MicroRNAs are endogenous noncoding RNA that play vital roles in all plant cellular metabolic processes by mediating target gene expression.To date, miRNAs in Taraxacum spp., which is an important industrial plant, have remained largely unknown.In the present study, 970 miRNAs from 399 families were identified in Taraxacum spp by conducting computational approaches.The most frequent miRNAs in Taraxacum spp was miR5021.According to the KEGG results, miR5021, miR838, and miR1533 are related to the terpene biosynthesis pathway, while miR5015b, and miR1436 are involved in the starch and sucrose biosynthesis pathways.Quantitative real-time PCR assay was performed to validate the expression levels of five predicted miRNAs and 3-Hydroxy-3-Methylglutaryl Coenzyme A Reductase (HMGCR) and invertase as the target genes.Results indicated that the highest relative expression of miR1533 and miR1436 occurred in the flower, while the highest transcripts levels of miR5015b were observed in the stem.In addition, the higher relative expression level of the miR5021 and miR838 was consistent with the lower expression level of the HMGCR gene in all tissue, suggesting that miR5021 and miR838 are involved in regulating HMGCR gene expression.Since mevalonate pathway is the main source of isopentenyl pyrophosphate, which is used in the synthesis of rubber, miR5021 and miR838 play an important role in the production of rubber by regulating the expression of HMGCR enzyme.These findings will accelerate future perspective studies on the regulatory mechanisms of miRNAs in Taraxacum koksaghyz.
Variation in metabolism and partitioning of carbohydrates, particularly fructans, between annual and perennial Cichorium species remains a challenging topic. To address this problem, an annual (endive, Cichorium endive L. var. Crispum; Asteraceae) and a biennial species (chicory, Cichorium intybus L. var. Witloof; Asteraceae) were compared with in terms of variability in carbohydrate accumulation and expression patterns of fructan-active enzyme genes, as well as sucrose metabolism at various growth and developmental stages. In general, constituents such as 1-kestose, nystose, and inulin were detected only in the root of chicory and were not present in any of the endive tissues. For both species, flower tissue contained maximum levels of both fructose and glucose, while for sucrose, more fluctuations were observed. On the other hand, all the genes under study exhibited variation, not only between the two species but also among different tissues at different sampling times. In endive root compared to endive leaf, the expression of cell wall invertase genes and sucrose accumulation decreased simultaneously, indicating the limited capacity of its roots to absorb sucrose, a precursor to inulin production. In addition, low expression of fructan: fructan fructosyltransferase in endive root compared to chicory root confirmed the inability of endive to inulin synthesis. Overall, annual and biennial species were different in the production of inulin, transport, remobilization, and unloading of sucrose.
The effect of different hormones on fructan accumulation and the genes regulating biosynthesis and degradation is known; however, information on hormonal interaction mechanisms for fructan content and mean degree of polymerization (mDP) is limited. Cell suspension cultures of chicory were prepared and treated with abscisic acid (ABA), auxin (AUX), ethylene (ETH), ABA + AUX or ABA + ETH, then inulin concentration, mDP of inulin and expression of FAZY genes was determined. A low concentration of AUX and ETH increased fructan content, while a high concentration of AUX and ETH decreased it. Exogenous ABA increased mDP of inulin and this coincided with the low expression of 1-FEHII. In hormone interactions, ABA changed and adjusted the effect of both AUX and ETH. ABA, together with a low level of AUX and ETH, resulted in a decrease in inulin content and increase in mDP, which coincided with low expression of FEHII. ABA together with a high level of AUX and ETH caused an increase in inulin content with a lower mDP, which coincided with high expression of biosynthesis (1-FFT) and degradation (1-FEHII) genes. The effect of both AUX and ETH was almost the same, although the effect of ETH was more severe. ABA had a modulating role in combinations with AUX and ETH. Among biosynthesis and degradation genes, the expression of 1-FEHII was more affected by these hormones.
