جستجوی مقالات مرتبط با کلیدواژه "stomatal conductance" در نشریات گروه "زراعت"

Rice is one of the most important agricultural products in the world, and it has the second place in terms of annual production after wheat. Cultivation of rice in most regions of the world is done in the form of transplanting, but the long period of preparing transplant and sometimes high mortality of transplants in the main field, high water consumption, the impossibility of direct use of transplanting machines in heavy soil textures and high labor costs have caused it is an undeniable necessity to find suitable methods of planting rice with the aim of reducing the inhibiting effects of these factors especially reducing water consumption and achieving optimal performance. On the other hand, choosing the suitable planting date is another important agricultural management to achieve optimal crop performance. In this experiment, the effect of different land preparation (planting bed) methods and different transplanting dates were investigated on the physiological characteristics and yield of three rice varieties in Shavor region, Khuzestan province, Iran. The purpose of this experiment was to determine the role of planting date and planting bed on the growth and development aspects of rice transplants and their interations on reducing the inhibiting effects of production factors.

This experiment was carried out in the form of split split plots based on randomized complete block design with three replications in the research field of Shavor Research Station, Khuzestan province, Iran, in 2021 and 2022. The experimental factors were land preparation (planting bed) methods in four levels including puddling, flat with field capacity, flat with dry soil and raised bed in the ridge with dry soil as the main factor, transplanting date in three levels including 2, 12 and 23 June as the sub-factor, and rice variety in three levels including Champa, Anbori Germez Paboland and Daniyal as the sub-sub-factor. To prepare the planting beds (puddling, flat with field capacity and flat with dry soil), the soil was leveled by leveler after plowing and disking, and to prepare the raised bed in the ridge, the ridges (with a width of 50 cm and a height of 20 cm) were created by a ditcher after plowing, disking and leveling. The measured traits in this study were paddy yield, biological yield, harvest index, chlorophyll index, canopy temperature and stomatal conductance.

The results of combined analysis of variance showed that the effect of planting bed, planting date and variety as well as their interactions on rice yield were statistically significant. The results of the comparison of two years means showed that the highest grain yield was belonged to flat bed with dry soil on the planting date of 2 June in Anbori Germez Paboland variety (5.68 ton.ha-1), and the highest biological yield was obtained from the flat bed with field capacity on the planting date of 23 June in Anbori Germez Paboland variety (13.63 ton.ha-1). Also, the highest harvest index (51.71 %) and the best canopy temperature at the stage of panicle emergence (32.22 °C) was observed in the treatment of flat bed with dry soil on the planting date of 23 June in Champa variety.

According to the results of grain yield as the most important goal of rice planting, it seems that by cultivation of the local variety “Anbori Germez Paboland” on the flat bed at 2 June through the provision of environmental conditions (non-implementation of puddling and preventing negative effects on plant growth), and a suitable temperature (preventing the occurrence of stress in the flowering and seeding stage), can obtain a high grain yield.

High temperature has negative effects on olive physiology, especially flowering, fruit growth and oil production. To identify olive cultivars/genotypes tolerant to heat stress, 12 olive cultivars and genotypes with four temperature treatments T1: (34 ± 1.5 ˚C), T2: (37 ± 1.5 ˚C), T3: (40 ± 1.5˚C) and T4: (43 ± 1.5 ˚C) were evaluated at Tarom olive research station, Iran, in 2016. The experiment was conducted as factorial arrangement in randomized complete block design with three replications. The results showed that the photosynthesis rate and water use efficiency decreased with increasing temperature. The results showed that the highest photosynthesis rate was obtained in T1 with 11.84 μmol m-2 s-1 and the lowest in T4 with 4.87 μmol m-2 s-1. In T4 temperature treatment, cv. Manzanilla maintained more than 50% and cv. Amin 44% of their photosynthesis efficiency compared to T1 temperature treatment. The of cultivar temperature × treatment interaction effect showed that the highest photosynthesis rate in T1 was 17.42 and 17.25 μmol.m-2s-1 in cv. Amin and cv. Deira, respectively. At temperatures > 40° C, there was a sharp decrease in the stomatal conductance of the leaves. Cv. Arbequina and Ozine genotype had the highest and lowest water use efficiency with 2.63 and 1.84 mmolCO2 molH2O-1, respectively. Also, the highest water use efficiency was obtained in KH15 genotype and cv. Deira in T1 temperature treatment. Due to the considerable decrease in photosynthesis rate at temperatures above > 40 °C, olive cultivation in areas with hot summers will cause significant reduction in fruit yield and in fruit oil content. 

Oil rapeseed (Brassica napus L.) stands out as a precious oilseed plant cultivated globally, ranking as the third major source of oil production. The cultivation of this plant is expanding due to its notable nutritional and economic advantages. However, the arid and semi-arid climate of Iran poses a challenge to rapeseed cultivation, particularly with the occurrence of water deficit stress towards the end of the season. Various strategies are employed to mitigate the adverse effects of drought stress and enhance plant tolerance. One effective method involves the application of biological stimulants, such as amino acids. These compounds can stimulate plant growth and development, under optimal conditions and stress. Amino acids play direct and indirect roles in physiological metabolism, facilitating nutrient exchange and structural activities. This includes the augmentation of photosynthetic pigment concentration, enhancement of photosynthesis rate, and increased protein synthesis, particularly under stress conditions. In consideration of the significance of oil and the role of rapeseed in oil production, along with the challenges posed by drought stress during the reproductive growth stages of rapeseed, this study was conducted to examine the impact of foliar application of amino acids on the physiological parameters of oil rapeseed under conditions of irrigation interruption at the end of the season.

