جستجوی مقالات مرتبط با کلیدواژه « محلول پاشی » در نشریات گروه « زراعت »

Onion (Allium cepa L.) is a species of the Alliacea family. It is of great economic importance in Hormozgan province, Iran, which is ranked the second among the largest producers of onion in Iran in terms of cultivated area (8147 ha) (Agricultural statistics, 2021). Conventional Irrigation have undoubtedly helped in improving both bulb yield and quality of onion, but lately, it was arising many novel trends in Irrigation. Using of chitosan as an antiperspirant compound is one of these trends, as it can improve the water use efficiency (Geries et al., 2020). Chitosan is a member of the polysaccharides which is considered a useful natural polymer and is produced by alkaline N-deacetylation of chitin. Ahmed et al. (2019) reported that positive effect of chitosan nanoparticles on onion, as it significantly promoted seed germination and radical length under salt stress. The best treatment on germination was 0.3% of nano chitosan. Growth variables (plant height, leaf area, fresh and dry weights of the shoot and root) were increased significantly. Nevertheless, data on the utilization of chitosan for onion are meager in Iran. In this way, this study was carried to consider the impact of irrigation periods and chitosan as a biological elicitor on onion cultivar of Taki yellow, uniquely the adjustment in yield and quality properties.

This study was carried out at the private farm in Sohrabi village, Shamil district, Hormozgan province, Iran, conducted during 2020-2021 growing season. The experiment was carried out as autumn planting. This experiment was conducted as split-plot arrangement based on a complete randomized block design with 3 replications. Treatments were three irrigation periods and three doses of chitosan as main and sub plot, respectively. In this experiment 3 irrigation periods (such as two days, four days and six days) and 3 doses of chitosan (including zero, 1000 and 2000 ppm) with constant density of 63 plants m-2 yield and yield components (such as mean onion weight, length and diameter, onion shape index and dry matter content) and harvest index of onion were measured.

This study was conducted to assess the potential effects of irrigation periods and foliar spraying with chitosan, on the growth, yield quality of onion bulbs. In this experiment, nearly all measured traits were significantly (P<0.01) affected by irrigation periods and doses of chitosan. Results showed two forms of chitosan treatments (chitosan 1000 and 2000 ppm) were the most effective treatments for vegetative growth characters (plant height and Dry weight of shoot per plant), yield and its components (bulb dry matter %, bulb length, bulb diameter and total bulb yield) while chitosan at 0 ppm gives the highest values for harvest index in each irrigation periods. Also, results showed more irrigation (Two days) was the most effective treatments for vegetative growth characters, yield and its components. Therefore, according to these results, under deficit irrigation conditions, chitosan can reduce the effects of drought stress on onion more than No foliar application. In this regard, Shamekh, Jafari & Abdollahi (2021) the effect of proline, chitosan and its derivatives on photosynthetic pigments, chlorophyll fluorescence indices, qualitative characteristics and yield of greenhouse tomato (Lycopersicon esculentum Mill.) under deficit irrigation conditions and these researchers reported in their studies that under deficit irrigation conditions, chitosan and its derivatives can reduce the effects of drought stress on tomatoes more efficiently than proline.

The obtained results indicated that foliar application with chitosan had an important role in promoting and improving plant vegetative growth, and this led to improve in yield and yield components of onion in higher irrigation periods (four days and six days). The examination inferred that using chitosan to deliver highest yield in good quality with great the economic benefit was gotten from foliar application at 2000 ppm.

This study was conducted to investigate the effect of foliar application of amino acids on yield and yield components of oil rapeseed under late-season drought stress conditions. The experiment was conducted as factorial based on a randomized complete blocks design in the research farm of the Faculty of Agriculture at Tarbiat Modares University during the 2021-22 growing season. The experimental treatments were irrigation regimes at three levels (normal irrigation, withholding irrigation from 50% flowering stage, and withholding irrigation from pod forming) and foliar spraying at five levels (no foliar, foliar spraying 0, 1, 2, and 3 g amino acids per liter of distilled water). The results showed that plant height, shoot dry weight, 1000-seed weight, harvest index, and biological and grain yield, number of seeds per pod, and the number of pods per plant were significantly affected by the interaction of irrigation regimes and foliar spraying. The highest plant height (166.5 cm), 1000-seed weight (3.58 g), number of pods per plant (131.4) and grain yield (4514 kg ha-1) were obtained by foliar spraying of two g amino acids per litre under normal irrigation conditions. According to the results, foliar spraying 2 g amino acids per liter had the most positive effect on the yield and yield components of oil rapeseed in all irrigation regimes (normal irrigation, withholding irrigation from 50% flowering stage, and withholding irrigation from pod forming). Therefore, upon approving in future research it could be recommended to use foliar spraying with 2 g amino acids per liter in oil rapeseed cultivation.

