نشریه تحقیقات علوم زراعی در مناطق خشک
سال پنجم شماره 1 (پیاپی 9، بهار و تابستان 1402)

Wheat (Triticum aestivum L.) is the main staple food in many parts of the world including Iran. This crop is one of the most cold stress tolerant crops amongst domesticated plants. Still, Severe freezing in winter and early spring may influence the growth and survival of wheat plants and decrease its growth and seed yield. The absolute minimum temperature in North Khorasan reach to -20°C in many years and if a cold tolerant cultivar is not choose or if wheat field in not hardened properly then the freezing stress might be injurious. Therefore each new cultivar that introduced to the region should firstly test to chilling and freezing stress. This experiment was carried out to explore freezing tolerance of two wheat cultivars (Mihan and Pishtaz) under controlled and field conditions with spraying paclobutrazol (PBZ) and non-spray.

 Seeds of two wheat cultivar Mihan and Pishtaz were sown in plastic pots in 20th of September in Bojnord and kept them in open space until third leaf stage in order to grow in the same climatic conditions as they will grow in the future. All plants could receive the enough temperature for winter hardening then they transfer to Mashhad to apply freezing stress in controllable freezer. After applying freezing stress all pots transferred into research greenhouse at Ferdowsi University of Mashhad with light density of 500±50 μmol m-2 s-1 and light/dark cycle of 14/10.   Sampling and measurement were arranged after four weeks that plants grown in the greenhouse.  Measured parameters included electrolyte leakage, plant height, green leaf area, plant survival rate and number of tiller and leaves per plant. Field experiment was arranged in the Kohnekand Agricultural research center in Bojnord. Both experiments conducted as a split-split plots based on a completely randomized design with three replications. The main plots in green house were six freezing temperatures (zero,-4, -8, -12, -16, and -20°C), the sub-plots were three paclobutrazol (PBZ) concentrations (foliar application of zero as control, 30 and 60 mg L-1) and the sub-sub-plots were wheat cultivars (‘Mihan’ and ‘Pishtaz’) with three replication. In the field experiment main plots were three sowing dates (16th Oct., 13th Nov. and 5th Dec.), and the sub-plots and sub-sub-plots were the same as controlled experiment. Data were statistically analyzed using the SAS software (SAS version 9.2). The LSD test (p=0.05) was used to determine which treatment is statistically different from the others.

The results showed that, Mihan cultivar produced more leaves but lower tiller per plant compare to pishtaz, Up to -16°C but at and -20°C the tiller number was also not significant. But reduced to -20°C, the electrolyte leakage of membrane increased significantly by 71.5%. The electrolyte leakage in Mihan cultivar was significantly lower than that of Pishtaz cultivar when freezing temperature was decreased lower than -16°C.  PBZ also caused shorter plants but less leaf lost observed due to freezing stress in both cultivars. Delay in sowing date from 16th Oct. to 13th Nov. and to 5th of Dec. caused 19% and 31% seed yield reduction in two wheat cultivars, respectively. While the average seed yield of Mihan was 17% higher than pishtaz cultivar. Biological yield also followed the same trend of grain yield. PBZ application did not show any significant effect on seed yield, this result might be due to ABA production after PBZ spraying, which can negatively affect yield component formation.  Based on our results temperatures below -12°C is much more injurious that higher temperatures, and the advantage of freezing tolerance wheat cultivars appears in lower temperatures.

Based on our results, Mihan cultivar has higher freezing tolerance capacity and in temperature below -12°C and PBZ application this cultivar can alleviate negative effects of freezing stress. Therefore, introduction and extension of this cultivar in mountain regions and those areas that the risk of freezing stress is high might reduce the risk of freezing damage in Bojnord area and at the same time produce reliable grain yield.

Grapes with the scientific name (vitis vinifera L) have a prominent position among the country's fruit trees as from the entire level of gardens in the country,  about 306 thousand hectares, equivalent to 11.4% , belongs to small fruits and about 96.2% of which is related to the grape surface. West Azerbaijan province is one of the most important regions of Iran for planting vines and the area under grape cultivation is close to 21808 hectares. Subsequently its production amount is reported more than 265 thousand tons which is important in the prosperity of the region's economy in terms of currency. According to the importance of grapes and raisins and its position in the country's economy and region and due to the lack of basic information about the weed status of this product at the national level and especially in the state of West Azerbaijan (which has an important share in the production of grapes), with identifying weed cover and determining the abundance status and distribution of weed species, it can be achieved to the substructure information for designing weed management programs in this important crop.

 Miandoab city (has a semi-arid climate with hot and dry summer and semi-humid winter) has 2694 square kilometers area with geographical longitude 46 degrees and 6 minutes east of the Greenwich meridian and 36 degrees and 58 minutes north From the equator. It is located in the middle of the plains leading to Lake Urmia with a height of 1314 meters above sea level. In order to identify and determine the density and dominance of weeds in the vineyards of Miandoab city 25 vineyards in 25 areas of the Miandoab city were investigated in late May 2016. Frequency, uniformity, density, mean density and dominance index of different weed species were calculated in each garden. Then experiment to investigate the effect of weeds on grape yield is done in mid-September. For this Weed biomass from 25 rural areas were collected in 4 replications. At the same time as sampling weeds, also characteristics of grape were evaluated in 4 replications. These characteristics include fruit weight, volume, length, density and number of berries per grape cluster. After calculating the Shannon-Wiener index of different regions, Ward's cluster analysis with SPSS software was used to compare and group regions. After these steps, the desired map was prepared using Google earth software.

In total, 61 species of weeds from 24 plant families were identified in the vineyards of Miandoab city. 21 species were present in more than three regions. In terms of density, Sogli Tappeh, Mullah Shahabuddin and Shabilo villages had the highest weed density with 49.6, 49.5 and 46 plants per square meter, respectively. From the 61 identified species, 32 species (46%) belonged to 4 families: Gramineae, Asteraceae, Fabaceae and Brassicaceae. These 4 families with 11, 10, 7 and 4 species had the highest diversity in the city, respectively. In terms of weed abundance index (AI) Glycyrrhiza glabra, Sorghum halepense and Convolvulus arvensis were recognized as the dominant weeds in the city, respectively. Gara Tappeh, Gog Tappeh and Mameh Del villages with 26, 24 and 22 species, respectively, with the highest variety And Islamabad, Hyderabad and Hosseinabad villages had the least variety with 10, 10 and 11 species, respectively. Results of comparing the means of different traits of grapes (volume, weight, length and density of fruit and number of berries per spike) indicate a significant difference in the level of 5% probability between villages. The results showed that there was a positive and significant correlation between weight, length, volume and fruit density at the level of 1% probability. Thus, it is clear that increasing any of the above parameters causes the weight of the berry to increase.

In general, according to the knowledge of density, dispersion and species of weed ‎‎in the studied vineyards and using the right management methods the amount of interference of problematic species can be reduced and also the entry of weeds, especially problematic species, from one area to another susceptible area can be prevented. In addition by studying the climatic conditions, climate and soil of the region and also, by having information about the common management methods in the region, it is possible to understand the reasons for the presence and changes in the density of some species in some areas and used this information in integrated weed management.

The quinoa plant (Chenopodium quinoa Wild) belongs to the Amarranthaceae family. This plant has a high nutritional value and shows tolerance to abiotic stresses such as drought and salinity. Drought stress is known as an important environmental stress that creates serious limitations for crop production all over the world. Drought stress may cause the production of reactive oxygen species in plants, which damages lipid and protein structures and causes the cell membrane to lose permeability and selectivity. Potassium is a mineral substance that is necessary for various biophysical and biochemical processes. It is important for the production of crops and can be a limiting factor for the production of crops under certain environmental conditions such as salinity and drought. Quinoa plant is somewhat resistant to drought and Kerman province is considered one of the dry areas. Therefore, cultivation of drought-resistant plants and strategies to increase drought resistance and improve agricultural and physiological traits in this plant are necessary. Considering that no research has been done in this field on quinoa plant in the climatic conditions of Kerman region, the present study was conducted to investigate the effect of potassium sulfate fertilizer on seed yield and some physiological traits of quinoa plant under different irrigation treatments.