This experiment was conducted to investigate the effect of foliar spraying of amino acids on the physiological characteristics and chlorophyll fluorescence parameters and photosynthetic pigments of oil rapeseed under withholding irrigation at the end of the season (reproductive growth stage) as factorial design based on randomized complete blocks with three replications in the research farm of the Faculty of Agriculture of Tarbiat Modares University, during the 2022-2023 growing season. The investigated factors were three levels of irrigation (full irrigation during the season, withholding irrigation from 50% flowering stage, withholding irrigation from pod forming) and five levels of foliar spraying (no foliar spraying, zero foliar spraying (distilled water), one, two and three grams of amino acids per liter) in stem elongation, flower-bud emergence, and flowering stages. The experimental plots included four planting rows and three meters in length. In the field, one week after the last foliar spraying, photosynthetic and transpiration rates and various fluorescence parameters were measured using a portable gas exchange and Mini-PAM device, respectively. Moreover, pigments (including chlorophyll a, b and carotenoid) in the fresh plant samples were determined in the laboratory. After ensuring the normality of the residual of data, statistical analysis was performed using SAS software (version 4.9.) to compare the average data. The LSD test was used at the five percent level.

Physiological and biochemical traits were adversely impacted by water deficit stress, as evidenced by the withholding of irrigation. This stress condition significantly decreased various characteristics, including maximum photosystem efficiency, photosynthesis rate, stomatal conductance, transpiration rate, and levels of photosynthetic pigments. However, applying amino acids via foliar spray mitigated the adverse effects of drought stress. The results indicated that the photosynthesis rate, stomatal conductance, transpiration rate, intercellular CO2 concentration, intercellular CO2/ambient CO2 ratio, photosynthetic pigments (chlorophyll a, chlorophyll b, and carotenoids), and chlorophyll fluorescence parameters were significantly influenced by the interaction between drought stress and foliar application of amino acids.  The results indicated that the foliar application of two grams of amino acids per liter significantly increased various physiological parameters compared to the control group. Specifically, it resulted in a 22% enhancement in the photosynthesis rate, an 80% improvement in stomatal conductance, a 30% elevation in transpiration rate, a 40% rise in chlorophyll b, and a 27% increase in carotenoid levels. Conversely, the foliar spraying of one gram of amino acids per liter yielded the highest levels of chlorophyll a and the maximum quantum efficiency of photosystem II. These values were 20% and 5.5%, respectively, different from those observed in the control group. Also, the highest grain yield was obtained under withholding irrigation from 50% flowering stage (1440 kg ha-1), withholding irrigation from 50% flowering stage (2346 kg ha-1) and full irrigation during the season (4514 kg ha-1) with foliar application of 2 grams of amino acid per liter.

Based on the findings, the most favourable impact of foliar application of amino acids on the investigated traits was observed at a concentration of two grams per liter of water. Notably, the enhancement of these traits has a direct correlation with seed yield. Consequently, considering the substantial influence of these traits on the improvement of seed yield (22.4% and 61.4% under full irrigation and irrigation interruption conditions, respectively), the recommendation is to employ foliar spraying of two grams of amino acids per liter. This application is suggested to enhance rapeseed's physiological and biochemical characteristic across all three irrigation regimes, including full irrigation and interruption of irrigation from the flowering and budding stages.

Crop yields in tropical regions is threatened by high temperatures during reproductive phase which causes a severe change in physiological and biochemical behavior of the major crops (Salehi et al., 2023). A suitable sowing dates provide adequate growth and development for crops and altered sowing dates is beneficial for crop productivity as it helps the critical growth stages avoid high temperature stress. Manipulating the sowing date is one of the the most important management practices for improving crop yield and resource use efficiency (Srivastava et al., 2018). It has been reported that the highest grain and biological yield of safflower were observed on early sowing date, compared to late sowing dates (Sahu and Thakur., 2016)). Delay in sowing date causes shortening of the growing season and distance of the plant from suitable growing conditions. Cytokinins are effective in response to environmental stresses by triggering a complex signaling network (Verma et al., 2016). To further improve plant growth and production, exogenous cytokinin has been applied to enhance the heat stress tolerance of plants. Exogenous application of cytokinin reduced the inhibitory impact of heat stress on photosynthetic properties, and increased antioxidant system activity (Xu et al., 2010). Hence, the current study aimed to evaluate the effect of cytokinin foliar on morphophysiological traits and quantitative yield of sunflower cultivars in winter planting dates in Ahvaz conditions.

A field experiment carried out in a split plot factorial in randomized complete block design with three replications at the research farm of Shahid Chamran University of Ahvaz in 2022. Main plots consisted of two sowing dates; 3th February and 5th March (Normal and late sowing dates, respectively), and sub plot consisted of factorial arrangement of different concentrations of cytokinin (0 and 50 μm l-1, Kinetin), and sunflower cultivars (Progress, Lakomka, Shams, Oskar and Qasem). The cultivation was performed on 3th February as normal sowing date plants experienced optimum temperature during growth stages. On 5th March as late sowing date, the flowering and grain filling periods were exposed to severe heat stress at the end of growing season

Terminal heat stress in late sowing dates caused a significant decrease in in biological yield, grain yield, grain number per head, 1000-grain weight, oil yield, chlorophyll index, relative water content and stomatal conductance. There was a significant difference among cultivars in terms of all traits. Late sowing date was caused a significant reduction in grain yield of Lakomka, Progress, Shams, Oskar and Qasem cultivars by 32, 30, 32, 37 and 33%, respectively, compared to normal sowing date. It was equal to 1.1, 1.03, 1.1, 1.27 and 1.13% for each day of sowing delay, respectively. The concentration of 50 μm l-1 kinetin improved the studied traits in both sowing dates. In late sowing date, foliar application of cytokinin enhanced grain yield by 24, 29, 14, 25 and 21%, in Lakomka, Progress, Shams, Oskar and Qasem cultivars respectively, when compared to cytokinin-deficient plants. Lakomka and Progress had the highest grain and oil yield in both sowing dates. In optimum and late sowing dates; cytokinin application induced an increase in grain yield (by 11 and 24%, respectively) and oil yield (by 27and 34%, respectively) for Lakomka, when compared to cytokinin-deficient plants. Lakomka cultivar identified as the most tolerant to heat stress due to higher grain and oil yield in both sowing dates and both cytokinin levels compared with other cultivars.

We focused on foliar application of cytokinin on morphophysiological traits and quantitative yield of sunflower cultivars in response to terminal heat stress to highlight the function of cytokinin in heat stress response and it is potential to increase heat stress tolerance. It appears the delay in optimum sowing date leads to synchronize the plant's reproductive stages with a high temperature at the end of the season. The results of this study provides evidence that exogenous cytokinin (50 μm l-1) can be an effective strategy in improvement of heat tolerance of sunflower under terminal heat stress conditions in tropical regions such as Khuzestan.

