گندم نان

The Amin wheat cultivar, with the pedigree "KAUZ/LUCO-M//PVN/STAR/3/ Yaco/2*Parus/4/Pishtaz", was developed through a national irrigated bread wheat breeding program for the temperate climate of Iran. Initial and advanced crosses were conducted at the Seed and Plant Improvement Institute in Karaj, Iran, while the evaluation and selection of segregating generations (F2-F6) carried out at the Zarghan Research Station in Fars Province. Selected lines, including M-94-14, advanced to both preliminary and advanced yield trials. Under optimal irrigation conditions in temperate climate adaptation trials, the M-94-14 line (Amin cultivar) achieved an average grain yield of 6950 kgha-1, representing a 3.9% and 5.7% yield advantage over the control cultivars Parsi and Baharan, which yielded 6688 and 6574 kgha-1, respectively. This line exhibited desirable baking quality traits, including favorable grain protein content, Zeleny sedimentation volume, bread loaf volume, grain hardness index, and SDS sedimentation height. Additionally, it demonstrated acceptable resistance to yellow and leaf rusts. On-farm trials across various regions showed that the Amin cultivar achieved a grain yield of 6820 kgha-1 under optimal irrigation conditions, outperforming the average grain yield of control cultivars, which was 6609 kgha-1. Given the superior performance of this line compared to existing cultivars in temperate climate of Iran, the M-94-14 line was officially released as the Amin cultivar in 2019.

Cereals are considered to be among the most important sources of human energy, among which bread wheat is recognized as an important and strategic crop in the world. Currently, developing drought-tolerant cultivars is counted a major challenge for breeders. Various methods are used to assess diversity in plant species, including multivariate statistical approaches. This study aimed to evaluate genetic diversity and select the most promising lines for improvement programs in rain-fed conditions.  

The experiment was conducted during the 2022–23 agricultural year at the Shirvan Rain-fed Agricultural Research Station- North Khorasan. In this research, 193 lines and seven rain-fed wheat cultivars were evaluated using an alpha lattice design with two replications. Data on phonological and morphological traits were collected during the growing season and after harvest. Statistical analyses were performed using SAS software version 9.4. Correlation analysis, stepwise regression, and principal component analysis (PCA) were conducted using R software (version 4.2.1). The Ideal Genotype Selection Index (SIIG) was calculated in Excel to identify the best-performing lines. 

Analysis of variance revealed significant differences among genotypes for all studied traits (p<0.01). Seed yield showed the strongest positive and significant correlations with biological yield (0.824), harvest index (0.817), plant height (0.393), spike weight (0.236), and thousand-kernel weight (0.221) (p<0.01). ). In contrast, an inverse relationship was observed between phonological traits (e.g., days to maturity, heading, and anthesis) and morphological traits (e.g., harvest index and thousand-kernel weight), suggesting that late-maturing genotypes tended to have lower seed weight and yield. The results of PCA indicated that the first three principal components accounted for 69.1% of the total variation among traits. Based on the SIIG index, genotypes 25, 73, 90, 84 and 190 were identified as the most ideal lines, with SIIG values of 0.91, 0.83, 0.83, 0.81 and 0.80 respectively. The correlation between the SIIG index and the evaluated traits showed that grain yield, biological yield, and harvest index had a high correlation with the SIIG index. Therefore, genotypes 25, 73, 90, 84 and 190 with high SIIG index and high yield potential, can be used in future breeding programs.

Stripe (yellow) rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most important diseases of wheat in many parts of the world. The annual and indiscriminate use of fungicides not only increases pollution but can also lead to the resistance of pathogenic fungi to these chemicals. Therefore, creating genetic resistance is the best way to deal with this disease. Due to the challenges in quickly replacing susceptible wheat cultivars, breeding cultivars with suitable levels of genetic resistance is the most efficient method to control stripe rust as a long-term strategy. In this study, the Yr18 and Yr29 genes, which are among the most effective resistance genes in adult plants, were transferred to the Iranian cultivars Baharan, Rakhshan, Parsi, and Amin using the marker-assisted backcrossing method. For each cultivar, in four separate breeding projects, crosses were made with the donor parents Pavon/Lalbahadur and Opata85. The progeny of this generation (F1), containing 50% of the genetic material of their recurrent parent, were backcrossed with the Iranian cultivars (recurrent parent) to obtain BC1F1 progeny in each population. By genotyping 30 random plants in each project, the heterozygous genotypes carrying the resistance genes were identified using specific markers, and the second backcrossing was performed. In each population, a line resistant to yellow rust can be created by repeating several generations of backcrossing and one generation of selfing.

This study aimed to investigate the effect of sowing date and enviromental factors during different growth stages on some phenological characterisitcs and grain yield of commercial bread wheat cultivars. The experiment was carried out as split-plot arrangements in randomized complete block design with three replications at the Darab reaesrch field station in 2018-19 and 2019-20 cropping cycles. Five sowing dates: October 27, 11, and November 26, December 11, and 26, were assigned to the main plots. Five commercial wheat cultivars: Mehregan, Barat, Khalil, Sarang, and Setareh, were randomized in the subplots. Results showed that the late maturity cultivars, Khalil and Brat, had higher grain yield in earlier sowing dates. Early maturity cultivars, Setareh and Mehregan, had less yield reduction in later sowing dates. The highest and lowest mean grain yield obtained from November 11 (6934 Kg ha-1) and December 26 (5775 kg ha-1), respectively. Number of days and required growing degree-days (GDD) decreased with delaying sowing date. The decrease of required GDD to reach commencement of stem elongation, anthesis and maturity stages from the first to fifth sowing date was 181, 282 and 528 GDD, respectively. Simultaneous effect of weather variables and sowing date on some characteristics revealed that the first two components explained approximately 41% of total variation. Results showed that temperature was the most important factor controlling the phenological stages duration. Despite the importance of temperature, changes in sowing date can alter the required GDD for phenological stages due to other environmental factors. In general, the results of this study can provide an insight into bread wheat cultivars responses to different climatic conditions and development of new bread wheat cultivars adapted to target environments.