The experiment of split plots based on randomized complete blocks design with three replications was conducted at the station of Research in the 2020-2021 crop year, Agriculture and Natural Resources Center in Kerman province of Iran. The main factor included three levels of irrigation treatment (irrigation to the full maturity stage (control), irrigation to the beginning of the flowering stage, and irrigation to the dough development stage) and the secondary factor included two levels of potassium sulfate fertilizer, including its application and non-application. Physiological traits including the content of chlorophyll a and b and carotenoids, ion leakage, malondialdehyde content and the activity of enzymes such as catalase, ascorbate peroxidase, peroxidase, polyphenol oxidase was measured. After confirming the normality of the data, the errors were also checked for normality. Then variance analysis of all traits and LSD mean comparison test at five percent level was performed with SAS software version 2.9.

The effect of irrigation factor and potassium sulfate on seed yield and all measured physiological traits (content of photosynthetic pigments, chlorophyll a, chlorophyll b and carotenoids), activity of antioxidant enzymes (catalase, peroxidase, ascorbate peroxidase and poly phenol oxidase), electrolyte leakage and malondialdehyde content) were significant. The highest seed yield (230.9 g/m2) was observed in control plants and the lowest (136.6 g/m2) in plants grown under irrigation conditions to the beginning of the flowering stage. Drought stress decreased the content of photosynthetic pigments and increased the activity of antioxidant enzymes, electrolyte leakage and malondialdehyde content. The application of potassium sulfate caused an increase in the seed yield compared to its non-application in all three irrigation treatments by an average amount of 25.8%. Physiological traits also improved with the application of potassium sulfate.

The yield of seeds and the amounts of photosynthetic pigments decreased in proportion to the increase in drought stress, and the ion leakage and malondialdehyde content increased, which indicated the harmful effects of this stress on growth parameters, photosynthetic apparatus, and cell membrane stability. The activity of antioxidant enzymes increased under stress conditions, which indicates the enzymatic defense responses to oxidative stress. The application of potassium sulfate led to the improvement of seed yield and physiological traits in both normal and drought stress environments alike. Due to the fact that drought stress affects the physiological traits and ultimately leads to a decrease in the seed yield of the quinoa plant, potassium sulfate fertilizer was used to compensate for its harmful effects.

Oat (Avena sativa L.) is a plant belonging to the Poaceae family and adapted to cold and moderate weather conditions. Avena genus includes annual herbaceous plants with economic and medicinal importance. Among the various aspects of agricultural management, choosing the right cultivar and planting date is the most noticeable, because even in similar climates and the same planting date, there is a great difference in the performance of different cultivars and genotypes. Due to the fact that high-yielding oat line and its appropriate planting date have not been introduced for Birjand region, this research was conducted with the aim of investigating the effect of planting date on some agronomic traits of four cultivated oat lines in Birjand.

In order to investigate the possibility of oat crop genotypes planting in Birjand, a factorial experiment based on a randomized complete block design with three replications was conducted in 2013 at the research farm of the Faculty of Agriculture, Birjand University. The two factors studied included four cultivated oat lines (A5, L2, L7 and bare oats) and three sowing dates (October 24, November 10 and November 26). In this study, traits such as plant height, inflorescence length, number of tillers per plant, number of days to emergence, stem elongation, ear emergence and to maturity, number of ear per square meter, number of seeds per ear, 1000 seed weight, grain yield, biomass yield, harvest index, seed protein percentage and protein yield were studied.

The effect of line on the studied traits except for the number of tillers per plant, number of ear per square meter and biological yield was significant. L7 line with 7003 and 1061 kg.ha-1 had the highest seed and protein yield, respectively. The effect of planting date on inflorescence length, number of seeds per panicle, seed yield, harvest index and protein yield were not significant. Delay in planting, although it caused a delay in emergence and especially a delay in the beginning of tillering, accelerated the reproductive growth of the plant. So that on the date of planting November 26 compared to October 24, ripening occurred more than two weeks earlier. The colder weather on the planting date of November 26, delayed the germination of the seeds. Also, delay in planting from October 24 to November 26 reduces plant height (8.6%), number of spikes per square meter (21.2%), biomass yield (9.6%) and increases the number of tillers per plant (35%). By changing the planting date, many environmental conditions for production will change. Following these changes, some plant characteristics effective in seed performance, including the production of flower buds, which are directly influenced by day length and day and night temperature, change in the direction of increasing or decreasing seed yield. At an earlier planting date, the length of the oat growth period increases and this plant uses more light and nutrients in the soil and therefore its height increases. The interaction effect of planting date and line was significant only on the number of days to stem elongation, number of days to maturity, 1000-seed weight and seed protein percentage. The highest percentage of seed protein was related to the bare line in planting date of November 26 and the lowest in A5 line in planting date of October 24. It seems that in earlier planting dates, the plant had more opportunity to use nutrients, especially nitrogen, while in later planting dates, due to the short growth period of the plant, there was no such possibility. As a result, seed protein has increased in earlier planting dates.

Based on the results of this experiment, L7 line can be used on November 23rd to have the highest grain yield, biomass yield and protein yield for Birjand region.

Millet is one of the drought tolerant plants that nitrogen fertilizer plays an important role in its yield. Water deficit stress as the most important abiotic stress has very adverse effects on nutrient uptake, plant growth and yield. Iran is climatically regarded as an arid and semi-arid region in the world, where the lack of precipitation and its inappropriate distribution, high temperature and extensive evaporation makes the irrigation the main way for meeting plants water demand.  Nitrogen is one of the effective factors on the development of the leaf surface and consequently the development of the shade of the plant, which improves the economic yield of the plant by increasing the leaf surface index, leaf area duration and photosynthesis. Therefore, this research was conducted in order to study the effect of irrigation regimes and nitrogen fertilizer rates on the yield and water use efficiency of millet. This research as a split plot experiment was conducted based on a randomized complete block design with three replications in research farm of Birjand branch, Islamic Azad University, Birjand, Iran in 2016. In this experiment, irrigation regim (50 and 100 percent of water requirement) as main factor and nitrogen rate (0, 50, 100, 150 kg N ha-1) as sub factor were considered. Each sub-plot consisted of 4 planting lines with a length of 5 meters and a row spacing of 30 cm and a plant spacing of 3 cm (density of 111 plants m-2). Land preparation was done with moldboard in the early spring; the tillage operation included shallow plowing, double disc plow, and full leveling. Seed millet planting was done on June 1st. Millet seeds of Peshahang variety (Pennisetum miliaceum) were used for planting. The first irrigation was done immediately after planting. After the complete establishment of the plant (four-leaf stage), irrigation treatments were applied. The water requirement was determined with the help of the FAO method and using evaporation statistics from the class A pan. The amounts of water consumed in two irrigation treatments of 50 and 100 percent of the plant's water requirement in the entire growth period were 122.9 and 210.3 liters per m2, respectively. Traits of plant height, chlorophyll index, relative water content, panicle number per m2, number of seeds per panicle, 1000-seed weight, seed yield, biological yield and water use efficiency for seed and biomass were measured. Finally, the data were analyzed by software MSTAT-C for each trait and the means were compared by Duncan Multiple Range Test at 5% level. The results showed that water deficit stress reduced the relative leaf water content by 29.4%. Under optimal irrigation conditions with increasing nitrogen application from zero to 100 kg N ha-1 chlorophyll index, plant height, number of seeds per panicle, seed yield and water use efficiency for seed significantly increased by 32.7, 20.4, 23, 35.4 and 27% respectively. Also, in optimal irrigation conditions, the application of 50 kg N ha-1, the number of panicles per m2, 1000-seed weight, biological yield and water use efficiency of biomass increased by 9.7, 26.8, 26.5 and 12.7%, respectively. In conditions of supply 50 percent of water requirement with increasing nitrogen application from zero to 50 kg N ha-1 seed yield, water use efficiency of seed and biomass significantly increased by 24.9, 17.3 and 7.7%, respectively, compared to the control. In general, the results showed that in order to achieve maximum seed yield by considering water use efficiency, optimal irrigation treatment and 100 kg N ha-1 in Birjand region can be used. In general, the results of this research showed that drought stress can lead to a significant decrease in seed yield and the efficiency of water consumption for seed production due to the inhibitory effect of stress on plant reproductive growth. Also, the lack of nitrogen (as one of the most essential nutrients for plants), in the presence of sufficient moisture, plays an important role in reducing yield and yield components and water use efficiency for seed production. However, in the conditions of water deficit stress (supply percent of water requirement), due to the disturbance in the effective absorption of applied nitrogen, the use of this fertilizer did not result in significant changes in most of the traits. Based on the results of this research, in order to achieve the maximum seed yield, taking into account the efficiency of water consumption, the optimal irrigation treatment and application of 100 kg N ha-1 can be used in Birjand region.