The effect of different hormones on fructan accumulation and the regulation of biosynthesis and degradation genes has been confirmed; however, information of hormonal interaction mechanisms on fructan content and mean degree of polymerization (mDP) is limited. Cell suspension cultures of chicory were prepared and treated using abscisic acid (ABA), auxin (AUX), Ethylene (ETH), ABA+AUX, and ABA+ETH, then inulin concentration, mDP of inulin and expression of FAZY genes were determined. Low concentration of AUX and ETH increased fructan content and high concentration of AUX and ETH decreased it. Exogenous ABA increased mDP of inulin and it coincided with the low expression of 1-FEHII. In hormonal interaction, ABA changed and adjusted the effect of both AUX and ETH. ABA with a low level of both hormones resulted in a decrease in inulin content and increasing mDP and it coincided with low expression of FEHII. ABA with a high level of both hormones caused increasing in inulin content with lower mDP and it coincided with high expression of biosynthesis (1-FFT) and degradation (1-FEHII) genes. The effect of both AUX and ETH was almost the same although the effect of ETH was more severe. ABA had a modular role in both combinations with AUX and ETH. Among biosynthesis and degradation genes, the expression of 1-FEHII was more affected by hormones.
Effect of Drought Stress on Antioxidant Enzymes Activities and Some Physiological Traits in Chickpea (Cicer Arietinum L.)
Chicory (Cichorium intybus L.) is a typical Mediterranean plant distributed throughout the world and has different commercial uses such as salad, forage, inulin production, and coffee substitute. Health promoting characteristics of inulin as a prebiotic compound led to its biosynthesis pathway discovery. Two enzymes, namely, 1-SST and 1-FFT, are involved in inulin biosynthesis during normal phase. By cold nights or other factors, 1-FEHs enzymes degrade inulin to fructosyl units. To compare the strength of function of these genes in a wild type genotype with root type cultivar (Orchies) of chicory at three stages, i.e. 60, 90, and 120 days after seed planting, relative expression of those genes along with their corresponding metabolites were assessed using RT-qPCR and HPLC. Expression results showed that, unlike Orchies cultivar, relative expression of 1-SST in wild type genotype was ascending, relative expression of 1-FFT was very low and constant and there were high levels of relative expression of 1-FEH I gene during growing season due to flowering initiation. Also, glucose and fructose concentrations were upward, as result of 1-SST and 1-FEH I enzymes activity in wild type genotype, respectively. Degree of Polymerization (DP) of produced inulin had almost no increase due to low function of 1-FFT enzyme in the wild type genotype (DP< 5), but Orchies cultivar produced inulin with DP> 10 as expression of 1-SST decreased during growing season. So, it is possible to make inulin pathway in root type chicory cultivars more efficient by expanding and overexpressing 1-SST function using such wild resources through backcross breeding or biotechnology methods.
Dynamic transcriptional variations of genes encoding fructan active enzymes (FAZYs; 1-SST, 1-FFT, 1-FEHI, 1-FEHII) alongside their potential contributions regarding production/degradation of various carbohydrates (i.e., fructose, glucose, sucrose, 1-kestose, and inulin) were scrutinized in the two distinct genotypes of chicory (Cichorium intybus L.) namely “Germany variety” and “Iranian landrace”, at flowering stage. Germany variety accumulated overall more amounts of fructose, sucrose, and inulin, while Iranian landrace contained the highest proportion of 1-kestose, and glucose. Furthermore, both 1-SST and 1-FFT genes were dramatically up-regulated in the root-harvested samples of both genotypes, though maximum transcripts of 1-SST and 1-FFT were respectively detected in landrace and Germany variety, suggesting a cultivar- and tissue-dependent phenomenon. Instead, in both genotypes, maximum transcript levels of 1-FEHI were detected in stem, while root, flower and leaf tissues possessed inferior magnitudes. Considering 1-FEHII, both genotypes exhibited a down-regulated behavior in four tissues (excluding landrace stem). Meanwhile, the chicory MYB transcription factor (CiMYB17) transcriptionally fluctuated among four tissues of both chicory genotypes, and exhibited significant correlation only with 1-FEHI in Germany, a moderate correlation with 1-FEHI in landrace, and lower associations with 1-SST, 1-FFT, and 1-FEHII, indicating its trivial regulatory roles in the complex regulation of FAZY gene expression, and subsequently biosynthesis/degradation of fructans under normal circumstances. Regarding landrace, both 1-SST and 1-FFT correlated only with glucose, while for Germany variety, 1-SST had a strong association with inulin, 1-ketose, alongside glucose, and 1-FFT had a strong correlation only with glucose. However, both 1-FEHI and 1-FEHII exhibited no considerable associations with all the carbohydrates studied. Notably, 1-FEHII negatively correlated with inulin content, indicating an “antagonistic” effect between inulin accumulation/production and 1-FEHII activity. The results, overall, demonstrated that variations in genotypes and/or tissues under study can synergistically/antagonistically influence expression patterns of FAZY genes alongside production/degradation of the corresponding fructans.
