رضا فتوت

Symbiosis with arbuscular mycorrhizal (AM) fungi often increases the tolerance of host plants against various stresses. Among abiotic stresses, salinity causes considerable loss in crop productivity. Comprehensive study of plant genotypes response to symbiosis with AM fungi and potential role of this relationship in improving the adverse effects of salinity and increasing plant tolerance would be effective in increasing crop yield. The present study aimed to investigate response of commercial barley varieties to mycorrhizal colonization under salinity stress.

In this experiment, six commercial barley varieties including Khatam, Golshan, Afzal, Aras, Makoui and Dasht were evaluated at two salinity levels of NaCl (0 and 150 mM) and two symbiosis levels including inoculated and non-inoculated with Funneliformis mosseae. A factorial design in a randomized complete block design with three replications was conducted under greenhouse conditions in Zanjan University, Zanjan, Iran. Five weeks after cultivation, barley plants were harvested and the traits related to fungal structures including total colonization rate, and the frequency of hyphae, arbuscule and vesicle were measured. Also, some physiological traits including shoot fresh weight, leaf relative water content (RWC), shoot Na+ concentration, shoot K+ concentration, and Na+/K+ ratio were measured.

The results of this experiment showed that there was a significant variation between barley varieties in terms of colonization rate and hyphae, arbuscule and vesicle frequencies of AM fungus. Also, salinity stress reduced the colonization rate, and hyphae and arbuscule frequencies of the fungus, but increased the vesicle frequency, which this reduction was more considerable in salt-tolerant varieties, Khatam and Afzal, especially in Afzal. The increase in vesicle frequency was also significant only in Makoui, Aras and Dasht varieties. The results showed that salinity stress reduced shoot fresh weight and leaf relative water content, and increased Na+ concentration and Na+/K+ ratio in all barley varieties, but these changes in Makoui, Aras and Dasht varieties especially in Aras were more than other varieties. On the other hand, colonized plants exhibit lower shoot fresh weight and leaf RWC compared to non-colonized ones. However, symbiosis enhanced leaf RWC in Khatam and Golshan varieties under non-stress conditions.

The results of this study showed that there was a significant difference between barley commercial varieties in terms of response to symbiosis with mycorrhizal fungus and response to salinity stress. Although the reduction of colonization rate may help barley plants to prevent the consumption of carbohydrate resources, the expected results of symbiosis in terms of improving barley plant growth or reducing the adverse effects of salinity stress on the plant was not observed in the present study. This indicates the complexity of the symbiotic relationship between plant and fungus, and environmental conditions especially stress conditions can increase this complexity.

The yield of wheat (Triticum aestivum L.), is greatly reduced under environmental stress and decreased temperatures. Therefore, adaptation mechanisms and cold resistance are crucial in this plant. Vernalization is known as one of the essential mechanisms for grain adaptation to environmental conditions, whereby the plant can accelerate the flowering process or flower after a long cold period. Vernalization also plays a significant role in the acquisition of cold resistance in wheat plants. When exposed to low temperatures, certain genes related to vernalization are activated, leading to changes in the plant's physiology and allowing it to a better cold stress tolerance. This process involves complex regulatory mechanisms depending on the cultivar and environmental conditions. Understanding the molecular basis of vernalization and the genes involved in cold resistance could assist in developing new strategies to improve wheat productivity in adverse environments.

In this research, we investigated the expression of three genes, NAC, ERF, and TCP, related to vernalization in two wheat cultivars named Baz and NorthStar, which known as spring and winter cultivars, respectively. The plant samples were preserved in growth racks and applied for vernalization treatment after the tillering stage. RNA extraction was performed at this stage. Real-Time PCR technique was then utilized to analyze the gene expression. To better understanding the function of these genes in response to cold stress, the promoter of the three studied genes was analyzed by screening 500 nucleotides upstream of the wheat TSS. The vernalization treatment was applied at two levels of 14 and 21 days and compared to the control plants under 4°C.

The results showed that the expression of all three genes (TCP, NAC, and ERF) decreased under the vernalization treatment. However, the expression of the TCP and NAC genes increased after 14 and 21 days of treatment in the NorthStar and Baz varieties, respectively. In general, the decreased level of expression was shown by increasing in the number of vernalization days. Notably, the expression of the ERF gene reduced in both tested varieties with the increased number of vernalization days. This trend was also observed in the expression of the NAC gene. However, the vice versa was observed for NAC gene in the Baz variety by an increased expression. In the Baz variety, the expression rate of the TCP gene decreased with an increase in the number of vernalization days, whereas in the NorthStar variety, the gene expression increased and then decreased after 14 and 21 days of treatment. Based on the abundance and diversity of the identified elements resulting from the analysis of the promoters of the studied genes, 28 types of regulatory elements were identified, many of which are binding sites for transcription factors responding to biotic and abiotic stresses Top of Form.