Plants face a variety of environmental stresses during their growth and development phase, including biotic and abiotic stress factors. Sugar beet growth and productivity are severely affected by the lack of water resources and drought, which are among the most serious environmental stressors. However, the water productivity of sugar beet can be improved by using tolerant genotypes against water scarcity. A multi-year breeding program evaluated sugar beet pollinator lines to create drought-tolerant parents. The study aimed to improve and select drought-tolerant sugar beet pollinator lines. In this regard, an experiment was conducted to evaluate the drought tolerance of sugar beet pollinator lines. The experiment was performed in two normal irrigation and drought stress conditions, in 2014. The experiment was conducted in a randomized complete block design in three replications with 20 pollinator lines and three control lines. The root yield was estimated under normal and drought stress conditions, and different stress tolerance and sensitivity indices were calculated based on the results. The obtained results showed that normal and drought stress conditions caused different responses in terms of the root yield of the lines at the 1% probability level. A considerable variation was observed among the lines in terms of the trait at the 1% probability level. Genotype-environment interaction also caused a difference in terms of root yield at the 1% probability level. This indicates that the response of lines varies according to different environmental conditions. In other words, the environment causes a change in the yield of the lines from one environment to another. Based on the ranking of the lines under normal condition and drought stress, it can be concluded that drought stress caused a decrease in the root yield of the investigated lines by a certain amount. Additionally, the ranking of the lines changed significantly under drought stress compared to normal condition. This change in the rank of the lines can indicate the presence or absence of genes that are involved in stress tolerance. Therefore, it can be acknowledged that the lines that showed a decrease in root yield under drought stress condition probably carry genes that were inherited from the drought-tolerant parent. The MP, GMP, STI, HM, YI and DI had a significant positive correlation with root yield under both conditions. Principal component analysis (PCA) of root yield in both conditions and estimated indices showed that the first two components together explain more than 99% of the variance. Based on the coefficients obtained from PCA, the first component was named as the root yield potential component and drought tolerance and the second component was named as the drought susceptibility component. Based on the MGIDI index, by applying a selection pressure of 15%, S1-950116 ranked first and control 110, and S1-950077 ranked next as the most ideal genotypes in terms of root yield, both normal and stress conditions and 11 stress tolerance and sensitivity indices.Conclission: Based on the results of correlation analysis, principal component analysis, and the MGIDI index, the MP, GMP, STI, HM, YI, and DI indices were found to be the most suitable indices for selecting lines with high root yield potential and tolerance in drought stress environments. Among the 20 studied pollinator lines, S1-950077, S1-950123, S1-950116, S1-950074, and S1-950119 had the highest tolerance compared to other lines. These lines had the highest root yield potential under both normal and stress conditions, which could be due to the presence of drought tolerance genes inherited from the tolerant maternal parent (fodder beet 7221). Therefore, these lines can be suggested as the pollinator parents for the production of drought-tolerant hybrids.

The use of low irrigation regimes by saving water consumption can help as a water management solution to increase the cultivated area and also determine the optimal cultivation pattern. The importance of oil products such as safflower has increased in recent years in the world. In general, safflower is produced in relatively dry marginal lands with low input. Efforts are being made to improve the yield and seed quality of this plant through the development of new genotypes and agricultural practices around the world. But the fact is that drought also affects the growth and performance of this plant. Zinc plays an important role in seed and biomass production, chlorophyll production, pollination process and even plant germination.

The purpose of this experiment was to investigate different levels of irrigation regime and foliar application of zinc and manganese sulfate in the research farm of Saravan Education Complex as a split plot in a randomized complete block design with three replications. The main plot included full irrigation, cut-off of irrigation at the stem stage and cut-off of irrigation at the flowering stage, and the sub-plot included three levels of foliar application with zinc sulfate (three per thousand), manganese sulfate (three per thousand) and without foliar application (control). The harvest was done manually, depending on the time of full processing, from the end of May to the beginning of June 2019. In order to evaluate the yield, the plants were harvested after removing the margins and after beating and separating the seeds, the yield was measured. The dry matter of plant leaves was also measured by collecting the leaves of three plants in each plot; Thus, by placing the collected leaves in an oven at 75°C for 48 hours and calculating the average leaf weight of three plants, the leaf dry matter was obtained. Analysis of data variance was done using SAS software (9/1 version) and mean comparisons were done at the five percent probability level using the LSD test.

The results showed that the cut-off of irrigation in the stem and flowering stages reduced number of days up to heading, number of days up to 50% flowering and the number of days up to maturity irrigation than full irrigation. Also, interruption of irrigation in stem and flowering stages compared to full irrigation conditions significantly reduced RWC and significantly increased electrolyte leakage. Foliar application with zinc sulfate compared to manganese sulfate and no foliar application caused a significant increase of 0.53 and 2.31 percent in number of days to heading, 1.71 and 2.54 percent in number of days up to 50% flowering and 0.52 and 1.64 percent number of days up to maturity, respectively. Foliar application of zinc sulfate and manganese sulfate significantly increased RWC and decreased significantly electrolyte leakage compared to no foliar application. At each level of irrigation regime, foliar application significantly increased seed yield, which was more effective in zinc sulfate treatment than manganese sulfate.

In general, full irrigation and foliar application of zinc sulfate is recommended for safflower cultivation in Saravan climate. In general, the cut-off of irrigation in the stages of stem growth and flowering caused a sharp decrease in grain yield in safflower plants compared to full irrigation conditions. Considering the high ambient temperature in the study area, it seems that the risk of under-irrigation in safflower cultivation in this area is very high and therefore it is recommended to carry out full irrigation in safflower cultivation in this area. Also, due to the alkalinity of the soil in dry areas and the non-absorbability of zinc and manganese elements by the plant and the positive effects of these elements in relation to the defense and photosynthesis system of the plant (especially zinc sulfate), foliar spraying with zinc sulfate for safflower in conditions Saravan weather is recommended.