Bread Wheat is the most extensively cultivated wheat and one of the four major crops in the world that constitutes the principal food of more than 30% of the world population. Biotic and abiotic environmental stressors are major factors limiting plant growth and productivity, which play a significant role in determining the yield and production potential of plants by affecting morphological, physiological, biochemical, and molecular processes. Among the abiotic stresses, the deficiency of micronutrients in the soil is important. Micronutrients regulate food metabolism in humans, and their deficiency endangers human health. Iron and zinc are essential micronutrients for human health and cofactors of many vital enzymes involved in many human metabolic processes. In plants, iron is the most required element among all micronutrients. It is a part of the catalytic group of many oxidation and reduction enzymes and is required for chlorophyll synthesis. To facilitate the adequate uptake and prevent excessive absorption of iron, plants have developed a balanced network to regulate the uptake, use, and storage of ions. In fact, such adjustment processes depend on genes that regulate ion homeostasis in plants. Due to the existence of a large allohexaploid genome and technical challenges in wheat transformation, few genes involved in iron and zinc uptake, transfer, and storage have been characterized functionally. Considering the important role of ZIP proteins in iron uptake efficiency, investigating the expression of the ZIP genes in Fe-efficient and -inefficient bread wheat cultivars can be effective in improving Fe-efficient cultivars in this valuable crop. Therefore, this research aimed to evaluate the expression of ZIP3, ZIP6, and ZIP7 genes in the leaves and roots of two Fe-efficient and -inefficient bread wheat cultivars at different growth stages under iron deficiency stress.

This research was carried out in a completely randomized design (CRD) based on a factorial experiment with three replications in the research greenhouse of the Faculty of Agriculture, Urmia University. The first factor was two Fe-efficient (Pishtaz) and -inefficient (Flat) bread wheat cultivars, the second factor was two soil iron levels (iron deficiency and sufficiency, respectively, 1.4 and 10 mg/kg of soil), and the third factor was two sampling stages (vegetative and reproductive, respectively, one month after planting and 30% heading). To evaluate the expression of genes, the roots and leaves of the plants were sampled at each growth stage. The seeds were obtained from the Iranian Seed and Plant Improvement Institute, disinfected with 1% hydrogen peroxide, and planted at a depth of 4 cm in the soil. The plants were irrigated using distilled water to the extent of field capacity during the growing period.

The results of variance analysis of the relative expression of all three studied genes showed that the interaction effect of cultivar × organ × sampling stage was significant at the probability level of 1%. The comparison of the means for the cultivar × organ × sampling stage interaction effect revealed the highest ZIP3 expression in the roots of the Fe-efficient cultivar (Pishtaz) in the vegetative and reproductive stages. The relative expression of this gene was higher in the roots of the Fe-inefficient cultivar (Falat) than that of the Fe-efficient cultivar (Pishtaz). However, the Fe-inefficient cultivar (Falat) showed the highest relative expression increase in the leaf in both reproductive and vegetative stages, but the difference in the gene expression level in the leaf between the two growth stages was not statistically significant. The lowest gene expression level in the leaf belonged to the Pishtaz cultivar. The comparison of the means of cultivar × organ × sampling stage for the ZIP6 gene indicated an increase in the relative expression of this gene in the roots of the Fe-efficient (Pishtaz) and -inefficient (Falat) varieties in the vegetative and reproductive stages, respectively. The comparison of the means of cultivar × organ × sampling stage for the ZIP7 gene indicated the highest relative expression of this gene in the roots of the Fe-efficient cultivar (Pishtaz) at the vegetative stage. The relative expression level of this gene in the root of the Fe-efficient variety in the vegetative stage was significantly higher than that in the reproductive stage. In both vegetative and reproductive stages in the leaf, the increase in gene expression was higher in the Fe-inefficient cultivar.

The increased ZIP3 expression in iron deficiency conditions in the roots of the Fe-efficient cultivar at the vegetative stage demonstrates the possible role of this gene in Fe uptake from the soil and its transfer to the aerial parts of the plant in the early growth phase. The ZIP6 gene `was expressed in both roots and leaves throughout the entire growth period of the plant. However, the expression level of this gene increased with the age of the plant. Therefore, the ZIP6 gene is probably responsible for Fe uptake and transport to different organs throughout the entire growth period of the plant and plays an important role in preserving iron in iron deficiency conditions. The ZIP7 gene is expressed in both leaves and roots in iron deficiency conditions, but the level of expression is higher in the roots of the Fe-efficient variety during the vegetative stage. This gene may be involved in iron uptake from the soil and its transfer to aerial organs.

The germination stage in plants, including wheat, is an extremely susceptible stage to biotic and abiotic stresses. Plant establishment the in the early stages of growth, especially in the germination stage, is always notably important. Salinity stress is one of the abiotic stresses that cause much damage annually, especially in arid and semi-arid regions. Therefore, identification and use of cultivars tolerant to salinity stress is one of the effective ways to reduce the negative effects of salinity stress.

In the present study, response of 64 spring wheat cultivars during the germination stage at two levels of salinity stress (zero as a control and 12 dS/m of sodium chloride) was investigated in the form of a simple lattice design with two replications at the Genetics Laboratory of the Faculty of Agriculture, Urmia University. During seven days, germination percentage, germination index, germination rate, germination energy, seedling vigor, mean germination time, and mean germination rate, and after the seventh day, seedling length, shoot length, root length, ratio of shoot length to root length, seedling fresh weight, and seedling dry weight were measured.

Among the studied cultivars, a statistically significant difference was observed at the probability level of 1% in terms of all traits including radicle length, shoot length, seedling length, fresh weight, dry weight, radicle to shoot length ratio, germination index, germination rate, germination energy, germination percentage, seedling vigor, mean germination time, and mean germination rate. Based on the results of factor analysis, under both normal conditions and salinity stress, the studied traits were grouped into four main factors, and these four factors explained 92.74% of the changes under normal and 93.85% under salinity stress conditions. Using cluster analysis, cultivars were grouped into three and two clusters under normal and salinity stress conditions, respectively.