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.

Micronutrient elements play a key role in the formation of chlorophyll and function of photosynthesis, respiration, enzyme system and physiological processes of the plant and their deficiency has destructive effects on the growth, production and yield of the plant. This research was conducted in a factorial experiment based on a randomized complete block design with three replications on mung bean plant in the Research Farm of Bu-Ali Sina University, Hamedan, Iran, in 2019-2020 growing season. Two cultivars of Gohar and Partu and foliar spraying of zinc chelate, iron chelate, zinc nano-fertilizer, iron nano-fertilizer, and control (spraying solution with water) were tested. The maximum leaf area index (3.12), maximum growth rate (16.2 g m-2 day-1), and leaf area duration (157 day) were achieved by Gohar cultivar in the presence of foliar application of zinc nano fertilizer. Zinc nano-fertilizer had the greatest effect on the pods/plant (21.7), grains/pod (8.08), and grains/plant (164) of Gohar cultivar, which increased by 62, 22 and 62, 77.6 percent respectively, compared to the control. The highest biological yield (8599 kg ha-1) was obtained with Gohar cultivar when receiving foliar application of iron nanofertilizer and zinc nanofertilizer. The highest grain yield (2657kg ha-1) was obtained with Gohar cultivar subjected to nano-zinc foliar spraying, which was not significantly different from Parto cultivar in foliar spraying with zinc nano-fertilizer and caused 38% and 35% increases in grain yield of the two cultivars compared to the control, respectively. The highest harvest index was also obtained with Gohar cultivar supplemented by foliar spraying of zinc nano fertilizer, which increased the harvest index by 24% compared to the control. Foliar spraying of iron and zinc fertilizers caused significant increases in growth, biological yield and grain yield, as well as the content of these elements in the grain of both cultivars. The effect of zinc and iron nanofertilizers on the studied traits was more pronounced in Gohar variety than in Parto variety.

In order to investigate the effect of foliar application of micronutrient fertilizers at different phenological stages on the yield and quality of white bean seed (Almas cultivar)an experiment was carried out in twoconsecutive years (2016-2017). The experiment was done as arandomized complete block design with 16 treatments andthree replications in the Agriculture Research, Education and Natural Resources Campus of Boroujerd. Treatments included control(c), pre-flowering(G1), flowering(G2), pod stage(G3) , seed hardening stage(G4),) G1+ G2),) G1+ G3), (G1+ G4),( G2+ G3),( G2+ G4),( G3+ G4),( G1+ G2+ G3),( G1+ G2+ G4),( G2+ G3+ G4),( G1+ G3+ G4),( G1+ G2+ G3+ G4). The results showed that the highest grain yield (5354kg.ha-1) belonged tothe foliar application in three stages of before flowering, flowering and seed filing in the second year .Thelowest grain yield (3902kg.ha-1)obtaibed from the control treatment in the first year. the highest amount of iron and zinc belonged to the foliar application in three stagesof before flowering, flowering, and seed filling. The highest seed amount of iron and zinc was 112 and 39 mg.kg-1, respectively. Therefore, in order to achieve optimum grain yield, foliar application should be carried out in three stages of pre-flowering, flowering and seed filling stages.

In this research, the effects of foliar application of humic acid were evaluated on morphological traits of chicory (Cichoirium intybus L.) and pergularia (Pergularia tomentosa L.) in aeroponic system. Aeroponic system is a suitable method for investigating the effects of nutrient elements and optimizing growth of different plants in controlled conditions. The treatments were including control and 200, 400 and 600 mg/L humic acid. Foliar application of fertilizers was done at 20, 40 and 60 days after seed culture in aeroponic system. After 4 months, the morphological traits were measured. The results of ANOVA indicated that the effects of treatment were significant for plant height, root length, number and area of leaves, fresh and dry weights of the shoot and root in chicory and pergularia. The results in pergularia showed that 600 mg/L resulted in the highest plant height, root length, volume root, leaf number, dry and fresh weights of root and dry and fresh weights of shoot and the lowest of the mentioned traits were observed in the control. In the chicory, the results showed that the highest and lowest values of plant height, root length, volume root, leaf number, dry and fresh weights of root and dry and fresh weights of shoot belonged to the highest concentration of humic acid and the control treatment, respectively. It can be said that the use of a 600 mg/L of humic acid in the aeroponic system can improve the quantitative characteristics of the pergularia and chicory.

