فهرست مطالب mohammad mohsenzadeh golfazani

This study was conducted for investigating the effect of drought different levels on morphological and physiological traits of Canola and investigating relative expression of antioxidant genes to identify the antioxidant response of tolerant genotype at drought different levels. The factorial experiment based on unbalanced completely random design was conducted at the end of the 5-leaf stage of Canola in 3 replications in the greenhouse of Agricultural Sciences Faculty of Gilan University on the year 2022. The effect of different drought levels, including non-stress (100%), low (75%), medium (50%), severe (25%) and very severe stress (20%FC) on morphological and physiological traits in SLM046 and Licord Canola genotypes, as well as the relative expression of important antioxidant genes of Ferredoxin-NADP+oxidoreductase (FNR) and NADPH-thioredoxin reductase (NTR) in the tolerant genotype were investigated using Real-time PCR based on Livak method. The interaction effect of stress on genotype for root length, shoot and root dry weight, allometric coefficient, root water weight, chlorophyll a and b, total chlorophyll, carotenoid and anthocyanin was significant at 1% probability level. The allometric coefficient at 20%FC, and root dry weight at all levels were higher in SLM046 than Licord under drought stress. Drought stress caused a decrease in RWC at 75% FC in both genotypes. Also, the drough treatment at the level of 20% FC caused a decrease in the leaf area and the treatment of all stress levels caused a decrease in the amount of anthocyanin in both genotypes. The stress treatment at 20%FC increased the amount of chlorophyll b and total chlorophyll in SLM046 genotype. The treatment at all stress levels decreased the chlorophyll a and b, total chlorophyll and carotenoid in Licord genotype. The results showed that the expression of FNR and NTR genes increased in SLM046 genotype at higher stress levels. It seems that the SLM046 is tolerant under severe and very severe drought. The increase in FNR expression, which leads to the production of NADPH, is regulated by the NTR expression, and by regulating the expression of genes involved in oxidative stress, it can cause drought tolerance and plant survival in tolerant genotype.

Drought is a major abiotic stress that constrains the growth and yield of Canola. This study was conducted to obtain a greater insight into the drought-related hub genes, their regulatory network and relative expression pattern in tolerant and susceptible genotypes of Canola under drought stress. In present study, we sought to find some of key genes and their regulatory network involved in drought stress in Canola, and analyzed gene network, functional pathways, regulatory microRNAs (miRNAs) based on RNA-sequencing data analysis and comparing the relative expression pattern of hub genes in tolerant and susceptible genotypes by Real-time PCR technique. A total of 5275 differentially expressed genes were identified, with 3794 up-regulated and 1481 down-regulated genes under drought stress. The result showed that the most significant biological process of up-regulated and down-regulated genes enriched in response to water deprivation and light stimulus, respectively. The result demonstrated that the ACP4, RCA, FNR1, HCEF1, PRK, GDC, and MDH were some of hub genes in drought stress. The hub genes were regulated by vital drought-responsive miRNAs such as miR9558, miR854, miR172, miR834, miR390, and miR167. The relative expression pattern of investigated hub genes was different in tolerant and susceptible genotypes of Canola. The identified drought-responsive hub genes appear to play an essential role in the regulation of carbon metabolism, activation of stress signaling, and the regulation of the stromal NADP(H) redox state in response to drought stress. They are regulated by important miRNAs in a complex regulatory network that worth being considered in genetic engineering programs of Canola.

Information about the amount of genetic diversity in the germplasm and genetic relations of genotypes is essential for analyzing and designing breeding programs and could be used for assisting in genetic identification and improvement of the germplasm. In this research, the genetic diversity of 48 genotypes of the flue-cured, burley, and oriental types of tobacco was investigated by 12 ISSR, 10 SSR, and five IRAP primers. The maximum number of bands was observed in the UBC825, RTR-10, and mixed primer UBC817 + UBC826 with 17 bands, UBC817 with 16 bands, and RTR-8 with 15 bands. UBC824 with 10 and UBC823 with 11 bands showed the minimum number of bands among ISSR and IRAP primers, and PT30044 and PT30046 primers with two alleles showed the minimum number of alleles among SSR markers. In ISSR and IRAP, the observed percentage of polymorphism ranged from 76.92% for RTR-1 and RTR-7 to 94.11% for RTR-10, and in SSR markers, it was 100%. The average polymorphism percentage was 90.7%, which indicated suitable genetic diversity among the tobacco genotypes. The polymorphism information content ranged from 0.31 to 0.5 with an average of 0.42. The average diversity of Nei and Shannon indices were 0.39 and 0.58, respectively. Cluster analysis by the UPGMA method classified the 48 tobacco genotypes into five groups, containing 5, 12, 10, 6, and 15 genotypes, respectively. Principal coordinate analysis showed that the 14 first components could explain 51.49% of the total variance. The primers used in this study had high efficiency, which can be used to study the genetic diversity in tobacco.