Based on the results of bi-plot obtained from factor and cluster analyses, the cultivars Moghan 2, Bistun, Akbari, Moghan 3, Dastjardi, Marvdasht, Gahar, and Mahdavi are the preferred cultivars and the cultivars Darya, Bam, Tajan, Sistan, Frontana, Kavir, and Afogh were introduced as undesirable cultivars in terms of the traits measured in this experiment, which can be used in breeding projects.

In arid and semi-arid regions, biotic and abiotic stresses can directly or indirectly lead to restrictions and decreased growth of different plants. In these areas, salinity stress is one of the major challenges facing agriculture and crop production that causes huge damage to crop yields annually. The amount of salinity in the soil results in plant growth limitation, and increased soil salinity disrupts water and essential nutrient absorption for the plant and reduces plant growth, which can then lead to plant death. Reduced root growth and development, decreased nutrient absorption, increased likelihood of allergies to diseases and pests, decreased yield, and final product quality (e.g., nutrient deficiency), and increased toxic elements, are among the negative effects of salinity on plants. Various factors are involved in the creation of salinity, the most important of which can be climate change, source rock weathering, improper irrigation, drought, excessive consumption of fertilizers, and reduced seawater levels. Following climate change, these damages are on the rise every year. Due to the increase in population growth, demand for food production is increasing day by day. Wheat is known as the major grain in the supply of nutritional needs in the world, hence its sustainable production is of paramount importance. Salinity is recognized as an important factor in reducing wheat yield, and it may increase the accumulation of harmful salts in the plant tissue, which can lead to physiological damage and decreased plant growth. The effects of soil salinity vary depending on the amount of salinity, the type of salinity, and the type of wheat. One way to prevent the negative effects of salinity is to use salinity-resistant wheat cultivars. The range of diversity in relation to salt stress tolerance in different plants, especially the wheat plant, depends on various factors such as plant genotype, duration of stress, and plant growth stage. The seedling stage in wheat is one of the important stages regarding tolerance to salt stress. This study aims to investigate the response of spring wheat cultivars in the seedling stage to salinity stress.

In the present study, the reaction of 64 Iranian spring wheat genotypes at the seedling stage under normal conditions and 12 dS/m salinity stress was investigated in two replications in a simple lattice design at the research greenhouse of the Faculty of Agriculture, Urmia University in 2021-2022. In this study, in the four-leaf stage, salinity stress was applied gradually for two days. The measured traits were chlorophyll (SPAD), canopy temperature, shoot length (SL), root length (RL), seedling length (PL), shoot potassium content (KS) ), root potassium content (KR), shoot sodium content (NaS), root sodium content (NaR), shoot potassium to sodium ratio (KNaS), root potassium to sodium ratio (KNaR), root volume (RV), leaf area index (LAI), radicle fresh weight (FWR), radicle dry weight (DWR), relative leaf water content (RWC), shoot fresh weight (FWS), shoot dry weight (DWS), seedling fresh weight (FWP), weight dry matter of seedlings (DWP). The data of the studied traits were obtained in a random complete block design. PROC GLM was used for the analysis of variance (ANOVA) in SAS 9.4 software. The correlation was examined using PROC CORR and decomposition into factors using PROC FACTOR. The figures were grouped using the gplots software package and the biplot diagram was drawn with the factoextra software package in the R 4.1 environment. The MANOVA statement in PROC GLM was used in SAS 9.4 software for multivariate variance analysis.

Based on the results of ANOVA, statistically significant differences were observed between the tested cultivars based on the traits studied in the seedling stage, including FWP, DWP, FWR, DWR, FWS, RWS, and (PL). In both normal and salt stress conditions, DWP showed the most significant correlation with FWP, DWS, and DWR. Under the salinity stress conditions, FWS was significantly correlated with DWS, FWP, and DWP. Based on factor analysis, the studied traits in both normal and salinity stress conditions were grouped into seven factors, which explained 77.93% and 76.44% of the total changes in normal and salinity stress conditions, respectively. Using cluster analysis, cultivars under both normal and salt stress conditions were grouped into three clusters.

Based on the biplot results of factor analysis and cluster analysis, Maron, Darya, Shiroodi, Moghan 3, Darab 2, Roshan, Pishgam, and Pishtaz cultivars are introduced as favorable cultivars. Chamran, Bam, Alborz, and Maroodasht cultivars are categorized as unfavorable cultivars that can be used in further wheat breeding programs.

Breeding experiments initiated with the examination of segregating generations serve as a significant source for creating genetic diversity, continuing with comparing genotypes in preliminary, advanced, and adaptability performance trials. Superior lines require further investigation under real farm conditions. Selected lines, along with common regional varieties, were assessed in performance comparison experiments, categorized as On-farm trials. These comparisons aim to evaluate new lines against traditional varieties concerning higher grain yield, disease resistance, early maturity, and lower water consumption outside of the research station areas. Additionally, conducting these trials on farmers' fields enhances the awareness of farmers, experts, and extension agents regarding the characteristics of new lines. This study aimed to compare the agronomic and quality traits of three promising bread wheat lines (S-98-7, S-98-11, and S-98-22) with the local control variety Merghan in the warm climates of Fasa and Darab during the cropping season 2022-2023. The seed rate was set at 400 seeds per square meter (equivalent to 180 kg per hectare) over 2000 square meters. Data on days to germination, spike emergence, physiological maturity, number of grains per spike, number of spikes per square meter, sensitive to shedding, plant height, lodging, grain yield, thousand-grain weight, and major plant diseases (yellow rust, stem rust, brown rust, septoria leaf blotch, and septoria strip blotch) were recorded. Quality traits related to baking (protein content, Zeleny mix volume, hardness index, wet gluten percentage, gluten index, SDS sedimentation, and hectoliter weight) were analyzed to examine the nutritional value. Results indicated no significant differences in the number of days to physiological maturity among the tested genotypes. Based on the results from Darab, Fasa, and the average of both experiments, Line S-98-22 yielded the highest grain production (10,006; 9,880; and 9,943 kg per hectare, respectively) compared to the control yield (Darab: 9,947 kg per hectare, Fasa: 8,571 kg per hectare, and average of both regions: 9,259 kg per hectare). Observations in both regions indicated no lodging or the presence of leaf blotch diseases (septoria leaf blotch, bacterial strip blotch, yellow rust, brown rust, and stem rust), with only 5% yellow rust reported in the control variety in the Fasa trial and 5% lodging in the control variety in the Darab trial. Ultimately, the Selection Index of Ideal Genotype Index (SIIG) identified Line S-98-22 as the best line based on the evaluated traits across both regions. Regarding quality traits, Line S-98-22 exhibited the highest wet gluten, gluten index, protein content, and suitable Zeleny volume, indicating the best baking quality. Other genotypes also fell within the range of desirable baking quality genotypes. Given its favorable agronomic traits, including high grain yield and drought stress tolerance at the end of the season, along with quality characteristics, Line S-98-22 can be introduced as a new bread wheat variety for warm and dry regions.