One of the most important problems threatening agriculture is water deficit stress in many regions of the world. Water deficit stress could result in a decrease in yielding or death of a wide range of crops. In Iran, like other arid and semi-arid regions, forage quality and production have decreased due to the occurrence of frequent water stress. Restriction of water resources, especially in arid and semi-arid regions where agricultural systems depend on supplementary irrigation, has become the most important problem of fodder production. Persian clover (Trifolium resupinatum L.) is a forage legume cultivated in the temperate region of world; it is of great value for livestock feed, soil improvement, and reclaiming disturbed land because of its nitrogen-fixing capability. The purpose of this research, was evaluate the effect of water deficit stress on the physiological and qualitative traits of fodder of Persian clover.

An experiment was carried out during the 2016 and 2017 cropping seasons as a randomized complete block design at the Research Farm of Tarbiat Modares University. Experimental treatments included water deficit stress at four levels. The tested treatments included water deficit stress at four levels (irrigation after reaching the levels of 80, 60, 40 and 20% available moisture). Irrigation of all treatments was carried out at the level of 70% of available water until the start of stress in the final stages of vegetative growth of the second cut. To measure the effects of water deficit stress on physiological traits physiological indexes were recorded during the first 10 days of stress treatment, every day. The clovers were harvested at about 20-25% flowering stage. After drying, they were transferred to the laboratory to determine the quantitative and qualitative feed yield. Based on Bartlett's test results, the experiment's dependent variables had the same trend.

The results show that the irrigation regime had a significant effect on all traits. Irrigation treatments at 80 and 60% of available water had the highest dry matter yield, and delaying irrigation until 40 and 20% caused a 19% and 36% significant decrease in this trait. Also, stress at the level of 20% caused a 27% decrease in fodder protein, a 10% increase in acid detergent fiber and neutral detergent fiber, and finally, an 16% reducing relative feed value. Evaluation of physiological traits in the first ten days of the beginning of water stress showed a continuous increase in leaf temperature from 30.5 to 34 ˚C, and 49, 50, and 15% decrease in photosynthesis rate, stomatal conductance, and SPAD index, respectively. It Also reduces the concentration of chlorophyll a and b 25 and 40 percent. The return of increased leaf temperature and reduced stomatal conductance due to the discharge of 80% moisture was fast to the initial level, but other traits slowly approached the value before the stress. It seems that returning to initial values at levels of 80 and 60 is easily possible for the plant, but with the increase in the intensity of stress, the damage of dehydration is slowly compensated.

The experiment results showed that the photosynthesis rate and other physiological traits of Persian clover significantly react to the soil's decreased available water. In most physiological traits, irrigation after the available soil moisture reached 60% caused a relatively quick return to the initial value. There was no significant difference in fodder yield in the 80% and 60% irrigation treatments. When the available soil moisture reached 40%, the physiological traits showed a greater decrease than before. It seems that some damages to physiological traits are irreparable to such an extent that they eventually lead to a drop in yield or a decrease in the quality of Persian clover fodder. Finally, it is not necessary for clover irrigation at levels of more than 60% of available water, taking into account the more quality of forage in the level of 60% (about 1.5% of insoluble fiber, and 11% feed value), considering the water conditions of the country.

Drought is one of the most important factors limiting crop production. ‎Several methods have been proposed to increase the resistance of crops against water limitation. In this ‎regard, the use of vermicompost and silicon can improve the performance of crop plants under stress ‎conditions. Considering the above fact, thr present study was undertaken to evaluate the effects of ‎nanosilicon and vermicompost application on grain yield and the trend of changes some physiological ‎traits (i.e, chlorophyll index, nitrogen index, relative water content, leaf electrical conductivity and ‎stomatal conductivity) of rye in different irrigation regimes.‎ a factorial experiment based on randomized complete block design with three ‎replications was conducted under the research greenhouse conditions in 2023. Treatments were various ‎irrigation regimes (normal irrigation as control, irrigation withholding at 50% of booting and heading ‎stages as severe and moderate water limitation, respectively), application of nanosilicon and ‎vermicompost at four levels (no application as control, application of nanosilicon, vermicompost, both ‎application vermicompost and nanosilicon). Vermicompost was prepared from Gilda corporation and ‎silicon from Pishgaman Nanomaterials Company. Nano silicon was with the average of particle size of ‎less than 30 nm. Foliar application of Si was done in stages of tillering and stem elongation (BBCH 21 ‎and 30, respectively).‎‏ ‏Two weeks after irrigation withholding in booting stage, some biochemical and ‎physiological traits were measured on the flag leaf. The trend of changes some traits such as chlorophyll ‎index, nitrogen index, relative water content, leaf electrical conductivity and stomatal conductivity were ‎measured at time intervals every four days from 135 to 150 days after planting.‎‏ ‏Analysis of variance was ‎done by software package SAS v9.12. The main effects and interactions were compared by LSD test at the ‎‎0.05 the probability level, using the SAS version 9.1. ‎ study of the trend of changes some physiological traits showed that in 151 days after plantingunder irrigation withholding at of booting conditions, application of vermicompost and nano silicon ‎increased chlorophyll index (47.9%), nitrogen index (47.6%), relative content of flag leaf (30.2 %), ‎stomatal conductance (12.8%), root weight and volume (22.3 and 28.3%, respectively), plant height ‎‎(32.5%), spike length (32.2%), the number of grains per spike (40.2 %) and grain yield (7.3%) as ‎compared to no application of nano silicon and vermicompost at the same level from irrigation levels. ‎Also, under irrigation withholding at of booting stage conditions, no application of nano silicon and ‎vermicompost increased electrical conductivity (13.8%), hydrogen peroxide content (26.7%) and ‎malondialdehyde (9.8%) as compared to application of nano silicon and vermicompost at the same level ‎from irrigation levels.‎ Therefore, with considering of the results of this study, it can be stated that, applying ‎nano silicon and vermicompost were able to compensate part of the yield reduction caused by water ‎limitation by improving some physiological traits of rye.‎