Despite the similarity of the pattern of expression changes of all three genes in the two investigated cultivars, the intensity of the changes in the two cultivars was not same, which could be due to different reactions to cold stress. The results show the complexity of gene expression regulation in wheat vernalization. Additionally, the multiplicity of stress-responsive transcription factor binding sites in the promoter region of these genes could be a justification for the complexity of regulating their expression during vernalization and response to cold stress.

Copper, as a micronutrient, is essential for the synthesis of enzymes and proteins. However, excessive copper concentrations can be highly toxic and inhibit the photosynthetic and metabolic pathways in plants, ultimately leading to reduced biomass, delayed flowering and fruiting. Sodium nitroprusside (SNP) (as a nitric oxide donor compound) plays a significant role in plant growth and development, from germination to organ senescence, signal transduction, regulation of antioxidant defense systems, and reduction of heavy metal toxicity. In the present study, the combined effects of two levels of copper sulfate (600 and 1200 µM) and sodium nitroprusside (150 µM) were investigated on some physiological and morphological activities of okra (Abelmoschus esculentus L. cv. Clemsonspineless) is grown hydroponically. The experiments were conducted in a complete randomized design with three replications. Based on our results, the high copper concentration resulted in a reduction in chlorophyll content, essential nutrients, growth parameters and an increase in malondialdehyde, hydrogen peroxide, electrolyte leakage, total protein, proline, soluble sugars, peroxidase enzyme activity and copper content in both the roots and leaves of okra compared to the control plants. Conversely, SNP foliar spray led to an increase in total chlorophyll, uptake of essential elements, peroxidase enzyme activity and a decrease in copper concentration, malondialdehyde and hydrogen peroxide content, as well as ion leakage in okra plants. Therefore, it seems that the application of SNP was able to mitigate the negative effects of copper sulfate stress significantly and enhance the tolerance of okra plants to copper stress conditions.

The first step in breeding programs is accurate identification and sufficient knowledge of genetic parameters, including the type of gene action and the heritability of the studied trait. Development of high yielding lines and the identification of heterotic groups are the most important objectives of corn breeders. Also, determining the inbred lines of parents that create suitable hybrids is very valuable and can reduce the duration of the hybrid production program in corn. Graphic diallele analysis is one of the biometric methods of genetic analysis of quantitative and multigenic traits, the results of which can be very useful for improving traits within and between populations as well as producing hybrid varieties. The objective of this experiment was to investigate the genetic control of grain yield and related traits in maize inbred lines. The results of this study can be useful in selecting the most appropriate breeding method for the studied traits and producing high yielding maize hybrids in Zanjan region, Iran.

To estimate the type of gene action, the number of genes, heritability and other genetic parameters controlling grain yield and its related traits in maize inbred lines, a 5×5 diallel crosses design was used. The parents and 20 hybrids derived from their crosses were evaluated in a randomized complete block design with three replications in the research field of Zanjan University, Zanjan province, Iran, in 2019. The studied traits were including plant height, ear length, number of grain rows in ear, number of grains per row, 300-grain weight, and grain yield. The genetic analysis of the data was done according to Hayman (1954) graphical approach.

Estimating the genetic parameters showed both additive and non-additive gene effects in controlling the studied traits in this research. The results of graphical analysis also indicated the existence of over-dominance gene effects in controlling grain yield and its related traits. The alleles increasing the studied traits were of dominant type. Broad-sense heritability varied from 54% for 300-grain weight to 89% for ear length, and narrow-sense heritability ranged from 29% for 300-grain weight to 41% for number of grain rows per ear. Although high general heritability was estimated for most of the studied traits, which indicates the greater role of genetic factors and the relatively less influence of environmental factors in controlling the diversity of these traits, the existence of over-dominance effect of genes and low narrow-sense heritability indicates that the selection of these traits in the early generations will not be successful. Therefore, the breeding methods based on hybridization and selection in advanced generations can be useful in improving and breeding the grain yield and its related traits in the studied maize inbred lines. Also, the use of EP80 inbred line which had the most number of dominant genes for controlling yield and its components may have promising results in improving these traits in breeding programs.

In total, the results of the current study regarding the type of gene action controlling grain yield and its components in the studied maize inbred lines showed the important role of the over-dominance effects of genes. Therefore, the most appropriate strategy for exploiting these genes and improving the population is to obtain hybrid varieties that provide the possibility of exploiting heterosis in the investigated parents. is to use the heterosis phenomenon and produce hybrid varieties.