MicroRNAs (miRNAs) are small, non-coding, and regulatory molecules that play an important role in post gene expression regulation in response to biotic and abiotic stresses. Although Canola (Brassica napus) is a globally important oilseed, little is known about its regulation mechanisms target genes of drought-responsive miRNAs. Then, in this study drought-responsive miRNAs target genes of bna-miR156b, bna-miR156c, bna-miR156g, bna-miR171a, bna-miR171d, bna-miR171e, bna-miR172d, bna-miR399a, bna-miR399b, bna-miR396a, bna-miR395d, bna-miR395e and bna-miR395f in Canola were identified by bioinformatics tools. Molecular function, biological process, cellular component, proteins interaction, and relation of their pathways were investigated. In the present study were identified 225 target genes for miRNAs. Bioinformatics study showed that ribosome, proteasome, and chaperon-related genes of RPP1C, RPL36AA, RPL9D, RPS11, RPT1A, RPT2a, RPT4A, RPN11, HSF1, HSFA1E, HSF4, and HSFB2B are targets of drought-responsive miRNAs of bna-miR172d ،bna-miR156b/c/g، bna-miR860، bna-miR396a and bna-miR395d. Ribosomes, proteasomes, and chaperons are regulated by drought-responsive miRNAs for protein regulation and stress tolerance under drought conditions. Laboratory study of identified genes in this study can be a fundamental step in the production of drought-resistant Canola cultivars in inbreeding and genetic engineering programs.

There is much information about the regulation of gene expression in response to various stresses at the transcriptional level. Nevertheless, there is limited information about this process at the post-transcriptional level. The diversity and complexity of miRNA regulation indicates their importance in biological processes. Many miRNA regulatory modules can form a complex miRNA-mRNA regulatory network. Therefore, research on miRNA-mRNA regulatory networks can provide valuable information for understanding complex biological processes. These data are very important to further study the stress tolerance mechanisms in plants, especially in rapeseed. In this research, the selection of miRNAs related to drought and salinity stress was made by reviewing the articles on abiotic stresses. Then the target genes were identified using the sequences of mature miRNAs and psRNATarget online software. A gene list of 225 identified target genes was prepared using the UniProt database. Their functional pathway was identified utilizing the DAVID bioinformatics database and KEGG database according to default parameters. Investigations showed that these target genes were involved in several biological pathways including ribosome, spliceosome, proteasome, purine metabolism, selenocompound metabolism, and sulfur metabolism. In addition, the STRING database was used to check co-expression genes. Our result indicated the existence of 37 co-expression genes among the identified target genes.

Abiotic stresses such as drought and salinity significantly affect plant growth and performance. Plants use strategies to adapt and tolerate drought and salt stress that may threaten their survival during their life cycle, one of which is miRNA-mediated post-transcriptional regulation.

In the current research, miRNAs that showed significant expression during salt and drought stress were selected by checking the references to investigate this phenomenon in rapeseed plants. The phylogenetic tree was constructed to analyze and compare the evolutionary relationships and conservation of MicroRNA effective in drought and salinity stress in Brassica napus, Brassica rapa, and Brassica oleracea species. Target genes for selected miRNAs were identified using psRNATarget online software. Categorization and gene ontology of target genes and identification of biological pathways were accomplished; also, proteins were classified based on molecular function and biological processes. The Protein-protein interaction was analyzed to comprehensively interpret the relationships between the target genes. In the present study, 225 target genes for miRNAs were identified.