Quinoa (Chenopodium quinoa L.) is a dicotyledonous, allotetraploid, three-carbon, annual, optional salt-loving plant and is native to South America and the Andean highlands. The growth period of the plant varies between 70 and 240 days depending on the cultivated area. The main product of this plant is the seed, which has a high nutritional value in terms of protein, amino acid balance, unsaturated fat, vitamins, and minerals. Like other plants, quinoa faces various environmental stresses during its growth period, and its growth and yield are a function of environmental factors and their mutual effects. The occurrence of high temperatures during the sensitive stages of plant growth, such as flowering and seed formation, may cause a significant decrease in quinoa yield, and high temperature has been cited as one of the most important challenges for the cultivation and expansion of quinoa in the world. Salicylic acid acts as a signal molecule and plays an important role in regulating growth and development processes in plants under environmental stress. Salicylic acid increases the content of relative humidity, accumulation of dry matter, and the amount of chlorophyll.

The objective of this research is to assess the physiological responses of quinoa cultivars to varying planting dates and the impact of foliar application of salicylic acid in mitigating the adverse effects of end-of-season heat stress during the 2021-2022 crop year. The study was conducted at the research farm of the Faculty of Agriculture, Shahid Chamran University of Ahvaz, using a split-split plot design within a randomized complete block framework, with three replications. In this experiment, three factors a) planting date including October 12, November 11, and December 11, and b) foliar application of salicylic acid in the two stages of budding and the beginning of flowering including non-application, 1.5 mM and 3 mM and c) Quinoa cultivars including Titicaca, Giza, Q12 and Redcarin were investigated.

The effect of investigated factors such as planting date, salicylic acid, and variety on different traits had statistically significant differences. The results showed that the maximum amount of stomatal conductance and the relative content of leaf water belonged to the date of October 12. The highest biological yield and seed yield were observed under conditions of application of 1.5 and 3 mM salicylic acid, respectively. Probably, salicylic acid has increased the growth and accumulation of dry matter by improving carbon fixation, synthesis of metabolites, and maintaining the water status of plant tissues. Based on the results of the comparison of the mean of the three-way interaction, the maximum amount of biological yield and seed as the most important goals of quinoa plant cultivation, respectively, in the treatment of not using salicylic acid in the Redcarin cultivar on the planting date of December 11 and the application of 3 mM salicylic acid was obtained in the variety Redcarin on the planting date of October 12. The highest rate of net assimilation and the growth rate of the product belonged to the treatments of no application of salicylic acid in the Redcarin cultivar on December 11 and no application of salicylic acid in the Giza cultivar on October 12, respectively. The treatment of not using salicylic acid in the Redcarin variety on the planting date of October 12 was also able to achieve a high harvest index.

 According to the obtained results, it seems that to achieve a high seed yield of quinoa, it is possible to benefit from the treatment of 3 mM salicylic acid in the Redcarin variety on the planting date of October 12.

To evaluate the biomass, physiological traits, and advantages of maize-amaranth intercropping in the cultivation in barley residues and different levels of nitrogen in 2020-2021, an experiment was implemented in the research farm of Tarbiat Modares University. This study was conducted as a split-split plot experiment in a randomized complete block design with three replications. The studied factors included: 1- Cultivation in two levels (cultivation in barley residues and cultivation without barley residues) as the main plots, 2- the type of cultivation in two levels (monoculture and intercropping) as subplots, 3- different levels of nitrogen (N) in four levels (0, 100, 200, and 300 kg N ha-1 for maize and 0, 40, 80, and 120 kg N ha-1 for amaranth) as sub-subplots. The results showed that the highest total dry weight of amaranth was observed in the treatment of 80 kg N ha-1 of nitrogen application in the conditions of amaranth monoculture and without the use of barley residues with a production of 8031 kg ha-1. The highest dry weight of maize (11187 kg ha-1) was obtained from the treatment of maize monoculture in barley residues with the application of 300 kg N ha-1. The highest photosynthesis rate of amaranth was observed in the treatments of 40 kg N ha-1 application in the conditions of monoculture without barley residues and N fertilizer, and application of 40 kg N ha-1 in the conditions of intercropping with maize and without barley residues. In addition, the results showed that the highest maize photosynthesis rate was achieved with the application of 300 kg N ha-1, and the photosynthesis rate also significantly decreased with the reduction of nitrogen application. Land equivalent ratio (LER) showed an increase of 30% in the intercropping of maize and amaranth in the cultivation of barley residues with the application of 100 kg N ha-1 for maize and 40 kg N ha-1 for amaranth, which indicated the advantage of intercropping. According to the results of this research, if the goal was to produce amaranth, barley residues should not be used, but in maize cultivation, the use of barley residues is recommended. Also, the use of 40 and 300 kg N ha-1 is recommended to increase biomass of amaranth and maize, respectively.

Water limitation is one of the most important abiotic stresses that can decrease growth and yield of rye (Secale cereal L.). Several strategies have been suggested in order to improve yield of rye under water limitation conditiond, among them application of mycorrhiza, nanoparticles of iron and silicon play a key role in yield improvement. In this regard, in order to study the effects of mycorrhiza, nanoparticles of iron and silicon on some physiological and biochemical traits of rye (Secale cereal L.) under withholding irrigation conditions, an experimental as factorial was conducted based on randomized complete block design with three replications in research greenhouse of Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili during 2022. Experimental factors were included irrigation in three levels (full irrigation as control, withholding irrigation at 50% of heading and booting stages), mycorrhiza application at two levels (no application as control, application of mycorrhiza), nano iron-silicon oxide foliar application at four levels (foliar application with water as control, nano iron oxide foliar application, nano silicon, both application nano iron-silicon oxide). The results showed that withholding irrigation decreased relative water content and stomatal conductance in all of sampling stages, but application of nanoparticles and mycorrhiza were able to compensate of part of this reduction. Also, both application nanoparticle and mycorrhiza under withholding irrigation at booting stage decreased malondialdehyde and hydrogen peroxide contents (58.87 and 36.04% respectively) in comparison with no application of nanoparticle and mycorrhiza in the same irrigation level. But, it increased the activity of catalase, peroxidase and polyphenol oxidase enzymes (34.67, 32.14 and 32.18% respectively), proline and soluble sugars contents (38.01 and 28.33% respectively) in comparison with no application of mycorrhiza and nano iron-silicon oxide in the same irrigation level. Maximum of grain yield (2.76 g.per plant) was obtained at both application nanoparticle and mycorrhiza in full irrigation, which increased grain yield of 45.2% in comparison with no application of mycorrhiza and nano iron-silicon oxide under withholding irrigation at booting stages. Based on the results of this study, it can be suggested that under withholding irrigation conditions, application of nanoparticles and mycorrhiza can increase grain yield of rye by improving the physiological and biochemical traits.