Investigating the effect of various sources of sulfurous compounds along with the inoculation of Thiobacillus bacteria on corn plants under stress conditions of lead and zinc metals, Factorial experiment of randomized complete blocks design was carried out in the Agricultural Research Greenhouse of Zanjan University in 2021. The treatments include elemental sulfur (0.75, 1.25 and 2 g/kg soil), sulfur with thiobacillus bacteria(biosulfur) (1, 2 and 3 g/kg soil) and potassium sulfate (0.5, 1 and 1.5 g/kg soil). The results showed traits were significant in the vegetative growth stage in all applied treatments. The treatments increased the amount of chlorophyll, enzymes compared to the control. Then decreased the leaf temperature, Increasing the length of leaf cells. also, it increases the leaf area and leaf production rate in plants. This increase was higher in sulfur treatment with bacteria. But the treatments of 2 grams of elemental sulfur and 1.5 grams of potassium sulfate caused stress in the plant and reduced the amount of traits compared to the control. Also, the plants in contaminated soil were stressed and the amount of the mentioned traits also decreased. However, with the application of treatments, the amount of carotenoid, total protein and peroxidase traits increased, which reduced the stress in plants and increased the amount of traits and growth indicators compared to control in contaminated soil. Sulfur treatment with bacteria, compared to other applied treatments, by activating the enzymatic and non-enzymatic defense system of the plant, causes the plant to tolerate stress and improve plant growth.

Investigations showed that the pollution of heavy metals, especially lead, in fields has caused tension and decreased yield. This issue has caused concern about the risk of consuming contaminated food for human health. The role of plant regulators in heavy metal stress conditions has been of interest in recent years. Lead and zinc (in high concentration) are toxic metals for plants, which are easily absorbed by the plant's root system. As a result, they cause damage to plant growth and development and prevent enzyme activity. Maize is economically important for harvesting seeds and fodder. However, in areas contaminated with metal stress, due to the absorption of metals by the plant, the yield of the cultivated plant in these areas decreases, for this purpose, an experiment aimed at the effect of concentration and different methods of salicylic acid hormone on growth, photosynthesis and anatomical characteristics. and physiological in corn under the stress of zinc and lead metals and also the possibility of reducing the risk of toxicity of these elements is investigated.

In order to investigate the mitigating effects of two methods of applying salicylic acid hormone on corn plants under heavy metal stress, the experiment was carried out as follows. The concentration of metals included: different concentrations of lead (0 and 250 mM) and zinc (0 and 2500 mM) and the treatments were with two methods of foliar spraying and priming in zero concentrations (distilled water), 750 and 1500 μmol salicylic acid and a group of seeds without stress and no treatment were considered as controls. By implementing a factorial design on morphological traits (height, plant temperature, temperature difference between the environment and leaves, and leafing ratio) and physiological traits (membrane stability index, chlorophyll fluorescence, proline, soluble sugars, carotenoid, protein and some enzymes) as well as the absorption of lead and zinc metals in the root tissue and the aerial part of the plant under hydroponic cultivation conditions. The obtained results were subjected to statistical analysis using SPSS statistical software. The mean comparison of experimental data was also done with Duncan's test. Excel 2003 software was used to draw the figures.

Morphological traits such as: plant temperature, difference between Environment and leaf temperature and physiological traits such as: proline, soluble sugars, carotenoid, protein and some enzymes increased and some other traits such as: height, and leafing ratio, index Membrane stability, chlorophyll fluorescence decreased compared to the control. These traits showed better results in seed priming treatment without stress. However, the use of foliar spray under lead-zinc and lead stress improved the stress effects by reducing the absorption of heavy elements by the root system.

SA activates the defense system of plants by synthesizing a number of proteins and increasing proline osmolytes and soluble sugars and enzymatic and non-enzymatic antioxidants such as carotenoids. As a result of reducing the oxidative stress and protecting the chloroplast membrane and the photosynthetic apparatus, the photosynthetic production is improved, resultly, the height and the proportion of the leaves increased. SA also prevents the absorption of heavy metals by the root system of the plant and its transfer to the aerial part of the plant, which reduces the signs of stress in the aerial part of the plant. By applying salicylic acid, some properties were improved by reducing the effects of stress. The use of foliar spraying improved the physiological and morphological traits during plant growth and worked better than the seed priming method. resultly, in farms with two metals lead and zinc, it is possible to tolerate the stress of these two metals by foliar spraying treatment.

In recent years, the use of allelopathy in weed management has received great attention. In this study, the effect of allelopathy of a double haploid population of barley on the growth characteristics of wild rye and hedge mustard was studied in the Laboratory of Agriculture and Plant Breeding, Faculty of Agriculture, Zanjan University. Some germination traits (root and shoot length, fresh and dry weight of seedlings) and their heritability were measured in barley, rye and hedge mustard. The results showed that the double haploid lines, rye and hedge mustard are significantly different in terms of all four traits of fresh weight, dry weight, root length and stem length. Lines 25 and 34 showed the lowest allelopathy and lines 17 showed the highest allelopathy on rye. Lines 39, 48, 55, 65, 66, 68, 70, 75, 76, 77 and 82 of barley were also affected by rye allelopathy. Lines 73 and 17 had the highest rate of allelopathy on hedge mustard plant, as well. Except for the dry weight of barley control, the length of roots and stems of hedge mustard, which had low private heritability, showed moderate other heritability traits.