After examining the protein interaction network, it was found that there were the most interactions between ribosomal, proteasome subunits and the ubiquitin-proteasome system. This result determined that drought and salinity stress leads to the activation of various biological systems and pathways and changes in gene expression along with the activation of the protein synthesis machine and alterations in protein content. By activating post-transcriptional gene regulation (PTGR) and post-translational modifications (PTMs), the plant regulates the abundance, activities, intracellular distribution, and transport of regulatory proteins involved in various growth processes as well as stress response. 

The results of this study will lead to a broader perspective regarding stress and its effect on the pathways involved in cellular processes and will reveal the wide dimensions of the stress response.

In this study, geneti diversity of 28 genotyped of rapeseed using 7 markers ISSR, 3 indicates Retrotransposons and 22 combined markers were evaluated. The results of cluster analysis and molecular evaluation UPGMA with method by criteria simple matching coefficient using data from primer ISSR, Retrotransposons and hybrid primer ISSR and Retrotransposons 28 genotypes studied in 3 groups, the groups were: 14, 9 and 5 genotypes are among the groups, the first group is the largest group, but the morphological traits of 28 genotypes by UPGMA and Euclidean distance criteria were divided into 4 groups. Grouping results of cluster analysis by linear discriminant analysis using Fisher's 100 percent for molecular.

Determining the classification, phylogenetic relationships, and genetic diversity in citrus is critical to determining genetic relationships, identifying germplasm, controlling genetic erosion, establishing breeding programs, and registering new cultivars. Researchers believe that genetic diversity is very important and is an essential part of any breeding program. The use of molecular techniques to assess DNA level, genetic diversity, and genetic distance is widely used in germplasm samples. Therefore, the aim of this study was to investigate the genetic diversity of orange genotypes using molecular markers.

In order to investigate the genetic diversity, 40 orange genotypes of Rudsar city in Guilan province were evaluated. DNA extraction from young leaf samples was performed using the Edward method with slight modifications. After DNA extraction of genotypes, polymerase chain reaction (PCR) was performed with 15 primers. Amplified genomic DNA images were analyzed and the data were entered into Excel software as a matrix. Polymorphic information content, marker index, effective multiple ratio, number of effective alleles, Shannon index and straw gene diversity were also examined.

The 15 primers used in this study were able to create a total of 140 bands, of which 101 were polymorphic bands, including TOS-1 and TOS-2 primers with 9 bands, UBC811 primer and UBC8821 + UBC826 hybrid primer with 4 Tape created the least number of polymorphic strips. Primers TOS-1, UBC813, UBC823 and TOS-2 and UBC811 with the highest PIC value, best markers and high values of effective allele, Shannon index, straw gene diversity as the top primers to study genetic diversity in this study, respectively were. Based on the results, the markers used were able to evaluate the genetic diversity of genotypes. The content of polymorphic information in this study ranged from 0.22 to 0.45. Principal coordinate analysis showed that the first three components were able to explain a total of 29.08% of the total variance. Cluster analysis by the farthest neighbor method divided 40 orange genotypes into five distinct groups based on similarities and differences. The grouping accuracy obtained from the cluster analysis was confirmed by the Fisher linear focal detection function 100%. The markers used in this study showed acceptable polymorphism. Also, the study of morphological traits and molecular markers used in this study showed the degree of similarity and differences of genotypes, although there were differences in the results of morphological and molecular studies that can be observed. Due to the high accuracy of molecular markers. However, using appearance and morphology, it was possible to distinguish orange genotypes from each other.

The results of this study showed that there is a high genetic diversity among orange genotypes. Due to the fact that the markers used in this study showed acceptable polymorphism, they can be used in future research on this plant and other citrus plants. In general, according to the results of this study, that ISSR and retrotransposon primers can be used as a simple molecular method based on PCR and relatively safe and reliable in determining the level of genetic diversity and phylogenetic relationships in citrus.