In order to effect of potassium nano chelate on physiological and yield characteristics of barley in irrigation cut-off conditions, this research was done as split plot in randomized complete blocks design with three replications. Main treatment consisted: full irrigation, no irrigation at the beginning of stem elongation, and no irrigation at the pollination stage and sub treatment consisted: no foliar application (control), 35 mg.L-1 and 65 mg.L-1 potassium nano chelate. results showed that the effect of deficit irrigation cut-off and potassium nano-chelate on number of spikes, number of seeds per spike, weight of 1000 seeds, grain yield, stomatal conductance, canopy temperature and relative water content leaf were statistically significant at 1% level of probability. Interaction irrigation cut-off and potassium nano-chelate number of spikes, weight of 1000 seeds, in canopy temperature and relative water content leaf were significant at 1% probability and stomatal conductance at 5% probability level. The highest grain yield was in full irrigation (control) (5308 kg.ha-1) and 65 mg.L-1 potassium nano-chelate (4854.9 kg.ha-1) and the lowest was in irrigation at anthesis (3169.4 kg.ha-1) and no foliar application (control) (3588 kg.ha-1). the maximum relative water content of leaf was in complete irrigation (control) and foliar application of 65 mg.L-1 potassium nano-fertilizer (73.13%) and the minimum was in non-irrigation at anthesis and non-foliar application of potassium nano-fertilizer (35.99%). maximum stomatal coductance was in complete irrigation (control) and foliar application of 65 mg.L-1 potassium nano-fertilizer (185.87 mlmol.m-2s-1) and the minimum was in non-irrigation at anthesis and non-foliar application of potassium nano-fertilizer (47.99 mlmol.m-2s-1). as a result, foliar application of 65 mg.L-1 potassium nano-fertilizer at different irrigation cut-off periods cause improves grain yield and leaf water in comparison to control (no foliar application) and is recommended.

With the aim of evaluating the effects of salicylic acid and brassinosteroid application on some physiological traits and arsenic accumulation in spinach under arsenic stress conditions, an experiment was conducted in a factorial experiment in the form of a randomized complete block design with four replications in the year 2022 in the Nutrition Research Center, Department of Food Hygiene and Quality Control, School of Nutrition and Food Sciences, Shiraz University of Medical Sciences, Iran. The experimental factors included salicylic acid (0, 0.5, and 0.75 mM), brassinosteroid (0, 0.5, and 0.75 µM), and arsenic stress (0, 50, and 100 µM). Arsenic stress, especially at 100 µM, reduced the net photosynthetic rate, transpiration rate, stomatal conductance of spinach leaves and biomass. Arsenic stress increased the concentration of malondialdehyde, hydrogen peroxide, osmolytes, as well as antioxidant enzymes activities in spinach plants. Application of brassinosteroid and salicylic acid significantly increased activities of antioxidant enzymes (peroxidase, ascorbate peroxidase, and superoxide dismutase), osmolytes accumulation (carbohydrates and proline) and spinach biomass; in contrast, application of brassinosteroid and salicylic acid decreased the concentration of malondialdehyde and hydrogen peroxide in spinach plants under arsenic stress conditions. Arsenic accumulation was higher in spinach roots than in leaves. Under 100 µM arsenic stress, the application of different concentrations of salicylic acid and brassinosteroid, individually and in combination, significantly reduced arsenic accumulation in spinach, with the highest positive effect being observed in the treatment of 0.75 mM salicylic acid + 0.75 µM brassinosteroid. In conclusion, brassinosteroid and salicylic acid application increased the tolerance of spinach plants against arsenic stress by improving gas exchange, activity of antioxidant enzymes, accumulation of osmolytes, stability of the membranes, and as a result plant biomass; the positive effects of brassinosteroid and salicylic acid together were greater than that of brassinosteroid or salicylic acid applied separately.

Sunflower, one of the primary oilseed crops worldwide, is cultivated extensively due to its suitability for agricultural needs, high oil yield, and nutritional and medicinal value. However, drought remains the most critical limiting factor affecting sunflower productivity. In arid and semi-arid regions, the intensity of drought stress is predicted to increase in the future. Unfortunately, severe drought stress leads to significant reductions in both seed and oil production. While sunflower is moderately drought-tolerant, understanding the physiological and agronomic aspects of drought stress is crucial for sustainable management. Given that water, scarcity poses a significant threat to crop productivity and environmental resources are diminishing, effective irrigation management under water scarcity is becoming increasingly important.

In order to study the effects of deficit irrigation on grain yield and physiological traits of six sunflower cultivars, a field experiment was carried out in a split-plot arrangement based on randomized complete block design with three replications in 2019-2020 growing season. The experimental site was located in the research farm of the Safiabad Agricultural and Natural Resources Research and Education Center. Main plots consisted of three irrigation regimes including; control, moderate, and severe deficit irrigation (50, 70, and 90% of available moisture, respectively), and sub plots consisted of six sunflower cultivars including; Oscar, Felix, Shakira, Savana, Labad and Monaliza.