Nutrition is one of the important factors in improving the quantity and quality of crops. Meanwhile, silicon is a useful element for rice and has positive effects on its quantitative and qualitative properties. Silicon (Si) is the 2nd and 8th extensive element on earth surface or soils and in nature, respectively. In soils, Si is mostly insoluble and not available for plants. In plants, Si-accumulation ranges from 0.1 to 10% dry weight. Plants take up Si either actively or passively in form of monosilicic acid (H4SiO4), which typically occurs in a range of 0.1–0.6 mM in soil solution. Salicylic acid, which is known as a regulator of plant growth, plays an important role in plant growth and yield, especially in conditions of environmental stress. Salicylic acid (SA) is eminent as signal molecule and phytohormone which can effectively participate in the induction of plant defense mechanisms against abiotic stress. It has the potential to regulate a number of physio-biochemical processes such as photosynthetic traits, nutrients balance, osmotic adjustments, antioxidant defense systems and improves plant protection or tolerance against drought. The external application of SA is believed to improve the adaptation to drought and osmotic stress by the generation of antioxidant enzymes activies. In order to investigate the effect of foliar application of silicon and salicylic acid on the quantitative yield and some quality characteristics of rice (Shiroodi cultivar), an experiment was conducted in the country's rice research farm (Amol). The experiment was performed as a factorial experiment in a randomized complete block design with 3 replications. Experimental treatments included foliar application of silicon from potassium silicate source at three levels of 0, 3 and 6 cc / l as the first factor and salicylic acid at four levels of 0, 0.5, 1 and 1.5 mM / l as the second factor. Sampling was done in two stages of flowering and physiological maturation. The results showed that silicon had no significant effect on grain yield and its use was only significant on grain yield components such as number of tillers and number of grains per panicle and increased them. This increase was up to the level of 3 cc silicon per liter. Meanwhile, the use of salicylic acid up to 0.5 mM caused a significant increased grain yield 17.14%. The interaction between silicon and salicylic acid had on nitrogen percentage and the content of phosphorus in seed and the highest amount of them were obtained in the treatment of 6 cc silicon, 0.5 mM salicylic acid. Leaf chlorophyll content was not affected by silicon and salicylic acid treatment but the content of leaf silicon was increased only to the level of 3 cc silicon per liter. From the results obtained in this experiment, it can be stated that the use of silicon up to the level of 6 cc of silicon per liter did not have a significant effect on the grain yield of Shiroudi variety and only on some components of grain yield such as the number of tillers per plant and the number of seeds. It had a significant effect on panicle and caused their increase. Chlorophyll, as an effective pigment in leaf photosynthesis, was not affected by silicon and salicylic acid treatment, but the amount of silicon in rice leaves was increased up to the level of 3 cc of silicon per liter. Then from the results obtained in this experiment can be stated that the use of 3 cc of silicon and 0.5 mM salicylic acid had good performance in improving grain yield and some quantitative and qualitative characteristics of rice in Shiroodi cultivar.

Conventional agriculture has altered the dynamic balance of agroecosystems by decreasing soil fertility, reducing biodiversity, and putting human and animal health at risk due to chemical residue in agricultural products. To reduce these negative environmental impacts, sustainable agricultural systems have been promoted to protect resources and biodiversity. One of the effective strategies is the integrated management of organic and chemical fertilizers in sustainable agricultural systems. Flax is an oil plant of the Linaceae family, which is extensively used in the modern pharmaceutical and food industries. Flax seeds contain protein and oil. Considering the negative effect of the excessive use of chemical fertilizers on the quality of medicinal and oil plants, most food and pharmaceutical companies prefer materials derived from sustainable and organic systems. Therefore, this study was carried out to investigate the effects of integrated application of organic and chemical fertilizers on yield components, yield, and oil content of flax.

The field experiment was laid out in 2018-2019 growing seasons at the Research field of the University of Kurdistan, Iran (longitude 47° 18' E, the latitude of 35° 19' N and 1865 m altitude). The region has a semi-arid climate according to the Köppen climate classification. The experiment was carried out in a randomized complete block design with ten treatments and three replications. The experimental treatments included control, chemical fertilizer, farmyard manure, digested fertilizer, humic acid, farmyard manure + humic acid, digested fertilizer + humic acid, chemical fertilizer + humic acid, farmyard manure + chemical fertilizer, and digested fertilizer + chemical fertilizer. Each experimental plot consisted of six rows, 4 m long and at 35 cm row spacing. The amount of manure, urea, superphosphate triple, and digested fertilizer was 10 ton/ha, 150 kg/ha, 50 Kg/ha and 4 ton/ha respectively. Fifty percent of fertilizers were applied in the integrated treatments. The concentration of humic acid was 0.5 per thousand. The site was irrigated immediately after sowing the seeds and a drip irrigation system was used once a week. Weeding was done by hand as required. Quantitative traits were measured at the maturity stage.  Seed samples were collected after the harvest process. To extract the flax oil, a Soxhlet extraction with n-hexane solvent was used. The obtained data underwent analysis of variance (ANOVA) using SAS statistical software (SAS Version 9.1), where means were compared using LSD.

The results showed that treatments had a significant effect on the most measured traits in this study. The integrated treatments significantly increased plant height, capsule number per plant, sub-branches number, biological yield, grain yield, oil percentage, and oil yield. The traits consisted of grain number per capsule, primary branches, and 1000 grain weight of flax were not affected by the treatments significantly. The highest value of biological yield (2440 kg/ha) and grain oil content (30%) was recorded in the integrated treatments of digested fertilizer + chemical fertilizer and digested fertilizer +humic acid, respectively. The integrated treatments of digested fertilizer + humic acid, farmyard manure + humic acid, chemical fertilizer + humic acid, humic acid, and digested fertilizer + chemical fertilizer significantly increased grain oil content by 36.66, 34.84, 29.63, 28.73, and 26.92 % compared to control, respectively. The highest value of grain yield (688.3 kg/ha) and oil yield (185.9 kg/ha) was obtained in the integrated treatment of humic acid + chemical fertilizer. The lowest of mentioned characteristics belonged to the control treatment. The integrated treatments of humic acid + chemical fertilizer and farmyard manure + chemical fertilizer significantly increased grain yield by 30.46 and 29.43% compared to control, respectively. The integrated treatment of chemical fertilizer + humic acid increased oil yield by 19.39, 33.69, 30.01, and 19.64 % compared to chemical fertilizer, farmyard manure, digested fertilizer, and humic acid, respectively. Environmental conditions and plant nutrition are effective factors on the growth and yield of crops. It can be said that combined treatment increased the positive effect of organic fertilizers and there were synergistic interactions between them.

The integrated treatments of organic and chemical fertilizers improved the flax characteristics compared to chemical fertilizers application singly. Overall reasonable management of fertilizers not only improved flax yield but only protected environmental safety.

Quinoa has attracted the attention of many farmers and researchers as a new crop species. This plant has a high nutritional value that is a rich source of minerals and B vitamins such as niacin, thiamin, and riboflavin. Quinoa, an annual plant with a great diversity of species, has various uses. Agricultural production has changed dramatically due to machinery, fertilizers, and chemical pesticides, while the world's population is growing even faster. Therefore, a safe and appropriate food supply to achieve food security goals needs to diversify the human food basket. So, due to the climatic richness of Iran, many plants can be introduced to the country's agricultural systems from other geographical areas. Reduced tillage is one of the most important strategies in sustainable agriculture. Reduced tillage, along with crop residue conservation and implementation of crop rotation, plays an effective role in increasing soil fertility and improving the quantitative and qualitative characteristics of the crop. The response of crop yield to tillage varies with climatic conditions and soil texture. Therefore, the most common indicator of farmers' agreement with any crop operations is crop yield. Optimal planting density per unit area provides a suitable nutritional space for a single plant and its balance in competition with other plants and ultimately achieves the highest yield. Limited data are available regarding the influence of tillage systems and planting densities on the growth and yield of quinoa under semi-arid conditions. Therefore, this study aimed to investigate the effects of tillage systems and planting densities on grain yield, yield components, and weeds of quinoa crops.

An experiment was conducted in Chardavol city of Ilam province farms in the spring and summer of 2019. This experiment was performed in split plots in a randomized complete block design with three replications. Experimental treatments including tillage as the main factor in three levels No-tillage (direct cultivation), reduced tillage (Duckfoot application and seeder cultivation), and conventional tillage (moldboard plow, disc, seeder cultivation) quinoa plant density at three levels (80, 100, and 120 plant.m2) was considered as a sub-factor. Last year, the land was cultivated with wheat. Quinoa seed was Titicaca (produced by Ilia Tejarat). The chemical fertilizer required by the plant was applied based on the soil and customary tests of the area at planting time. The chemical fertilizer used included triple superphosphate fertilizer at the rate of 50 kg/ha and urea at 100 kg/ha. Nitrogen was applied to the soil twice at planting time and 45 days after planting. Based on the soil test, there was no need for K fertilizer.

