermicompost can increase the yield of quinoa, while reducing the use of chemical fertilizers and thus reduce the environmental impacts caused by them..

Quinoa is one of the salinity tolerant plants, capable of playing an important role in providing human food in the future. In order to investigate the effect of salinity stress on physiological traits and yield of quinoa cultivars, a two-factor factorial experiment was conducted as random complete block design with three replications in 2020 year under greenhouse conditions. Experimental treatments include three quinoa cultivars (Titicaca, Q26, and Giza1) and three salinity levels (0, 15, and30 dS/m). Salinity stress reduced traits such as photosynthetic pigments, relative leaf water content, and grain yield. The chlorophyll a and b content in control conditions, compared to the salinity level of 30 dS/m, have decreased by 46% and 77%, respectively, with the yield dropping by 35.6%, but the decrease in relative water content has been 12.6%. Electrolyte leakage, proline and malondialdehyde content, catalase, and guaiacol peroxidase activity have increased under salinity stress condition. The Q26 cultivar has had the highest content of carotenoids, chlorophyll a, relative water content, soluble proteins, proline, and catalase activity, compared to the others. Titicaca cultivar has had lower malon-dialdehyde (MDA) content and electrolyte leakage than Q26 and Giza1 cultivars, which indicates the least damage to cell membranes, being superior to the other two cultivars. Giza1 cultivar also has had higher chlorophyll b and carotenoids content than the other two cultivars. Q26 and Giza1 cultivars are probably the most resistant and sensitive cultivars to salinity stress, respectively.

In order to investigate the effects of irrigation, planting date, and biofertilizers on phenological traits, yield, and some qualitative traits of quinoa as a new plant, an experiment has been conducted on a farm located in Bilehsvar region of Ardabil Province in two cropping years from 2019 to 2021 in split - split plot design based on a randomized complete block design with three replications. Experimental factors include irrigation at three levels, including (complete irrigation, irrigation termination in budding stage, and irrigation termination in seed filling stage) as the main factor, planting date at three levels (namely 27 July, 11 August, and 27 August) as the sub-factor, and four levels of nitrogen biofertilizer (the control, seed inoculant with Azotobacter, inoculant with Azospirillum, and inoculation with a mixture of Azotobacter and Azospirillum) as the sub-sub-factor. The results show that the use of complete irrigation with a planting date of 27 July and inoculation of Azotobacter and Azospirillum biofertilizers has increased the length of phenological stages and 1000-seed weight. In terms of harvest index, complete irrigation treatment with planting date of 27 July, and combined inoculation of biofertilizers have had the highest value, in terms of protein percentage and saponin content of seed, irrigation interruption at the budding stage with planting date of 27 July, while co-inoculation with biofertilizers has given the best results, and the highest biological yield (620 g/m2) and grain yield (304.97 g/m2) have been obtained from complete irrigation treatment with planting date of 11 August and co-inoculation of biofertilizers.

Salinity can prevent the uptake of soil mineral ions due to the negative effect of sodium ions and disturbance of ion balance, but the use of Trichoderma biocompounds improves growth under salinity stress. To investigate the effect of four salinity-resistant Trichoderma strains on growth traits and mineral element uptake of eggplant seedlings under stress conditions, an experiment has been performed in a completely randomized factorial design with three replications in the greenhouse of Vali-e-Asr University of Rafsanjan during 2016-2017. The first factor is salinity in four levels including the control and concentrations of 8, 12, and 16 dS/m and the second factor is Trichoderma as T. aureoviride (T148-2, T189-4) and T. virens (T145, T133-1) as well as the control. The results show that under the influence of salinity, a significant decrease in growth traits takes place. At the highest salinity level, the average dry weight of roots and shoots is 50% and 72%, respectively. For stem diameter and seedling height, a 20% decrease is observed compared to the control. However, inoculation with Trichoderma improves these traits, resulting in a 1.6-fold increase in root dry weight (T142-8), a 2.7-fold increase in shoot dry weight (T133-1), and a 1.3-fold increase in seedling height (T189-4) in comparison to the control. The highest diameter increase could be observed in T142-8 strain by 38%. Using Trichoderma leads to significant changes in sugar, sodium, potassium, and calcium content. The results of this study show that Trichoderma can be a suitable biological agent to increase tolerance at high levels of salinity stress and improve the growth traits of eggplant seedlings.