Salinity stress is one of the most limiting non-living factors in wheat production. To overcome this problem, helpful information can be provided by understanding how genes respond and act in stress, to help plants withstand environmental stress. The biochemical and molecular response of wheat to salinity stress is diverse. Considering the effective role of the important family of transcription factors NAC and WRKY in dealing with stresses, this study evaluated the expression levels of three important genes from these families, TaWRKY10, TaWRKY53, and NAC2, as well as the content of chlorophyll, malondialdehyde, catalase, and polyphenol oxidase enzymes in bread wheat cultivars (Kalateh, Baharan, and Gonbad). The experiment was conducted in a randomized complete block design with four replications in greenhouse conditions. The main factor was salinity treatment (control, 9 and 12 deci-siemens) applied through irrigation after germination and plant establishment. The secondary factor was wheat varieties (Kalate, Gonbad, and Baharan). Sampling was performed to evaluate gene expression and biochemical traits. Real-Time PCR technique was used to check gene expression. In all tested cultivars, the chlorophyll content decreased with increasing salinity. The highest amounts of chlorophyll a and b were observed in the control treatment of the Kalate variety (14.5 and 18.2 mg/g fresh weight, respectively). Catalase and polyphenol oxidase enzymes, as well as the expression of TaWRKY10, TaWRKY53, and NAC2 genes, increased with salinity compared to the control in all three cultivars. The highest enzyme levels were observed in 12 deci-siemens salinity treatment of the Kalateh variety. The highest malondialdehyde amount (31 μmol/g fresh weight) was observed in the Baharan cultivar under 12 deci-siemens salt stress, indicating greater cell membrane damage in this cultivar. Based on the results, the Kalateh variety showed greater tolerance to salt stress compared to Baharan and Gonbad varieties. Transcription factors play a crucial role in enhancing plant resistance to salinity. The results of this study confirm the role of transcription factors in salinity resistance and could be utilized in developing and introducing tolerant wheat cultivars.

As one of the most important cereals, bread wheat is an essential part of food security in the world, which supplies one-fifth of the total calories of the world population. Nowadays, the yield of wheat has been affected by climate change-driven drought as one of the most important abiotic stresses that has become an important threat to food security in the world. Root and stomatal traits are especially important in breeding plants to withstand drought stress. Stomata play a key role in controlling carbon dioxide uptake and water loss through transpiration. Therefore, stomatal characteristics are used as indicators of water status and plant growth, especially in drought stress conditions. Having a wide range of physiological and morphological characteristics, roots play an essential role in absorbing water and nutrients. They are also the first organ that sends signals to control the stomata in response to dryness. Therefore, the difference in the structure of the root system can cause the difference between the performance in different cultivars. This study was conducted to investigate stomatal characteristics and their relationship with the root system and plant performance in 24 bread wheat lines and cultivars.

To investigate the relationship between stomatal dimensions and density with the root system, an experiment was conducted on 24 bread wheat genotypes in the form of a randomized complete block design with three replications in the rainfed conditions of the research farm at Zanjan University Faculty of Agriculture in the crop year 2018-2019. In this experiment, PVC pipes were used to study the root system. Twelve seeds were planted in each tube, which were thinned to seven after germination. In each experimental unit, there were two tubes for each genotype, one of which was used to evaluate traits and final yield, and the second tube was used for root studies. Stomatal traits, including the length and width of stomata and number of stomata per unit area, root traits including root length, root diameter, root volume, root surface, and root biomass, and seed yield were measured in the end. The resulting data from the measured traits were analyzed in the form of a randomized complete block design, and the averages were compared using the LSD method. The data were analyzed using multivariate statistical analyses, including regression analysis, path analysis, and factor analysis, and cluster analysis was used to group genotypes. Statistical calculations were done using SAS 9.0 and SPSS 21 software.

The results of analysis of variance and mean comparison showed high variability among genotypes for all measured traits. The results of the mean comparison of genotypes showed that genotypes 2, 5, 8, and 16 had the highest yield, and genotype 23 had the lowest yield among the examined genotypes. The highest number of stomata on the upper and lower leaf surfaces belonged to genotypes 5 and 2. In terms of root traits, the highest diameter, volume, length, root surface, and root dry weight at a depth of 0-25 cm were recorded for genotypes 2, 3, 18, and 5, respectively. There was a high and significant correlation between the yield and the number of stomata on the upper and lower leaf surfaces, the length and width of  the stomata on the upper leaf surface, diameter, volume, dry weight, and root surface at a depth of 0-25 cm in the soil. Based on the results of stepwise regression analysis, two variables, the number of stomata on the lower leaf surface and root dry weight at a depth of more than 25 cm explained 91.4% of the changes in grain yield. According to the results of the causality analysis of the number of stomata on the lower leaf surface, the most direct effect had a positive effect on seed yield. The results of factor analysis grouped the studied traits into three factors with 82.48% variability justification. The shares of the first, second, and third factors to explaining data changes were 48.86%, 24.62%, and 8.99%, respectively. Based on the plot obtained from factor analysis, genotypes 2, 5, 8, and 16 had high values for the first and second factors. According to the coefficients of the factors, it can be claimed that the genotypes located in this area have high performance, a high number of stomata, and strong root traits, which were found at the soil depth of 0-25 cm. For this reason, these are the genotypes that could produce high yields by absorbing water from the surface layers of the soil by having a large number of stomata and carrying out more photosynthesis. Moreover, the investigated genotypes were divided into three groups from cluster analysis by the ward method and Euclidean distance. Genotypes 2, 5, 8, and 16 were placed in the first group and had the highest mean values for grain yield traits, number and width of stomata on the upper and lower leaf surfaces, and root traits including diameter, volume, and dry weight at a soil depth of 0-25 cm, and root diameter at a depth greater than 25 cm. The lowest values for stomatal length were observed in both leaf surfaces. These were the best genotypes for cultivation in dry conditions.