The results showed that tillage significantly affected plant height, 1000-grain weight, grain yield, biological yield, and grain quality traits (percentage of nitrogen, phosphorus, and potassium) as well as dry weight and plant density of weeds. The highest grain yield was observed in reduced tillage and conventional tillage at the rate of 2828 and 2711 kg.h-1, respectively, which showed an increase of 24.63 and 19.47%, respectively, compared to the no-tillage treatment. The results showed that planting density significantly affected plant height, 1000-grain weight, grain yield, biological yield, grain quality traits (percentage of nitrogen, phosphorus, and potassium), and dry weight and plant density of weeds. With increasing planting density, 1000-grain weight and rate of potassium and phosphorus decreased, but increasing the density from 80 to 100 plant.m2 increased grain yield from 2269.84 kg/ha to 2962.9 kg/ha. Also, increasing planting density decreased plant density and the dry weight of weeds.

This study showed that no-tillage treatment compared to the other two treatments reduced quinoa's quantitative and qualitative traits and increased dry weight and weed density. The results showed no significant difference between conventional and reduced tillage in quinoa grain yield. According to this study's results, the possibility of using reduced tillage and a density of 100 plant.m2 can be suggested for quinoa production in the study area.

Salinity is one of the major abiotic stresses that has been significantly affecting the plant growth and yield The continuous increase in salinity in arable land due to poor cultivation practices and climate change have devastating global effects, and it is estimated that about 50% of arable land will be lost by the middle of the 21st century. To date, about 1,125 million hectares of agricultural lands have already been seriously affected by salinity, thus it is considered a serious threat to agriculture. Salt stress also leads to increasing the level of ROS which results in oxidative stress, which in turn affects the plants both at cellular and metabolic levels . The plants overcome the oxidative damage through activation of antioxidants through enzymatic and non-enzymatic mechanisms. Moreover, the ROS, such as superoxide radicals ( O−2O2− ), hydrogen peroxide (H2O2), and small amounts of transition metals, also increases the concentration of OH−. Therefore, plants carry out detoxification to avoid the oxidative damage where these antioxidant enzymes play an important role. A study reported that the antioxidant enzymes positively correlate with the plant tolerance in drought and salt stress. Moreover, the higher antioxidant activities can help improving death in plants. Assessing the tolerance of crops to environmental stresses is an important factor in selecting them for cultivation in different conditions.

 In this regard evaluation and identification of wheat genotypes tolerant to salinity stress using stress tolerance indices and changes in some biochemical parameters, Experimental In completely randomized block design, with repeated three times. Factors included salinity at three levels (zero (control), 9 dS and 12 dS) and 20 genotypes of native Iranian wheat. The traits measured in this design include stress tolerance indices, protein, proline, lipoxygenase (LOX), polyethylene (TBARM), chlorophyll and carotenoids.

The results of this experiment showed that with increasing salinity stress, the amount of lipoxygenase, TBARM and carotenoids increased in all genotypes, but with increasing salinity level from 9 to 12 ds had a decreasing trend in some genotypes, however, in some genotypes, the salinity level increased with increasing salinity. Also, with increasing salinity stress, the amount of protein and proline concentration in a number of genotypes to a salinity level of 9 dS increased, but some genotypes showed a significant decrease with increasing salinity from 9 to 12 dS. Correlation analysis between indices and mean yield under normal and salinity conditions showed that all four indices are suitable for screening genotypes. Due to these indices and high yield in both environments as well as the results of biochemical properties evaluation, the best salinity tolerant genotypes were G2, G11, G86, G109, G209 and G151 genotypes.

The differences between the studied genotypes in terms of the studied traits indicate the diversity between them. The results showed that genotypes of had higher relative resistance to salinity stress than other genotypes and also the results of this study showed that the highest yield under normal conditions and salinity stress and also belong to these genotypes. High levels of proline and protein, photosynthetic capacity and LOX enzyme and low fat peroxidation also confirm this claim. Reduction malondialdehyde degradation biomarker reduced the damaging effects of oxidative stress due to salinity stress in these genotypesAlthough LOX levels were high in these genotypes, they still had good stability in salinity conditions, indicating the flexibility of these genotypes to salinity stress.Based on the obtained results and the protective role that genotypes had against salinity stress, it is speculated that these genotypes have an inherently high capacity to purify and eliminate reactive oxygen species under environmental stresses.

Plant growth and production models are great tools to study variation of irrigation and fertilizer application and those impact on plant performance. Due to the fact that applying different scenarios of fertility and irrigation in field conditions is time consuming and costly, the use of plant models is a good solution for simulating and estimating the crop yield in different conditions. The accuracy of the results obtained from the simulation models depends on the accuracy of the data required by the model and if the input data is measured and determined accurately, the model will be applicable in different conditions after calibration and validation. Due to the great effect of using different types of chemical and organic fertilizers on plant growth and yield, it is necessary to compare and evaluate changes in wheat yield using chemical and organic fertilizers in order to improve soil and water productivity. Considering the different management scenarios of fertilizer use in DSSAT application model and the role of fertility in plant performance and also that the efficiency of this model in simulating plant performance in different management scenarios of chemical and organic fertilizer application is not clear, so in this regard the efficiency of DSSAT application model In order to simulate wheat grain yield in different application of fertilizer (chemical-organic) in order to increase yield and recommendations were studied and evaluated.

This research was carried out in the research farm of Karaj Soil and Water Research Institute at 35 and 50 north latitude and 55 and 30 degrees east longitude. In terms of climate, this region is one of the hot and dry Mediterranean climates with hot and dry summers and cold winters. 4 fertilizer application treatments in a randomized complete block design in 3 replications including control, without fertilizer application (T0), application of chemical fertilizers (nitrogen, phosphorus and potassium) based on soil test (T1), application of 20 tons per hectare of waste compost with fertilizer application Chemical nitrogen at 75% and phosphorus and potassium at 50% recommended based on soil test (T2), application of 20 tons of waste compost fertilizer (T3) were considered. In this regard, 4 plots with an area of ​​200 square meters were selected and after tillage operations including plowing,  disc and land preparation, wheat was cultivated. The aim of this research was to investigate the efficiency of the DSSAT model in simulating wheat yield under different management conditions of chemical and organic fertilizer application.

Results showed that measured and simulated wheat grain yield in the control treatment (without fertilizer application) were 2.3 and 2 tons per hectare, respectively, and the corresponding measured and simulated values in chemical fertilizer application (NPK fertilizer application based on soil test) were 3.9 and 4.2 tons per hectare respectively. In terms of compost application at a rate of 20 tons per hectare, the average simulated and measured grain yield was about 3.1 and 2.9 tons per hectare, respectively. Flowering and ripening phonological time of wheat were 192 and 227 days after sowing, respectively, which is in close agreement with the simulated values, which are 190 and 230 days, respectively. RMSE, NRMSE, EF and d of DSSAT model for grain yield were 0.38, 0.13, 0.57 and 0.93, respectively, which indicates the high and appropriate performance of DSSAT(CERES) model in simulating wheat grain yield in different conditions of fertility managements based on application of chemical and organic fertilizers.

Due to the fact that applying different scenarios of fertility and irrigation in field conditions is time consuming and costly, so the use of plant models is a good solution for simulating and estimating the crop yield in different conditions. The results of the statistical indices showed that the appropriate performance of DSSAT model in simulating wheat grain yield in different conditions.

Analysis of agricultural ecosystems' sustainability is crucial for decision-making and management. Quantifying the sustainability of agroecosystems can provide solutions to achieve positive economic and environmental results. In order to meet the expanding human need for food, agricultural production techniques have become increasingly specialized. In recent years, the integration of agricultural and animal operations has been examined in order to address the challenges generated by intensive production systems. Crop and livestock production are intimately linked in integrated crop-livestock systems, resulting in favorable economic and environmental results.Emergy analysis can be used to examine the sustainability of ecological and economic systems. By adopting this strategy, we can acquire a deeper knowledge of the linkages between ecological and economic systems. Environmental and economic costs involved with achieving sustainability are quantified using Emergy analysis, allowing for the integrated control of ecological and economic issues. Emergy analysis is now utilized in agriculture to examine the viability of production systems at various scales.The goal of this study was to compare the productivity and ecological sustainability of an integrated crop and animal production system to that of a single crop production system using an emergy analysis technique.