In the present study, 11 ISSR, 2 Retrotransposon and 15 Retrotransposon + ISSR composed markers (REMAP) were evaluated among 27 genotypes of Soybean. 130 polymorphic bands were produced from 28 primers. The maximum percentage of polymorphism were 77% for UBC808, 54% for TOS-2 and 70% in UBC808+TOS-1 marker. The mount of Nei′s, Shanon and PIC index for UBC808, UBC811, UBC825, HB-12, TOS-2, UBC807+TOS1 and UBC834+TOS-1 indicated that theses markers could be used to assessment of genetic variation. The result of cluster analysis using complete linkage algorithms clustered 27 studied genotype in 4 distinct groups with 4, 9, 9 and 5 genotype in respected group. Discriminant function analysis using the Fisher′s linear method showed that the complete linkage method separated the genotypes with 96/3 percent accuracy. Morphological characteristics of genotype were evaluated in a completely randomized design with factorial arrangements whit two factors, The first factor were salt stress treatments at 0 (check), 30, 60 and 90 mM NaCl and the second factors was genotypes. ANOVA showed significant differences among varieties and level of Treatment for all measured morphological traits, and in interaction of cultivar×stress for all traits except Shoot fresh weight, shoot dry weight, root dry weight and shoot's weight difference between wet and dry. The cluster analysis based on within group′s method clustered genotype at different salt stress treatment in 4 clusters, and the accuracy of cluster analysis revealed by discriminant analysis was 92/6%. The correlation between the two similarity matrices was not significant by Mantel test. Analysis using marker-assisted selection of bands that enhance salt tolerance traits mean they can be used to identify resistant soybean genotypes..

Plants are often exposed to a variety of environmental stresses such as drought and salinity, which leads to osmotic stress in the plant and ultimately reduces crop growth and productivity. Identification of effective genes at different treatments of osmotic stress can be very helpful in finding genes that are effective in tolerating plant stresses. Therefore, the aim of this study was to identify the hub genes of Arabidopsis model plant in osmotic stress and to introduce them for crop breeding under environmental stresses .

In this study, Arabidopsis microarray data that were exposed to mannitol-induced osmotic stress for 1.5, 3, 12 and 24 hours were analyzed separately by GEO2R online tool. Genes with significant expression were identified and the most important genes at each stress level were identified using bioinformatics tools. Then, the hub genes in osmotic stress were identified and their protein interactions and biological processes were studied and discussed .

The result showed that 26, 79, 138 and 184 genes had significant expression at 1.5, 3, 12 and 24 hours after stress, respectively. Based on protein network analysis and biological processes, SDA1, CRK11, CYP81F2, EDA39, PLA2A, T1K7_24, F6N7_24, AT2G25735 and MRH10_18 genes were reported as hub genes at different levels of osmotic stress. The results of molecular function analysis of hub genes showed that these genes involved in oxidative stress, response to hypoxia, regulation stomata movement, hypersensitive response, response to chitin, induced systemic resistance, indole glucosinolate biosynthetic process, defense response by callose deposition in cell wall, response to cadmium ion, phytochelatin biosynthetic process, arsenite transport, defense response to bacteria, insects, fungi, viruses and other environmental stress responsive biological process. 

It seems that the key genes introduced in this study can be used to breed crops under environmental stresses that cause osmotic stress in plants.

In order to study the effects of drought stress induced by polyethylene glycol 6000 on germination components of 21 bean genotypes, a randomized complete design with factorial arrangement of one drought level (-0.148 MPa) and control level (0), in 3 replication and with the purpose of determining the resistance and susceptible genotype, was conducted. Results of anova indicate that all genotypes in all studied components (root, shoot, fresh weight of root and shoot, dry weight of root and shoot, growth rate root and shoot, root to shoot length ratio, difference of fresh and dry weight root, difference of fresh and dry weight shoot)were affected significantly by drought stress. Genotype effect and also the interaction between genotype and drought, was significant for all studied components. According to results of cluster analysis with the ward method, all genotypes in normal and drought conditions, were placed into four different groups, the Ghalaf Siyah and Pak genotypes were chosen as resistance and susceptible genotypes in drought stress conditions.In this study the expression patterns of three drought induced-genes was investigated in two Ghalaf Siyah (resistant genotype) and Pak (sensitive genotype) using Real time PCR technique. After RNA extraction and cDNA synthesis, expression of three genes, including,GR, PRX and APX were studied in the seedling stage of Ghalaf Siyah and Pak genotype under drought stress for control, 72, 144, 192 and 240 hours of the treatments.The results indicated that in Ghalaf Siyah genotype the drought  induced-genes generally had higher expression than Pak cultivar.Expression of three genes PRX, GR and APX at the 240 h in the tolerant genotype, it was two, four and six more than the sensitive genotype.