Industrialization and destructive human activities have led to a rapid spread of heavy elements contamination in soil. The purpose of this study was to investigate the effect of silicon and salicylic acid on yield and physiological traits of corn in Rahimi and Molavi farms (contaminated with heavy metals and located near lead and zinc factors in Zanjan) in 2020, by using a factorial design based on randomized complete blocks. Factors included spraying salicylic acid at zero, 600, 1200, and 1800 µM, and spraying nanosilicon at zero, 600, 1200 and 1800 mM. Based on the results of soil analysis, lead, zinc, and cadmium concentrations in both fields were higher than the allowable limit and this heavy metal contamination was more severe in Rahimi field. Heavy metal contamination reduced plant height, grain yield and yield components, biological yield, chlorophyll content, and proline levels. The highest grain yield and grain weight were obtained with 1800 µM salicylic acid and 1200 mM nanosilicon treatments, and the lowest with the control treatment (without salicylic acid or nanosilicon). The highest chlorophyll content was obtained from 1800 µM salicylic acid treatment on Molavi's farm and the maximum amount of chlorophyll was observed in 1800 mM nanosilicon treatment. Overall, the treatments improved the yield, chlorophyll content, and relative water content of corn leaves. It is recommended to spray 1800 µM salicylic acid and 1200 mM nanosilicon on the corn fields in this area to increase the stress tolerance under heavy metal conditions.

Understanding allelopathy in crop plants is necessary and essential in order to improve and increase yield, maintain species diversity, manage plants and protect the environment. Despite the studies conducted on plant allelopathy, the development and introduction of cultivars with high allelopathic ability is limited to a large extent due to the lack of information about its genetics.

To investigate the allelopathic effect of double haploid lines of barley and rye, an experiment was conducted in the form of a simple lattice design with two replications in the research farm of Zanjan University in 2017. A row of rye was planted in the middle of the barley experimental plots. Some physiological traits and plant height were measured in rye and phenol content was also studied in the atmosphere under natural conditions.

The results of the effect of double barley allelopathy lines showed that there was a significant difference in plant height, chlorophyll b content, carotenoid content, carbohydrate content and chlorophyll content index (SPAD) in rye plant. Barley double haploid lines also had significant differences in terms of phenol content.

The results of this research can indicate the potential of double haploid population of barley known as OWB in allelopathy genetic studies.

To investigate the combining ability of sunflower (Helianthus annuus L.) inbred lines and also the inheritance of several physiological traits of this plant in normal irrigation and water-deficit-stress conditions, eight inbred lines with different drought tolerance were crossed with three cytoplasmic male sterile lines. The resulting 24 hybrids, 11 parents, and a commercial hybrid (Barzghar) as the control were evaluated in a split-plot design based on the randomized complete block design with three replications. Irrigation was applied in the main plots at two levels, normal (irrigation based on 100% water requirement) and stress (irrigation withhold after the appearance of the inflorescence), and 36 sunflower genotypes in subplots. During the growing season, chlorophyll content (Chl), relative water content (RWC), leaf water loss (LWL), early growth rate (EGR), leaf temperature (LT), and grain yield (GY) were measured. The analysis of variance showed the significant effect of water-deficit stress on Chl, RWC, LT, and GY. According to the results of the line × tester analysis, the effect of lines was significant for Chl, LWL, EGR, and GY in normal conditions, and on Chl and EGR in the water-deficit-stress conditions. In the case of the testers, there was a significant difference in Chl, EGR, and GY under normal conditions, and in LWL, EGR, and GY under stress conditions. The significant effect of lines and testers on these traits indicated a difference between their general combining ability (GCA) and the existence of additive gene effects. The interaction of line × tester was significant only for GY in normal conditions. Chl and EGR had a relatively high broad-sense and narrow-sense heritability at both conditions. The GY had also relatively high broad-sense heritability in both conditions but its narrow-sense heritability was only relatively high at the water-deficit-stress conditions. The C122 and C123 lines and the A19 tester had the highest positive GCA for GY in both conditions. The hybrid A196 × C41 in the normal conditions and A112 × C111 in the stress conditions had a positive SCA. Among the physiological traits, only LWL showed a significant correlation with GY in normal conditions. Under water-deficit-stress conditions, LWL and EGR had a positive correlation with GY, while LT showed a negative correlation with GY. In conclusion, it seems that LWL, EGR, and LT can be used to indirectly improve GY of sunflower under water-deficit stress conditions.