Improving the nutritional status of plants is an effective method for enhancing their ability to withstand drought stress. To evaluate the quantitative, qualitative, and antioxidant properties of castor plant under water deficit conditions stress and foliar application of chemical fertilizers, an experiment was conducted as a split-plot design in a completely randomized block design with three replications. The first factor was irrigation levels including control (normal irrigation), irrigation after 80 mm and 140 mm evaporation from the pan evaporation in the main plots, and eight spraying chemical fertilizers (sulfur, potassium, nitrogen, sulfur+potassium, sulfur+nitrogen, potassium+nitrogen, sulfur+potassium+ nitrogen and control (no spraying)) were included in subplots. The highest proline content, catalase, peroxidase, superoxide dismutase, and total phenol were obtained under irrigation after 140 mm of evaporation conditions and foliar application of nitrogen+potassium+sulfur. Also, the highest grain yield, oil yield, and the lowest oil percentage were observed in the nitrogen+potassium foliar treatment under irrigation conditions after 20 mm of evaporation. Although the content of malondialdehyde increased in water deficit stress treatments, nitrogen+potassium+sulfur and nitrogen+potassium foliar application significantly reduced the peroxidation of membrane lipids (malondialdehyde) under irrigation conditions after 80 and 140 mm of evaporation compared to the control treatment. In conclusion, foliar application of chemical fertilizers in castor can improve the resistance to water stress by strengthening the antioxidant system and then increase its grain and oil yield.

water deficit stress during growth and flowering is one of the most major environmental constraints, which influences seed grain filling and consequential germination and early growth stages of plants. In this study, the impact of foliar application of micronutrients (control, Fe, Zn, Fe + Zn, nano- Fe, nano- Zn, nano- Fe + nano- Zn) on quinoa at 2 reproductive stages (50% and 100% of flowering stage) were evaluated under 2 levels of water deficit stress, control (-0.03±0.045) bar and water deficit stress (-9±0.045) bar. The results showed that germination traits including percentage, rate, mean germination time, germination uniformity, seedling length and weight index as well as chlorophyll and carotenoid content were significantly affected by micronutrient foliar application, foliar application time and water deficit stress. water deficit stress decreased the percentage and rate of germination and seedling indices, but foliar application of micronutrients reduced the adverse effects of foliar application of micronutrients. Foliar application of micronutrients also increase the amount of photosynthetic pigments. The findings of this research show that foliar spraying with nutrients, especially nano-iron + nano-zinc, increases the germination indices to improve the germination and growth of quinoa seedlings under water stress conditions.

Drought stress is one of the most important factors affecting crop yield especially in irrigated agriculture in arid and semiarid regions. Application of some stress modulators (vermicompost, mycorrhiza, putrescine and zinc nanooxide) increases growth, yield and the resistance of plants against various environmental stresses such as drought. However, the effect of these compounds alone has been investigated on modulating the effects of stress, there are fewer reports about their interaction effects. In this experiment, the interaction effects of organic, biological and mineral fertilizers and stress modulators were investigated on the improvement of current photosynthesis, dry matter remobilization process, grain filling components and grain yield of barley under water deficit conditions.