A strong superficial root system can provide the plant with water from scattered rains that occur with low frequency at the end of the growth period. On the other hand, the increase in the number of stomata along with their smaller size reduces leaf pores and enables a faster response of the stomata, and the rapid response of the stomata maximizes water use efficiency. Therefore, having a strong superficial root system along with high stomatal density can increase seed yield in dry conditions.

 Drought is one of the most important global threats to food production, in addition to that, climate change and the increase in the global population also widen the dimensions of this problem. One of the ways to solve this problem is to create new cultivars with greater tolerance to drought stress. Wheat has been one of the most important sources of human food all over the world and it is used in various food products and processing industries. Wheat together with rice and corn provide more than 60% of calories and protein needed for human nutrition. In areas like Iran, where most of the rain occurs in winter and early spring, wheat will face water shortage and drought stress at the end of the growing season. In crops, one of the effective methods that can minimize the effect of this phenomenon in combination with other methods of water deficit management is the use of high-yielding and drought-tolerant cultivars. Despite the numerous scientific sources published in this field, there are still many gaps in these studies, so studying the effects of drought stress is always a research priority. Ilam province, as one of the irrigated wheat production areas, suffers from the lack of cultivars that are resistant or tolerant to low irrigation conditions, so investigating the response of different wheat genotypes in low irrigation conditions as low input production systems is very important and is addressed in this study. 

In order to evaluate some bread wheat genotypes under normal and drought stress co ditions, 36 wheat genotypes were evaluated in the form of a randomized complete block design in three replicates in the crop year of 2019-2019 in Darehshahr city located in Ilam province. The examined traits include spike length, spike number per plant, spike length, peduncle length, sub-peduncle axis, flag leaf length, flag leaf width, number of stem nodes, plant height, number of spikes per plant, number of seeds per spike, number of seeds per plant. plant, number of tillers, hundred seed weight, single plant seed weight and seed yield. Based on performance under stress (Yp) and normal (Ys), drought tolerance indices such as average productivity tolerance index, harmonic mean, geometric meanproductivity (GMP), stress sensitivity index, stress tolerance index, performance stability index (YSI) and Relative Stability Index (RSI) and Performance Index (YI) were calculated. The mean comparison test was performed using Duncan's method and using R software. Simple correlation (Pearson), decomposition into components, decomposition into factors were also performed between the tested traits. SAS 9.1 statistical software was used for statistical analysis of traits. 

The results of the analysis of variance in drought and normal stress conditions showed that there was a significant difference between genotypes in all traits at the probability level of 1%. The most important significant correlation coefficient in both conditions between seed yield was related to the seed weight of a single plant and the number of seeds per plant. Considering the high and significant correlation of grain yield under stress and non-stress conditions with drought tolerance indices, higher productivity indices, geometric mean productivity (GMP), geometric mean  and stress tolerance index  as the best indicators. were chosen. It seems that in order to evaluate stress tolerance, the selection of genotypes should be based on several indicators. Factor analysis at the drougth stress condition indicated that the two first factors expalined a total of 97. 57% of the variance. The first factor was called the performance stability factor and the second factor was named theStability Factor. The biplot diagram also showed that the genotypes of no. 13 and 47 were placed in the vicinity of the ranges related to drought resistance indices (STI, MP, GMP, and HM) and were introduced as superior genotypes. 

According to the data obtained from analysis of variance in both normal and drought stress conditions, the genotypes were significant in terms of all traits. The significance of the studied traits indicates the existence of diversity between genotypes in terms of the studied traits, and some of these traits can be used to evaluate stress tolerance. The best genotypes had the best averages for peduncle length of genotype 33, for the number of seeds per plant of genotype 5, for seed weight of a single plant and seed yield of genotype 1. The heat map shows the relationship between drought tolerance based on different yield and drought stress toleranceindices. Considering the high and significant correlation of grain yield under stress and non-stress conditions with drought tolerance indices, average productivity indices, GMP, geometric mean and stress tolerance index were selected as the best indices that are able to distinguish tolerant genotypes from other Screen the genotypes. The yield index (YI) had the highest correlation coefficient with grain yield under stress conditions. Based on biplot results, genotypes No. 13 and 47 were the most tolerant genotypes under drought stress conditions more than other genotypes and were introduced as superior genotypes.

Branding of commercial bread wheat cultivars for producing baking products with uniform and acceptable quality by cconsumers is related to sufficient knowledge of different environmental conditions of whaet growing areas in Iran, as well as baking quality properties of grain and dough. Therefore, the aim of this research wwas to investigate grain and dough rheological quality properties including quantity and quality of protein and gluten of the grain samples as well as farinograph and extensograph characteristics and grouping based on various products in the baking industry of 22 irrigated commercial bread wheat cultivars collected from 30 provinces in Iran in 2015-2016. The results showed that the highest and lowest grain protein content was recorded for cv. Mehregan and cv. Uroum with 12.7% and 11.4%, respectively. The wet gluten varied from 20.5% (cv. Sisatan) to 30.9% (cv. Gonbad), zeleny sedimentation value ranged from 18.9 ml (cv. Arg) to 25.5 ml (cv. Mehregan), and SDS sedimentation height varied from 51.3 mm (cv. Sivand) 69.6 mm (cv. Mehregan). The dough prepared from cv. Mehregan (15.5 minutes), Soissons (10.3 minutes) and Chamran 2 (10.1 minutes) showed high dough stability, respectively. The lowest dough stability, among the examined cultivars, was related to cv. Uroum (1.3 minutes) and Sistan (0.2 minutes), respectively. Similar results were observed in extensograph test, cv. Mehregan and cv. Soissons were identified as semi-strong, while cv. Uroum, cv. Ehsan and cv. Heydari had the lowest dough energy. Finally, according to the results of this research some characteristics as growth habit, grain colour, grain hardness, grain protein content, farinograph and extensograph, the studied irrigated commercial bread wheat cultivars were grouped based on end-use products, in four groups, Voluminous breads (industrial breads) and suitable for blending with weaker flours, semi-voluminous breads, flat breads (Iranian breads) and confectionary, cakes, cookies and related industries.