To investigate the effect of osmotic stress induced by polyethylene glycol 6000 on seed germination components and identifying drought tolerant and susceptible genotypes, 21 rice genotypes were studied at three levels of osmotic stress (0, -7.5 and -15 MPa) with factorial arrangement in a completely randomized design with three replications. The results indicate that there were significant differences among genotypes in different levels of osmotic stress for all studied traits including radicle length, shoot length, radicle to shoot length ratio, radicle fresh weight, radicle dry weight, shoot fresh weight and shoot dry weight. The effect of genotype and genotype osmotic stress interaction were significant in all studied components. Based on measured traits, the genotypes IR28 and Line 416 were selected as susceptible and tolerant genotypes to osmotic stress, respectively. After RNA extraction and cDNA synthesis, the expression pattern of four drought responsive genes (SOD, FNR, APX and NDH) in two genotypes, IR28 and 416, at seedling stage under treatments of 0, 4, 8, 10 and 24 hours of the dehydration stress were studied using real time PCR technique. The results of this study showed that drought responsive genes had higher expression in the tolerant Line 416 than the sensitive genotype IR28 and the expression of all genes except FNR increased with increasing osmotic stress. Also, APX gene didn’t show the significant expression in either genotype, but showed the highest expression at 24 hours after stress in the sensitive genotype IR28.

Under the iron toxicity conditions, one of the most important limiting factors of rice production in agricultural lands is the increase of active oxygen radicals and thus decrease of plant growth and development. In this study, the effect of iron induced toxicity at 0 (control), 100, 250, 400 and 500 mg/l (Fe-EDTA) levels were investigated on some morphological traits, relative expression of G6PDH photosynthetic gene and activity of peroxidase enzyme in two rice genotypes, Pokkali (tolerant) and IR64 (susceptible), at four-leaf growth stage under hydroponic conditions with Yoshida nutrient solution. The experiment was carried out as factorial with two factors, genotype and iron concentration (two and five levels, respectively), in a completely randomized deshgn with three replications. The results showed that the interaction of iron toxicity and genotype had significant effect on all studied traits except root dry weight. Cluster analysis using farthest neighbor divided the ten studied treatments into two separate groups. Principal component analysis showed also that 66% of the total variation was explained by two principal components. Applying iron toxicity stress reduced the relative expression of G6PDH gene in both genotypes, exept that the relative expression of this gene in the Pokkali genotype decreased with the application of low stress levels, but in the IR64 genotype, the decrease in expression of this gene observed only at high stress levels. The lowest activity of peroxidase enzyme was observed in both Pokkali and IR64 genotypes at 100 mg/l iron and the highest activity were observed at 400 and 250 mg/l, respectively. It seems that decreasing the expression of G6PDH gene at low stress levels and increasing the activity of peroxidase enzyme in the tolerant genotype can reduce the amount of hydrogen peroxide induced by iron toxicity.

Iron toxicity lead to increasing of free oxygen radicals, oxidative stresses and sever yield reduction of Rice. One of the plant responses for physiochemical and biochemical regulation to stresses is change of antioxidant enzyme contents. In this study the effect of five treatments of iron (Fe-EDTA) (0, 100, 250, 400 and 500 mg/li-1) on relative expression of glutaredoxin (GRX), thioredoxin (TRX), peroxiredoxin (PRX) and catalase (CAT) genes of IR64 (susceptible) and Pokkali (tolerant) genotypes of Rice in Yoshida hydroponic media by Real time-PCR technique investigated. The results showed that the relative expression level of CAT gene in different levels of iron in Pokkali genotype was higher than IR64 genotype. The relative expression level of PRX in IR64 genotype in all of the levels was similar. The relative expression level of TRX in Pokkali genotype was not significant. The relative expression level of GRX in the most of stress levels in Pokkali genotype was higher than IR64 genotype. Low level iron result in increasing of relative expression level of CAT, GRX and TRX in IR64 genotype. But with increasing level of iron was not significant change in expression of genes. Also in the most of the iron level relative expression of genes in Pokkali was higher than IR64. Probably lose of change in gene expression levels in high level iron and low gene expression in IR64 is one of the reasons of its susceptibility to iron stress.