To investigate the interaction effects of some stress modulators (vermicompost, mycorrhiza, zinc nanooxide and putrescine) on the contribution of dry matter remobilization and grain filling components of barley under water deficit stress conditions, a factorial experiment in randomized complete block design with three replications was conducted in research greenhouse of Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran, in 2022. The experimental factors were included irrigation in three levels (full irrigation as control, irrigation withholding at 50% of the heading and 50% of the booting stages, equal to codes 55 and 43 of BBCH scale, as moderate and severe water limitation, respectively), application of biofertilizer, and organic and inorganic fertilizers in four levels (no application of fertilizers as control, application of vermicompost, application of mycorrhiza, combined application of vermicompost and mycorrhiza), and foliar application of putrescine and zinc nanooxide in four levels (foliar application of water as control, foliar application of 0.4 g.L-1 Zn nanooxide, foliar application of 0.8 mM putrescine, combined foliar application of Zn nanooxide and putrescine). Mycorrhiza fungus (mosseae species) was purchased from Zist Fanavar Turan company and according to copany’s protocol, 10 g per kg soil was used. Vermicompost was purchased from Gilda company and according to copany’s protocol, 50 g per kg soil was used. Zinc nanooxide production of China, with an average particle size of less than 30 nm, a specific surface of more than 30 m2.g-1, a Zn content of about 65.21% and a purity of 99%, was purchased from Jahan Kimia company, Urmia, Iran. The barley variety used in the experiment was Nobahar variety, which was cultivated with a plant density of 400 seeds per m2.

The results showed that the combined application of stress modulators (vermicompost, mycorrhizal, Zn nanooxide and putrescine) under irrigation withholding at booting stage conditions decreased dry matter remobilization from shoot and stem (22.32% and 25.65%, respectively) and their contribution in grain yield (52.92% and 56.95%, respectively) compared to the no application of biofertilizers and no foliar application of putrescine and Zn. In contrast, application of stress modulators under irrigation withholding in booting stage conditions increased total chlorophyll (24.91%), current photosynthesis (62.57%), contribution of current photosynthesis in grain yield (30.54%), grain filling rate (6.62%), grain filling period (18.06%), effective grain filling period (27.67%) and grain yield (25.18%) compared to the no application of biofertilizers and no foliar application of putrescine and Zn.

The findings of the current experiment showed that the application of stress modulators (vermicompost, mycorrhizal, Zn nanooxide and putrescine) can increase grain yield of barley under water limitation conditions by improving the current photosynthesis and grain filling components.

Safflower has been cultivated in different parts of Sistan and Baluchestan since ancient times and is relatively tolerant of drought. It has many medicinal and food uses for the people of this region. Saravan is also one of the arid regions of the country, so the cultivation of plants compatible with these regions can be effective to improve agriculture in this region. Several studies have been shown that a small amount of nutrients, particularly Zn and Mn applied by foliar spraying can significantly increase the yield of crops Also, foliar nutrition is an option when nutrient deficiencies cannot be corrected by applications of nutrients to the soil. It is likely therefore, in open-field conditions, where the factors that influence the uptake of the nutrients are very variable, foliar fertilization is a privilege. Among the micronutrients, Zn and Mn nutrition can affect the susceptibility of plants to drought stress. Zinc plays an important role in the production of biomass. Furthermore, zinc may be required for chlorophyll production, pollen function, fertilization and germination. Mn plays essential roles in the metabolism of isoprenoids, chlorophylls, carotenoids and phenolics. External application of Mn2+ increases photosynthesis, net assimilation, and relative growth and yield.

this experiment was conducted to investigate different levels of irrigation and foliar application of zinc and manganese sulfate in November 2020 in the research farm of Saravan Higher Educational Complex as a split plot in a randomized complete block design with three replications. Experimental treatments include three levels of irrigation, including: full irrigation, cessation of irrigation at the beginning of stem emergence and cessation of irrigation at the stage of flowering, and three levels of foliar application with zinc sulfate (three per thousand), manganese sulfate (three per thousand) and no foliar application. Study traits include speed, plant height, number of branches, number of heads per plant, seed weight per plant, head weight per plant, 100-seed weight, biological yield, grain yield and harvest index (division of grain yield by biological yield by percent). Data analyzed was performed using SAS software (version 9/1) and mean comparisons at the level of 5% probability were performed using LSD test.