Different levels of deficit irrigation differently caused a significant reduction in stomatal conductance, photosynthetic rate, chlorophyll index, relative water content, grain yield, grain number per head, grain weight per head, and oil yield, when compared to control. Oscar cultivar with the highest stomatal conductance, photosynthetic rate, and chlorophyll index, produced the highest economic oil and grain yield while the Shakira cultivar showed the lowest grain yield values in different levels of deficit irrigation. Oscar in 50% of field capacity and Shakira in 90% of field capacity showed the highest and lowest grain yield values (5.34 and 2.67 ton ha-1, respectively). Labad maintained the highest grain yield in 70 and 90% of field capacity relative to the control (4.41 and 4.28 ton ha-1, respectively). It seems that deficit irrigation leads to a significant reduction in grain yield by reducing the reproductive stage, producing fewer seeds, and the impossibility of transferring assimilates to fill the grains. Moreover, the reduction of oil percentage is probably due to the acceleration of achene ripening, giving the plant a chance to escape from drought, because carbohydrates first accumulate in the achenes and then turn into oil or any other substance. Photosynthetic rate, stomatal conductance, light absorption, relative water content, leaf area index, chlorophyll index, and transpiration rate decreased by 49, 25, 28, 26, 48, 22 and 78%, respectively in severe deficit irrigation, while water use efficiency and canopy temperature increased by 58 and 16 % respectively. 

Various levels of deficit irrigation exerted an influence on the physiological characteristics and grain yield of sunflower cultivars. The extent of water scarcity emerged as a significant factor shaping the cultivar responses to deficit irrigation. Felix and Labad exhibited higher oil yield and are thus recommended for cultivation in Dezful and analogous regions, owing to their superior grain yield and ability to sustain grain yield under deficit irrigation conditions.

Drought is one of the major environmental stress induced by global climate change that adversely affects the growth and development of plants and causes significant yield losses in the oil seed crop, safflower. Drought stress adversely impacts growth and productivity with various physiological and biochemical processes such as stomatal conductance, photosynthesis, chlorophyll content, carbohydrate metabolism, lipid peroxidation, and antioxidant defense system. As, the water resources used for irrigated agriculture are decreasing in many agricultural regions of the world, therefore, irrigation management under water scarcity is increasingly important. Various deficit irrigation management strategies have been developed in different agroclimatic regions to improve crop performance under water deficit conditions. However, It is very important to develop crop management strategies that make plants suited for stressful environmental conditions

In order to study of deficit irrigation management on physiological and biochemical traits of two safflower cultivars, a field experiment was carried out in a split-plot arrangement in a randomized complete block design with three replications. The experimental site (32° 22' N, 48° 07' E), was located at Shahid Chamran University of Ahvaz, with a subtropical hot desert climate. Main plots consisted of four irrigation regimes including; control (irrigation treatments: 80%, 80%, 80%, and 80% of field capacity), mild (irrigation treatments: 60%, 80%, 80%, and 40% of field capacity), moderate (irrigation treatments: 60%, 60%, 60%, and6% of field capacity) and severe (irrigation treatments: 40%, 60%, 60%, and 60% of field capacity), and sub-plots consisted of two sunflower cultivars including; Padideh and Goldasht. Irrigation treatments were applied at stem elongation, branching, flowering, and grain-filling stages.

Deficit irrigation caused a significant reduction in stomatal conductance, photosynthetic rate, chlorophyll index, grain, and oil yield, but increased catalase and peroxidase enzyme activities, carbohydrate and malondialdehyde concentrations. Goldasht cv. with the highest stomatal conductance, photosynthetic rate, chlorophyll index, catalase, and peroxidase enzyme activities, carbohydrates concentrations, and with the lowest malondialdehyde concentrations and oil percentage had the highest economic oil and grain yield and it is recommended in a water-limited condition. The highest levels of antioxidant enzyme activity and lowest malondialdehyde content under water deficit conditions may provide better drought tolerance in this cultivar. The oil yield of both cultivars significantly decreased under moderate and severe heat stress by 31, 43, and 63%, respectively, when compared to the control. Goldasht cv. with a higher grain yield showed a higher oil yield.

Different irrigation regimes applied at different growth stages differently influenced the physiological and biochemical characteristics of safflower cultivars. The developmental stage and severity of water deficiency played an important role in cultivar responses to deficit irrigation regimes. Totally, a moderate deficit regime led to a 43% decrease in oil yield, but by saving about 40% of available water, this treatment is recommended as a suitable strategy for water management to reduce water use in this area.

Deficit irrigation is a water management strategy that reduces water use to the drought sensitive growth stages. In order to study of different deficit irrigation regimes on photosynthetic, morpho-physiological and yield traits of two safflower cultivars, a field experiment was carried out in a split plot arrangement in randomized complete block design with three replications in the research farm of Shahid Chamran University of Ahvaz in 2017-2018. Main plots consisted of four irrigation regimes including; Control (irrigation treatments: 80%, 80%, 80%, and 80% of field capacity), mild deficit irrigation (irrigation treatments: 60%, 80%, 80%, and 40% of field capacity),  moderate deficit irrigation (irrigation treatments: 60%, 60%, 60%, and 60% of field capacity) and severe deficit irrigation (irrigation treatments: 40%, 60%, 60%, and 60% of field capacity), and sub plots consisted of two safflower cultivars including; Padideh and Goldasht. Deficit irrigation treatments were applied at stem elongation, branching, flowering, and grain-filling stages. There was a significant difference between cultivars in terms of most traits and irrigation regimes differently caused a significant reduction in stomatal conductance, photosynthetic rate, number of head per plant, number of grain per head, number of grain per plant, 1000 grain weight, head diameter, height of first secondary branch, plant height, number of secondary branch per plant, biomass yield, harvest index, and grain and oil yield. The grain yield of the both cultivars significantly reduced under mild, moderate and severe water-deficit stresses by 26, 39 and 63%, respectively, relative to the control. The reductions were 31, 43 and 63%, respectively, compared to the control in oil yield. Goldasht showed higher oil yied due to it’s higher grain yield compared to Padideh. Totally, moderate deficit regime as a suitable strategy  of water management to reduce water use and Goldasht cultivar cultivation is defined in this area.