Increasing of reactive oxygen species (ROS) under iron toxicity is considered as one of the major constraints to rice production. In this study the alterations of SOD, GPX1 and MDHR expression level in two genotypes of rice, Pokkali (as tolerant) and IR64 (as sensitive) were monitored under different concentrations of iron levels [(0) (nonstress)], 100, 250, 400 and 500 mg/lit-1Fe-EDTA). The treatments were done when the plants were at 4-leaf stage and lasted for two weeks. Results showed that the expression levels of genes in Pokkali were higher than IR64. The expression level of SOD in IR64, increased at iron concentration increased, while it decreased at higher Fe-level. The expression level of GPX1 was increased in IR64, but decreased in Pokkali. The expression level of MDHR in IR64 was decreased at early stage of Fe-treatment, but then increased. Inversely, in Pokkali MDHR expression reduced constantly under Fe stress. Overall, the relative over expression of genes in Pokkali and presence of different expression levels of them between different concentrations of Fe in tolerant and sensitive genotypes indicate that the gene could remarkably effect on the tolerant level of pokkali by reducing ROS production under Fe-toxicity.

Drought is one of the most devastating environmental stresses that adversely affect plant metabolic processes. Many plant genes such as photorespiration ones are involve in response to drought stress. In the present study, the effects of drought stress on the expression level of two peroxisomal (Hydroxy pyruvate reductase (HPR1) and Glycolate oxidase (GO)) and two mitochondrial (Serine hydroxy methyl transferase (SHMT) and Glycine decarboxylase (GDC)) genes were studied in susceptible (Hayola308) and tolerant (SLM046) genotypes of canola (Brassica napus) under stress (irrigation cut at flowering stage) and non-stress conditions. The result of real time-PCR showed that in Hyola308 genotype the expression level of GO gene at 48, 72 and 96 hours after stress was higher than SLM046 genotype. In Hyola308 genotype, the highest expression level of GDC gene observed at 48 hours of stress and then decreased. The highest relative expression level of SHMT gene in both Hyola308 and SLM046 genotypes detected at 24 hours after stress and then in SLM046 genotype, its level decreased at 48 hours after stress, while in Hyola308 genotype, its expression declined over the time of exposure to stress. SLM046 genotype showed highest amount of HPR1 expression level at 48 hours after stress. It seems that the expression of photorespiration genes in SLM046 genotype increased at the initial times of exposure to stress and with continue the stress, it showed more adaptation to stress and control the photorespiration unlike Hyola308.

This study was conducted to grouping of 10 genotypes of canola via ISSR and IRAP markers and genotype resistance to drought. Eighty five polymorphic bands were produced using 19 individuals and combinations of ISSR and IRAP, and polymorphism varied between 50 to 100. Cluster analysis with UPGMA method placed the 10 genotypes in tree cluster, which includes 5, 3 and 2 respectively. Cluster analysis of germination results based on Euclidean distance with UPGMA method assigned treatment in four different groups consists of 11, 5, 9, and 15 genotypes respectively. Fisher’s linear Discriminant Function Analysis confirmed validity clustering analysis with 95%. The second group had the highest value, for most economical traits. SLM046 genotype could be introduced as resistant genotype by placing different treatments of its in one group. The fourth group included genotypes that had low value for most characteristics. Factor analysis results based on principal components showed that three factors named plumule, radicle and germination percentage, which determined 88.31 percent of total variation. First region was detected as good region on the base first and second factor evaluation. Genotypes in this area were favorable response to drought stress and could be introduced as resistant genotype at germination stage.

In order to study of genetic diversity and similarity among four native olive cultivars including ‘Mari’, ‘Zard’, ‘Shengeh’ and ‘Rowghani’, these cultivars were evaluated in five regions including Ali abad, Gilvan, Tarom, Manjil and Jamal abad at 2012-2013. There was a significant difference among studied individuals. The correlation coefficient analysis among studied traits showed that there was a good correlation among quantitative traits such as flesh, fruit weight, fruit shape and stone shape, while the correlation among qualitative traits was low. The results of PCA earned three components which accounted 91.93 percent. The scatter diagram of individuals based on two first components showed a good distinction for individuals. The cluster analysis separated six distinct groups in which Mari population formed three neighbour groups. ‘Zard’ population also showed high homogeneity, while ‘Shengeh’ showed the most dispersion however it was closely similarity to ‘Rowghani’ population.