The roots of Rubia tinctorum L., the common madder contain natural red dye known as alizarin. In the current study, central composite design of response surface methodology was employed for modeling of fungal elicitor treatment on natural alizarin production in uniform hairy root cultures of common madder in liquid 1/2 B5 medium. Upon fungal elicitation assay, using two fungal mycelia elicitors ( Aspergillus niger and Bipolaris maydis ) at three different times (0, 12 and 24h), the production of alizarin was determined. According to the results, after 24h; modeling and optimization conditions, including combination of 2 % of both elicitors for alizarin production equal to 10.0 mg.g -1 DW was evaluated. Optimal process parameters have been determined by using a high desirability value of 1.00 in Design-Expert ® software. Our results, altogether, offer a promising method regarding to the improvement of the alizarin production, as a pivotal natural dye in industrial applications.
Chicory (Cichoriumintybus L.) is an important industrial crop which is used for inulin production. Inulin is widely applied as food ingredient due to its health promoting properties. For the first time, attempts were made to investigate thirteen endemic chicory genotypes including three pumilum populations, along with five root chicory cultivars, four witloof chicory varieties and a crispum endive to find their phylogenic relationships based on some diagnostic morphological traits as well as comparing their fresh root yield, total carbohydrate content as indicator of inulin percentage, and inulin yield in RCBD with three replications, 2013-14. In general, with the exception of Firizi landrace which was classified in C. intybus class, the other endemic genotypes exhibited the maximum similarity with C. endivia, as all formed a monophyletic clade. The highest inulin yield was obtained for ‘Orchies’, after that for ‘Schepens’, ‘Tilda’ and ‘Hera’, respectively, due to firstly their higher root yield and secondly their high inulin percentage. On the whole, fault of flowering at the first year of life cycle of endemic genotypes made intensive selection and breeding of Iranian genotypes for bolting resistance priority work before applying them to build root chicory varieties
In this study, the Rysto gene, originaly found in wild potato (Solanum stoloniferum), confers extreme resistance against PVY. It was identified in 21 potato clones and varieties and they were evaluated for some agronomic traits. For this purpose five trials were conducted. In first trial 320 potato genotypes were planted on the farm and 55 symptomless clone and cultivars were selected. In second trial, 55 genotypes along with sensitive control genotype (Desireh) were planted in 20 cm pots in the greenhouse at 15-20 °C with three replications. After five weeks, upper leaves were infected artificially with sap from tobacco fresh leaves checked for infection with PVYNTN and additional infections were repeated after 48 hours. Symptoms were recorded and all plants were tested by enzyme-linked immunosorbent assay (ELISA) about 4 weeks after inoculation. Plants that showed visual symptoms or/and gave at least a positive ELISA result were considered as susceptible and symptomless response with negative ELISA results were considered as resistant. In third trial, 23 genotypes were planted in the greenhouse and the PVY infected young tobacco shoots were grafted to symptomless genotypes with negative ELISA results with three replications and were selected as resistance genotypes. In fourth trial, all the PVY resistant genotypes were checked by molecular marker (STM0003) for detection of Rysto gene. Finally four potato varieties (Jelly, Sante, White Lady and Savalan cultivars) and 19 advanced clones were regarded as carriers of Rysto gene. In the fifth experiment genotypes were evaluated for marketable tuber yield of varieties and clones resistant to virus PVY in field conditions and 397009-8 clone was selected as high-yielding and tolerant genotype to PVY virus. Also, This clone did also have appropriate quality traits like oval-round tuber shape, uniform tubers, short stolon length, light yellow flesh color, yellow skin color, good tuber dry matter percent, tuber flesh texture of relatively soft (multipurpose) and shallow depth tuber eye.