Wheat (Triticum aestivum L.) is one of the most important crops and is grown nearly everywhere in the world. Wheat is the primary staple food in many countries. In light of the fact that wheat yield varies depending on environmental conditions, it is crucial to employ strategies that increase wheat yield. To investigate the effects of foliar application of cytokinin on the physiological traits and yield of wheat cultivars, a factorial experiment based on randomized complete block design with tree replications was conducted at the research farm of the Agriculture Faculty, University of Zanjan, during the 2016 cropping seasons. Six wheat cultivars (Azadi, Karaj 3, Roshan, Falat, Sardari and Yavarus) were treated with foliar applications of cytokinin (6-benzylaminopurine) at two levels (0 (control) and 50 µM). At the 50% stage of cluster emergence (code 55 Zadox growth stage), hormone foliar application was performed three times per week. Foliar spraying was done at sunset. To improve absorption, five ml of diluted Tween 20 (0.1%) was added to each 20-liter sprayer. 10 days after the third spraying, a sample was taken and the traits were measured in order to determine their value. The application of cytokinin significantly increased photosynthetic rate, leaf area index durability, weight per thousand grains, biological yield, and grain yield. The application of cytokinin had no significant impact on the greenness index of the Falat, Karaj 3, Roshan, and Yavarus cultivars, but increased the greenness index of the Sardari cultivar by 116.2% and decreased the greenness index of the Falat cultivar by 12.0%. The Karaj 3 cultivar had the highest photosynthesis with an average of 10.6 μmol.m-2.s-1 net CO2 assimilation rate, while the Falat cultivar had the lowest photosynthesis with 6.46 μmol.m-2.s-1 net CO2 assimilation rate. The application of cytokinin increased the leaf area index duration of the Falat, Karaj 3, and Yavarus cultivars while having no effect on the other cultivars. The foliar application of cytokinin had no effect on the number of seeds per plant, but there were significant differences in the number of seeds among the cultivars studied. The cultivars Karaj 3 and Yavarus had the highest and lowest seed yields per plant, with 172.6 and 83.7 seeds per plant, respectively. The foliar application of cytokinin increased the final grain dry weight of the Azadi, Roshan, and Yavarus cultivars by 5.6%, 14.8%, and 6.2%, respectively, but had no effect on the Karaj 3, Falat, and Sardari cultivars. The Azadi cultivar with an average of 1.08 mg/day and the Sardari cultivar with an average of 1.55 mg/day had the lowest and highest grain filling rates, respectively, among the cultivars studied. Except for the cultivar Roshan, the application of cytokinin increased during the grain filling period of all other cultivars. Compared to the control treatment, cytokinin increased the one-thousand seed weight by 5%. Cytokinin increased the weight of one-tousand seeds by 5% compared to the control treatment. The application of cytokinin increased the yield of the Yavarus, Karaj 3, and Sardari cultivars by 23.7%, 30.1%, and 65.5%, respectively, but had no effect on the yield of other cultivars. In the absence of cytokinin application, Azadi had the highest grain yield at 5700 kg/ha, while Roshan had the lowest at 3100 kg/ha. The application of cytokinin had no significant effect on the harvest index. The Sardari and Yavarus cultivars had the highest and lowest harvest indices (31.4% and 25.1%, respectively), whereas the harvest indices of the other cultivars did not differ significantly. Morphological, physiological, and yield-related traits differ among wheat cultivars, as demonstrated by the results of the present study. The results demonstrated that the response of wheat cultivars to cytokinin application was highly variable, and that hormone application may be ineffective or have a negative impact on certain traits.

To investigate the effect of foliar application of cytokinin on gas exchange, remobilization and allocation of photosynthetic materials of wheat cultivars, an experiment was carried out under field conditions. The experimental treatments included foliar application of 6-benzylaminopurine at two levels (0 as control and 50 μM), and six wheat cultivars (Azadi, Karaj 3, Roshan, Falat, Sardari and Yavarus) which as factorial experiment in a randomized complete block design with four replication were studied. The results showed that foliar application of cytokinin increased leaf area index (LAI) and Roshan had the highest leaf area index. Photosynthetic rate of the studied cultivars was also different and the use of cytokinin increased the photosynthetic rate. Foliar application of cytokinin increased the remobilization of Falat, Roshan and Sardari cultivars and decreased Azadi cultivar, but had no significant effect on Karaj 3 and Yavarus cultivars. The effect of cytokinin on the allocation of photosynthetic assimilates to stem, leaf and spike of the studied cultivars was very different, so that with the application of cytokinin, the allocation of photo-assimilates to leaf decreased in Falat and increased in the other cultivars, but in the case of spike, the allocation of photo-assimilates to spike decreased in Roshan cultivar and increased in Karaj 3 and Sardari cultivars, while it did not affect on the other cultivars. In contrast, the allocation of photo-assimilates to stem was reduced about 3.3% by foliar application of cytokinin and Sardari, Yavarus and Roshan cultivars had the highest percentage of the allocation of photo-assimilates to stem. Grain yield of Karaj 3, Yavarus and Sardari cultivars increased by foliar application of cytokinin and the highest and lowest grain yield was observed in the control treatment (no application of cytokinin) in Azadi (5700 kg/ha) and Roshan (3100 kg/ha) cultivars, respectively, while under cytokinin foliar application, Yavaros and Roshan cultivars with 6300 and 3300 kg/ha had the highest and lowest grain yield, respectively. The results of this experiment showed different effects of cytokinin on different traits and wheat cultivars, but to obtain more accurate and complete results, it is suggested to measure the internal cytokinin concentration of wheat cultivars.