In crop season 2012-2013 wheat genotype "Frncln/Rolf07" was introduced to Iran within an international nursery received from CIMMYT and was studied in experiment of evaluation of yield and agronomic characteristics of spring wheat genotypes in international nurseries in temperate regions. Then in 2013-2014 crop season, it was selected in a preliminary regional wheat yield trial under normal irrigation with an average yield of 8114 kgha-1 compared to the check cultivars Parsi, Sirvan, Pishtaz and sivand, respectively, with grain yield of 8.035, 8.022, 6.914 and 7.985 kgha-1. This cultivar was further investigated in the advanced regional wheat yield trial of temperate regions of the country during 2014-2015 and with average grain yield of 7093 kgha-1 compared to 6495 and 6423 kgha-1 yield of check cultivars Parsi and Sirvan, respectively, and was selected for adaptation evaluation. The average yield of M-94-15 line in temperate climate adaptation experiment during the 2015-2017 crop season under normal conditions was 7231 kgha-1 verses 6688 kgha-1 of Parsi cultivar and 6574 kgha-1 of Baharan cultivar and in general, total mean grain yield was 3% higher than the average of whole genotypes. Due to the good condition of M-94-15 line reaction to stripe rust (O-30MR) and leaf rust (O-30MSS) diseases, as well as the resistance to grain shattering and good bread making quality, this line was selected for study at the level of farmers' fields. Wheat line M-94-15 based on its favorable agronomic characteristics, suitable earliness and good bread making quality was released in 2019 as Farin for cultivation in temperate agro-climatic regions.

In order to compare 25 genotypes of bread wheat in terms of morpho-physiological and biochemical traits, an experiment was conducted in a randomized complete blocks design with three replications in the rainfed and irrigated conditions at Razi University, Iran, in 2016-2017. GT-biplot was used to evaluate genetic diversity and to identify stable genotypes with high yield and drought tolerance. Combined variance analysis showed that there was high variability among genotypes for the most of traits. Examining the correlation of traits in two environmental conditions showed that morpho-physiological traits; especially yield components, were the most related to yield. The results of the GT-biplot method showed that the first and second principal components explain 41.7% and 40.1% of the total changes in rainfed and irrigated conditions, respectively. Based on the GT-biplot analysis diagrams of genotypes 10, 15, 6, 13, 2, 14, and the Pishtaz cultivar in terms of physiological traits, yield and its components and the traits related to stem and spike in irrigated conditions, and genotypes 10, 15, 6, 18, and 17 in terms of biochemical traits, yield and its components, and traits related to stem and spike in rainfed conditions were recognized as superior genotypes. The genotypes 2 and 6 in irrigated conditions and the genotype 6 in rainfed conditions had the lowest genotype×trait interaction. Finally, the genotypes 10, 15, and 6 were superior in two environmental conditions and the genotype 6 had the least interaction effect in both conditions. Therefore, these genotypes can be used in breeding programs.

Salinity impacts on crop production is further increasing as the global demand for food means agriculture extends into naturally salt-affected lands. Chlorophyll retention and the low sodium traits were associated with salt tolerance in wheat and barley under salinity conditions. Saline soils limit plant growth due to osmotic stress, ionic toxicity, and a reduced ability to take up essential minerals. Barley and wheat have different salt tolerances capacities and are grown as major grain crops in both saline and non-saline soils. The net sodium uptake for a plant growing in 150mM NaCl with perfect osmotic adjustment is similar to actual rates measured for wheat and barley. Our hypothesis is that salinity reduces the growth of wheat more than barley by reducing chlorophyll content. The aims of this study were to analyse the effects of salinity on the growth and yield of barley and wheat cultivars to explore the links between the sodium accumulation and chlorophyll content.

Tow bread wheat cultivars differing in salt tolerance (Arg and Tajan) and a barley cultivar (Nik) were used to assess the change in the chlorophyll content and sodium accumulation over time under saline conditions. Two levels of NaCl (0 and 150 mM NaCl) were imposed as the salinity treatments when the leaf 4 was fully expanded. At 21 days after salt treatment plants were harvested and shoot and root dry weight, root length and sodium root were measured. Sodium accumulation rates and chlorophyll content examined between days 14 and 42 after salt added. Na+ and K+ flag leaf were measured in days 49 after salt treatment started.

Results showed that the rate of sodium accumulation initially was the same for both wheat cultivars in leaf. After 30 days of salinity, the rate of sodium accumulation rose in Arg compared with Tajan. In Nik barley cultivar, shoot sodium concentration was higher than bread whit cultivars. Salinity caused degradation in chlorophyll content in both bread wheat cultivars and at the determination of this experiment Tajan had lower chlorophyll content than Arg cultivar. Nik barley cultivar showed much longer chlorophyll retention than tow bread wheat cultivars. Salinity decrease K+ flag leaf, K+/Na+ flag leaf, shoot and root dry weight, seminal root length, yield and increase Na+ flag leaf and Na+ roots compared to control. Flag leaf K+/Na+ ratio was higher in salt tolerance cultivar (Arg) compared to Tajan and Nik, despite the similar roots sodium concentration. Flag leaf Na+ concentration was the same in tow wheat cultivars and barley under salinity stress and there was no relationship between Na+ exclusion and salt tolerance in cultivars in our experiment. Yield loss of 35 percentages was found in wheat cultivars on average and in barley did not observed remarkable decrease in seed yield. There was may be no beneficial effect of the low Na+ trait at 150 mM NaCl (high salinity level) in all cultivars. Root length reduction in cultivars was due to osmotic stress of salt solution out of the roots. A significant correlation between shoot dry weight and sodium flag leaf showed that sodium concentration in leaf can be used as an index for evaluating salt tolerance.