This study was conducted in 2019 using data collected from smallholder agricultural land and livestock systems in the village of Boland, Sistan, Iran. Boland village is situated in Teymurabad village, approximately 17 kilometers north of Zabol city in the province of Sistan and Baluchistan. The agricultural composition of a Boland village includes crop production and animal husbandry.Environmental renewable and nonrenewable resources, as well as purchased resources, were used as inputs. During the study period, these data were collected via a database of agricultural organizations, verbal estimates, field measurements, and researcher observations. First, the system's boundaries are analyzed, and an energy diagram is drawn to classify the system's inputs. The second step of emergy analysis is the creation of emergy evaluation tables. After determining each system's input flow in joules, grams, or Rials, the inputs were multiplied by their transformaties to calculate the solar emjoule (sej). This study utilized specific emergy, unit emergy value, percentage of renewable emergy, emergy investment ratio, emergy yield ratio, environmental loading ratio, environmental sustainability index, emergy exchange ratio, and emergy feedback ratio.

Both the agricultural and integrated production systems in Boland Sistan village required a total of 4.41E+18 and 9.43E+18 sej/year of emergy, respectively, to maintain their functionality. Specific emergy (SpE), emergy yield ratio (EYR), emergy investment ratio (EIR), environmental loading ratio (ELR), emergy exchange ratio (EER), net profit density (NBD), and output to output ratio (O/I) all demonstrated that the integrated system generates a higher net profit than individual crop systems as a result of positive interactions between agricultural and livestock components as well as a high level of environmental sustainability. The area around Sistan is able to produce a wide variety of crops throughout the year as a result of its favorable climate and abundant natural resources. Additionally, there are several opportunities to combine cattle and crop production in this part of the world.

According to the findings of this research, integrating crop production and livestock production has the potential to lower economic risk and increase profitability, in addition to providing many benefits for the protection of soil and water resources and the productivity of the nutrient cycle. These benefits can be found in a variety of ways. As a result of this, an integrated crop production system is recommended as a suitable option for farmers to diversify agricultural operations in order to avoid hazards, improve crop production, and prevent environmental damage. This is because an integrated crop production system is a more comprehensive approach.

One of the key factors contributing to crop yield reduction is competition with weeds, which can greatly reduce the density and growth of crops. Among the most important legumes in the world, beans have become a popular substitute for animal protein and are one of the highest-producing legumes in Iran, following chickpeas. Weeds present a major challenge to maximizing bean production as they compete with beans for essential resources such as light, water, and nutrients. Additionally, weeds can impede harvesting operations and negatively impact the overall quality of the final product. In unmanaged environments, the presence of annual weeds caused a 70% reduction in the yield of white beans. Specifically, for each kilogram of dry matter comprised of annual weeds, the yield of white beans decreased by 0.38 kg per hectare. The choice of cultivar and planting date can have a significant effect on the weed population and growth in white bean fields. Different cultivars have varying levels of competitiveness with weeds, which can impact the overall weed population in the field. Similarly, the timing of planting can also affect weed growth and development. Research has shown that certain white bean cultivars, such as 'ICA Pijao' and 'Goyas', have greater competitiveness with weeds than other cultivars like 'Tacarigua'. This means that fields planted with these more competitive cultivars may experience lower weed populations compared to those planted with less competitive cultivars. Planting dates can also play a role in weed management. Early planting can allow for rapid crop establishment, which can help suppress weed growth by competing for light, nutrients, and water. However, early planting may also coincide with peak weed emergence, which can lead to increased competition between the crop and weeds. Conversely, late planting may result in slower crop establishment and reduced competitiveness with weeds, leading to higher weed populations. However, late planting may also allow for the use of pre-plant or pre-emergent herbicides, which can help to control weed populations prior to crop emergence.

An experiment was conducted at Boroujerd Research Station in 2015–2016 as a split factorial in a randomized complete block design with 4 replications to evaluate the effects of planting dates and white bean cultivars on the weed population. Planting dates (21 April, 10 May, 31 May, and 20 June), bean cultivars (Line GOYONOK98 and the Almas), and weed-free and weed-infested treatments were all investigated. Data variance analysis was done using SAS 9.4 statistical software, and graphs were drawn by Excel software. The mean comparison of the desired traits was also done by Duncan's test at the 5% probability level.

The findings revealed that delaying the planting date increased the percentage of frequency, density, and weed dominance. Pigweed (Amaranthus retroflexus L.) was the most important weed species in the experiment, with the highest frequency (85.41 percent), dominance rate (39.2 percent), and biomass (711.09 g/m2). The second planting date had the highest weed frequency (54.5 percent), which increased by 34.85, 29.61, and 19.16 percent, respectively, compared to the first, third, and fourth planting dates. Weed densities were lowest on April 20 and highest on May 30, with an average of 85.76 and 195.66 plants per m-2, respectively. A 20-day delay in planting resulted in a 46.45 percent increase in weed biomass. In addition, the first and second plantings had the lowest and highest weed biomasses, with averages of 1139.65 and 2128.35 g. m-2, respectively. According to the results of this experiment, planting an indeterminate -growth cultivar of Almas on April 21 was the best candidate for cultivation in Boroujerd due to reduced weed biomass.

The experiment's findings indicate that achieving the maximum yield of white beans is only possible when one has a good understanding of various factors such as climatic conditions, agricultural practices, and environmental stresses. Planting white beans at the beginning of May was observed to result in the lowest population and biomass of weeds due to unfavorable growth conditions for weeds like low temperature and light intensity. As a result, beans had ample growth opportunities without weed competition, resulting in considerable reductions in weeding and weed control costs and ultimately leading to the highest seed yield. In conclusion, early May planting is more advantageous than other dates regarding water resource accessibility and weed competition.

Rice (Oryza sativa) is one of the most important staple foods in the world. Currently, it is the staple food of more than 3.5 billion people, i.e., about 50% of the world population (IRRI, 2012). Puddled transplanting is the major system of rice planting in many parts of the world. This method is labor -intensive and requires a large amount of water. The Dry direct-seeded rice method, which does not need puddling and transplanting and in which the seeds are directly sown in tilled or no-tilled soil, is a feasible alternative to save water and labor. Water scarcity is the biggest challenge facing the production of agricultural products in Isfahan province, and currently more than 5,000 hectares of agricultural land are under rice cultivation. this research was carried out to investigate the effects of irrigation management on yield and water productivity in different planting methods of rice in the Lanjan region of Isfahan.

In order to investigate three rice planting methods, a field study was conducted using a split plot design based on a randomized complete block with three replications in the Lenjan region of Isfahan during 2019. The main plots included three rice planting methods Conventional flooding as a control (C1), dry seeding with drip irrigation (C2), and transplanting with integrated irrigation (C3). Two rice genotypes, Sazandegi and line No. 2, were considered sub -plots. During plant growth, the amount of irrigation water was calculated and applied based on the cumulative evaporation from the Class A evaporation pan. Using class A pan evaporation at the project site, the amount of daily evaporation was calculated by considering the relevant coefficients. The amount of irrigation water was calculated. Statistical analyses and graphs were performed using SAS and Excel software, and comparisons of means were performed using the LSD test.