To study the effect of drought stress on genetic parameters of yield and some morphophysiological traits of sunflower, the hybrids obtained from the cross of eight restorer lines with three sterile male lines and two normal irrigation and drought stress conditions were evaluated in a split-plot experiment based on randomized complete block design with three replications. The results of line × tester analysis showed that under normal conditions, line and tester effects were significant for all studied traits. Under stress conditions, the effect of lines was significant in chlorophyll index, initial growth rate, and plant height and the effects of tester were significant in early growth rate, plant height, stem diameter, and grain yield. Estimation of the effects of general combining ability of traits showed that two lines, C122, C123, and A19 tester had the highest positive combining ability in grain yield and could be used as good parents for producing suitable hybrids in breeding programs. Estimation of heterosis of the studied traits showed that the highest rate of heterosis of grain yield under normal and stress conditions were 126.6% and 123.9%, respectively, for the A112×C41 hybrid. Two traits stem diameter, and head diameter showed a significant correlation with grain yield under normal conditions, while four traits, initial growth rate, plant height, stem diameter, and head diameter, was correlated positively with grain yield under stress conditions.

In the 21st century, climate changes and global warming have become critical concerns, in that they can affect many of the natural phenomena. It is reported that aeroallergen sensitization is influenced by changes in climate. Bet v 1 is an important birch pollen respiratory allergen and a prototype for the PR-10 protein family, which has been reported in wheat pollen. Two wheat genotypes were exposed to water deficit at the meiosis stage of anthers to investigate the effect of drought stress changes on wheat pollen Bet v 1 expression. Then, mature anthers of wheat underwent molecular experiments in the anthesis stage. Expression analysis was carried out, using Real-time PCR, on the Bet v 1 gene that encodes allergens. The results indicated the induction of Bet v 1 in both genotypes in the water deficit condition. The genotype which had been improved by breeders for tolerating drought more than the other genotype revealed more increase in Bet v 1 expression. Given the great spread of wheat, especially improved genotypes worldwide as a pivotal and crop plant and regarding wheat pollen effect on provoking allergy in humans, Bet v 1 can cause new distress in human society. Therefore, this finding is considered as a new verification of concerns of climate change on human health, which emphasizes the importance of efforts to alleviate climate changes to avoid the risk of public health.

Based on recent statistical survey, the cancer is the third important factor in Iran mortality. Vinblastine and vincristine alkaloids are dominantly biosynthesized in the aerial parts of periwinkle, broadly applied for cancer treatment. Therefore, over production of these alkaloids by using the biotechnological approaches is inevitable. Since the terpenoid indole alkaloids (TIAS) biosynthesis pathway is adjustable, modification of underlying substrate and enzymes concentration by biotic and abiotic elicitors are important approaches for overproduction of these metabolites. Abiotic and biotic are induced the immune systems of periwinkle and subsequently increased the biosynthesis and accumulation of vinblastine and vincristine. So this study we reviewed and discussed the impacts of different abiotic and biotic elicitors on terpenoid indole alkaloids (TIAS) biosynthesis and consequent secondary metabolites over production. Based on our knowledge this is the first study on the reviewing of the different elicitors on vinblastine and vincristine and it will be more helpful in the future studies.

The response of a plant to drought stress is positively related to physiological traits and gene expression. Various recent studies suggest that membrane channel proteins, named aquaporin (AQPs), by affecting stomatal conductance behavior could be involved in plant responses to stress conditions. The sunTIP7 gene is a member of AQPs protein that is included in different environmental stress such as drought stress. In this study in order to investigate the sunTIP7 gene expression and its relation with relative water content (RWC), stomatal conductance, shoot fresh and dry weight, root area, chlorophyll index (SPAD) and electrolyte leakage (EL), six selected sunflower (Helianthus annuus L.) inbred lines were planted in a greenhouse under normal irrigation and water deficit conditions. The water deficit treatments were applied during 4th leaflet to flowering stage. Drought conditions reduced crop growth and physiological traits. The highest stomatal conductance was found in the C138 line under both conditions. Sunflower lines had different fold change expression of sunTIP7 gene under drought stress. The expression of the sunTIP7 genewas the lowest in C138, and this downregulation may explain its highest stomatal conductance. However, there was not any clear relationship between physiological traits and expression of sunTIP7 gene in all six sunflower inbred lines. These results suggest that drought tolerance in sunflower is a complex trait and there is no simple molecular explanation for drought tolerance in sunflower lines.

Breast cancer is the most common malignancy in women throughout the world. Among the various methods for preventing and treating cancer, plant natural compounds have more benefits than chemical drugs and have less side effects. Recently, many studies have been carried out on the antioxidant, anticancer, antiproliferation, and antiinflammatory properties of plant lignans, indicating the importance of these compounds in the prevention and treatment of various diseases. In the present study, the cytotoxic effects and inducing apoptosis of pinoresinol and lariciresinol lignans were investigated on SKBr3 breast cancer cell line.