Salinity is one of the major stresses that limits crop production worldwide and affects most physiological activities in plants. In order to study the genetic control of salt stress in the model legume Medicago truncatula Gaertn., an experiment was undertaken to determine the genetic variability and to identify quantitative trait loci (QTLs) controlling several traits related to plant growth and physiology in a population of recombinant inbred lines. Shoot and root DW, relative water content, leaf area, chlorophyll content, chlorophyll fluorescence parameters, and Na+ and K+ in shoots and roots were measured. The experiment was carried out with three replications. ANOVA showed a large genetic variation and transgressive segregation for the traits studied, suggesting putative complex tolerance mechanisms. A total of 21 QTLs were detected under control conditions and 19 QTLs were identified under 100mm salt stress conditions, with three QTLs being common to both situations. The percentage of total phenotypic variance explained by the QTLs ranged from 4.6% to 23.01%. Overlapping QTLs for different traits were also observed, which enables us to discriminate independent traits from linked ones. The results should be helpful information for further functional analysis of salt tolerance in M. truncatula.
Medium optimization for hairy root cultures producing secondary metabolites was studied through statistical experimental design. In the following, one factor model of response surface methodology (RSM) was employed to formulate the L-Arginine amino acid levels alongside three categorical factors including bacterial strains (ATCC 15834, C58C1 and R1000), type of explant (Leaf and Stem) in co-cultivation media (B5 and MS) for hairy root induction of Madder ( Rubia tinctorum L.). Design of experiment and data analysis was carried out by using Expert-Design ® 7.1 software. According to the results, modeling and optimization conditions, including L-Arginine concentration 1.00 mM; bacterial strain; C58C1, leaf explant and B5 medium for HR induction frequency equal to 58% was evaluated (Desirability point=0.986). These optimal conditions predicted by RSM were confirmed to enhance hairy root induction as an application potential for biotechnological implementation to produce the anticipated compounds.
In order to study the quantitative variability of malting quality-related traits and to determine the genomic locations which control these traits, an experiment was conducted using one hundred fifty double haploid (DH) lines of barley and their two parents ‛Steptoe’ & ‛Morex’. Protein content (%) was measured using Kjeldahl method, diastatic power calculated with Lintner formula, Malt extract was measured for each by special weight achieved and based on Malt Berix Charts. Transgressive segregation in both directions was observed for all traits. Genetic map is fairly saturated and comprising 327 RFLP markers with a total length of 1226.3cM with an average marker spacing of 3.75cM. Seventeen QTLs by LOD≤2(LRS≤9.21) controlling different studied traits were identified for all studied traits. Total phenotypic variance explained by these QTLs varies from 23.2 to 45.05%. Highest LOD scores were obtained for QTL’s controlling diastatic power (Qdip3Ha) on chromosome 3H, and lowest LOD scores were obtained for QTL’s controlling seed yield per plant (Qsyp1Hb) on chromosome 1H. Therefore gain through marker-assisted selection (MAS) in this population would be limited and some of the “Steptoe× Morex” population was developed with the intention of isolating and advancing barley lines for release to the malting quality.
Despite the importance of barley as an animal feed, its forage quality has usually been neglected in breeding programs. In order to map the genomic regions, which modify barley forage quality, a population of 72 F 1 -derived doubled haploid lines (DH) from the cross “Steptoe/Morex” and their two parents were sown in Karaj and Zabol provinces of Iran, in each under a randomized complete block arrangement with two replications. Forage samples were oven-dried and ground and dry matter digestibility (DMD), acid detergent fiber (ADF), neutral detergent fiber (NDF), acid detergent lignin (ADL), crude fiber (CF), crude protein (CP), water-soluble carbohydrates and ash content were measured by NIRS. Analysis of variance showed that genotype, environment and genotype-environment interaction have significant effects on almost all studied traits. Several QTLs were resolved for each studied trait in both environments. Highest LOD scores were obtained for CF, ADF and DMD on chromosome 2H and for ash and CP on chromosomes 3H and 5H, respectively. QTLs for NDF were present on all chromosomes except 4H and 7H. QTL × environment interaction and the specificity of the QTLs are discussed.