Given the effect of salinity on shoot growth, it seems that other factors may have influenced net carbon gain before any reduction in the concentration of chlorophyll. It implies that osmotic and tissue tolerance in bread wheat and barley contributed to the salt tolerance in tolerant cultivars and preferential sodium accumulation and maintains in roots and old leave relative to young leaves can caused an increase in salt tolerant. The low shoot sodium concentration was not associated with chlorophyll content in wheat cultivars.

IntroductionProduction of high-yielding and stable cultivars is the most important objective of crop breeding programs, including wheat. The final yield of each plant is determined by the potential of genotype (G), the effect of environment (E) and the interaction effect of genotype × environment (GE). Several methods have been presented to study the genotype × environment interaction and determine stable genotypes, which can totally be divided into two main categories, univariate and multivariate. Univariate methods do not provide a complete view of the complex and multidimensional nature of GE interaction, therefore, the use of multivariate methods is suggested to solve this problem. Among the multivariate methods, AMMI and GGE-Biplot methods are more important. The objective of the current experiment was to investigate the interaction between genotype and environment for grain yield of 20 wheat genotypes and to identify stable and high-yielding genotypes.Materials and methods The plant materials of this experiment were 20 wheat genotypes including 18 irrigated wheat lines along with two control cultivars, Rakhshan and Baharan. The experiment was carried out in a randomized complete block design with three replications in five temperate regions (Karaj, Kermanshah, Zarghan, Boroujerd and Mashhad stations) during two cropping years 2019-2020. Two multivariate methods, AMMI and GGE-Biplot, were used to investigate the interaction effect of genotype × environment and to evaluate the stability of genotypes. R software was used to analyze the experimental data using the AMMI method, and Genstat software was used to analyze the data using the GGE biplot graphic method.Research findingsThe results of combined analysis of variance showed that the interaction effect of genotype × year and genotype × year × location were significant at the 1% probability level. Based on the results of AMMI analysis, the effect of environment, genotype and genotype × environment interaction were significant. Based on AMMI1 and AMMI2 models, AMMI stability value (ASV) parameter and genotype stability index (GSI), genotype 12 with an avearage grain yield of 8.27 tons per hectare was determined as the best genotype. The study of GGE-biplot polygon led to the identification of three mega-environments, that Boroujerd had the highest power of representation and differentiation among different environments. Genotypes 12 and 9, in addition to having high yield, had higher yield stability. Genotypes 12 and 9 were placed in the center of the circle as the ideal genotype and genotypes 5, 7 and 18 were ranked next. Based on the results of both methods, genotype 12 was identified as the most stable genotype.ConclusionThe results of AMMI, AMMI stability index (ASV) and genotype stability index (GSI) compared to GGE biplot results showed that all these indices have a good potential to evaluate the performance stability of genotypes. Nevertheless, GGE biplot results are more effective and practical in examining the compatibility and stability of genotypes' performance in different environments due to the ease of interpreting graphical results.

Salt stress affects 20% of global cultivable land and is increasing continuously owing to the change in climate and anthropogenic activities. Globally, wheat is cultivated on non-saline and saline soils, covering an area of approximately 214.79 million hectares (Becker-Reshef et al., 2020). Salinity stress negatively affects the growth and development of wheat leading to diminished grain yield and quality. For this reason, it is important to develop effective strategies to improve yield through salt tolerance. The breeding of salinity-tolerant cultivars through selection and breeding techniques is one of the effective methods in the production and exploitation of saline soil and water.

In order to study the effects of salinity stress on grain yield, phenological and morphological traits and salinity tolerance indices among bread wheat elite lines, two separate experiments in a randomized complete block design with three replications were conducted in two saline and normal environments during two cropping years of 2019-2021. 20 wheat cultivars and elite lines cultivated at the South Khorasan Agricultural and Natural Resources Research and Education Centre. After determining the grain yield in both conditions, MP, GMP, TOL, HARM, STI and SSI indices were calculated and using SAS software, their correlation with grain yield was investigated and using STATISTICA software, the three-dimensional distribution of each cultivar and line was plotted. Combined analysis of variance was performed to determine the main and interaction effects in the two years of the experiment and the means were compared by Duncan's multiple range test at the level of 5% probability. Bartlett's uniformity test was performed before the combined analysis of variance. Analysis of variance and mean comparison was performed using SAS-9.0 software and cluster analysis was performed by Ward method through StatGraphics program.

The reaction of wheat lines were different in two environments and salinity stress reduced grain yield. The experimental results showed that different wheat lines react differently to salinity stress. Salinity stress decreased grain yield and morphological traits in all lines compared to normal conditions. Salinity stress shortens intermediates and reduces plant height and consequently leaf and shoot dry weight by reducing cell proliferation and reducing dry matter accumulation (Dura et al., 2011).The difference between cultivars and lines in terms of all phenological, morphological and grain yield in two years of the experiment was significant, which indicates the existence of appropriate diversity in the wheat elite lines. The existence of this genetic diversity can be very useful for selecting high-yielding wheat cultivars in salinity conditions. In the first year of implementation, Narin, line No. 3 and Barzegar with an average of 6494, 6227 and 6072 kg/ha, respectively, in normal conditions and Barzegar, line No. 18 and Narin with an average of 6361, 6166 and 5805 kg/ha respectively, had the highest grain yield under salinity stress. In the second year of the experiment, line number 16, 10 and 4 with an average of 5388, 5305 and 5155 kg/ha in normal condition and Narin, Barzegar and line No. 3 with an average of 4930, 4611 and 4180 kg/ha respectively, had the highest grain yield under salinity stress. Naturally, wheat lines grain yield under salinity stress was lower than their yield under normal conditions. Under these conditions, the plant leaf area of is greatly reduced, which reduces the photosynthetic capacity of the plant, and as a result, the amount of dry matter produced and ultimately the grain yield of the plant is reduced (Munns et al., 2002).