SKBr3 cells were treated with different concentrations of both pinoresinol and lariciresinol, separately for 72 hours. Then, cell viability and cells morphological changes were determined using MTT assay and inverted light microscope, respectively. Also, apoptosis induction was analyzed by flow cytometry using an Annexin V-FITC apoptosis detection kit.

Both pinoresinol and lariciresinol treatments induced morphological changes, decreased cell growth, survival, proliferation and a significant increase in apoptosis induction in SKBr3 cell line compared to control cells in a concentration-dependent manner.

Inducing apoptosis and preventing the growth and proliferation of cancer cells are important mechanisms in the treatment of cancer. Pinoresinol and lariciresinol can be used to reduce cell proliferation and increase apoptosis induction in prevention and treatment of breast cancer.

Floral transition through vernalization has a large influence on cold tolerance and agronomic traits in winter cereals. It is now apparent that in many plants small RNAs play critical roles in determination of the flowering time. There is evidence suggesting that the miR156 and miR172 families play a key role in the flowering transition of plants. In this study, the expression of two temporally regulated miRNA (miR156 and miR172) and their targeted genes (SPL3, AP2) were investigated in the winter bread wheat cv. Norstar and the spring bread wheat cv. Baj in 2017-2018 cropping season. The vernalization was exposed to the cold treatments (4°C) for 2 and 14 days at seedling stage. Time to flowering was estimated using the final leaf number (FLN), which significantly decreased under vernalization treatments, only in winter cultivar 'Norstar'. Moreover, analysis of variance showed that vernalization treatments × cultivarsv interaction effect was significant on FLN. Comparison of gene expression using bootstrapping method showed that the expression of miR172 was significantly down-regulated only in Norstar under vernalization treatments. Similarly, the expression of miR156 was completely different under vernalization treatment in two cultivars. Increased expression of miR156 in Baj cultivar was not significant, but vernalization treatment significantly decreased the expression of this gene in cv. Norstar. Although the induction of AP2 expression during vernalization (14 days) was observed in both cultivars, but, the expression levels of SPL3 were only significantly decreased in cv. Norstar, and this reduction was more in two-day vernalization. Unexpectedly, in this experiment, there was no relationship between up-regulation of both miRNA and down-regulation of their targeted genes in two bread wheat cultivars. These results demonstrated that molecular mechanism of flowering time in bread wheat is complex and still largely unknown.

Catharanthus roseus is an important multipurpose medicinal plant. In this study, in vitro proliferation and root induction of periwinkle were optimized and regenerated plants were subsequently surveyed for genetic homogeneity using the inter simple sequence repeat (ISSR) markers. Shoot tips and nodal segments were cultured in Murashige and Skoog (MS) medium supplemented with different concentrations of benzylamino-purine (BAP), gibberellic acid (GA3), and indol-3-butyric acid (IBA) hormones. ISSR profiling of regenerated plants as well as the mother plant were surveyed with five primers. The highest establishment rate (80.67%) was obtained in the MS medium containing 1.0 mg L-1 GA3 and 1.0 mg L-1 BAP. Highest proliferation rate (5.20 shoots/explant) and average shoot length (6.30 cm) were observed in 1.5 mg L-1 BAP + 0.5 mg L-1 IBA. Moreover, the best rooting response (85.30%) was observed on half strength MS containing 1.0 mg L-1 IBA. Genetic fidelity analysis using ISSR markers showed the monomorphic banding pattern of the micro-propagated plants and the mother plant, which highlighted their genetic uniformity. This implies that periwinkle micropropagation through shoot tip is the most reliable method for true-to-type production of C. roseus in a large scale.

Corn susceptibility to cold stress during early autotrophic growth is an important limitation for its cultivation in the cold areas. To identify the physiological basis of cold tolerance heterosis in maize seedlings, the changes of some physiological traits were studied in maize cold tolerant and susceptible inbred lines and hybrids at seedling stage in University of Zanjan, Iran, in 2017. The results showed that the effect of cold treatment onchlorophyll fluorescence, relative water content, electrolyte leakage,chlorophyll acontent, chlorophyll bcontent, carotenoids, root volume, root area androot dry weight were significant. The better-parent heterosis was detected in chlorophyll b content, root area, root volume and electrolyte leakage in most hybrids. Performance of MO17×EP80 hybrid was better than other hybrids for all physiological traits under stress conditions. EP42×MO17 and A661×MO17 hybrids also had better root growth and extension under cold stress conditions.The significant correlation was only observed between heterosis values of some traits that had a common genetic, physiological and developmental basis, such as root dry weight and relative water content or chlorophyll b content and electrolyte leakage. However, the correlation between heterosis values of the other traits was generally poor, indicatingthat the genetic basis of heterosis is trait dependent and probably not controlled by a single mechanism. The significant differences among genotypes in all traits, provide a new opportunitto improve cold stress tolerance in a tropical plant using plant breeding.