The results showed that the interaction effects of irrigation and foliar application in plant height, number of branches, number of heads, 1000-seed weight, seed-per-plant weight, head-per-plant weight, biological yield, grain yield, harvest index and chlorophyll meter (SPAD) were significant (P≤ 1%). foliar application with zinc sulfate increased grain yield more than three times in all irrigation treatments, also grain yield in foliar application with zinc sulfate in non-interruption irrigation treatment (693 kg) Per hectare was seven times higher than the conditions for stopping irrigation at the stage of stemming and lack of foliar application (100 kg ha-1). In all irrigation treatments, foliar application of zinc sulfate Element was relatively superior to manganese sulfate and no foliar application. The highest grain yield was observed in the treatments of non-interruption of irrigation, cessation of irrigation in flowering stage and cessation of irrigation in stem stage, respectively. Was seven times the grain yield. In general, foliar application of zinc sulfate can be used as an agricultural solution to increase yield and reduce the effects of cessation of irrigation at the end of the growing season in safflower in Saravan climate. In general, the results of this study showed that under different conditions of irrigation interruption, foliar application of zinc sulfate and manganese can play an important role in mitigating the effects of drought stress on safflower compared to no foliar application. Discontinuation of irrigation at the end of the growing season in the stem and flowering stages reduced the seed yield of safflower compared to full irrigation conditions. Zinc sulfate foliar application improved yield-related traits in this plant, zinc sulfate foliar application increased grain yield about twice and in manganese sulfate foliar application this increase was about 30% compared to non-foliar conditions. The highest correlation was observed with number of heads per plant, head weight, seed weight per plant and number of branches. Due to the alkalinity of the soil in dry areas and the non-absorption of these elements by the plant and the positive effects of this element in relation to the defense system and photosynthesis of the plant, foliar application of zinc sulfate Element is recommended for safflower in Saravan climate.

Drought stress is one of the most important environmental factors involved in the growth and yield of wheat reduction and causes many damages by disrupting morphological and physiological processes. On the other hand, putrescine as a growth stimulant with antioxidant properties in the plants can inhibit the destructive effects of dehydration stress. For this purpose, a factorial experiment based on a completely randomized design with three replications was carried out in the greenhouse of the Faculty of Agriculture, University of Mohaghegh Ardabili. Factors included water deficit stress (control, 85% and 65% of field capacity), wheat cultivars (Kuhdasht, Zagros, Gonbad and lines 23, 24, 25, 27, 28, 39 and 40) and putrescine (non-application, 0.088 and 0.176 g / L-1). Putrescine foliar application was performed in the three-leaf stage of the plant and dehydration stress was applied one day later for one week. Mean comparisons showed that dehydration stress decreased leaf chlorophyll index, F0, Fm, Fv / Fm, stem length and grain yield (grain number and grain weight) in some studied genotypes. The combination of 0.088 g / L-1 putrescine and drought stress improved the chlorophyll index (28.16%) and the amount of photosystem two (10.54%) compared to the control conditions. Also, the dendrogram obtained from cluster analysis placed the studied genotypes under dehydration stress and putrescine foliar application in three groups. In general, foliar feeding of 0.088 g / L-1 putrescine is more effective and recommended for the photosynthetic system improvement and tolerance of wheat plant to dehydration stress. Among the studied genotypes, Koohdasht, Zagros and Line 27 were more tolerant to dehydration stress due to putrescine-enhanced photosynthetic system and improved grain yield.

drought stress is the most important abiotic stress that limits the growth and development of agricultural plants. Zinc is one of the required elements for plant chemical processes, and its application in water shortage conditions can improve the effects of drought stress. Studies have shown that the application of zinc fertilizer to reduce the negative effects of drought stress leads to an increase in yield and yield components of agricultural plants. Therefore, this study was conducted in order to evaluate the application of different forms and concentrations of zinc fertilizer on the yield and oil quality of Neptune variety rapeseed oil under water stress conditions during the years 2019 and 2020 in Biston region located in Kermanshah province.

The experiment was carried out in the form of a split-plot design based on a randomized complete block design in four replications. Water stress treatment as the main factor (no stress, interruption of irrigation at the beginning of flowering and interruption of irrigation at the beginning of the formation of khorjin), foliar treatment as a secondary factor at two levels (spraying zinc sulfate solution and foliar spraying zinc nanochelate) with three concentrations of zero, 3 and 5 per thousand. After collecting the test data, they were analyzed using SAS software.

The results showed that the effect of drought stress and application of zinc sulfate on the characteristics of seed yield, biological yield, seed oil percentage, seed oil yield, erucic acid percentage and oleic acid percentage were significant. Also, according to the results of the comparison of the average test data, it was found that increasing the concentration of zinc sulfate and nano zinc application increased the grain yield and biomass up to 2839 kg/ha and 14634 kg/ha, respectively. The effect of zinc nanochelate on the increase of these two traits was greater than that of zinc sulfate. Oil percentage and yield decreased in both levels of water stress. According to the results, it was found that increasing the concentration of zinc and especially the nano form increased the percentage up to 43.6% and the yield of seed oil up to 1423 kg per hectare. In addition, it was found that water stress reduced the percentage of oleic acid in rapeseed oil, but nanozinc foliar application partially compensated for this decrease and increased the percentage of oleic acid to 65.75%.