The results showed that there were significant differences (5%) between genotype and planting methods in terms of grain yield and water consumption. However, the interaction between planting methods and genotypes was not significant (5%). The conventional flooding method (C1) by using 21008.3 m3.ha-1 water, which was 70% more than dry seeded with drip irrigation (C2) and 21% more than transplanting with integrated irrigation (C3), had the highest grain yield (4709.7 kg ha-1). This amount was 21% more than treatment (C2) and 37% more than treatment (C3). In treatment (C2), physical water productivity was 0.314 kg/m3, which was 29% more than in treatment (C1) and 11% more than in treatment (C3). Sazandegi used 200 m3.ha-1 water more than Line 2 and produced a higher grain yield (608 kg ha-1), while the physical water productivity of both varieties was the same.The results showed that the interaction between planting methods and genotype had a significant effect on  the number of tillers per square meter, the number of panicles per square meter, and plant height. The highest number of tillers (65) per square meter, panicle length (22.2 cm), and plant height (109.7 cm) were obtained in the conventional flooding method (C1) in Sazandegi. Also, the lowest plant height (80.5 cm in rice line No. 2) and number of tillers per square meter (41.3 and 46) were obtained in the dry seeded method with drip irrigation (C2) in Sazandegi and line No. 2, respectively, but the minimum panicle length (17.5 cm in line 2) was obtained in the transplanting method with integrated irrigation (C3).The effects of the interaction of planting methods × genotype on the number of panicles per square meter, number of grains per panicle, and 1000 grain weight were significant (1%). The means comparison showed that in the C1 treatment, the number of grains per panicle and the grain weight were higher than in C2 and C3. While the lowest number of panicles per square meter, number of grains per panicle, and 1000 grain weight were observed in C3, By reducing the amount of water consumed in the C2 and C3 treatments, the grain weight of the genotype increased compared to C1. The higher grain yield in treatment C1 can be attributed to the absence of drought stress, as well as the higher number of full grains per panicle and 1000 grain weight.

According to the results, the conventional flooding method is recommended with no water limitation. Despite the higher performance of the conventional flooding method, due to the water scarcity in Isfahan province, the dry -seeded method with drip irrigation and the Sazandegi cultivar is recommended and can be replaced in the future.

Wheat (Triticum aestivum L.) is one of the most strategic crops for food, feed, and biofuel security worldwide. Drought stress is one of the most destructive environmental stresses that limit crop productivity worldwide. Drought stress causes a wide range of physiological changes and disturbances in metabolic processes. Environmental problems caused by the use of chemical fertilizers, production costs, and consumption costs are significant issues that require methods to increase crop production and improve sufficient food for the world's population. Today, the economic damage and destructive effects of the environment due to the excessive use of chemical fertilizers in agriculture are known worldwide, and it is obvious that a suitable alternative must be found for these fertilizers. Currently, biofertilizers are used as an alternative to chemical fertilizers based on the principles of sustainable agriculture and the stress tolerance of plants. Salicylic acid is a plant growth regulator that plays an important role in the plant protection system against biotic and abiotic stresses and can affect many physiological and biochemical processes.

In order to investigate the effect of biological and chemical fertilizers and foliar application of salicylic acid on wheat tolerance to drought stress experiment, a factorial split plot in the form of a randomized complete block design in the 2019-2020 crop year in the research farm of the Faculty of Agriculture of Lorestan University in three replications was performed. The Main plot includes irrigation levels in two levels: A1: without stress (100% of water requirement) and A2: drought stress (50% of water requirement) and sub-plots including fertilizer in five levels, including B0: use of 50% chemical fertilizer, nitrogen and phosphorus fertilizer (B1: use of 100% chemical fertilizer), B2: use of nitroxin biofertilizer with 50% chemical fertilizer, B3: use of mycorrhizal with 50% chemical fertilizer, B4: use of biological fertilizers nitroxin and mycorrhiza with 50% chemical fertilizer, and foliar application treatment at two levels (C1: foliar application with water and C2: foliar application with a concentration of 1 mM salicylic acid).

The results showed that drought stress caused a decrease in grain yield, leaf chlorophyll index (SPAD), and relative water content, as well as an increase in peroxidase, proline, and electrolyte leakage. Combined treatment of biofertilizer nitroxin and mycorrhiza with 50% chemical fertilizer caused an increase of 40.53%, 5.18%, 5.89%, 13.85%, 8.46%, and 8.90%, respectively, in grain yield, leaf chlorophyll index, grain zinc concentration, peroxidase, proline, relative water content of the leaf, and 6.29 % reduction of electrolyte leakage compared to the use of 50% chemical fertilizer. Also, salicylic acid foliar spray treatment caused an increase of 11.45%, 2.82%, 4.32%, 7.46%, 9.19%, and 8.02 % in grain yield, leaf chlorophyll index, grain zinc concentration, peroxidase, proline, relative water content of the leaf, and 18.11 % reduction of electrolyte leakage compared to no foliar spraying of salicylic acid. Combined fertilizer treatments of nitroxin and mycorrhiza with 50% chemical fertilizer and salicylic acid could reduce the effect of drought stress on the traits evaluated in this research.

Fertilizer application of nitroxin and mycorrhiza with 50% chemical fertilizer and salicylic acid foliar spraying could provide favorable conditions for the growth and better performance of the plant by improving the biochemical characteristics of the plant while increasing its resistance to drought stress conditions. In general, it can be concluded that the application of biological fertilizers nitroxin and mycorrhiza with 50% of chemical fertilizers and foliar spraying of salicylic acid can be an effective and alternative fertilizer to reduce the consumption of chemical fertilizers in the conditions of drought stress in Khorram Abad in the direction of sustainable agriculture. As a result, this treatment can be recommended to farmers in order to reduce the consumption of chemical fertilizers in wheat under drought -stress conditions.

Tobacco is one of the important agricultural, industrial, and commercial plants that plays an important role in the economies of producer and consumer countries. Broomrape is an absolute parasitic plant that is attached to the roots of many important crops such as tomato, sunflower, cucumber, and tobacco. due to its lack of chlorophyll, it absorbs water and nutrients from the host plant and then reduces the growth and yield of the host plants. In the process of crop breeding, knowledge of relationships between traits is important for indirect selection of traits that are not easily measurable or that have low heritability. So far, few studies have been conducted to investigate the relationship between yield and yield components of tobacco under broomrape stress conditions. The aim of this study was to investigate the relationship between morphological traits and leaf yield (dry weight of leaf) and to determine the important traits effective in increasing the leaf yield of tobacco under normal and broomrape stress conditions.

In order to determine the most important traits affecting tobacco yield, 92 oriental tobacco genotypes were studied in a completely randomized block design with three replications in the presence and absence of broomrape during two years in the Urmia tobacco research center. The leaves of tobacco genotypes were harvested during industrial ripening and sun -cured. Characteristics such as plant height (cm), day to flowering (day), number of leaves, leaf area (square centimeters), fresh weight of leaf (g), dry weight of leaf (g), fresh weight of root (g), dry weight of root (g), and fresh and dry weight of shoot (g) were measured under normal and stressful conditions. Genotypic correlation coefficients were calculated among traits using Restricted (or residual, or reduced) maximum likelihood in SAS software. The stepwise multiple regressions were performed to identify traits affecting the leaf yield under normal and broomrape stress conditions. By path analysis based on genotypic correlation coefficients, the direct and indirect effects of traits affecting leaf yield were calculated. By path analysis based on genotypic correlation coefficients, the direct and indirect effects of traits affecting leaf yield were calculated.

Based on step-wise regression analysis, under the absence of broomrape conditions, fresh weight of leaf and leaf area were explained, and in the presence of broomrape conditions, fresh weight of leaf explained 80 and 73% of leaf yield variation, respectively. Based on path analysis, in both conditions, the fresh weight of the leaf showed the highest direct effect on leaf yield. In regression analysis for fresh weight of leaf in the absence of broomrape, aerial part fresh weight and in the presence of broomrape, aerial part fresh weight, leaf area, day to flowering, and plant height explained 61 and 72 % of fresh weight of leaf variation, respectively. In path analysis for fresh weight of leaf, in both the presence and absence of broomrape conditions, aerial part fresh weight showed the highest direct effect on fresh weight of leaf.