The use of methods to reduce energy consumption in greenhouses such as reduced heat losses, and improved efficiency of heating, cooling, and irrigation systems cancut energy consumption for the production of any crop to several times. The present research has designed and built an automated system for climate control of a rose greenhouse. This system is consisted of control and measurement stations. The control unit, itself, is consisted of a human-machine interface (HMI) device; while the measurement station is formed of one humidity, one light, and eight temperature sensors. Climate conditions of the greenhouse is received by the measurement station, there to be sent to the control one. Also, energy consumption in both systems are calculated and analyzed, too. The present research compares the impacts of the built automated system for climate control of greenhouse on the qualitative and quantitative traits of three cut-roses cultivars including 'Angelina', 'Samurai', and 'Red One' with the control system. Quality index and shoot weight of the cut-roses are improved under the automated system than the control. But there no difference could be found in traits of flowering stem length and number, stem diameter, number of lateral and blind shoots, internodes length, and vase-life, between the crops of two systems compared. The results also indicate a reduction in energy consumption under the automated climate management system than the control, equal to 12%. In sum, considering that the use of climate control system has improved the efficiency of energy consumption without having a negative impact on the quantitative and qualitative characteristics of the crop, it is recommended.

Drought stress is one of the limiting factors of agriculture in many parts of the world, especially Iran. Understanding the mechanism behind drought stress’ effect on physiological and biochemical processes of genotypes is very useful for selecting and breeding genotypes compatible with Iranian conditions. For this purpose, the present study has been conducted in 2018-2019 in the Biotechnology Research Institute of Shiraz University to investigate the effect of drought stress on physiological and biochemical characteristics of both years’ old pomegranate seedlings of Wonderful cultivar in greenhouse conditions. Irrigation has been carried out at four levels of 100% (control), 75%, 55%, and 35% of field capacity for 50 days. The experiment is based on a completely randomized design with three replications. The results show that drought stress has significantly increased carotenoids, flavonoids, malondialdehyde, and proline. The relative leaf water content, cell membrane stability and anthocyanins has decreased, though there has been no significant difference in chlorophyll and glycine betaine levels between drought treatments. Also, the hydrogen peroxide (81%) and activity of superoxide dismutase (480%), catalase (96%), and ascorbate peroxidase (96%) in 35% of field capacity significantly has increased. According to the results of this study, especially the increase in proline and antioxidant enzymes under drought stress, tolerance mechanisms in pomegranate cultivar Wonderful can be associated with active osmotic regulation and active enzymatic antioxidant system.

In order to investigate the yield and yield components of Guar (Cyamopsis tetragonoloba L.) genotypes to supplementary irrigation in rainfed conditions, a two-year study has been conducted in the form of split strip plots based on a randomized complete block design with three replications at stations Shirvan, Kohnehkand and Mohammadabad research stations in North Khorasan during 2019-2020 cropping years. The main factor includes irrigation levels at three levels: rainfed, two irrigations (after planting and filling seed time), and three irrigations (after planting, pod formation and filling seed), with the second factor being guar genotypes at four levels. The three Genotypes include RGC-1077, RGC-1036, RGC-1025, and Chabahar local population. Results of the combined analysis show that there has been no significant difference between genotype except in the number of days to flowering. On the other hand, the effect of supplementary irrigation treatment on yield characteristics compared to rainfed conditions is significant, though there has not been any significant difference between two and three times of supplementary irrigation. Guar seed yield in the first and second years in the Ashkhaneh region (750.5 and 219.1 kg.ha-1) outperforms Bojnourd and Shirvan. The highest grain yield (590 kg.ha-1) is obtained in the first year from double irrigation and in the second year (271.51 kg.ha-1) from three irrigations. Among the experimental genotypes, the highest grain yield belongs to the RGC-1025 genotype. In general, guar culture of the RGC-1025 genotype can be recommended in the Ashkhaneh area..