According to these results, it was found that although the percentage of oleic acid decreased with the interruption of irrigation during the flowering and podding stages, the results showed that the application of zinc nanochelate in the conditions of drought stress and the absence of drought stress had a more positive effect on increasing the percentage of oil oleic acid. Therefore, the application of nano zinc chelate can be suggested in the conditions of drought stress to increase the yield and quality of rapeseed oil in the region. As a result, in order to achieve the maximum seed yield and high oil quality in rapeseed, a concentration of 5 per thousand zinc nanochelates can be used in the absence of drought stress.

Salinity is one of the most destructive environmental stresses, which affect almost every aspect of physiology and biochemistry of a plant. It is a serious threat for crop yield especially in arid and semi-arid regions. Several strategies have been suggested in order to decrease the toxic effects caused by salinity on plant growth, among them use of silicon and bio fertilizers play important role in yield improvement. In this regard, an experiment was carried out as factorial based on randomized complete block design with three replications in research greenhouse University of Mohaghegh Ardabili  in 2021. The investigated factors were included salinity levels [no application of salinity as control, application of 30 and 60 mM salinity (1.8, 2.76 and 5.53 dS.m-1 respectively)], bio and organic fertilizers (no application as control, vermicompost, mycorrhiza, both application of vermicompost and mycorrhiza) and nanosilicon foliar application (foliar application with water as control, foliar application of 30 and 60 mg.L-1 of nanosilicon). The results showed that both application of vermicompost and mycorrhiza, foliar application of 60 mg.L-1 of nano silicon under no salinity decreased dry matter remobilization from the stem (209.01%) and aerial parts to grain (80.49%), but increased stomata conductance (50.47%), flag leaf protein (26.17%), current photosynthesis (153.41%), the contribution of current photosynthesis in grain yield (89.56%) and  grain yield (88.88%) compared to no appllication bio and organic fertilizers and nanosilicon under 60 mM salinity conditions. Based on the results this study, it can be suggested  that the application of bio and organic fertilizers and nanosilicon can increase the grain yield of triticale under salinity conditions due to improving stomata conductance and current photosynthesis.

In order to study the effect of hormone cytokinin on morphological and yield traits of sunflower cultivars under terminal heat stress, a field experiment carried out in a split plot factoril in randomized complete block design with three replications at the research farm of Shahid Chamran University of Ahvaz in 2021. The main plots consisted of three sowing dates; 3 Feb, 18 Feb and 5 Mar, the sub-plot consisted of factorial arrangement of different concentrations of cytokinin (0, 25 and 50 and 75 μm l-1, Kinetin), and sunflower cultivars (Qasem and Oskar). Sowing date with desired temperature considered as control and delayed and late sowing dates considered as mild and severe heat stress so that the flowering and grain filling periods faced with terminal heat stress. Results showed that terminal heat stress in delayed and late sowing dates caused a decrease in plant height, grain number per head, head diameter, 1000-grain weight, biological yield, oil percentage, and oil and grain yield. The optimum hormone concentration needed to exhibit a considerable increase in studied traits of sunflower cultivars under heat stress was 50 μm l-1,particularly, in Late sowing date sunflower plants, foliar application of cytokinin (50 μm l-1) increased grain yield (by 17% and 15%), biological yield (by 5% and 8%), and oil yield (28 and 13%), in Oscar and Qasim cultivars, respectively. Results show that foliar application of cytokinin (50 μm l-1) can be considered as a strategy to enhance the grain yield of sunflower cultivars under under heat stress conditions in tropical regions such as Khuzestan.