In order to evaluate the effect of putrescine, vermicompost and mycorrhiza on yield, activity of antioxidant enzymes and some physiological traits of triticale in different irrigation regimes, an experiment was conducted as factorial based on randomized complete block design with three replications at the Research Farm of University of Mohaghegh Ardabil, northwest of Iran in 2020. The experimental factors included irrigation in three levels (full irrigation as control; irrigation withholding at 50% of heading, and irrigation withholding at booting stage), application of bio-organic fertilizers in four levels (no application as control, application of vermicompost, mycorrhiza, and simultaneous application of vermicompost and mycorrhiza), foliar application of putrescine in three levels (foliar application with water as control, foliar application of 0.4 and 0.8 mM). The results showed that the irrigation withholding in booting stage with application of mycorrhiza, vermicompost and foliar application of 0.8 mM putrescine increased activity of catalase, peroxidase and polyphenol oxidase enzymes compared with no application of bio-organic fertilizers and putrescine at the same irrigation level. Evaluation of some physiological traits showed that at 242 days after planting, the simultaneous application of vermicompost and mycorrhiza and foliar application of 0.8 mM putrescine under irrigation withholding in booting stage conditions increased the relative water content (39.1%), chlorophyll a content (49.3%), chlorophyll index (37.2%), stomatal conductance (32.1%), variable fluorescence (84.9%), maximum fluorescence (45.1%), and quantum efficiency of photosystem II (27.6%) in comparison with no application of biofertilizers and putrescine at the same irrigation level. Moreover, application of vermicompost and mycorrhiza and foliar application of 0.8 mM putrescine at full irrigation conditions decreased hydrogen peroxide (29.2%), while increased grain yield (39.6%) in comparison with no application of biofertilizers and putrescine under irrigation withholding in booting stage. It seems that the simultaneous application of mycorrhiza and vermicompost and foliar application of putrescine can increase the grain yield of triticale under water limitation conditions due to improvement of antioxidant enzymes activity and some physiological traits.

Covering a staggering 215 million hectares, wheat stands as the world's most extensively cultivated crop plant. Just like its botanical counterparts, wheat operates as an obligate aerobic organism, implying its reliance on absorbing oxygen from the surrounding environment to facilitate growth, proliferation, and the successful completion of its life cycle. Annual instances of waterlogging stress inflict harm upon wheat crops, attributed to inadequate irrigation practices, subpar drainage systems, uneven field leveling, elevated groundwater levels, the presence of unyielding impermeable layers, and bouts of intense, abrupt rainfall. This adverse impact is progressively escalating, potentially influenced by the ongoing shifts in climate patterns. Consequently, the adoption of resilient cultivars and the genetic enhancement of bread wheat assume critical importance. These strategies are aimed at augmenting the wheat's capacity to effectively cope with waterlogging stress, aligning it with the mounting demands of a burgeoning global population.To achieve these goals, it is necessary to understand the factors causing waterlogging stress damage in wheat and to know the mechanisms of tolerance in this plant. The survival of root terminal meristem cells under waterlogging stress conditions is very limited, and their ability to grow again after removing the stress is also restricted. Waterlogging stress leads to the death of primary roots and reduced growth of lateral roots in wheat. However, there is variation among wheat cultivars concerning these traits. Reduced access to oxygen hampers root growth and nutrient absorption, including nitrogen. Consequently, photosynthesis and carbohydrate availability decrease, further restricting root growth.

An outdoor pot experiment was conducted to investigate the effect of waterlogging stress on shoot and root dry matter, as well as some physiological characteristics. The experiment followed a split-plot design based on randomized complete blocks with three replications. The stress was applied at the three-leaf stage, and three control levels were used: no waterlogging stress, mild stress (48 hours of waterlogging stress), and severe stress (120 hours of waterlogging stress) as the main factors. Cultivars and genotypes were also included as secondary factors.During the stress period, the water level was maintained at approximately 5 cm above the soil level. The cultivation took place outdoors in plastic pots. Data analysis was performed using SAS software, and graphs were generated using Excel software. Comparisons between treatments were based on the standard error. After testing different models, the linear regression model was ultimately employed.

Mild and severe waterlogging stress resulted in a significant decrease in shoot dry matter of 14.06% and 38.37%, respectively, across all cultivars and genotypes. Different cultivars and genotypes exhibited varying responses to waterlogging stress. To further understand the reasons for these differences, among the 21 cultivars and genotypes, Mehrgan and Sarang cultivars, as well as ms 93-16 and ms 93-6 genotypes, were selected due to their contrasting tolerance levels and yield potential. These selected cultivars and genotypes were studied to analyze specific root traits.Amidst severe waterlogging stress, a significant 38% reduction in root dry matter and a corresponding 29% decrease in root volume were recorded when compared to stress-free conditions. This closely mirrored the decline evident in shoot dry matter. Evaluation of the susceptibility index during the three-leaf stage unveiled that sole resilience was exhibited by the Aflak cultivar. In contrast, the remaining cultivars and genotypes were stratified into semi-tolerant and semi-susceptible categories.Notably, regression analysis underscored that even brief periods of waterlogging stress ushered in a reduction in dry matter. Furthermore, the elongation of the waterlogging duration magnified this decrease in dry matter, thereby mitigating the disparities across various cultivars and genotypes.

In general, cultivars that were able to sustain higher levels of photosynthetic activity during waterlogging stress demonstrated a lower percentage decrease in dry matter. Although the Mehrgan cultivar experienced a significant reduction in dry matter yield and fell into the semi-sensitive group, it consistently exhibited significantly higher dry matter yield compared to other cultivars and genotypes across all treatments.

This experiment was conducted to evaluate the effect of micronutrients on leaf phenol content and yield of SC704 corn hybrid in water deficit condition during two years (2018-2019 and 2019-2020) in Shahid Salemi farm of Ahvaz. The experiment was conducted as split-split plots in a randomized complete block design with three replications. Main plots included water deficit stress at three levels (complete irrigation, cut-off irrigation at vegetative growth stage (12-14 leaf stage), and cut-off irrigation at early seed growth stage (13-15 days after pollination), and sub-plots included sulfate foliar application zinc sulfate at three concentrations (0, 5, and 10 g/L) and sub-subplots contained foliar solution of iron sulfate at three concentrations (0, 3, and 6 g/L). The results of this study showed that foliar application of zinc sulfate in the cut-off irrigation conditions in the vegetative growth stage and in the beginning of the seed growth stage led to a significant increase in stomatal conductivity and leaf phenol content. The lowest leaf proline was obtained under complete irrigation conditions without iron sulfate solution. The highest yield of ear was obtained in complete irrigation with 6 g/L concentration of FeSO4 (9135.66 kg/ha), which increased by 25.1% compared to non-spray at this irrigation level. In general, unfavorable changes in physiological and functional indices of SC704 corn hybrid under the cut-off irrigation at the reproductive growth stage were more than the vegetative growth stage, and the application of zinc sulfate and iron sulfate in optimal concentration led to reduce the damage and adverse effects of water stress in these growth stages.