By comparing the results of step-wise regression and path analysis between two normal and broomrape stress conditions, it was observed that fresh weight of leaf is one of the traits that was effective on tobacco leaf yield in both conditions. In both conditions, the fresh weight of the leaf had a high and positive direct effect on leaf yield and explained a high percentage of changes in leaf yield, which shows the importance of this trait in the selection of high-yielding oriental tobacco genotypes. Of course, under normal conditions, the direct effect of the fresh weight of the leaf on tobacco leaf yield was greater than in the broomrape stress conditions. Therefore, the fresh weight of the leaf is introduced as the most important factor in both normal and broomrape stress conditions for increasing oriental tobacco leaf yield in breeding programs.

Water scarcity due to limited rainfall, high temperatures, and high evapotranspiration is one of the important factors in reducing crops and reducing the efficiency of using dry areas. Iran is one of the arid regions of the world, with an average annual rainfall of 220 mm. wheat cultivation is at serious risk of drought stress. Mycorrhizal fungi, by creating a symbiotic relationship with the roots of most crops, increase the absorption of nutrients such as phosphorus, zinc, and copper, increase water absorption, reduce the negative impact of environmental stresses, and improve the growth and yield of host plants. Therefore, considering the importance of mycorrhiza inoculation in reducing the negative effects of drought stress and improving crop yield, as well as the need to optimize the use of chemical fertilizers for sustainable agriculture, the purpose of this study was to investigate the root growth characteristics and physiological traits of different durum wheat cultivars affected by the combined application of phosphorus fertilizer and mycorrhiza under dryland conditions.

In order to evaluate the effect of mycorrhizal fungi and phosphorous fertilizer on some of the root growth characteristics and physiological traits of durum wheat in rainfed conditions, an experiment was carried out as a factorial based on a randomized complete block design with three replications at Sarableh Agricultural Research station during the growing season 2018–2019. Experiment factors consisted of four cultivars of durum wheat (Dehdasht, Zahab, Saverz, and Saji) and five levels of fertilizer source (control, 25 and 50 kgha-1 P, mycorrhizal fungi, and 25 kgha-1 P). The seeds were sown in rows four meters long and at intervals of 20 cm. The dimensions of each experimental plot were eight square meters, in which eight rows were considered, and the distance between the experimental blocks was considered one meter. Also, the amount of seed used was 120 kg/ha. To measure root-related traits in the field after pollination from a metal cylinder that was manually designed and patterned Was used. To measure the amount of photosynthetic pigment, the leaves of the five-plant flag were randomly sampled. The Analysis of variance and comparison of mean data were performed by a Duncan multi-range test using SAS 9.1 software and the drawing of figures by Excel software.

The results indicated that the application of fertilizer sources significantly improved the traits. The results also showed that the interaction of cultivars and fertilizer sources on root growth characteristics and physiological traits was significant. So that, the highest root area (61.7% increased to control treatment), root special volume (91% increased to control treatment), root tissue density (47.5% increased to control treatment), root volume density (87.1% increased to control treatment), chlorophyll a and b (86.7 and 89.04% increased to control treatment, respectively), and proline (81.9% increased to control treatment) were obtained at Saji cultivar along with application of mycorrhizal fungi + 25 kgha-1 P. The relative water content of leaves also increased in different cultivars with fertilizer application. The application of treatment mycorrhizal fungi + 25 kgha-1 P in Saverz and Saji cultivars increased the relative water content by 84% and 71%, respectively, compared to the control treatment.

According to the results, it was found that the combined application of mycorrhizal fungi with 25 kgha-1 phosphorus fertilizer compared to the control treatment had the most effect on improving and increasing the studied traits. Mycorrhizal fungi seem to increase the root system of crops, and the secretion of phosphorus-soluble organic acids causes more phosphorus uptake, which together increases the surface area and root volume and consequently increases the uptake of water and elements, Which ultimately leads to improved relative leaf water content and photosynthetic pigments. The findings of this study also showed that Saji cultivars showed a better response to mycorrhizal fungi compared to other cultivars. Therefore, according to the obtained results, the Saji cultivar with Mycorrhizal fungi + 25 kgha-1 can be recommended for cultivation under dry land conditions.

 Safflower has a special place among oilseeds compatible with the climatic conditions of Iran as a plant tolerant of drought and salinity stress and having different growth types. On the other hand, due to the fact that Iran is one of the arid and semi-arid regions with an average of one-third of global rainfall, in such areas some important stages of plant growth, including safflower, are affected by reduced soil water potential. In order to adapt the plant to stressful climatic conditions, morphological and physiological changes and the accumulation of new metabolites, along with structural changes, increase efficiency under stressful conditions. Therefore, a better understanding of the relationship between environment and genotype and the study of physiological, biochemical, and morphological traits of plants in adverse environmental conditions, especially drought stress, will lead to a better understanding of plant adaptation and events involved in drought tolerance mechanisms. Canonical correlation analysis, like other multivariate statistical methods, is a way to estimate or reduce the number of data points. This method is a generalized multiple regression mode that is used to determine the relationship between two sets of variables. In this regard, this research was conducted to better understand the relationships among different traits under drought stress and use these relationships to select more desirable cultivars.

This experiment was performed on a farm located at 5 km of Zahedan-Bam road in the Lakhshk area. This research was conducted as a split plot based on a randomized complete block design with four replications. An Experiment with three stress levels, including severe drought stress (irrigation after 250 mm of evaporation from the Class A evaporation pan surface), mild drought stress (irrigation after 175 mm of evaporation from the Class A evaporation pan surface), and normal (irrigation after 100 mm of evaporation from the Class A evaporation pan surface), was performed as the main factor, and 10 safflower cultivars were used as the sub-main factor. Drought stress started at the stem elongation stage. To measure the studied morphological and physiological traits in the experiment, sampling was performed at the grain formation stage. Before data analysis, a data normality test was performed, and after ensuring normal data distribution, analysis of variance and mean comparison by the Duncan method were performed. Due to the insignificance of the interaction of stress and cultivar in the analysis of variance of the data, canonical correlation analysis was performed for the mean of all stress levels using Statistica software.

According to the analysis of variance, the studied traits were affected by irrigation treatment, and there was a significant difference between the cultivars in terms of all studied traits under stress. This indicates the existence of high genetic diversity in terms of the mentioned traits and the possibility of selection for these traits among the studied cultivars. Also, the interaction of cultivar and stress was not significant for all traits. On the other hand, in order to investigate the relationships between traits related to drought stress tolerance in this study, canonical correlation analysis between two groups of physiological traits, including total leaf water potential, leaf relative water content, leaf osmotic potential, chlorophyll fluorescence, proline concentration, and glycine betaine concentration, and morphological traits, including plant height, plant dry weight, plant fresh weight, and number of sub-branches, was determined. The Wilkes -Lambda statistic was significant at the 1% probability level, so there was a significant correlation between physiological traits and morphological traits. In explaining the canonical function related to physiological traits, all variables except proline concentration, leaf relative water content, and leaf osmotic potential had positive coefficients. Total leaf water potential (X1) with a coefficient of 0.299 played the greatest role in justifying the first canonical variable. For canonical functions related to morphological traits, plant height had a negative coefficient, and other traits had a positive coefficient. Plant fresh weight with a coefficient of 0.987 had the greatest effect in explaining this canonical variable. On the other hand, the relative water content of the leaves, with a coefficient of -0.376, played the least role in explaining the first canonical function of physiological traits. It seems that cultivars that have higher total leaf water potential under stress conditions have higher plant fresh weight and other morphological traits (except plant height).

According to the results of the mean comparison, the Parnian cultivar was the most tolerant, and the Padideh and Zarghan cultivars were the most sensitive cultivars under drought stress. Also, based on the results obtained from canonical correlation analysis, it was found that there is a significant correlation between the pair of canonical variables resulting from physiological traits and morphological traits. There was a high correlation between total leaf water potential and the relevant canonical variable, as well as between plant fresh weight and the number of sub-branches with the relevant canonical variable; therefore, genotypes that have a higher plant fresh weight and a larger number of sub-branches have more total leaf water potential. In general, according to these results, it can be stated that more favorable morphological traits of the plant are associated with drought tolerance.