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

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

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

In saline condition, addition to salinity stress, nitrogen deficiency is also observed. In order to investigate the response of yield, yield components, and nitrogen efficiency of cotton to supplemental nitrogen application in saline conditions in optimum and delayed cultivation, a factorial experiment in a randomized complete block design with three replications was done in Sabzevar Islamic Azad University in 2017-2018. Factors were: planting date (optimum and late) and nitrogen levels (0, 2.5, 5, and 7.5 kg.ha-1) as a foliar application on the bolling stage as Urea form. Delayed planting reduced the number of bolls per plant (6.59 %), boll weight (17.33%), seed cotton yield (14.70 %), nitrogen uptake efficiency (23.2 %), and nitrogen use efficiency (11.32 %) compared to optimum cultivation. Foliar application of 7.5 kg N.ha-1increased the number of bolls per plant (67.6%), boll weight (47.2%), seed cotton yield (73.2%), nitrogen uptake efficiency (45.1%), and nitrogen use efficiency (41.2%) compared to control. Sprayed due to lack of solution. The highest plant height, number of reproductive branches, lint percentage, lint yield, and agronomic nitrogen use efficiency in optimum planting date and foliar application of 7.5 kgN.ha-1were obtained which was not significantly different from foliar spraying of 5 kgN.ha-1. Nitrogen foliar application could not improve the negative effects of planting delay on yield and yield components of cotton. In general, the results of this experiment showed that the best seed cotton yield can be achieved by planting at the optimum date and spraying 5 kg of nitrogen as a supplement at the beginning of the bolling stage that increases the efficiency of cotton nitrogen consumption in saline conditions.

The shelf life of orange ‘Thomson Navel’ (Citrus sinensis var. Thomson Navel) is low. One of the important factors in maximum increase of fruit quality and its nutritional value is the presence of calcium and potassium in fruit tissue. Absorption of essential elements from the soil by the roots and their transfer to the aerial part of the plant, including entry into the fruit tissue are important challenges. Calcium deficiency in citrus fruits is possible due to reduced absorption from soils. The application of these elements in the form of foliar application solves this challenge. The aim of this study was to determine the appropriate frequency of combined treatment of calcium and potassium (one to four times), before and after harvest, on shelf life and fruit quality of Thomson Novell cultivar, including calcium, vitamin C and soluble solids (°Brix).

Treatments were without foliar application of calcium, once foliar application of calcium (in June), twice foliar application of calcium (in June and July), three times foliar application of calcium (in June, July and September), four times foliar application of calcium (in June, July, September and October), without foliar application of potassium, once foliar application of potassium (in June) and twice foliar application of potassium (in June and July), alone or in combination with a week distance and before harvesting fruits. After harvesting, all fruits were treated with 3 per 1000 calcium for 5 minutes as plunging. Fruits without foliar application of calcium and potassium were considered as controls. Calcium foliar application was performed at a constant rate of 3 per1000 and potassium foliar application at a rate of 2 per 1000. The last stage of treatment of fruits with calcium was done after harvest and by immersion in a solution of 3 per 1000. The experiment was conducted in a completely randomized block design with three replications in Kharik village of Sari city. The fruits were stored at the temperature of 5°C and 85% relative humidity for 3 months. Traits of length, diameter, skin diameter, weight, juice volume, decay, vitamin C, calcium, total solid soluble (TSS), titration acidity (TA) and acidity (pH) of fruits were measured after 3 months’ storage.

The results showed that the most vitamin C (97.69 mg/100 ml fruit juice), fruit weight (242.20 g) and fruit juice volume (115.70 ml) were obtained in fruits treated with twice foliar application of calcium (in June and July at a rate of 3 per1000) together with twice foliar application of potassium (in June and July at a rate of 2 per1000). The highest diameter (78.92 mm) and the lowest decomposition were obtained in fruits treated with twice calcium (June and July at a rate of 3 per1000) together with once potassium (June at a rate of 2 per1000). The highest amount of fruit calcium (165.30 g/kg DW) was calculated in the treatment of 3 times foliar application of calcium (in June, July and September at a rate of 3 per1000) together with once foliar application of potassium (in June at a rate of 2 per1000).

In general, based on the findings of this study, foliar application of Thomson Novell cultivar through twice calcium (in June and July, at a rate of 3 per 1000) and once with potassium (in June at a rate of 2 per1000) and twice with potassium (in June and July, at a rate of 2 per1000) before harvest along with plunging into 3 per 1000 of calcium after harvest (for all oranges) is suitable for maintaining the quantity and quality of fruits during storage and this treatment is recommended.

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

Saline conditions and especially saline water can interfere with the uptake of ions by plants and lead to a decrease in crop yields. On the other hand, the application of potassium sulfate under these conditions reduces the negative effects of salt stress and leads to an increase in crop yield. Therefore, this study was conducted to investigate the effects of saline water irrigation on ionic ratios and yield of cotton in a two-year trial at Rudasht Salinity Research Station, Isfahan.