For selecting wheat cultivars and lines in the areas that are most exposed to salinity stress, YI, HM, GMP, STI, MP, RSI and YSI indices and in areas not exposed to salinity stress, MP and STI indices are suggested. Barzegar and Narin check cultivars and line number 10 were determined as the most tolerant and lines No. 14, 13 and 20 as the most sensitive lines to salinity stress by different indices. Cluster analysis of lines based on STI index led to the placement of Barzegar and Narin cultivars and lines No. 3, 4 and 18 in the first cluster in which the mentioned lines have fewer days to heading and in contrast more days to maturity, grain filling period, thousand-grain weights and higher grain yield.

Salinity stress is one of the most important abiotic stresses that have harmful effects on plant performance and quality. So that according to the predictions made until 2050, 50% of agricultural lands will lose their ability to be cultivated due to salinity. Due to the complexity of salinity resistance traits, there is little information about the number of genes, their chromosomal location, and the relative contribution of each gene in the incidence and phenotypic distribution. Locating quantitative genes can break down this complex genetic model into individual genetic components, in which case quantitative traits will also be investigated like monogenic traits.

In order to identify QTLs controlling some root and shoot traits under salinity stress in bread wheat, 148 recombinant inbred lines of spring bread wheat obtained from the cross of Yecora Rojo cultivar (early and dwarf as a parent of American origin) and genotype No.49 (late and tall as a parent originating from Sistan and Baluchestan) were studied with the parents. This research was carried out in 2020 in the research greenhouse of Mohaghegh Ardabili University under salinity and non-stress conditions in pitmas and perlite culture medium and factorial based on a completely randomized design with five replications. Traits measured in this experiment included root length, root fresh weight, root dry weight, fresh and dry weight of shoots. In this study, linkage map was used based on 202 markers (177 SSR markers and 51 Retro transposon Markers). The map length was about 691.36 cM with the average distance of 3.42 cM in every marker pair, and 21 chromosomes covered in bread wheat. QTL analysis was done based on composite interval mapping (CIM) method, and additive effects were estimated for the identified QTLs.

The results of QTL analysis showed that in stress-free conditions, one QTL for root dry weight and shoot dry weight, two QTL shoot fresh weight and three QTL for root wet weight and root length were identified. Under salinity stress conditions, one QTL was identified for root dry weight and root length, two QTLs for shoot dry weight and three QTLs for shoot fresh weight. Among the QTLs identified, QRFW6A.n had the highest additive effect under normal conditions and QSFW2A.s under salinity stress conditions. For shoot dry weight and root fresh weight under normal conditions and shoot fresh weight under salinity stress, the positive additive effect of the located QTL s showed the inheritance of the desired allele at this site from Yecora Rojo's parent. The phenotypic variance justified by these QTLs varied from 5.43 to 8.97 under normal conditions and from 5.51 to 7.43 percent under salinity stress.

In this study, the number of QTLs identified for root and shoot-related characteristics was low, which could be due to the high number of low-impact QTLs, interactions, and environmental effects.

Bread wheat is one of the most important nutritional products throughout the world. Wheat, like other crops, faces many environmental constraints during the growing season, such as iron deficiency in the soil. Iron is one of the essential micronutrients in plants that act as a catalytic cofactor in several key processes including photosynthesis and respiration.

to investigate the expression pattern of genes encoding transcription factors WRKY1, bZIP56 and NAM-B1 under soil Fe deficiancy, a factorial experiment was conducted in a completely randomized design (CRD) with three replications. Pishtaz (Fe-efficient) and Falat (Fe–inefficient) bread wheat cultivars were planted under Fe deficiency (less than 1.5) and adequacy (5 mg Fe / kg soil) conditions and the relative expression of genes was measured in roots and leaves of the plants at vegetative (one month after germination) and reproductive (30% of heading) stages using real time PCR technique.

the results revealed the considerable enhanced expression of WRKY1 in the roots of Fe-efficient (Pishtaz) and -inefficient (Falat) cultivars at vegetative stage. The highest increased expression of bZIP56 and NAM-B1 genes was observed in the leaves and roots of Fe-efficient cultivar (Pishtaz) at vegetative and reproductive stage, respectively. The bZIP56 expression was also considerably enhanced in the leaves of Fe-inefficient cultivar in both stages.

Due to the increased relative expression of WRKY1 gene in leaves and roots of both cultivars at vegetative stage, this gene is likely involved in activating and inducing the expression of genes participating in iron uptake and transport in the early stages of plant growth. Also, the increased relative expression of bZIP56 gene in the roots of both cultivars in the reproductive stage indicates that this gene might be participated in activating the transcription of genes involved in iron absorption from the soil at the end of plant growth stages.

Protein patterns of SDS-PAGE have been widely used to determine genetic variation in cereals. This study was carried out at The Payame-Noor University of Asadabad to study genetic diversity and protein pattern in bread wheat cultivars before and after flowering. 13 bread wheat cultivars were applied to prepare protein patterns based on SDS-PAGE electrophoresis. The highest genetic distance before bolting was between Zare and Gascogen (8 units). The lowest genetic distance before flowering was between cultivars with a distance equal to zero. This result indicates high genetic similarity between wheat cultivars. The most similarity between the cultivars is the value of one, such as Pishgam and Sayson (one means one hundred percent similarity) or Pishgam and Bezustaya (with one). The least similarity is 0.2 between Zare and Gascogen. Based on cluster analysis these 13 bread wheat cultivars were divided into three groups. The results after bolting were largely similar to the protein pattern before blooming. The most similarity between the cultivars is the value of one. Pishgam and Sayson was one hundred percent similar, and Pishgam and Bezustaya as well. The lowest similarity was observed between Zare and Gascogen cultivars with zero and 0.25 between Zare and other cultivars. Based on cluster analysis, 13 wheat cultivars were grouped into four clusters. Zare, Gascogen and Omid cultivars were placed in separate clusters and the rest of the cultivars were classified in one group. Increasing one group indicates the effect of some proteins that are effective in the developmental stages before and after wheat flowering.