Soil salinity is one of the major environmental stresses which reduces the growth and yield of crops by affecting wide spectra of physiological and biochemical processes in plants. In this study, effect of foliar application of melatonin levels (0 and 200 μM) under salt levls (0, 30, 60, 90 and 120 mM NaCl) on sour orange rootstock was investigated. The experiment was carried-out as factorial arrangements in completely randomized design with four replications in 2020-21 at the research farm of Sari Agricultural Sciences and Natural Resources University, Sari, Iran. The results showed that most of morphological and physiological characteristics were affected by salinity and foliar application of melatonin. Salinity × foliar application of melatonin interaction effect was significant on most of studied traits including leaf length, leaf width, flush number, flush length, root length, leaf moisture and dry matter contents of leaf, ion leakage, stomatal conductance, transpiration rate, of assimilation rate, vapor pressure deficit and photosynthetic quantum yield. Foliar application of melatonin increased leaf moisture content, flush number, assimilation rate, stomatal conductance and photosynthesis quantum yield, while leaf ion leakage decreased. The highest photosynthetic quantum yield was recorded in 200 µM melatonin and salinity free treatment. Foliar application of melatonin under salinity stress conditions improved most of the physiological parameters. Foliar application of melatonin at different salinity levels caused significant increases in length and width of flush leaves compared to the control. Overall, the results of this study showed that foliar application of melatonin reduced negative effects of salinity stress on growth and physiology of sour orange rootstock, therefore, it can be considered as an effective approach to mitigate the adverse effect of soil and water salinity on sour orange rootstock.

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.

The effect of salinity stress on the quantity and quality of crop production highlights the importance of managing and reducing the damage caused by this stress factor in agriculture. Increasing soil salinity and decreasing fertility of arable lands is one of the major problems in saline areas. Cultivation of salt-tolerant crops which can increase soil fertility could be effective in the sustainable production of these lands. Studying photosynthesis and its related factors could provide appropriate physiological views in understanding plant behavior against salinity stress. The present study was conducted to assess the salinity tolerance of chickpea genotypes for cultivation in saline areas.

To evaluate the effects of salinity stress on photosynthetic criteria and yield of chickpeas, an experiment was conducted in 2018 at the research farm of the faculty of agriculture, Ferdowsi University of Mashhad, Mashhad, Iran. The experiment was arranged as a split plot based on a randomized complete block design with three replications. Experimental factors consisted of salinity levels (0.5 and 8 dS.m-1) as the main plot and chickpea genotype (17 kabuli-type genotypes) as the subplot. Seeds were provided from the Mashhad chickpea collection of the Center for Plant Sciences, Ferdowsi University of Mashhad, Mashhad, Iran. Seeds were planted on March 11th and complementary irrigation was done in three growth stages of pre-flowering, flowering, and pod-filling. Sodium chloride was used to prepare saline solutions and the irrigation water rate was measured by water meter. Photosynthetic criteria including photosynthesis rate, evapotranspiration, stomatal conductance, and resistance and concentration of photosynthetic pigments were measured in the 50% flowering stage.

Results indicated that the lowest and highest reduction in the concentration of chlorophyll a was found in MCC65 (6%) and MCC83 (3.3 times increase), respectively. Increasing salinity level increased the concentration of chlorophyll b in MCC65 and MCC139, the ratio of chlorophyll a/b in MCC92, MCC139, and MCC776, carotenoids concentration in MCC77, MCC92, MCC313, and MCC679 and total pigments in MCCMCC77, MCC92, MCC298, and MCC679. Increasing salinity levels led to higher evapotranspiration in 14 genotypes except for MCC65, MCC95, and MCC298 in which 37, 54, and 63% decrease of this parameter was observed. Increasing salinity level increased photosynthesis rate in 7 genotypes of MCC12, MCC65, MCC72, MCC92, MCC95, MCC679 and MCC776 among which MCC95 and MCC679 showed the highest percentage increase (61 and 53%, respectively). The highest increase in sub-stomatal CO2 (51, 49, and 40 ppm) with increasing salinity levels, was found in MCC485, MCC776, and MCC313, respectively. An increase of 28 and 8% in stomatal conductance was found in MCC65 and MCC95. Stomatal resistance was only reduced in MCC77, MCC420, and MCC29. Higher salinity levels also led to 3.4 times, 67, 14, and 13% increase in instantaneous water use efficiency in MCC95, MCC65, MCC92, and MCC298, respectively. Biomass and seed yield declined in all genotypes by salinity. The highest seed yield was observed in MCC65, MCC77, MCC92, and MCC95 with 142, 148, 167, and 166 g.m-2 respectively in saline conditions. There was a negative significant correlation between seed yield and evapotranspiration (r=-0.43**), and stomatal resistance (r=-0.38**), and a significant positive correlation between seed yield and biomass (r=0.61**) and photosynthesis (r=0.24**) and stomatal conductance (0.36**).

In general, the results of this experiment indicated the diversity among chickpea genotypes for salinity tolerance caused by saline irrigation water. Studying some photosynthetic criteria in 17 kabuli-type chickpea genotypes under salinity stress showed high diversity in physiological responses of chickpeas to salinity stress which could be used in the selection and breeding of salt-tolerant cultivars. MCC65, MCC77, MCC92, and MCC95 were superior in most studied criteria in saline conditions and even performed, unlike the declining trend of the other genotypes. It seems that these genotypes could produce reasonable seed yield in salinity levels up to 8dS.m-1.