This experiment was conducted as a factorial split-plot design with four replications in a randomized block design. In this experiment, main plots include irrigation treatments of 4 (control), 8 and 12 ds.m-1 and sub-plots include factorial combination of three genotypes (mutant genotype LM 1673, LM 1303 and Shayan) with foliar sprays of potassium sulfate at three rates of 2, 4 and 6 kg per 1000 liters of water per hectare with control treatment.

The results showed that the effect of salinity treatments and cultivar and the interaction effect of year*salinity*number of spray solutions were significant on the amount of calcium in stems and leaves, chlorine in stems and leaves, potassium in stems and leaves, sodium in stems and leaves, and yield. The effect of potassium sulfate foliar spraying on calcium in stem, chlorine in leaf, potassium in stem and leaf, sodium in stem and leaf, and yield was also significant. In the two experimental years, increasing the salinity of the irrigation water resulted in an increase in the content of elements such as calcium, sodium and chlorine in the stems and leaves, but a decrease in the content of potassium. The results showed that in the first year of the experiment, the highest calcium content in the stem occurred with 4.1 mg.g-1 when treated with an irrigation salinity of 12 ds.m-1 in the genotype LM 1303 and a foliar spray of 6 kg.ha-1 potassium sulfate. In the second year, the amount of calcium in stem and leaf tissue of cotton was obtained in irrigation treatment with water with salinity 12 ds.m-1 and variety LM 1303 in foliar treatment with 4 kg.ha-1 potassium sulfate (3.16 mg.g-1) and foliar application of 6 kg.ha-1 potassium sulfate (4.33 mg.kg-1), respectively. In the first year of the experiment, the highest chlorine content in the stem was 23.4 mg.g-1 under irrigation conditions with saline water of 12 ds.m-1 and in the cultivar LM 1303 with foliar spray of 4 kg.ha-1 potassium sulfate. In the second year, the chlorine content of the cotton stem and leaves was measured when irrigated with water with a salinity of 12 ds.m-1 and the variety LM 1303 when foliar treated with 4 kg/ha of potassium sulfate (3.23 mg.g-1) and the solution spraying of 6 kg.ha-1 of potassium sulfate (5.92 mg.kg-1), respectively. In both years, potassium content in stems and leaves decreased with the increase in salinity of irrigation water, while foliar application of potassium sulfate led to its decrease. In the first and second year, the highest cotton yield of 3918 and 3696 kg ha-1, respectively, was obtained with genotype LM 1303 at salinity of 4 ds.m-1. Foliar application of potassium sulfate also increased the yield of sorghum, so that the highest yield of 3016 kg.ha-1 was obtained with application of 6 kg.ha-1 potassium sulfate.

The results show that the yield of genotype LM 1303 increased under saline and non-saline conditions by foliar application of potassium sulfate. Therefore, it can be said that the variety LM 1303 and foliar application of potassium sulfate can be used to improve ionic ratios in cotton and obtain the highest cotton yield under saline conditions in the region.

This study attempts to investigate the effect of application of humic acid and seaweed extract on morphology, growth, yield, and yield components of quinoa under drought stress in 2018-2019 in two different locations, Qasr Shirin and Dalahou. It has been performed as split plots in a randomized complete block design with 4 replications. Experimental treatments include three irrigation treatments (full irrigation, irrigation cut-off at the beginning of flowering and irrigation cut-off at the beginning of seed filling) and foliar spraying treatments with different amounts of humic acid (foliar application at the rate of 1.5 kg / ha and 2 Kg / ha) and seaweed extract (foliar application at 1 kg / ha and 1.5 kg / ha) along with a control treatment. Results show that seed yield in Dalahou region under normal condation has been 24.78% higher than Qasrshirin region. Seed yield in different irrigation treatments under the influence of foliar application show that in all irrigation treatments, the effect of foliar application of humic acid and seaweed extract on seed yield has been positive compared to the control. In full irrigation conditions, the highest seed yield is obtained from foliar application of humic acid, while in irrigation cut-off treatments, the effect of seaweed extract on seed yield has been better than humic acid. The weight of 1000 seeds in quinoa produced in Dalahu region has been more than Qasrshirin region but in both regions drought stress has reduced the 1000 seeds weight. In all irrigation treatments, application of humic acid and algae extract has increased 1000-seed weight.