Wheat is a pivotal crop plant in Iran. However, it is mostly grown in drought prone areas of Iran. On the other hand, the trend of global warming is increasing. Therefore, in order to better use the limited water sources, it is needed to improve wheat yield by studying the mechanisms of enhancing water use efficiency (WUE). This study was conducted to determine the effect of stomatal conductance (gs) on water use efficiency and its components in wheat (Triticum aestivum L.). Seven bread wheat cultivars (Marvdasht, B.C.Roshan,Darab2, Vee/Nac, Shiraz, Chamran, Maroon) were grown in pots under well-watered conditions. The pattern of variation for WUE and its components was different for cultivars. Stomatal conductance showed a positive correlation with total water use, transpiration efficiency and grain yield. A path analysis revealed that transpiration efficiency had a higher direct effect on grain yield (0.91) than did harvest index (0.40). Although gs showed a direct effect of almost zero on grain yield, but imposed its effect indirectly via transpiration efficiency (0.47).

Plants are using various mechanisms at the molecular, biochemical and physiological levels for resistance to cold stress. These responses are controlled via stress phytohormones. One of the main hormones is jasmonic acid that plays main roles in various stress, however, there are few studies of the effects of the hormones on cold stress. Its signaling pathway in response to low temperature has remained unknown. In this study, a weighted gene co-expression network was utilized to determine the effect of jasmonic acid in response to cold by using microarray data at Arabidopsis. The 15 gene groups were found that each one controls a special process. Photosynthesis and carbohydrate catabolic and metabolic processes are the most important biological processes in response to the two stimuli. Gene co-expression network displays that transcription factors play main roles in the processes. According to results, two transcription factors ERF13 and ORA47 candidate for relationship between jasmonic acid and cold tolerance and possibly intermediate between CBF1 and CBF2 transcription factors and regulatory proteins in the jasmonic acid signal transduction pathway, tify family. Three transcription factors (HY5, bHLH15 and PIF3) also cooperate in the signaling pathway to respond to low temperature in plants.

Induced resistance (IR), activated either by a prior pathogen infection (biological induced resistance) or by treatment with a chemical. Induced resistance is thought to play an important role in the preservation of plants in nature. Although several types of IR have been identified, the one that has been studied most extensively is systemic acquired resistance (SAR). Systemic acquired resistance is an inducible defense mechanism that plays an important role in disease resistance in plants. It has been found that agrochemical components cause SAR in plants. One of the effective agrochemicals is benzothiadiazole (BTH). The exogenous application of BTH to leaves augments the sensitivity of cells to respond to elicitation. BTH has been developed as a novel disease control compound that is translocated throughout the plant where it acts by inducing an inherent disease resistance response. In order to investigate the mechanisms of BTH biochemical activity and its induced genes, BTH-related EST sequences were mined from NCBI site. Clustering and assembling about 370 rice EST sequences were formed after treatment with BTH resulted in 33 contig and 234 singltone, and then functional groups were determined and compared with the two libraries of common genes. The results of this study indicated that after application of BTH on rice, kinase, LHCB and OEEP proteins as well as the carbonic anhydrase and Ribulose enzymes are expressed. This study is the first report that effect of BTH on plant photosynthesisc. In this study novel candidate genes were identified which may have a possible involvement in plant defense mechanism. This kind of bioinformatics studies may be useful in molecular breeding programs in rice for development of diseases tolerance varieties.

A large amount of the world lands under the cultivation of wheat is under drought stress. In cereals, the reproductive stage is the most sensitive phase to drought stress. Despite the importance of drought stress in reproductive stage and its role in wheat yield reduction, the mechanisms involved in it have been less studied. In the present study, the expression of miR166 and miR167 in mature anthers of two tolerant (Dezfoul or D-10) and susceptible (Shiraz) wheat genotypes under drought conditions in reproductive stage was investigated. Stress tolerance index (STI) for grain number per spike, grain set and pollen viability was higher in tolerant genotype, Dezfoul, compared to susceptible genotype, Shiraz. Drought stress induced expression level of both miRNAs in both genotypes. The amount of miR166 increase in the susceptible genotype, Shiraz (over 14 times compared to the non-stress conditions) was about twice more than the tolerant genotype,Dezfoul (about 8 timesmore than the non-stress conditions). Under drought stress conditions, expression of miR167 in Dezfoulgenotype was more than two fold and in Shiraz genotype more than four timeshigher thanthe non-stress conditions. Both miR166 and miR167 regulate development of floral organs such as microspore development. In conclusion, the effect of drought stress on their expression changes can affect male sterility in wheat, and modifying the expression of these two miRNAscan lead to efficiency of pollen development and successful anther dehiscence which is rooted in signal transduction.